12-14 November, 2014 How the Australian table grape industry looks to the rest of the world Australia’s major export varieties Australian Grape Growing Areas Thompson Seedless Emerald Ti Tree Alice Springs Mundubbera Carnarvon Crimson Seedless St. George Cunnamulla Swan Valley Stanthorpe Red Globe Flame Seedless Grape exports by Australian States Menindee Riverland Bunbury Menindee Seedless Sunraysia Region Mildura Robinvale % VIC 93.85 5% NSW 4.6 8,000 120,000 of grapes produced hectares tonnes 330 6% QLD .8 million SA farm gate value .41% WA .23% Aussie grape export varieties and seasonality Major M Maj Ma ajo jor Export Expo Expo Ex p rtt V Varieties ariie ar ietities ies Dawn Daw a n Seedless (WA W only) y Menindee Seedless Thompson Seedless Crimson Seedless Flame Seedless Ralli Seedless Red Globe Autumn Royal Midnight Beauty Seeds Seed Se eds ds Nov Nov No Dec Dec De Jan Jan Ja Feb Feb Fe Mar Mar Ma A Ap Apr pr May May Ma Welcome to Mildura Organising Committee’s foreward Dear 7th International Table Grape Symposium Participants, On behalf of the 7th International Table Grape Symposium (7ITGS) Organising Committee and the Australian Table Grape Association (ATGA), we formally welcome you to Mildura, Australia for the 7ITGS. Held every three to four years, the symposium is the premier international event for the table grape industry, presenting the latest scientific research into table grape production to an audience of more than 250 delegates from around the world. This year is especially significant in that it marks the event’s 20th anniversary. The symposium’s history can be traced back to 1994 in Anaheim, California, almost 20 years ago. Since then it has been held in South Africa, Chile, California and now Australia. The Organising Committee is confident that your journey to Australia will be worthwhile both professionally and personally. We hope you value this 7ITGS event and we look forward to showcasing the very best of what Australia has to offer. Yours sincerely, Planning and Scientific Committee Mark Krstic AWRI Jeff Scott CEO ATGA Rowena Norris ATGA Allison McTaggart ATGA Paula Smith ATGA Peter Clingeleffer CSIRO Jennifer Hashim-Maguire AUSCAL Viticulture Colin Gordon WA DAF Rachael McClintock R&D Viticultural Service The 7ITGS will be held at the recently renovated Mildura Arts Centre (MAC), in the heart of the Australia’s Sunraysia table grape production region and will showcase the very best of what regional Australia has to offer. Irrigation in the Sunraysia region was established 1886 by George and William Chaffey, Australia’s first irrigation scheme. The Chaffey brothers were approached by the then Victorian Premier Alfred Deakin who was under pressure to open up more land for farming and settlement. Now Mildura is the heart of Australia’s largest table grape producing region and gateway to the iconic junction of the Murray and Darling Rivers. The 7ITGS has attracted much international interest. The oral program is packed with presentations from over 40 presenters from a range of countries including Australia, the United States, Israel, Italy, Portugal, South Africa, Chile, Brazil, Spain and Argentina. The poster session also contains an impressive array of presentations from over 30 different authors. In addition delegates are treated to a great social program with plenty of networking opportunities. This includes an impressive indigenous cultural experience during the Welcome ceremony, grand Symposium Gala Dinner, Murray River Paddleboat cruise and post-symposium tour of the Sunraysia table grape production region. We thank all those who have assisted during the organisation of the symposium and its proceedings, especially the speakers and the generosity of our valued sponsors for without their support this event would not be possible. 7th International Table Grape Symposium 1 2 7th International Table Grape Symposium PROGRAM Symposium Program Mildura Arts Centre, 11 – 14 November TUESDAY, 11 NOVEMBER 1730-1930 Pre-Symposium Registration and Welcome Function, Mildura Arts Centre Sponsored by Sun World International WEDNESDAY, 12 NOVEMBER 0730-1800 Registration desk open (tea and coffee on arrival) 0830-0840 Welcome and Official Opening 0830 Welcome to the 7th International Table Grape Symposium Mark Krstic, Chairman 7th International Table Grape Symposium Organising Committee 0840-1020 Session 1 Table Grape Production and Marketing: Future Challenges and Opportunities Moderator: Richard Lomman Chair ATGA 0840 Overview of table grape production in Australia Jeff Scott, CEO ATGA 0900 Keynote Address Impact of projected climate change on key table grape growing regions around the world Gregory Jones, Department of Environmental Studies at Southern Oregon University 0930 Keynote Address Management of food safety issues in fresh fruit production Richard Bennett, Technology Manager for Produce Marketing Association Australia-New Zealand 0950 Panel questions and answers 1000-1030 Morning tea 1030 Insights into exporting table grapes into Asian markets Peter Walsh, Victorian Minister for Agriculture and Food Security, Minister for Water 1050-1220 Session 2 Soil Management and Mineral Nutrition Moderator: Colin Gordon Department of Agriculture and Food, Western Australia, South Perth, WA, Australia 1050 Soilless table grape cultivation - A review Rosario Di Lorenzo, Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Palermo, Italy 1110 Soil management using no tillage and cover crops in a table grape vineyard in South-eastern Italy, (Puglia region) Giuseppe Ferrara, Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti - University of Bari ‘Aldo Moro’, Italy 1130 First results on soil management of organically produced ‘Midnight Beauty’ table grapes covered with plastic film in Apulia region Gianvito Masi, Consiglio per la Ricerca e la Sperimentazione in Agricoltura - Research Unit for Viticulture and Enology in Southern Italy, Turi, Italy 7th International Table Grape Symposium 3 PROGRAM 4 1150 Advancing ripening of Scarlet Royal grown in the desert region in California Carmen Gispert, University of California, Cooperative Extension, Indio, California, USA 1210 Panel questions and answers 1220-1320 Lunch 1320-1520 Session 3 Rootstocks, Breeding and Cultivar Improvement Moderator: Jennifer Hashim-Maguire AUSCAL Viticulture, Melbourne, Victoria, Australia 1320 Keynote Address Advanced Genetic Improvement Strategies: New vines for new times Mark Thomas, CSIRO Plant Industry, Urrbrae, South Australia, Australia 1350 New table grape varieties obtained in the breeding program by ITUM-IMIDA in Spain Juan Carreño, Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario, La Alberca, Murcia, Spain 1410 Developments in the Australian table grape breeding program Peter Clingeleffer, CSIRO Plant Industry, Urrbrae, South Australia, Australia 1430 Apulia Seedless: Description and effect of cultural practices Pietro Scafidi, Agriproject Group Australia Pty Ltd, Euston, NSW, Australia 1450 What can we learn from the table grape breeding program in Israel? Amnon Lichter, The Volcani Center, Bet Dagan, Israel 1510 Panel questions and answers 1520-1550 Afternoon tea 1550-1730 Session 4 Rootstocks, Breeding and Cultivar Improvement (Continued) Moderator: Allison Ferry-Abee University of California, California, USA 1550 Keynote Address Using novel genetics to breed unique new table grape varieties John Clark, Department of Horticulture/Plant Science, University of Arkansas, Fayetteville, Arkansas, USA 1620 Addressing challenges in the global development of proprietary varieties through applied varietal research Hovav Weksler, Sun World International, Bakersfield, California, USA 1640 Effect of rootstock on leaf nutrient composition of V. vinifera cultivars Superior Seedless and Red Globe María Beatriz Pugliese, INTA EEA Pocito, San Juan, Argentina 1700 Performance of Autumn King and Scarlet Royal table grapes on some standard and recently released rootstocks Matthew Fidelibus, Department of Viticulture and Enology, University of California, Davis, California, USA 1720 Panel questions and answers 1730 Closing remarks and housekeeping (nominations for 8ITGS close) 7th International Table Grape Symposium PROGRAM 1830-1900 Pre Dinner drinks and canapés, Quality Hotel Mildura Grand 1900-2330 Symposium Dinner, Quality Hotel Mildura Grand Ball Room (Dress: smart casual) Sponsored by Perfection Fresh Dinner MC: Jeff Scott, CEO ATGA Dinner entertainment: perceptionist Tom Berger, an entertaining blend of mystery, humour, psychology and intuition using total audience participation THURSDAY, 13 NOVEMBER 0730-1400 Day registration desk open (tea and coffee on arrival) 0830-1020 Session 5 Pest and Disease Management Moderator: Mark Krstic Australian Wine Research Institute, Melbourne, Victoria, Australia 0830 Welcome and housekeeping 0840 Keynote Address Identification and management of trunk diseases in Australia Mark Sosnowski, South Australian Research and Development Institute, Adelaide, South Australia, Australia 0910 Canker diseases in the Coachella Valley: Incidence and evaluation of management strategies Carmen Gispert, University of California, Cooperative Extension, Indio, California, USA 0930 Control of grapevine Powdery Mildew with the biofungicide Timorex Gold. Juan Cristobal Arroyo, Stockton Israel Ltd, Petach Tikva, Israel 0950 Effective control of fruit fly for market access using a systems management approach in table grapes David Oag, Queensland Department of Agriculture, Fisheries and Forestry, Stanthorpe, Queensland, Australia 1010 Panel questions and answers 1020-1050 Morning tea 1050-1300 Session 6 Plant Growth Regulators Moderator: Peter Clingeleffer CSIRO Plant Industry, Urrbrae, South Australia, Australia 1050 Understanding the control of grape berry ripening and developing opportunities for its manipulation Christopher Davies, CSIRO Plant Industry, Urrbrae, South Australia, Australia 1110 Effect of shade and gibberellic acid (GA3) on fruit set and final quality of Thompson Seedless and Crimson Seedless table grape cultivars - A field assay in South Portugal Sara Domingos, Universidade de Lisboa, Instituto Superior de Agronomia, Lisboa, Portugal 1130 Effects of PGR’s (GA3 and CPPU) and cane girdling on yield, quality and metabolic profile of cv. Italia table grape Giuseppe Ferrara, Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti - University of Bari ‘Aldo Moro’, Italy 7th International Table Grape Symposium 5 PROGRAM 6 1150 Effect of CPPU (N-(2-Chloro-4-Pyridinyl)-N’-Phenylurea) and a seaweed extract on Crimson Seedless grape quality Janéne Strydom, ARC Infruitec-Nietvoorbij, Stellenbosch, South Africa 1210 Evaluation of table grape colouration programs in global production areas Robert Fritts, Valent BioSciences Corporation, Clovis, California, USA 1230 Improving table grape colouring programs with s-abscisic acid (Protone™): the importance of application technology Schalk Reynolds, Philagro SA, Somerset West, South Africa 1250 Panel questions and answers 1300-1400 Lunch 1400-1605 Session 7 Table Grape Growing in Tropical/Subtropical Environments and Dormancy Moderator: David Oag Department of Agriculture, Fisheries and Forestry, Stanthorpe, Queensland, Australia 1400 Keynote Address Challenges and opportunities to growing table grapes in sub-tropical/tropical regions Patrícia Coelho de Souza Leão, Brazilian Agricultural Research Corporation, Petrolina, Brazil 1430 Comparative Transcriptomic study of bud dormancy in sub-tropical and Mediterranean climates Michael Considine, School of Plant Biology, University of Western Australia, Crawley, WA Australia 1450 Low temperature-dependent release from dormancy involves a transient oxidative burst in grapevines (Vitis vinfera) buds Karlia Meitha, School of Plant Biology, University of Western Australia, Crawley, WA Australia 1510 Influence of external dormancy release forcing factors on grape vine bud dormancy and the concomitant changes in bud respiration Yazhini Velappan, School of Plant Biology, University of Western Australia, Crawley WA Australia 1530 Control of grape bud dormancy release Etti Or, Department of Fruit Tree Sciences, Volcani Centre, ARO, Israel 1550 Panel questions and answers 1600 Closing remarks and housekeeping 1610-1810 Poster Session – includes drinks and canapés, marquee Mildura Arts Centre Sponsored by Sheehan Genetics Australia MC – Peter Clingeleffer, CSIRO Plant Industry, Urrbrae, SA, Australia Announcement of ‘Best Poster Award’ Voting for host of 8th International Table Grape Symposium Note – no symposium dinner tonight, please make own dinner arrangements 7th International Table Grape Symposium PROGRAM FRIDAY, 14 NOVEMBER 0730-1400 Day registration desk open (tea and coffee on arrival) 0830-1110 Session 8 General Viticulture and Vine Physiology Moderator: Matthew Fidelibus Department of Viticulture and Enology, University of California, Davis, California, USA 0830 Welcome and housekeeping 0840 Plastic rain covers affect canopy microclimate and fruit quality of table grapes Matthew Fidelibus, Department of Viticulture and Enology, University of California, Davis, California, USA 0900 Identification and characterisation of factors affecting development of size diversity among berries in a clusters of cv. Early Sweet Etti Or, Department of Fruit Tree Sciences, Volcani Center, ARO, Israel 0920 Irrigation strategy and vine performance of organic ‘Italia’ table grape grown in Apulia region (Southern Italy) Luigi Tarricone, Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Research Unit for Viticulture and Enology in Southern Italy, Turi, Italy 0940 A study on the factors involved with russet stains in Thompson Seedless table grapes Hovav Weksler, Department of Postharvest Science, The Volcani Center, Bet Dagan, Israel 1000 Causes and prevention of Thompson Seedless berry collapse Peter Clingeleffer, CSIRO Plant Industry, Urrbrae, South Australia, Australia 1020 The use of autofluorescence and imaging for phenological analysis of table grapes Amnon Lichter, Department of Postharvest Science, The Volcani Center, Bet Dagan, Israel 1040 Satellite-based assessments of irrigation water use by table grapes grown in the Robinvale district of SE Australia Des Whitfield, Department of Environment and Primary Industries, Tatura, Australia 1100 Panel questions and answers 1110-1140 Morning tea 1140-1335 Session 9 Postharvest Technologies Moderator: Don Luvisi University of California Cooperative Extension, Viticulture Advisor, Emeritus 1140 Sulfur dioxide in the berry: metabolism, inducible defences and insights Michael Considine, School of Plant Biology, The University of Western Australia, Crawley, Western Australia, Australia 1200 VapormateTM : applications as a fumigant for the table grape industry Swaminathan Thalavaisundaram, Linde Crop Sciences, North Ryde, Australia 1220 New techniques for postharvest application of SO2 on table grapes Eduardo Maldonado Araneda, Insumos Frutìcolas INFRUTA SA, Lampa, Santiago, Chile 1240 Alternative fumigation and cold treatment disinfestation methods Andrew Jessup, NSW Department of Primary Industries, Gosford, NSW, Australia 7th International Table Grape Symposium 7 PROGRAM 1300 Predicting rachis browning and quality loss in Vitis vinifera L. cv. Thompson Seedless during cool storage John Lopresti, Department of Environment and Primary Industries, Victoria, Australia 1320 Panel questions and answers 1330 Symposium closing remarks and announcement of host for 8ITGS 1335-1435 Lunch 1830-2230 River cruise, boarding ‘Mundoo’ from 1830 for a 1900 departure. Mildura Wharf, Hugh King Drive Sponsored by GrapeCo. SATURDAY AND SUNDAY, 15 - 16 NOVEMBER Post Symposium Technical Tour 0830-2200 Saturday - Mildura and Robinvale regions 0830-1500 Sunday - Mildura and local district area Dress: Please wear light-weight clothing, a wide-brimmed hat and sun protection cream. Sponsored by UVASYS, Netafim and R&D Viticultural Services Platinum sponsor Presented by Disclaimer The 7ITGS2014 Committee and the editors of this publication accept no responsibility or liability of any kind for any statement, opinion or other material contained in this publication. Abstracts published do not necessarily represent the opinion of the committee or founding partners. Articles and other comments represent the opinions of their respective authors and might contain mistakes of fact, hypotheses and other unsubstantiated material. Notwithstanding the mention of any products or services in this publication the committee gives no warranty or endorsement in respect to them. 8 7th International Table Grape Symposium Table of Contents Welcome to Mildura..................................................................................................................................................................................1 Symposium Program................................................................................................................................................................................3 Keynote speaker profiles.................................................................................................................................................................... 13 Richard Bennett................................................................................................................................................................................................13 Dr Patricia Coelho de Souza Leão..............................................................................................................................................................13 Professor John R. Clark...................................................................................................................................................................................14 Professor Gregory V. Jones...........................................................................................................................................................................14 Dr Mark Sosnowski..........................................................................................................................................................................................15 Dr Mark R. Thomas...........................................................................................................................................................................................15 Oral Presentation Abstracts Wednesday 12 November 2014...................................................................................... 17 Session 1. Table grape production and marketing: future challenges and opportunities................................................17 Climate change, agriculture and global table grape production........................................................................................................17 Management of food safety issues in fresh fruit production ..............................................................................................................20 Session 2. Soil management and mineral nutrition...........................................................................................................................24 Soilless table grape cultivation - a review................................................................................................................................................24 Soil management using no tillage and cover crops in a table grape vineyard in southeastern Italy (Puglia region)................26 First results on soil management of organic Midnight Beauty® table grapes covered with plastic film in Apulia region.........28 Advancing ripening of Scarlet Royal grown in the desert region in California.................................................................................33 Session 3. Rootstocks, breeding and cultivar improvement..........................................................................................................35 Advanced genetic improvement strategies: New vines for new times..............................................................................................35 New table grape varieties obtained in the breeding program by ITUM-IMIDA in Spain.................................................................37 Developments in the Australian table grape breeding program .......................................................................................................39 Apulia Seedless: Description and effect of cultural practices...............................................................................................................43 What can we learn from the table grape breeding program in Israel?...............................................................................................47 Session 4. Rootstocks, breeding and cultivar improvement (Continued)................................................................................48 Using novel genetics to breed unique new table grape varieties ......................................................................................................48 Addressing challenges in the global development of proprietary varieties through applied varietal research.........................51 Effect of rootstocks on leaf nutrient composition of Vitis vinifera cvs. Superior Seedless and Red Globe....................................53 Performance of Autumn King and Scarlet Royal table grapes on some standard, and more recently released, rootstocks ...56 7th International Table Grape Symposium 9 Oral Presentation Abstracts Thursday 13 November 2014........................................................................................... 59 Session 5. Pest and disease management.............................................................................................................................................59 Identification and management of trunk diseases in Australia ..........................................................................................................59 Canker diseases in the Coachella valley: Incidence and evaluation of management strategies...................................................60 Control of grapevine powdery mildew with the natural biofungicide Timorex Gold .....................................................................62 Effective control of fruit fly for market access using a systems management approach in table grapes.....................................65 Session 6. Plant growth regulators...........................................................................................................................................................68 Understanding the control of grape berry ripening and developing opportunities for its manipulation...................................68 Effect of shade and gibberellic acid (GA3) on fruit set and final quality of Thompson Seedless and Crimson Seedless table grape cultivars - A field assay in South Portugal..........................................................................................70 Effects of PGRs (GA3 and CPPU) and cane girdling on yield, quality and metabolic profile of cv Italia table grape...................74 Effect of CPPU (N-(2-chloro-4-pyridinyl)-N’-phenylurea) and a seaweed extract on Crimson Seedless grape quality .............76 Evaluation of table grape colouration programs in global production areas...................................................................................80 Improving table grape colouring programs with s-abscisic acid (Protone™): the importance of application technology.......82 Session 7. Table grape growing in tropical/subtropical environments and dormancy......................................................84 Challenges and opportunities to growing table grapes in sub-tropical/tropical regions...............................................................84 Comparative transcriptomic study of bud dormancy in sub-tropical and Mediterranean climates.............................................85 Low temperature-dependent release from dormancy involves a transient oxidative burst in grapevine (Vitis vinifera) buds.......................................................................................................................................................................................87 Influence of external dormancy release forcing factors on grapevine bud dormancy and the concomitant changes in bud respiration.........................................................................................................................................................................................91 Control of grape bud dormancy release .................................................................................................................................................93 Oral Presentation Abstracts Friday 14 November 2014.................................................................................................. 94 Session 8. General Viticulture and Vine Physiology............................................................................................................................94 Plastic rain covers affect canopy microclimate and fruit quality of table grapes..............................................................................94 Identification and characterisation of factors affecting development of size diversity among berries in a clusters of cv. Early Sweet..........................................................................................................................................................................................96 Irrigation strategy and vine performance of organic ‘Italia’ table grape grown in Apulia region (Southern Italy)......................97 A study on the factors involved with russet stains in Thompson Seedless table grapes............................................................. 101 Causes and prevention of Thompson Seedless berry collapse......................................................................................................... 102 The use of autofluorescence and imaging for phenological analysis of table grapes.................................................................. 105 Satellite-based assessments of irrigation water use by table grapes grown in the Robinvale district of SE Australia............ 106 Session 9. Postharvest technologies..................................................................................................................................................... 109 Sulfur dioxide in the berry: metabolism, inducible defences and insights..................................................................................... 109 VapormateTM application in a commercial chamber for controlling table grapes pests ............................................................. 112 New techniques of postharvest application of SO2 on table grapes............................................................................................... 114 Alternative fumigation and cold treatment disinfestation methods .............................................................................................. 118 Predicting rachis browning and quality loss in Vitis vinifera L cv ‘Thompson Seedless’ during cool storage............................ 120 10 7th International Table Grape Symposium Poster Presentations Abstracts Thursday 13 November 2014..................................................................................123 Changes in the table grape industry – challenges for a sulphur dioxide pad manufacturer...................................................... 123 Timorex Gold - a new natural bio-fungicide for the control of sour rot complex and grey mould in table grapes ................ 124 Agronomic and qualitative performances of some table grape Dalmasso crosses (Vitis vinifera L.) grown in Piedmont (NW of Italy)............................................................................................................................................................................. 127 Inconsistent yielding between years is a threat to the sub-tropical table grape industry in Queensland................................ 130 Performance of table grape JD 874 grafted onto different rootstocks in two regions of São state, Brazil................................ 132 Ethephon and abscisic acid for improving colour of ‘Crimson Seedless’ table grape in the Vale do São Francisco, Northeastern of Brazil in 2012 growing season................................................................................................................................... 134 Moving in on mealybugs in Western Australian table grape vineyards.......................................................................................... 136 Effects of box liner perforation area on methyl bromide diffusion into table grape packages during fumigation................ 139 Postharvest conservation of ‘Crimson Seedless’ grapes as influenced by ethephon and abscisic acid application on field.... 141 Effects of Kelpak® Ecklonia maxima seaweed product on quality and yield of red globe table grape in Sicily, Italy............... 143 Policy assessment for the table grape production in southern Italy................................................................................................ 145 Effect of rootstock on growth and nutritional status of Thompson Seedless grown under soils with different air content.... 146 Use of ABA to improve the colour of Red Globe table grapes in the San Juan region, Argentina.............................................. 147 Potential to enhance fruit quality of table grapes with potassium sorbate and cincturing........................................................ 149 Temperature and light regimes under different plastic rain covers................................................................................................. 151 Flame Seedless cluster quality according to bud position ............................................................................................................... 153 Development of ProtoneTM SL (10% s-ABA) for colouration of red seedless table grapes in Europe......................................... 154 Inheritence of terpenoids in F1 population of ‘Jingxiu’ and ‘Xiangfei’ grape.................................................................................. 158 Making decisions in table grape production with benchmarking data.......................................................................................... 162 Prospecting for fungicide activity on wild mushrooms extracts against gray and blue mould of table grapes ..................... 165 The effects of elevated CO2 and a rise in air temperature on commercially grown grapevines ................................................. 168 Effect of NAA on the sucrose metabolism and expression of some related genes in grape fruit............................................... 171 Effects of natural auxin-based Ecklonia maxima seaweed product on reduction of postharvest berry drop in table grape cv. Thompson Seedless................................................................................................................................................................. 172 Abscisic acid (S-ABA) and sucrose effects on skin colour, anthocyanin content and antioxidant activity of ‘Crimson Seedless’ grape berries............................................................................................................................................................ 174 Fumigation and cold treatment disinfestation methods................................................................................................................... 176 Author Index............................................................................................................................................................................................180 Notes.............................................................................................................................................................................................................182 Notes.............................................................................................................................................................................................................183 Notes.............................................................................................................................................................................................................184 7th International Table Grape Symposium 11 As the leader in developing and commercializing innovative biorational solutions to maximize crop potential, Valent BioSciences partners with table grape growers to deliver the highest quality produce to retailers around the world. For more information about our award-winning line of sustainable biorational products, visit www.valentbiosciences.com Valent BioSciences is an ISO 9001:2008 Certified Company ©2014 Valent BioSciences Corporation. 12 7th International Table Grape Symposium Keynote speaker profiles KEYNOTE SPEAKERS Richard Bennett Dr Patricia Coelho de Souza Leão Richard Bennett is the technology manager for the Produce Marketing Association (PMA) Australia-New Zealand, based in the Goulburn Valley, Victoria. The activities of this role revolve around communicating the latest information on food safety, science and technology to PMA A-NZ members and the broader industry. Patricia Coelho de Souza Leão is a Agronomy Engineering graduate from Universidade Federal Rural de Pernambuco (1993). She has a Master’s in Agronomy (Plant Breeding and Genetics) from Universidade Estadual Paulista Júlio de Mesquita Filho (1999) and Ph.D. in Genetics and Breeding, from the Universidade Federal de Viçosa (UFV) and University of California, Davis (2008). The objective is to increase knowledge of business best practices and improve food safety culture and performance. In this way, consumer and supply chain trust and confidence in the integrity of fresh produce will be maximised. Themes include quality assurance, food safety, environmental management, product standards and specifications, product identification and traceability, business continuity, compliance issues and crisis management. In addition, the role includes the technical functions of the newly established Fresh Produce Safety Centre, an organisation dedicated to food safety outreach, education and research. Since 1994 Patricia has worked as a researcher at the Brazilian Agricultural Research Corporation, Embrapa Semiarid, in Petrolina, PE, Brazil where her research projects focus on grape breeding and crop science working on germplasm evaluation, rootstocks, improvement of new varieties and canopy management. Patricia has authored or co-authored 32 papers in periodicals, 21 book chapters and more than 100 abstracts in scientific congress and symposium. Richard has worked in numerous aspects of horticulture including in the nursery, seed and fruit processing industries, and as an industry development officer, trainer, agronomist and executive officer for a number of fruit grower associations. He has been heavily involved in food safety and related issues for over 15 years. He has developed and implemented Approved Supplier Programs and implemented SQF 2000 and Freshcare in fruit, vegetable, nut and wine grape businesses. Richard has qualifications in orchard management, applied science, agribusiness and food safety. 7th International Table Grape Symposium 13 KEYNOTE SPEAKERS Professor John R. Clark Professor Gregory V. Jones John Clark is a university professor of horticulture at the University of Arkansas. His research responsibilities are his primary appointment, where he directs the University’s Division of Agriculture fruit breeding program and teaches in the areas of fruit production and plant breeding. He has worked in the Arkansas program for 34 years and has released 50 commercial varieties. Crops he works with include blackberries, table grapes, muscadine grapes, blueberries, and peaches/nectarines. His research activities are carried out in Arkansas, several US states, and various countries in the world. Gregory Jones is a professor and research climatologist in the Department of Environmental Studies at Southern Oregon University who specialises in the study of climate structure and suitability for viticulture, and how climate variability and change influence grapevine growth, wine production and quality. He holds a Bachelor of Arts and Ph.D. from the University of Virginia in Environmental Sciences with a concentration in the Atmospheric Sciences. His dissertation was on the climatology of viticulture in Bordeaux, France with a focus on the spatial differences in grapevine phenology, grape composition and yield, and the resulting wine quality. A native of Mississippi, John has Bachelor of Science and Masters of Science degrees from Mississippi State University and a PhD from the University of Arkansas. His work in table grapes has involved hybridising American species-derived grapes with Vitis vinifera, to combine increased flavour, winter hardiness, fruit cracking resistance, components of disease resistance, and broader adaptation from V. labrusca with the high-quality fruit attributes of V. vinifera. The program in Arkansas has been ongoing for 50 years, the longest effort thus far with a focus on table grapes of this type. The program has released 10 varieties, primarily intended for local marketing in the Midwest and eastern United States. For over 10 years John has worked in cooperation with International Fruit Genetics in California, blending the traits from the Arkansas developments with commercial table grapes in California. Products from this effort are released by IFG and are now in the US market, providing for unique table grapes not seen by American consumers prior. These unique flavours combined with excellent skin and texture characteristics plus diversified shapes have the potential to have substantial impact on American and world markets. 14 7th International Table Grape Symposium Gregory’s teaching and research interests include meteorology, climatology, hydrology, and agriculture; phenology of plant systems; biosphere and atmosphere interactions; climate change; and quantitative methods in spatial and temporal analysis. He conducts applied research for the grape and wine industry in Oregon and has given hundreds of international, national, and regional presentations on climate and wine-related research. He is the author of numerous book chapters, including being a contributing author to the 2008 Nobel Peace Prize winning Intergovernmental Panel on Climate Change Report, and other reports and articles on wine economics, grapevine phenology, site assessment methods for viticulture, climatological assessments of viticultural potential, and climate change. He was named in Decanter Magazine’s 2009 Power List representing the top 50 most influential people in the world of wine, named the Oregon Wine Press’s 2009 Wine Person of the Year, and has been in the top 100 most influential people in the US wine industry in 2012 and 2013 (www.intowine.com). KEYNOTE SPEAKERS Dr Mark Sosnowski Dr Mark R. Thomas Mark Sosnowski leads the Plant Health and Biosecurity science program at the South Australian Research and Development Institute (SARDI). After graduating with a Bachelor of Agricultural Science from the University of Adelaide (UA), he commenced working for SARDI in 1997 and went on to complete a PhD in 2002, studying the epidemiology and management of blackleg disease of canola at UA. Mark Thomas is a Senior Principal Research Scientist at CSIRO and has been conducting grapevine research since 1990. He received the P. L. Goldacre Medal of the Australian Society of Plant Physiologists in 1994 and has served on a number of international scientific grapevine committees and was Chairman of the International Grape Genome Program from 20022008. Since 2003, Mark has been responsible for research on managing Eutypa dieback disease in grapevines at SARDI, collaborating with colleagues in the US, Spain and Canada. He is currently responsible for research programs on management of Eutypa and Botryosphaeria dieback diseases in both Australia and New Zealand. As the current Australasian regional representative on the International Council for Grapevine Trunk Diseases, Mark will convene the upcoming International Workshop on Grapevine Trunk Diseases in Australia. Mark developed the DNA typing method that is currently used throughout the world for identifying grapevine cultivars and his grapevine research has been published in a number of high quality research journals including Nature. His team was also responsible for developing rapid forward and reverse genetic approaches in grapevine using a novel grapevine form known as the microvine. In addition, Mark manages a biosecurity research program focussing on impact management of exotic grapevine pathogens in collaboration with Cornell University, US. He is an Affiliate Senior Lecturer at UA and supervises numerous postgraduate students in a range of plant pathology projects. Mark has a long standing interest in grapevine improvement and the identification of genes and alleles responsible for traits of economic importance to the grape industry. Mark has a decade of grapevine disease research experience in Australia and draws from his extensive international experience and collaboration to provide industry with the latest information for effective management of trunk diseases. 7th International Table Grape Symposium 15 20 years of trusted, proven success Reliable performance Low residues Member organisations: · Sunraysia Table Grape Growers Association · Robinvale Table Grape Growers Association · Table Grape WA Inc. · Table Grapes Qld UVASYS is a plastic laminated sulphur dioxide sheet with predictable & consistent emission rates for maximum protection of your grapes 33 Madden Avenue, Mildura, Victoria 3500, Australia Telephone: +613 5021 5718 Facsimille: +613 4009 0038 Email: [email protected] www.uvasys.com www.australiangrapes.com.au PROUD MARKETERS OF 16 7th International Table Grape Symposium www.costagroup.com.au Oral Presentation Abstracts WEDNESDAY 12 NOVEMBER 2014 ORAL SESSION 1 Session 1. Table grape production and marketing: future challenges and opportunities Keynote address Climate change, agriculture and global table grape production Gregory V. Jones Department of Environmental Studies, Southern Oregon University, 1250 Siskiyou Blvd, Ashland, Oregon, 97520, USA Tel: +1 541 552 9192, Email: [email protected] Background and Aims Agricultural production is environmentally sensitive being highly influenced by changes in climate, soil water and nutrition, and land use practices. From a climate perspective, agriculture is extremely vulnerable to climate change as most crop systems have been optimised to ﬁt a given climate niche allowing for economically sustainable quality and production. These climatic niches range from fairly broad conditions suitable for crops such as wheat or corn, to more narrow conditions suitable for specialty crops such as grapevines. Potential agricultural responses to changing climates reﬂect the interactions between temperature, water availability and timing, increasing soil salinity and nutrient stresses, and increasing carbon dioxide concentrations. As such, understanding agricultural impacts from climate change necessitates integrated information and research examining the combined effects of these and other factors. This presentation will examine the overall state of the climate today and discuss the role that historic and future climates have on agriculture in general. In addition, the work will detail how climate change and variability impact growing grapes for both wine and fresh fruit production – including drought frequency and timing, heat stress events, and the lack of chilling in warm to hot climate regions – providing insights into the potential impacts of projected changes in growing conditions worldwide. Discussion Human interactions within earth’s environment have brought significant changes, producing a situation in which we now face some of the most complex collection of ecological problems in our history. Driven by population growth and often ecologically unsustainable processes these problems include an increasingly less predictable and stable climate and a wide range of interrelated social, environmental, and economic problems. Compounded by growing water scarcity, deforestation, species extinction, and ocean acidification, our ability to function as a species is challenged more than ever before (IPCC, 2013). Climate is at the forefront of these issues as it presents a very complex, highly variable, and pervasive factor in our natural earth and human-based systems. From controlling vegetation patterns and geological weathering characteristics to influencing water resources and agricultural productivity, climate is at the heart of the delicate equilibrium that exists on earth. While it is clear from historical evidence that changing climates are a part of the earth’s natural adjustments to both internal and external forces (e.g., volcanic eruptions and solar variability), more and more evidence is pointing to increasing human impacts on our climate (IPCC, 2013). Processes such as desertification, deforestation, and urbanisation by which the global energy balance is disrupted, and changes in atmospheric composition that enhance the greenhouse effect beyond its natural equilibrium demonstrate that our role in changing the climate is increasing. 7th International Table Grape Symposium 17 Agriculture represents probably one of the most complex aspects of our human-environmental interactions whereby we need increasingly more productive systems to feed our growing population, yet aspects of doing so have, and will likely continue to, exacerbate the problems. As such agriculture has both a role in producing some of our challenges, but more importantly has been increasingly asked to develop sustainable practices that reduce our vulnerability and increase our adaptive capacity in the face of global change (Diffenbaugh et al., 2011). ORAL SESSION 1 Today, as in the past, climate is clearly one of the most important factors in the success of all agricultural systems, influencing whether a crop is suitable to a given region, largely controlling crop production and quality, and ultimately driving economic sustainability (Jones et al., 2012). While decisions about what to crop to grow commercially are largely driven by regional history and tradition, they are also influenced by regional to international economics. However, both tradition and economics are ultimately driven by the ability to grow the crop sustainably within a given climate (White et al., 2009). From broadacre crops such as wheat, rice, corn, and soybeans to specialty crops such as fruits and vegetables, tree nuts, dried fruits, and coffee; they all have strong ties to global to regional climates. While broadacre crops are clearly more important as global food sources, specialty crops present unique sensitivities to climate that have made them especially interesting to researchers examining global change. This fact is never more evident than with wine and table grape production where climate is arguably the most critical environmental aspect in ripening fruit to its optimum quality to produce a marketable product (Jones, 2014). As a specialty crop, both wine and table grape production typically occurs over relatively narrow geographical and climatic ranges (Jones, 2006). While historically associated with Mediterranean climates, viticulture has spread throughout much of the world with wine grapes found as far north as in Scandinavia (helped by a warming climate), on east coasts of continents (e.g., China, Japan, and the eastern US) and near the equator where two crops per year are produced (e.g., Brazil) (Jones et al., 2012). Table grape production has also spread throughout the drier subtropical climates with warm to hot and dry summers (e.g., China, Turkey, Brazil, India, etc.). The broader bounds for wine and table grape production occur in climates where the growing season temperatures averages 13-24°C average growing season temperatures (Jones, 2006). However, table grape production is typically more suited to climates where growing season average temperatures range from 17-24°C and where water availability for irrigation is readily available. Research on climate trends and future projections for table grape production is limited. However, recent research on aspects of global environmental change on wine grape production reveals significant changes but also many unknowns (Fraga et al., 2012). From a general climate perspective, wine regions worldwide have seen changes in average climate structure producing warmer and longer growing and dormant periods (Jones et al., 2005a). Growing season temperatures in many of the best wine producing regions in the world warmed 1.3°C during 19502000. However, the warming was not uniform across all regions with greater magnitudes in the western US and Europe and less warming in Chile, South Africa, and Australia. Also trends between day and night temperatures vary by region, with some seeing much more significant warming at night and others seeing more heat stress events through higher daytime temperatures (Nemani et al., 2001; Jones et al., 2005b). In addition to warmer growing seasons with greater heat accumulation, many of the world’s wine regions have experienced a decline in frost frequency and shifts in the timing of frosts (Jones, 2005; Donat et al., 2013). A comprehensive global assessment of 27 core indices that define the frequency or severity of extreme of temperature and precipitation events (Peterson, 2005) was conducted over 1951-2011 worldwide (Donat et al., 2013). The results show that minimum temperature extremes have been warming at 2-4 times the rate of maximum extremes, resulting in a decline in the diurnal temperature range and a reduction in dormant season chilling. Likewise, the percentage of days with temperatures in the lower 10th percentile has declined while the percentage in the upper 90th percentile has increased. During this period the length of the growing season has increased, while frost days (< 0°C) and cold spells (consecutive cold days) have declined and warm nights (Tmin > 20°C), warm days (Tmax > 25°C), and warm spells (consecutive warm days) have increased. However, cold extremes still occur and there is some evidence that acclimation to more benign conditions can make both the plant system and human readiness for such events more susceptible to their occurrence (Gu et al., 2008). For precipitation, the annual contribution from very and extremely wet days (> 95th and 99th percentile) has increased significantly while the number of consecutive dry days (< 1 mm) has declined globally (Donat et al., 2013). Depending on the underlying emission scenario, climate models predict continued increases in global temperatures of 1.3°C to 4.8°C by the end of this century (IPCC 2013). Furthermore, observations and modelling have shown that changes in climate have not and will not likely be manifested in just changes in the mean, but also in the variance where there are likely to be more extreme heat occurrences, but still swings to extremely cold conditions (IPCC, 2013). Therefore, even if average climate structure gets better or more suitable in some regions, variability will still 18 7th International Table Grape Symposium be very evident and possibly even more limiting than what is observed today (Schär et al., 2004). Work over the last three decades using model projections show that the observed warming trends in wine regions worldwide are predicted to continue. Globally, Jones et al., (2005a) found that mean growing season temperatures could warm by an average 2°C in 27 of the world’s top wine producing regions by 2049. Other research as detailed significant historical changes in drought frequency and timing, that likely will be exacerbated in many regions worldwide (IPCC, 2013). ORAL SESSION 1 Overall, table grapes are a specialty crop with moderate climatic sensitivity whereby sustainable production is achieved across a fairly narrow geographic range. In addition, table grapes are grown largely in mid-latitude to subtropical regions that are prone to moderate to high climatic variability that influences productivity. The projected rate and magnitude of future climate change will likely bring about numerous potential impacts for the table grape industry, including – added pressure on increasingly scarce water supplies, additional changes in growth timing, disruption or alteration of grape composition, and potential spatial changes in viable grape growing regions. While uncertainty exists in the exact rate and magnitude of climate change in the future, it would be advantageous for the table grape industry to be proactive in assessing the impacts, invest in appropriate plant breeding and genetic research, be ready to adopt suitable adaptation strategies, be willing to alter varieties and management practices or controls, or mitigate fruit quality differences by developing new technologies. References IPCC. 2013. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Eds. Stocker TF, Qin D, Plattner G-K, lignor M, Allen SK, Boschung J, NaueIs A, Xia Y, Bex V, Midgley PM]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. 1535 pp. Diffenbaugh NS, White MA, Jones GV, and Ashfaq M. 2011. Climate adaptation wedges: a case study of premium wine in the western United States. Environmental Research Letters, 6(024024). doi:10.1088/1748-9326/6/2/024024. Donat MG, Alexander LV, Yang H, Durre I, Vose R, Caesar J. 2013. Global Land-Based Datasets for Monitoring Climatic Extremes. Bulletin of the American Meteorological Society 94: 997–1006. Fraga H, Malheiro AC, Moutinho-Pereira, J. and J.A. Santos. 2012. An overview of climate change impacts on European viticulture. Food and Energy Security 1(2): 94-110. Gu L, Hanson PJ, Post WM, Kaiser DP, Yang B, Nemani R, Pallardy SG, Meyers T. 2008. The 2007 eastern US spring freezes: Increased cold damage in a warming world? BioScience, 58: 253–262. Jones GV. 2006. Climate and Terroir: Impacts of Climate Variability and Change on Wine. In: Fine Wine and Terroir - The Geoscience Perspective. Macqueen, R.W., and Meinert, L.D., (eds.), pp. 203-216. Geoscience Canada Reprint Series Number 9, Geological Association of Canada, St. John’s, Newfoundland, 247 pages. Jones GV, Reid R, Vilks, A. 2012. Climate, Grapes, and Wine: Structure and Suitability in a Variable and Changing Climate pp 109-133 in The Geography of Wine: Regions, Terrior, and Techniques, edited by P. Dougherty. Springer Press, 255 pp. Jones GV, White MA, Cooper OR, Storchmann K. 2005a. Climate Change and Global Wine Quality. Climatic Change 73(3): 319-343. Jones GV, Duchene E, Tomasi D, Yuste J, Braslavksa O, Schultz, H, Martinez, C, Boso S, Langellier F, Perruchot C, Guimberteau G. 2005b. Changes in European Winegrape Phenology and Relationships with Climate, XIV International GESCO Viticulture Congress, Geisenheim, Germany, 23-27 August, 2005. 875 pp. Vol.1 (23.0-27.8): 55-62. Nemani RR, White MA, Cayan DR, Jones GV, Running, SW, and Coughlan JC. 2001. Asymmetric climatic warming improves California vintages. Climate Research, Nov. 22 19(1): 25-34. Schär C, Vidale PL, Lüthi D, Frei C, Häberli C, Liniger M, Appenzeller C. 2004. The role of increasing temperature variability in European summer heat waves. Nature 427, 332-336. White MA, Whalen P, Jones, GV. 2009. Land and Wine. Nature Geoscience 2: 82-84. 7th International Table Grape Symposium 19 Keynote address Management of food safety issues in fresh fruit production Richard R Bennett ORAL SESSION 1 Produce Marketing Association (PMA) Australia-New Zealand Ltd, PO Box 1968, Shepparton, Victoria, 3632, Australia. Tel: +61 429 329 731, Email: [email protected] Background and Aims Food safety is an important global issue for the fresh produce industry. Physical contaminants, human pathogens and agricultural chemicals have and continue to cause illness and injury to consumers. The World Health Organisation estimates that foodborne and waterborne diarrhoeal diseases kill an estimated 2.2 million people annually, most of whom are children (WHO, 2013). In Australia, an estimated 5.4 million cases of foodborne disease occur annually, costing an estimated $1.2 billion per year (Hall et al., 2012). OzFoodNet – the Australian Government’s foodborne disease surveillance system – considers that most cases manifest as mild self-limiting gastroenteritis and that only 20% of affected people take their illness to a medical practitioner (OzFoodNet, 2012). Although OzFoodNet also contends that many of these illnesses are preventable, neither regulatory, customer nor self-interest drivers appear effective in reducing the issue, which continues to grow. Against this background, fresh produce industries around the globe, in developed and developing nations, have been implementing Hazard Analysis and Critical Control Point (HACCP) based systems and Good Agricultural Practices (GAPs) in order to manage food safety hazards. However, massive gaps in adoption, and in the quality of adoption, continue to exist. This paper aims to use Australia as a case study of the emergence of food safety management, analysis of food safety issues in fresh produce, a focus on table grape issues and an introduction to crisis management. Results and Discussion 1. The food safety operating environment It is important to understand where the management of food safety fits in the overall value chain, to identify the competing and contributing influences that shape the delivery of safe food to consumers. Food safety needs to be seen in the context of a rapidly evolving product mix that caters to the changing demands of consumers. Fresh produce is increasingly available in a mix of ingredients, and not necessarily just other produce items. Convenient meal solutions is the current growth category, and the food service sector accounts for approximately 17% of Australian fresh fruit and vegetable domestic market share (Spencer and Kneebone, 2012). Consumers are expecting their fresh produce in whatever format to be available from an increasing range of retail and food service outlets, they expect greater shelf life if they take it home and they expect it to be healthy and wholesome. The ongoing drive to meet these expectations at a price that is competitive with other meal solutions is a constant challenge for the value chain. Safety of this food is a given and is afforded a high priority by consumers. The Roy Morgan Research Group interviewed 15,471 Australian grocery buyers aged 14 plus in 2013 and concluded that “food safety at the supermarket is important to more Australian grocery buyers than proximity to home, good value, trading hours or the quality and range of fresh fruit and vegetables.” (Roy Morgan Research, 2013). Supply chain complexity not only includes the range of products combined as ingredients but also their varying origin. Greater availability of imported ingredients emphasises the need for detailed product identification and traceability. Building this integrity into quality assurance systems is also challenging. Again, there is an expectation that others in the value chain have the same knowledge, attitudes, skills and aspirations (KASA) as the final supplier needs and the consumer demands. This is not always the case. 20 7th International Table Grape Symposium Finally, it comes down to the grower. Faced with a growing burden of customer and regulatory requirements, and needing to be hands-on horticulturist, business manager, IT savvy, marketer, mechanical engineer and dangerous goods handler, the grower must recognise that most food safety issues originate on farm. Some basic microbiology has also become a prerequisite for the job. 2. Development of quality assurance in fresh produce ORAL SESSION 1 HACCP is a logical science-based approach – analyse a product to identify the hazards to 100% compliance with an agreed specification, identify the critical points in the manufacturing process where those hazards can be controlled, and apply the appropriate measures to build out faults. The alternative is to continue to manufacture variable quality goods and then sort out the good from the bad by inspecting and testing the final products. This is wasteful and expensive. The foundation of food safety management, HACCP, has its food industry origins in the United States in the 1960s when the National Aeronautics and Space Administration (NASA) wanted to manage the risk of contaminated food for space flights. HACCP entered mainstream Australian fresh produce supply in the mid-1990s when major retailers first approached their direct suppliers – wholesalers and larger packers - with compliance deadlines. Although a business can be certified to HACCP alone, schemes such as the Woolworths Vendor Quality Management Standard and the Safe Quality Food (SQF) 2000 Code included additional requirements from ISO9000 quality management standards. In time, direct suppliers set about ensuring that their suppliers became approved to supply into the supermarket system. How they went about this varied markedly, from requiring only recent agrichemical application records to SQF2000 certification. An informal network of horticulture specialists with an interest in food safety put together a risk-based approach to developing an approved supplier program, to lead and inform industry in a more intuitive way than other approaches. While appearing prescriptive in approach, Developing an Approved Supplier Program for Fresh Produce was actually based on HACCP principles and was widely acclaimed. It directly led to the development of the Freshcare Food Safety and Quality Code of Practice, which was launched in 2000. This was followed by the Guidelines for On-Farm Food Safety for Fresh Produce, designed to provide the next level of detail around actual implementation. This document became the major reference for QA facilitators, trainers and auditors. It is now estimated that there are over 8,000 third party certifications of horticultural businesses in Australia (Howe, 2011). However, given that a number of businesses are direct suppliers to more than one retailer, Coles and Woolworths in particular, and would therefore require more than one certification, the actual number of certified businesses is estimated to be 6,200. As part of its evaluation whether to implement a Primary Production and Processing Standard for Horticulture, effectively a regulation requiring all horticulture businesses to implement a food safety system, Food Standards Australia New Zealand (FSANZ) estimated that those 8,000 certifications represented between 70-80% of horticultural production (FSANZ, 2014). This is cited as one of the reasons why FSANZ decided to abandon Proposal 1015 in favour of other measures. 3. Attribution of food safety issues Despite the implementation of food safety systems throughout the world, food safety issues continue to arise. One needs to consider that there are three types of contaminants that need to be managed – physical, chemical and microbiological. Physical contaminants include foreign objects from the environment (sticks, stones, etc), from equipment and containers (nails, glass, shavings) and from people (jewellery, adhesive dressings). Chemical contaminants are usually pesticides, heavy metals, lubricants or cleaners. Microbiological hazards are the human pathogens such as Salmonella, Listeria, E. coli, and Hepatitis A (DAFF, 2004). The contaminant with the highest profile is microbiological, thanks to a number of internationally well publicised outbreaks of foodborne illness and multiple deaths, for example: • • • Spinach, E. coli O157:H7, USA, 2006, over 4,000 illnesses and four deaths, Fenugreek seed sprouts from Egypt, E. coli O104:H4, 2011, 3,816 sickened and 54 deaths principally in Germany, Cantaloupe (rockmelon), Listeria monocytogenes, USA, 147 hospitalisations and 33 deaths. 7th International Table Grape Symposium 21 Microbiological contamination is likely to be more prevalent in developing countries with generally poorer hygiene and food safety standards but an absence of data makes this difficult to quantify. We can, however, see how fresh produce compares with other food types from the thorough surveillance data collected by the Centers for Disease Control and Prevention (CDC) in the USA. ORAL SESSION 1 The CDC studied 4,589 foodborne disease outbreaks between 1998 and 2011 where the illness could be attributed to a specific food category. Produce (six food categories – Fruits-Nuts, Fungi, Leafy vegetables, Root vegetables, Sprout vegetables, Vine-Stalk vegetables) accounted for 46% of all illnesses. Leafy vegetables was the highest individual category at 23% (CDC, 2013). In Australia, a compilation of food safety and related incidents since 2000 that have had the potential to cause reputational harm to the produce industry indicates that 50% of incidents are microbiological and a further 33% are related to pesticides (Bennett, 2014). Of 144 incidents, six mentioned table grapes. Four of these related to pesticide residues, one to table grape storage and one to physical contamination (spiders). Pesticide residue coverage was mostly spill-over of the US-based Environmental Working Group “Dirty Dozen” coverage. Not surprising, microbiological contamination did not feature. While contamination from harvest and postharvest handling equipment and workers is a possibility, table grapes should not come into contact with soil, there would be minimal pre-harvest water contact and no postharvest water contact. This equals low risk. Residues feature above average and are certainly a sensitive issue with Australian table grape consumers. Following the November 2012 launch of the Australian Table Grape Facebook page, a small number of consumers were quick to use the opportunity to question agrichemical and sulphur dioxide use by growers (Sinclair, D. pers comm. 2013). A response was prepared but this is an issue that needs greater attention. 4. Crisis Management Risk management and business continuity are contemporary priorities for successful businesses. The consolidation of supply chains horizontally and vertically and the concentration of supply to fewer and bigger retail and food service customers only serves to magnify the business risks. Contemporary quality assurance includes the need to formalise crisis management. Horticulture Australia, through its Across Industry Program, launched its Horticulture Industry Crisis Management Guidelines V1.0 in 2010. This initiative recognised that although much of the industry had adopted quality assurance as the most direct method of preventing food safety incidents, domestic and international experience suggests that incidents will still occur. The industry peak bodies in particular were not well placed to assist businesses respond and recover from a food safety incident but would be inextricably engaged should such an incident occur. A number of those peak industry bodies have now used the industry guidelines to develop their own crisis management plans and many businesses have accessed the guidelines to develop their own plans. The guidelines are not exclusively for food safety and can include natural disaster, work health and safety, fraud, sabotage and other crisis-stimulating events. Significance of the Study Management of food safety is a modern business imperative. Consumers, customers, regulators and businesses themselves have an interest in ensuring that all horticultural businesses produce safe food 24/7/365. To achieve this requires affective systems based on international standards, effectively implemented and competently audited. As consumers demand more complex but healthy and convenient meal solutions, the integrity requirements of fresh fruit and vegetables will only increase. Horticultural products already feature disproportionately high in foodborne illness so there is much work to be done, including the need for crisis management when things do go wrong. Acknowledgements This work was undertaken by the author as part of his Product Integrity Manager role at Horticulture Australia from 2001-2014, and continued in his Technology Manager role at PMA Australia-New Zealand Ltd and the Fresh Produce Safety Centre since February 2014. The Fresh Produce Safety Centre is financially supported by Voluntary Contributions from industry and matching funds from the Australian Government through Horticulture Australia. 22 7th International Table Grape Symposium References Bennett RR. 2007. Product Integrity Portfolio Strategic Plan 2007-2010. (Horticulture Australia Ltd., unpublished). Bennett RR. 2014. Food safety and related incidents involving horticulture. (Horticulture Australia Ltd/PMA AustraliaNew Zealand Ltd, unpublished). Centers for Disease Control and Prevention. 2013. Attribution of Foodborne Illness in the USA 1998-2008. Emerging Infectious Diseases 19(3). ORAL SESSION 1 Department of Agriculture Fisheries and Forestry. 2004. Guidelines for On-Farm Food Safety for Fresh Produce. 2nd Edition. Food Standards Australia New Zealand. 2014. Abandonment – Proposal 1015. Primary Production and Processing Requirements for Horticulture. Hall G, Kirk MD, Becker N, Gregory JE, Unicomb L, Millard G. 2012. Estimating foodborne gastroenteritis, Australia. Emerging Infectious Diseases 11(8):1257–1264. Howe T. 2011. Review of Food Safety Systems in Australian Horticulture, FSANZ Proposal 1015 - Primary Production and Processing Requirements for Horticulture, Supporting Document 3. OzFoodNet. 2012. Monitoring the incidence and causes of diseases potentially transmitted by food in Australia: Annual report of the OzFoodNet network, 2010. Communicable Diseases Intelligence 36(3): E213-E241. Roy Morgan Research. 2013. Food safety standards in supermarkets important to more shoppers than location, price or product range. (Media release). Spencer, S., and Kneebone, M. 2012. FOODmap: An analysis of the Australian food supply chain:51. World Health Organisation. 2013. Advancing food safety initiatives: strategic plan for food safety including foodborne zoonoses 2013-2022:7. 7th International Table Grape Symposium 23 Session 2. Soil management and mineral nutrition Soilless table grape cultivation - a review Rosario Di Lorenzo*, P. Scafidi and C. Gambino Dipartimento di Scienze Agrarie e Forestali - University of Palermo - Viale delle Scienze 11, Palermo, Italy * Corresponding author: Tel: +39 328 986 6197, Email: [email protected] Background and Aims ORAL SESSION 2 The competition between producing countries, the changes in consumer needs, the new systems of commercialising and globalisation, impose to table grape industry the development of innovations in production processes and varieties. For these reasons the Agrarian and Forestry Science Department of Palermo University since late nineties (Di Lorenzo et al., 2001; Barbagallo et al., 2005;Di Lorenzo et al., 2009; Gambino et al., 2008; Di Lorenzo et al., 2012) started a study on table grape soilless cultivation. First experiences of table grape soilless cultivation were done already in the 19th century (Foex 1891; Ottavi 1893). “The cultivation of vines in pots, as well as provide pleasure and satisfaction, may be able to give a gain because it often gives amazing results for quantity, quality and beauty of the product...” (Longo, 1926). The goal of present work is the description of growing and managing techniques for soilless table grape cultivation, and in the meantime to show the economic potential of this system. Results and Discussion The soilless table grape cultivation gives the following advantages: 1. Quick varietal renovation In the first year own-roots vines are formed and grown, while in the second year the vines are fully productive. At the end of the first winter, two-bud cuts are put in alveolar pots (0.4L) for rooting. When cuttings are rooted and the shoot is about 20cm long, the vines are transplanted into 10L pots where they receive fertigation through a drip irrigation system with auto-compensating pressure emitters (4L.h-1). The substrate choice is very important, the qualitative and productive results, but also the costs could be very different. The number and the time of fertigation are dependent from substrate characteristics, variety, environmental conditions and phenological stage. The nutrient solution contains (mg/l) 78 N, 22 P, 63 K, 106 Ca, and 22 Mg as macronutrients while EC and pH are adjusted respectively to 1.6 – 2.2mS.cm-1 (at 25 C°) and to 5.5-6.0. The training phase can be carried out inside or outside the greenhouse. At the end of first vegetative season the plant should have one cane, 1.70m long, well lignified, with a diameter of 1-1.5cm. The first productive cycle begins, inside the greenhouse, with winter pruning, leaving the cane about 1.30m long: 0.8m will be vertical portion and 0.50m (4-6 buds) will be rolled on horizontal wire. The vine density for productive cycle can be various (form 1 to 2 vines per square metre) depending of greenhouse features. 2. Enlargement of harvest period In soilless cultivation it is possible to harvest the grapes 15 days before traditional systems under the plastic or in the greenhouse. 3. Out-of-season production With a soilless cultivation it is possible to schedule the vegetative cycle like in the tropical areas. It is possible to harvest early varieties in the late period and late varieties in the early period. 4. Passing of issues like soil tiredness, soil and roots diseases 5. Easy vineyard management 6. Increased productivity 24 7th International Table Grape Symposium The soilless table grape cultivation allows high yield per hectare (35-40 tons per hectare) with appropriate commercial standards. In the Mediterranean area, the yield per hectare can be improved carrying out multiple cycles in the same vegetative season. Research carried out in 2011 in a multi-tunnel greenhouse located in Favara (Agrigento – Sicily - 37 ° 19 ‘N, - 13 ° 39’ E), on Black Magic and Victoria cv. showed that is possible to obtain, with a double cycle, a production of 55-70 tons per hectare. ORAL SESSION 2 In that trial, after the ‘conventional’ production cycle (winter-spring) a ‘late’ cycle (summer-autumn) was carried out comparing vines that have been harvested already in the ‘conventional’ cycle (2° production vines) and cold-stored vines (4°C). Bud-break was on 8 July and the harvest on 15 October for a total of 97 days. The yield per plant was 2.9, 1.4 and 1.9 kg respectively in ‘conventional’ cycle vines, 2° production vines and cold-stored vines, with yield per hectare, considering a plant density of 15.600 plants per hectare, respectively, of 45 tons in ‘conventional’ cycle, 22 tons in 2° production vines and 30 tons in cold-stored vines. In the ‘conventional’ cycle, the bunch weight was 727g, while in the ‘late’ cycle the bunch weight was 422g in cold-stored vines and 562g in the 2° production vines. The quality of grape in the ‘late’ cycle, although it was lower than in ‘conventional’ cycle, was acceptable and appropriate to commercial standards (Cefola et al., 2011). In these trials has been demonstrated that it is possible to carry out, on the same vine, 4 production cycles before to change it. Acknowledgements The authors acknowledge the Sicilian Region Government for the financial support, Dr. Biagio Di Mauro for the technical assistance, and the farms (Agrimed, Fortunato Salerno, Fiorilla, Vita, Minio, Rondinò di Miglione Angré and Sorace) for their collaboration. References Barbagallo MG, Gambino C, Dimauro B, Di Lorenzo R. 2005. Ulteriori considerazioni sulla coltivazione in fuori suolo dell’uva da tavola. Rivista Di Frutticoltura E Di Ortofloricoltura. vol. 1, pp. 32-36 ISSN: 0392-954X. Cefola M, Pace B, Buttaro D, Santamaria P, Serio F. 2011. Postharvest evaluation of soilless-grown table grape during storage in modified atmosphere. Journal of the Science of Food and Agriculture, DOI: 10.1002/jsfa.4432. Di Lorenzo R, Dimauro B, Guarasci F, Rinoldo C, Gambino C. 2012. Più cicli produttivi in un anno nella viticoltura da tavola in fuori suolo. Proceedings of the 35th World Congress of OIV Vine and Wine, 18-22 June 2012, Izmir, Turkey ISBN 979-10-91799-00-3. Di Lorenzo R, Gambino C, Di Mauro B. 2009. La coltivazione dell’uva da tavola in fuori suolo: stato attuale e prospettive. Le Bulletin de L’OIV. Vol. 82, No.935-936-937, pp. 33-44. ISSN 0029-7127. Lavoro preparato per il XXXI World Congress of Vine and Wine, Verona, Italy, 15-20 June, 2008. Di Lorenzo R., Barbagallo MG, Mafrica R, Palermo G, Dimauro B. 2001. “Bio-Agronomic and phisiological aspects of the training of “soilless” table grapes in Sicily”. Atti XII Gesco. Foex G. 1891. “Cours complet de viticulture”. Aux Bureaux Du Progres Agricole Et Viticole. Montpellier Et Villefranche (Rhone) - Bibliotheque Du Progres Agricole Et Viticole: 898-906. Gambino C and Di Lorenzo R. 2008. Comportamento vegeto-produttivo ed ecofisiologico di viti allevate fuori suolo in coltura protetta. Rivista Di Frutticoltura E Di Ortofloricoltura. vol. 1, pp. 22-26 ISSN: 0392-954X. Longo A. 1926. “La coltivazione delle viti in vaso”. Velletri, Luglio. Edizione L’Italia Agricola. Estratto Da L’italia Vinicola Ed Agraria: 65-66; 68-70; 86-87; 103-105. Ottavi O. 1893. Viticoltura Teorico-Pratica. Prenger JJ and Ling PP. 2000. Greenhouse condensation control. Fact Sheet (Series) AEX-804. Ohio State University Extension, Columbus, OH: 1-4. Ruggiero C, Dilorenzo R, Angelino G, Scaglione G, Gambino C, Divaio C. 2012. Root hydraulic conductivity in three self-rooted and grafted table grape cultivars. Journal International des Sciences de la Vigne et du Vin. 01/12. Vidaud J. 1991. “Coltures sous abris en hors-sol”. Special Essais No. 284-239. Ctifl – n.17. 7th International Table Grape Symposium 25 Soil management using no tillage and cover crops in a table grape vineyard in southeastern Italy (Puglia region) G Ferrara1, A Mazzeo1, C Lasorella2, P Montemurro2,*, A Mastropirro3 and M Fracchiolla2 Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti - University of Bari ‘Aldo Moro’, via Amendola 165/A - 70126 Bari (Italy) 2 Dipartimento di Scienze Agro Ambientali e Territoriali - University of Bari ‘Aldo Moro’, via Amendola 165/A - 70126 Bari (Italy) 3 Agriproject Group - Rutigliano (Italy) * Corresponding author: Email: [email protected] 1 Background and Aims ORAL SESSION 2 Southern Italy, in particular Puglia and Sicilia regions, is the main area where table grapes are cultivated, with more than 90% of Italian production. Changing from conventional table grape vineyard soil management, which includes soil tillage and chemical control of weeds, to cover crops mulching has agronomic, economical and environmental advantages, but may create competition between the cover crops and the vine. Over time, different sustainable soil managements systems with different types of mulching techniques (organic, inorganic, artificial mulches) have been proposed for wine grapes, especially in climates with higher amounts of rain, but scarce information is available for such management systems for a table grape vineyard in Mediterranean climates. The objective of the study was to verify the effects of various types of no tillage techniques, including the use of cover crops, in a table grape vineyard under Mediterranean conditions. Experimental Procedure The trial was carried out in the years 2010 and 2011 in a commercial and irrigated 7-year old table grape vineyard located in the countryside of Acquaviva delle Fonti (Ba). The cultivar tested in the trial was Italia, grafted on 1103P and cultivated with an overhead trellising system slightly modified; vines were spaced 2.3m on the rows and 2.8m between the rows. The treatments were: • • • • T1: no tillage, with Trifolium subterraneum L. as cover crop. T2: no tillage with Festuca arundinacea Schreb. as cover crop. T3: no tillage with naturally occurring flora. T4: traditional soil tillage as control. A randomised block design with 4 repetitions was adopted, with a tested area of 5 plants. In the first three treatments, cover crops or natural flora were mowed whenever vegetation reached a height of 20cm. At harvest, yield per vine, berry skin colour and some chemical characteristics of the berries were determined. Results and Discussion In 2010 mean marketable yield per vine ranged from 22.0kg in T4 to 23.9kg in T3; number of bunches/vine ranged from 27.6, in the traditionally tilled control, up to 29.2 in T1 and T2. There were no statistically significant differences among the treatments for all data, including morphological characteristics of berries, titratable acidity, °Brix, pH and ratio °Brix/acidity. Colourimetric analyses (with Minolta® CR-400 colourimeter) gave values statistically different for lightness (parameter L), with a minimum value of 41.0 for T2 to a maximum of 41.6 for the treatment sown with clover. With regards to the chroma (parameter C), a significantly lower value (equal to 9.4) was measured for the tilled control compared to T3, whereas for the angle of colour or hue (parameter h°) there were no significant differences among all treatments. In 2011 the measurements of the marketable production per vine and the number of bunches/vine did not show significant differences. In particular, for the yield the mean values ranged from a minimum of 23.0kg for T3 to a maximum of 25.4kg for T1, whereas the number of bunches ranged from 28.4 (T4) up to 31.0 (T3). With regard to the morphological characteristics of berries any notable difference was found. Mean °Brix values were significantly higher for the tilled control, whereas similar values were measured in all the other treatments. Similarly, titratable acidity was significantly higher in T3 treatment. With regards of the colour of the skin, higher L value was measured in T2 with respect to T1; however, both these treatments were no statistically different from T3. C value was significantly higher in T3 compared to T1 but similar T4 and T2; h° value was not significantly different among the treatments. 26 7th International Table Grape Symposium With regard to the yield and the number of bunches per vine, the weight of the berries, as well as for most of chemical and qualitative parameters, there were no significant differences among all the treatments. Colourimetric data evaluated in treatment sown with fescue, appeared able to provide berries, in both years, with a level of lightness (L) and chroma (C) of the skin higher than the other types of soil management systems evaluated. These results confirm those detected in a previous trial on the quality of the berry, in particular skin colour and berry texture (Mazzeo et al., 2013). We can conclude that in Puglia Region the use of no tillage and cover crops can be considered as a possible alternative to traditional soil management. Paying attention to avoid high competition (mainly nutrients, water and temperature stresses) between cover crop or natural flora and vine, it is possible to eliminate negative effects and even improve the sustainability of table grape production. In particular, soil management with no tillage and cover crop can: • provide fuel savings, due to the limited number of mechanical treatments; increase the soil fertility, as already found in previous experiments conducted in other fruit species, when using legume species, such as T. subterraneum; match the principles of ‘Environmental Conditionality’, included in the most recent environmental measures of the European Community Agricultural Policy. ORAL SESSION 2 • • The presence of the cover crops in the vineyard can also be seen as an adequate agronomic strategy to control vine vegetative growth and yield (Pinamonti et al., 1996), in particular for vigorous cultivars such as Crimson Seedless thus improving the skin colour and the ripening of the berry. Moreover, consumers of agricultural products demand that the use of chemicals and the negative impact of intensive agricultural practices on the environment must be reduced (Fourie, 2011), and the presence of cover crops may be a useful tool. Acknowledgements The authors wish to thank the Valenzano farm for the use of the vineyard. References Fourie JC. 2011. Soil Management in the Breede River Valley Wine Grape Region, South Africa. 3. Grapevine Performance. South African Journal of Enology and Viticulture 32(1): 60-70. Mazzeo A, Matarrese MS, Montemurro P, Pacifico A, Lasorella C, Ferrara G. 2013. Effetti di diverse tipologie di inerbimento sugli aspetti qualitativi della cultivar Italia in provincia di Bari. IV Convegno Nazionale di Viticoltura. Asti, 10-12 Luglio 2012. Quaderni di Scienze Viticole ed Enologiche 32 (2011-2012): 305-309. ISSN: 1970-6545. Pinamonti F, Stefanini M, Dalpiaz A. 1996. Soil management effects on nutritional status and grapevine performance. American Journal of Enology and Viticulture 51: 76-82. 7th International Table Grape Symposium 27 First results on soil management of organic Midnight Beauty® table grapes covered with plastic film in Apulia region Gianvito Masi*, L Tarricone, D Di Gennaro, G Gentilesco and AM Amendolagine Consiglio per la Ricerca e la Sperimentazione in Agricoltura - Research Unit for Viticulture and Enology in Southern Italy, Via Casamassima, 148 70010 Turi (BA) Italy * Corresponding author: Email: [email protected] Background and Aims ORAL SESSION 2 In the world there is an increasing consumer demand for residue-free, organically grown seedless table grapes. Organic table grape cultivation is very delicate and in organic viticulture cover crops are considered a highly sustainability choice for the soil management strategies. There are many choices for cover crops in viticulture, ranging from perennial and annual grasses, to legumes considering that each species has strengths and weaknesses, as well as associated seed and management costs. The use of inter-row cover crops (permanent or temporary) in viticulture has many advantages, with the reduction of water runoff and soil erosion, restriction of evaporation from the soil surface, improvement soil water holding and soil organic matter, the reduction of temperature fluctuations in the soil, as well as the regulation of the vine growth and vigour, with influence on grape quality and quantity (de Palma et al., 2007; Fourie, 2010). Sugrathirteen® (Midnight beauty® brand) is a new early-season black seedless table grape variety obtained by David W Cain in Wasco, (California) and developed and produced under license throughout the world by Sun World Int., (Coachella, California, USA). It’s characterised by high productivity and has firm, low acid, early ripening (ripens along with Superior Seedless) naturally large, elongated black berries, which does not require exogenous applications of gibberellic acid to obtain commercially acceptable berry size (USPP No. 10.434;Gentilesco et al., 2011). In this research three soil management techniques were compared to test their effects on vine growth, vine water status, production and juice composition of organic Sugrathirteen® table grape vines. Experimental Procedure and Results Research was carried out in the year 2012 in the Apulia region in an organic table grape vineyard on Vitis vinifera cv Sugrathirteen (Midnight Beauty® brand), grafted onto Vitis berlandieri x Vitis rupestris 140 Ruggeri rootstock, with a spacing of 3.5 x 2.0 m apart (1.428 vines ha-1), 4 years old located in ‘Gioia del Colle’ area, 344m above sea level, (latitude 40°47°48° N and longitude 16°55°24° E). Vines were cane pruned (six twelve-nodes cane were retained, 72 buds per vine ) and trained to Y trellis system, drip-irrigated and covered on the top of each row with plastic film from budbreak to harvest, to protect canopy and clusters from the negative effect of wind, rain and hail. Annual average rainfall in the region is moderate (500mm. year-1) with high summer evaporation and low relative humidity. In this research three soil management strategies were compared: (MC) mechanical cultivation along the rows and inter-rows, (RV) mechanical cultivation along the rows while inter-rows space were occupied by permanent resident vegetation (cheap and generally easy to manage) and (TR) mechanical cultivation along the rows while inter-rows space were sown with Trifolium subterraneum L. ssp. brachycalicinum cv Antas. The clover cover crop was sown during the end of November 2010 and the seedbed preparation was done with a disc harrow approximately two weeks before the seeding date. After mechanical sowing, the clover seeds were covered using a disc harrow. In conclusion in two cover crop types, the vineyard soil management consists of two zones: the rows, a 70cm wide area underneath the vines, which are managed primarily to control weeds by mechanical cultivation and the middles, interspersed between the rows, which are vegetated by clover cover crops or resident vegetation and are mown three fold per year in spring and early summer. Cultivation was carried out every 4 to 5 weeks during the growing season with a cultivator equipped with trunk sensor to avoid vine damage. Irrigation was provided trough drip system with a single irrigation line per row and pressure-compensated emitters, with a discharge rate of 10L.h-1 per vine respectively. Drip irrigation and fertigation were applied uniformly across all treatments and fertiliser was not applied to the grass cover. Soil water content was evaluated from soil moisture sensors (10 HS Decagon Device Inc.) installed in-row and adjacent middles to a depth of 60 and 30cm in all plots. 28 7th International Table Grape Symposium Soil of the experimental vineyard is characterised by a medium chemical fertility and soil texture was clay-loam. On 15 vines per treatment, shoots and clusters number per vine, were assessed, and fruitfulness was calculated. Cluster number of vines was standardised one week after berry set in order to retain an average of 30 bunches per vine in all treatments with manual cluster thinning. To quantify vine water status, midday stem water potentials (Ψmds) were measured on 10 leaves of similar maturity per treatment with a pressure chamber (3005F01, Soilmoisture Equipment Corp., Santa Barbara CA, USA). Leaf stomatal conductance was determined on cloudless days during ‘midday’ period using a portable porometer (Model SC-1, Decagon Devicess, Pullman, WA). Moreover, in a typical day of July, parameters of physiological leaf gas exchange were measured, between 12:00 and 14:00 solar time, on well-exposed main leaves of the second node above the distal cluster on a middle vigorous shoot (4 leaves per replicate) at ~1500μmol.m-2 .s-1 of photosynthetic photon flux (ADC Mod. LCproSD, ADC BioScientific Ltd., Hoddesdon, UK). ORAL SESSION 2 At the commercial harvest, on random samples of 45 clusters per treatment, bunch and berry mass, cluster length, berry diameters and yield per vine were determined. On a juice samples the total soluble solids, titratable acidity and pH were also determined. Besides, 50 berries per treatment were randomly sampled and their skin firmness, berry removal force and firmness were determined using a digital penetrometer (Digital Fruit firmness tester, TR Turoni S.r.l., Forlì, Italy). On a sample of 100 berries per treatment the berry skin colour parameters (brightness L*, a* measure of range colour from green (-) to red (+) and b* measure of range colour from blue (-) to yellow (+)) by use of colourimeter (Minolta Croma Meter CR 400) were determined. After the harvest, six vines per treatment were completely defoliated and total leaf area per vine determined with a leaf area meter (area-meter Li-3100, LI-COR, USA) and the leaf area/crop weight ratio was calculated. During winter period vegetative growth was quantified by measuring cane mass at pruning and the fruit to pruning weight ratio was calculated. Data were statistically analysed using procedure of Systat 11 package (SYSTAT Software Inc., Richmond, California, USA). The different soil management strategies have influenced bud fruitfulness with the highest clusters number per vine in TR treatment. Compared to TR treatment, a reduction of cluster number per vine of 21% and 8% was observed for MC and RV treatments respectively (Table 1). Midday stem water potential showed slight differences between treatments during the shoots growth and at véraison. At véraison, midday stem water potential in TR and RV vines reached the minimum value of -1.02 and -0.98 MPa (moderate water stress) and were significantly lower than that of MC vines. Same tendency was observed for stomatal conductance, given that the competition of cover crops affected the stomata aperture as indicated by lowest values on TR and RV vines during shoots growth (Table 2). Table 1. Vegetative and yield characteristics of Sugrathirteen® vines before cluster thinning. Buds per vine (n) Shoots per vine (n) MC 72 a TR 72 a RV 72 a Treatment Clusters per vine (n) Clusters per vine/Buds per vine Clusters per vine/Shoots per vine 52.67 a 59 b 0.82 b 1.12 a 57.70 a 74.33 a 1.03 a 1.29 a 56.73 a 68.67 ab 0.95 ab 1.21 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. Table 2. Midday stem water potential and stomatal conductance of Sugrathirteen® vines. Parameter Midday stem water potential (Ψmds, MPa) Stage Shoot growth Pea-size Véraison Harvest MC -0.87 b -0.89 a -0.72 b TR -1.04 a -0.92 a -1.02 a RV -1.01 a -0.87 a -0.98 a Stomatal conductance (mmol.m-2.s-1) Shoot growth Pea-size Véraison Harvest -0.88 a 393.10 a 392.70 a 301.33 a 347.09 a -0.96 a 223.20 b 352.40 a 316.04 a 299.38 a -0.72 a 275.50 b 388.90 a 307.64 a 352.62 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. 7th International Table Grape Symposium 29 The gas exchange of leaves exposed to about 1500μmol.m-2 .s-1 of direct photosynthetically active radiation, showed considerably higher rates of stomatal conductance and net photosynthesis in all treatments. MC vines have shown the lowest leaf transpiration and leaf temperature (Table 3). Table 3. Leaf gas exchange of Sugrathirteen® vines. Parameter/Treatment Leaf temperature (°C) Stomatal conductance (mol.m-2.s-1) Net photosynthesis (µmol.m-2.s-1) Transpiration (mol.m-2.s-1) WUE (µmol:mmol) MC 33.60 b 0.295 a 13.08 a 4.72 b 2.77 a TR 35.42 a 0.352 a 12.77 a 6.35 a 2.20 b RV 35.22 a 0.342 a 13.10 a 5.88 ab 1.99 b ORAL SESSION 2 In column, means followed by different letters were significantly different at P=0.05 using SNK test. Soil moisture declined most rapidly in the middles of MC plots during periods without rainfall and remain stable for more time in TR middles. At harvest no significant difference among treatments were noted for bunch weight and berry physical parameters (Table 4) while cover crops had a significant impact on berry weight. Berry weight shown the lowest value in mechanical cultivation vines compared with the two types of cover crops. In all plots with ground cover, berries number per cluster was lower than tilled treatment probably due to the high competition of cover crops in the blooming period of grapevine. In the tilled vines the absence of weeds competition have allowed a higher fruit set, and consequently highest berries number per cluster, with a reduction of the berry weight, as expected. At the beginning of August, ‘Sugrathirteen® grapes of TR and RV treatments reached 16.70÷16.90° Brix; the lowest total soluble solids was reached in MC vines with a decrement of 9% (Table 5). Titratable acidity was quite low and ranged between 5.3g.L-1 (on MC and RV vines) to 5.7 (on TR vines). Table 4. Quantitative fruit parameters of organic Sugrathirteen® table grape at harvest. Treatment Bunch weight (g) Rachis Berry weight per (g) cluster (n) Berry weight (g) Polar Equatorial Cluster Skin Berry Firmness diameter diameter compact- firmness removal (g) (mm) (mm) ness index (g) force (berry/cm (g) rachis) MC 563.51 a 13 a 131 a 4.30 b 24.39 a 19.61 a 5.69 a 140 a 270 a 1320 a TR 554.86 a 11 ab 116 ab 4.80 a 23.99 a 19.41 a 5.27 a 120 a 260 a 1360 a RV 518.18 a 10 b 108 b 4.70 a 22.79 b 18.77 b 5.14 130 a 270 a 1420 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. Table 5.Berry parameters and skin colour coordinates of organic Sugrathirteen® table grape at harvest. Treatment Total soluble solids (°Brix) Titratable acidity (g.L-1) pH L* (brightness) a* (greenness) b* (yellowness) MC 15.20 b 5.32 b 3.29 b 31.41 a 2.49 b -7.14a TR 16.70 a 5.74 a 3.26 c 29.69 b 2.89 a -7.49 b RV 16.90 a 5.32 b 3.39 a 31.65 a 2.86 a -7.88 c In column, means followed by different letters were significantly different at P=0.05 using SNK test. In our research berry sugar content was not correlated to yield per vine, in fact the yield was similar and no significantly different among treatments (Table 6) considering the same clusters number retained per vine after cluster thinning. Monthly field measurements of SPAD (greenness index of leaves) throughout the 2012 seasons showed significant differences among treatments with the highest values on leaves of MC vines (data not shown). Skin colour parameters didn’t shown significant differences between treatments (Table 5), on the other hand Sugrathirteen® is a grape variety with no problem of skin berry colour, also in relation to specific anthocyanins composition (Tarricone et al., 2011). 30 7th International Table Grape Symposium Different soil management induced significant differences in total leaf area per vine. Leaf area of TR vines (clover cover crop) was quantitatively higher than that of the other soil treatments (Table 6) and maximum berry weight was obtained in TR treatment which showed a highest leaf area (m2) per fresh yield (kg) ratio. Leaf area crop weight ratio reached values about of 1m2.kg-1 in TR and RV vines, but it was reduced of 21% in MC vines, not differed from optimal values comprised between 0.8 to 1.2m2.kg-1 of fruit (Kliewer and Dokoozlian, 2005). Different soil management did not reduce significantly the vegetative growth (Table 7) as shown by the pruning weight, cane weight and considering the Ravaz index (crop yield/pruning weight). Table 6. Main vegetative parameters of Sugrathirteen® vines. Treatment Total leaf area per vine (m2 vine-1) Leaf area/yield (m2 kg-1) MC 16.90 a 13.70 b 0.81 b TR 16.64 a 17.13 a 1.03 a RV 15.54 a 14.93 b 0.96 a ORAL SESSION 2 Yield (kg vine-1) In column, means followed by different letters were significantly different at P=0.05 using SNK test. Table 7. Effect of the soil management on the pruning weight of Sugrathirteen® vines. Treatment Pruning weight (g) Average cane weight (g) Ravaz Index MC 2767 a 61.30 a 6.76 a TR 2989 a 89.53 a 5.87 a RV 2369 a 59.80 a 6.94 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. Discussion and Significance of the Study According to the preliminary results cover crops had positive effects on berry sugar content and berry weight of organic Sugrathirteen® vines. These parameters were higher and statistically different in all plots with grass cover compared to mechanical cultivation. This can be explained by the vegetative cycle and low competiveness of resident weeds in the vineyard also in relation to the shade effect on cover due to grapevine canopies. Finally, the benefit of temporary clover cover crop, which was at beginning of véraison (July) in its summer standstill, and exerts mulching effect and less water competition to the vines, was evaluated. In conclusion a temporary cover crop with clover or resident vegetation had no negative effect on vine growth and productivity of organic seedless table grape, with clear benefits of the cover crops in relation to soil compaction, soil water storage, organic matter and soil microbial biomass. Acknowledgements The work was supported by the Italian Ministry of Agriculture and Forestry Policy (D.M. MIP.A.A.F 26763/7818/2011 del 15/12/2011, Bando Progetti di ricerca per PMI agricole proposti da piccole e medie imprese condotte da giovani imprenditori agricoli) Project “METODI DI GESTIONE ECOSOSTENIBILI NELLA PRODUZIONEDI UVE DA TAVOLA APIRENE ”, acronimo ECO.APIREN; publication No. 1. References de Palma L, Novello V, Tarricone L, Frabboni L, Lopriore G, Soleti F. 2007. Qualità del prodotto e protezione agronomica dell’ambiente edafico in un sistema vitivinicolo dell’Italia meridionale. Quaderni di Scienze Viticole ed Enologiche University of Torino 29: 83-111. Fourie JC. 2010. Soil management in the Breede River Valley wine grape region, South Africa. 1. Grapevine performance. South African Journal of Enology and Viticulture 32: 60-70. Fourie JC. 2010. Soil management in the Breede River Valley wine grape region, South Africa. 3. Cover crop performance and weed control. South African Journal of Enology and Viticulture 31: 14-21, 165-168. Gentilesco G, Amendolagine AM, Giannandrea MA, Notarangelo L, Roccotelli S, Suriano S, Savino M, Romanazzi V, 7th International Table Grape Symposium 31 Tarricone L. 2011. Effect of crop load and time of girdling on Sugrathirtheen® table grape: first results. Le Progrés Agricole et Viticole, Proceedings 17th International Symposium GiESCO, Asti-alba (CN). Italy 29 august- 2 September 2011: 419-422. ISSN: 0369-8173. Kliewer WM and Dookzlian NK. 2005. Leaf area/crop weight ratios of grapevines: influence of fruit composition and wine quality. American Journal of Enology and Viticulture 56: 170-181. United States Plant Patent No. 10.434: June 9, 1998. ORAL SESSION 2 32 7th International Table Grape Symposium Advancing ripening of Scarlet Royal grown in the desert region in California William L Peacock1, Joseph L Smilanick2 and Carmen Gispert3,* University of California, Cooperative Extension. Visalia, CA 93292. Viticulturist Emeritus USDA-ARS. San Joaquin Valley Agricultural Sciences Center 9611 S. Riverbend Ave., Parlier, CA 93648. Retired Plant Pathologist 3 University of California, Cooperative Extension, 81-077 Indio Blvd. Suite H, Indio, CA 92201 * Corresponding author: Tel: 760 342 2466. Email: [email protected] 1 2 Background and Aims ORAL SESSION 2 Colour development is a limiting factor to grow Scarlet Royal in the desert region and is common practice to use colour enhancement materials such as Ethephon and abscisic acid (ABA) to colour the bunches. In red grapes, anthocyanins are responsible for the colour red which start accumulating at véraison (Somers 1976). The content and composition of anthocyanins is influenced by numerous factors and can be manipulated by viticultural practices such as canopy management, yield regulation, irrigation and timing of harvest (Downey, et al., 2006). In previous work we observed that the application of foliar potassium accelerated berry maturity as defined as soluble solids content, but did not influence the composition of sugars as determined by fructose/glucose ratio, or influence titrable acid content, so berry flavour would not change by potassium applications (Smilanick et al., 2013). In this study we evaluated the efficacy of foliar potassium, ethephon, abscisic acid and a maturity girdle in combination with deficit irrigation on fruit colour, vine production and vine growth. Experimental Procedure The experiment was designed as a 3x factorial. Factor A compared two treatments: fully irrigated vines with vines deficit irrigated. Factor B compared two treatments: Albion foliar K (3.785L per 4047m2) applied at 14° Brix along with a control. Factor C evaluated four treatments: ethephon (946mL per 4047m2), abscisic acid (150g per 4047m2), maturity girdle, and untreated control. The plant growth regulators (PGRs) and girdle treatments were all applied in early véraison. Plot size consisted of three blocks with three vines each with a total of 48 plots. Table 1. Experiment design, completely randomised split pilot. Treatment Factor Factor A Irrigation Factor B Foliar K Factor C PGRs 1. Full 1. Control 1. Control 2. Deficit 2. K at 14° brix 2. Ethephon 3. ABA 4. Maturity girdle In this study, deficit irrigation consisted of applying full evapotranspiration (ET) from budbreak until the lag phase and then fifty percent ET through ripening and harvest. Irrigation amounts were based on the San Joaquin Drip Irrigation Scheduler (Peacock et al., 1978), modified for the desert area, and adjusted based on tensiometers. Water meters were used to record amounts applied to both deficit and full ET treatments. During the period from 28 March (three weeks after bud break) to 21 May (early véraison) deficit and full irrigation treatments received about 5.5 acre inches (565.3m3) of water. Deficit irrigation at 50% ET began 21 May, and continued throughout ripening until harvest in July. During the ripening and harvest period the deficit and full irrigation treatments received 5.6 acre inches (575.6m3) and 10.4 acre inches (1069m3) respectively. Results and Discussion Deficit irrigation can impact metabolite accumulation decreasing root and shoot growth (Jones, 1992). In this study the primary purpose of deficit irrigation treatments during fruit ripening was to slow shoot growth and redirect the flux of carbohydrates to the fruit. The amount of stress due to deficit irrigation can have negative impacts on fruit and vine development and it will be important to find the right level of deficit irrigation to maximise fruit maturity while minimising negative impacts on fruit and vine capacity. 7th International Table Grape Symposium 33 In 2013, harvest occurred on 1 July. Fruit was determined harvestable solely based on colour when 90% of the berries on a cluster were 90% coloured. Results showed that harvestable fruit increased from 6% to 12% when deficit irrigation treatments were compared to full irrigation. However, deficit irrigation in combination with foliar potassium increased harvestable fruit from 6% to 24%. The most effective deficit irrigation treatment was foliar potassium plus ethephon, which increased harvestable fruit from 6% to 35%. Under full irrigation, the most efficacious treatment was foliar potassium with either ethephon or maturity girdle. We found that berry characteristics as soluble solids, berry weight, berry width, and berry firmness were not affected by deficit irrigation, foliar K, ethephon, abscisic acid, or maturity girdle treatments and did not have a significant impact on cluster rot, sunburn, or shrivel berries. ORAL SESSION 2 When soluble solids were compared at 5% no significant differences were found, however, there was significance at the 15% level. The maturity girdle and ethephon advanced soluble by about 0.8° Brix, and the combination of a maturity girdle and foliar potassium advanced maturity by almost 1.0° Brix compared to the untreated control. There was a positive interaction between foliar potassium and deficit irrigation. Deficit irrigation during fruit ripening enhanced colour and sugar maturity compared to vines fully irrigated. Under full irrigation, the most efficacious treatment was foliar potassium and ethephon. The greatest increase in fruit colour occurred with the combination of deficit irrigation, foliar potassium and ethephon, which increased packable fruit (based on colour) from 6% to 35%. Although vines were stressed for four weeks during ripening, deficit irrigation had no negative effects on fruit quality (berry weight, firmness, rot, shrivel, or sunburn), however it will be important to consider that colour could be improved with a shorter period of deficit irrigation. Significance of the Study Understanding factors that may affect the firmness, size, and colour of grape berries, and the identification of interactions among these and deficit irrigation, foliar potassium and ethephon, would be useful to understand how they affect fruit ripening. Acknowledgments Funding was provided by the California Table Grape Commission. 392 W. Fallbrook, Suite 101. Fresno, CA 937116150. References Downey MO, Dokoozlian NK, Kristic MP. 2006. Cultural practice and environmental impacts on the flavonoid composition of grapes and wine: A review of recent research. American Journal of Enology and Viticulture 57: 257268. Peacock WL, Christensen LP, Andris HL. 1987. Development of a drip irrigation schedule for average-canopy vineyards in the San Joaquin Valley. American Journal of Enology and Viticulture 38:113-119. Smilanick JL, Gispert C, Peacock WL. 2013. Development of foliar potassium and deficit irrigation strategies that optimise fruit quality. California Table Grape Research Report. Vol.41. Somers TC. 1976. Pigment development during ripening of the grape Vitis 14: 269-277. 34 7th International Table Grape Symposium Session 3. Rootstocks, breeding and cultivar improvement Keynote address Advanced genetic improvement strategies: New vines for new times Mark R Thomas*, Ian B. Dry, Angela Feechan, Pat Corena and Don Mackenzie CSIRO Agriculture Flagship, Wine Innovation West Building, Waite Campus, Urrbrae, SA 5064, Australia *Corresponding author: Tel: +61 8 8303 8600, Email: [email protected] Background and Aims ORAL SESSION 3 Reducing input costs and having a desirable marketable product are both key to ensuring economic sustainability. Grapevines are highly susceptible to a wide range of pests and microbial pathogens. Historically, grape growers have relied heavily on the use of pesticides and fungicides, in combination with various management techniques, to minimise the impact of these pathogens. There is, however, increasing financial, regulatory and market pressure on grape growers to minimise the application of agrochemicals in the vineyard. In the face of these increasing pressures, the development of new grapevine cultivars with improved genetic resistance to pathogens is a high priority. In other crops, such as cereals, similar diseases have been controlled by breeding to incorporate resistance genes. However, previous attempts to introgress resistance by conventional grapevine breeding strategies has been hampered by the slow generation times and the costs required to propagate and screen sufficiently large numbers of progeny to identify resistant cultivars. The most economically important diseases of grapevine cultivation worldwide are caused by powdery mildew and downy mildew. These pathogens, endemic to North America, were introduced into Europe in the 1840s and have subsequently spread to all major grape producing regions of the world. The wild North American grapevine species Muscadinia rotundifolia was recognised as early as 1889 to be resistant to both powdery and downy mildew. This paper will give an overview of progress we have made both in the identification of the genes responsible for powdery and downy mildew resistance in M. rotundifolia and the introduction of mildew resistance genes into existing grape cultivars either by genetic transformation or marker-assisted selection. Future deployment of these new disease-resistant cultivars will also be discussed and how similar approaches can be used to produce improved table grape varieties. Experimental Procedure and Results We have developed a number of advanced genetic tools to reduce the time taken to produce new grapevine varieties. These are: • Microvine plants for rapid forward and reverse genetic studies in grapevine (Chaib et al., 2010). • Genetic modification (GM) methods to introduce genes in grapevine (Franks et al., 1998; Iocco et al., 2001; Bouquet et al., 2008). • Linking DNA markers to grapevine traits (Chaib et al., 2010; Fernandez et al., 2013) for marker-assisted selection (MAS). The use of rapid cycling microvine plants has allowed the rapid testing and linking of DNA markers to traits of economic importance to identify candidate genes responsible for the trait. GM studies and gene expression and DNA sequencing studies have allowed the identification of the gene responsible for a trait to be confirmed and to produce a GM plant containing the trait of interest such as a mildew resistance gene. This information when known can also be used in a MAS approach to develop a DNA marker panel to screen thousands of grapevine seedlings to select both disease resistant traits and specific fruit traits without the need to grow the plant in the field for fruiting and evaluation. Only a small percentage of seedlings having the correct DNA profile and therefore gene allele combinations (e.g. 15% or less depending on the traits being selected for) are selected for further field evaluation. This represents a considerable saving in resources and time. 7th International Table Grape Symposium 35 We have used the above approaches to produce both GM vines resistant to mildew and non-GM vines resistant to mildews by MAS. Discussion and Significance of the Study We have developed new vines for both research and industry adoption. For research we have developed a number of unique microvine genotypes that provide a model system suitable for rapid forward and reverse genetic studies in small controlled environments. It is based on the Vvgai1 mutant allele that confers a dwarf stature, short generation cycle and continuous flowering. The microvine provides a unique system for rapid genetic studies of grapevine by changing the perennial long life cycle of the plant to one with features and advantages similar to an annual plant. We have used this model system for studying gene function and linking genes and DNA markers to traits. For industry we have investigated both a GM approach and the use of DNA markers linked to traits for markerassisted selection of new grapevine varieties to produce the first generation of low input varieties based on genetic selection that are superior to the old conventional varieties in terms of reduced production costs, performance and market protection. ORAL SESSION 3 Combining disease resistance with improved grape quality can be achieved over a relatively short time frame using advanced genetic improvement strategies compared to traditional breeding methods. Reducing the time from research to adoption was an important part of the research as well as industry involvement in the screening and evaluation of the new vines. GM or non-GM approaches to grapevine improvement have different advantages and disadvantages. At the present time it appears that GM vines will remain an important component of research. For new improved varieties for industry adoption the non-GM MAS approach would appear to be the most attractive. Acknowledgements This work was funded in part by CSIRO Plant Industry, Grape and Wine Research Development Corporation and the Institut National de Recherche Agronomique, France. We thank Vladimir Jiranek, Tommaso Liccioli and Frank Schmid from the University of Adelaide and Peter Rogers from DPI VIC for winemaking. Greatly appreciated was the advice and guidance from members of the Industry Winemakers Group associated with the project. References Bouquet A, Torregrossa L, Iocco P, Thomas MR. 2008. Grapes. In: C Kole, TC Hall, eds, Compendium of Transgenic Crop Plants: Transgenic Temperate Fruits and Nuts, Vol 4. Blackwell Publishing, Oxford, pp 189-232. Chaib J, Torregrosa L, Mackenzie D, Corena P, Bouquet A, Thomas MR. 2010 The grape microvine - a model system for rapid forward and reverse genetics of grapevines. Plant Journal 62: 1083-1092. Fernandez L, Chaib J, Martinez-Zapater JM, Thomas MR, Torregrosa L. 2013. Mis-expression of a PISTILLATA-like MADS box gene prevents fruit development in grapevine. Plant Journal 73: 918-928. Franks T, He DG, Thomas M (1998) Regeneration of transgenic Vitis vinifera L. Sultana plants: genotypic and phenotypic analysis. Molecular Breeding 4: 321-333. Iocco P, Franks T, Thomas MR. 2001. Genetic transformation of major wine grape cultivars of Vitis vinifera L. Transgenic Research 10: 105-112. 36 7th International Table Grape Symposium New table grape varieties obtained in the breeding program by ITUM-IMIDA in Spain Juan Carreño1,*, M Tornel1 and I Carreño2 IMIDA, Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario. Dept. Viticulture and Enology, Table Grape. C/ Mayor s/n, 30150 La Alberca, Murcia, Spain 2 ITUM (Research and Technology Table Grape), Lomas de Marín s/n 30540 Blanca, Spain * Corresponding author: Tel: 34 616309563, Email: [email protected] 1 Background and Aims ORAL SESSION 3 IMIDA started the table grape breeding program in 1991. ITUM is a private company which includes most table grape growers in the region of Murcia and was created in order to develop new table grape varieties. ITUM and IMIDA started together a new table grape breeding program in 2003. The main goal of our breeding program is to develop new table grape varieties with good quality for the consumer and economically profitable for the farmer and the marketing. Our aim is to obtain very productive varieties with no production or marketing problems. In recent years we have started a new line of crosses in order to obtain resistant varieties for powdery and downy mildew. We have promising new hybrids that will soon be registered as high quality varieties which are resistant to these fungi. Experimental Procedure and Results In our program we use the classical crossing method with embryo rescue when we use two seedless varieties as parents. We started the program by hybridising the best Spanish seeded varieties with the best seedless varieties worldwide. To date ITUM has released twelve varieties and expects to release six new varieties in the near future. Varieties in commercial planting or production are described below: Itumone • Early-middle season (harvest: two weeks after Sugraone), white seedless • Neutral-acidic flavour (like Crimson) • Berries are crunchy, 18-23mm diameter • Productivity: I.F. (bunches / shoot) 1-1.5, 450-550g bunch weight • Not require manual cluster thinning • Very little or no gibberellic acid for thinning. Very little gibberellic acid for sizing Itumfour • Late season (mid-August to mid December in Spain), white seedless • Neutral flavour • Berries are crunchy, 18-22mm diameter • Productivity: I.F.: 1.2-1.5, 500-550g bunch weight • Not require manual cluster thinning • Very little gibberellic acid for thinning. Very little gibberellic acid for sizing • Long duration of the clusters on the plant Itumfive • Late season (mid-August to end of December in Spain), white seedless • Neutral flavour • Berries are very crunchy, 18-23mm diameter • Productivity: I.F.: 0.5-0.8, 700-850g bunch weight • Not require manual cluster thinning • Very little or no gibberellic acid for thinning. Very little or no gibberellic acid for sizing • Long duration of the clusters on the plant • Very good cold storage Itumsix • • • • • • • • Late season (mid-August to end of December in Spain), white seedless Neutral flavour Berries are very crunchy, 18-22mm diameter Productivity: I.F.: 0.8-1.1, 650-800g bunch weight Not require manual cluster thinning Gibberellic acid for thinning 1-2ppm. Very little gibberellic acid for sizing Long duration of the clusters on the plant Very good cold storage 7th International Table Grape Symposium 37 Itumeight • Middle-late season (-1 week Crimson), Red seedless • Neutral-acidic flavour • Berries are very crunchy, 18-22mm diameter • Productivity: I.F.: 0.8-1.2, 700-850 g bunch weight • Not require manual cluster thinning • Very little gibberellic acid for thinning. Very little gibberellic acid for sizing • Very productive and colours easily Itumnine • Middle-late season (like Crimson), Red seedless • Neutral-acidic flavour (like Crimson) • Berries are very crunchy, 18-22mm diameter • Productivity: I.F.: 0.8-1, 700-850g bunch weight • Not require manual cluster thinning • Very little gibberellic acid for thinning. Very little gibberellic acid for sizing • Very productive and colours easily ORAL SESSION 3 Itumtwelve • Middle-late season (like Autumn Royal), very nice dark black • Neutral-acidic flavour (like Crimson) • Berries are very crunchy, 18-21mm diameter • Productivity: I.F.: 0.8-1, 450-550g bunch weight • Not require manual cluster thinning • Very little gibberellic acid for thinning. Very little gibberellic acid for sizing • Good resistance to rain and cold storage Varieties for next year: Itumthirteen • Middle season (like Princess), white seedless • Light muscat flavour • Berries are very crunchy, 18-24mm diameter • Productivity: I.F.: 0.8-1, 500-700g bunch weight • Not require manual cluster thinning • Very little gibberellic acid for thinning. Very little gibberellic acid for sizing • Good resistance to rain and cold storage Itumfourteen • Middle-late season, red seedless • Light muscat flavour • Berries are crunchy, 19-25mm diameter • Productivity: I.F.: 0.8-1, 500-700g bunch weight • Not require manual cluster thinning • Very little or no gibberellic acid for thinning. Very little gibberellic acid for sizing • Good resistance to rain and cold storage Varieties for the coming years: 07-313-1: Early season, white colour, light muscat flavour, very crunchy 10-21-12: Early season, white colour, light muscat flavour, crunchy 08-339-50: Early-middle season, red colour, very nice muscat flavour, crunchy 08-339-24: Early-middle season, bright red colour, light muscat flavour, very crunchy 07-415-13: Mid-late season, red colour, light muscat flavour, very crunchy We are also developing several hybrids resistant to powdery mildew and downy mildew. Acknowledgements Research support from the Consejería de Agricultura of the Murcia Region, IMIDA and the ITUM company. 38 7th International Table Grape Symposium Developments in the Australian table grape breeding program Peter Clingeleffer1,2*, Belinda McCarthy2,3, Colin Gordon4, Ian Cameron4, David Oag5, Cameron McConchie6 and Rob Walker1,2. CSIRO Agriculture, PMB 2, Glen Osmond, SA 5065 Formerly CSIRO Plant Industry, Merbein, Victoria 3505 3 Australian Table Grape Association, Mildura, Vic 4 Department of Agriculture and Food Western Australia, Perth, WA 5 Department of Employment, Economic Development and Innovation, Stanthorpe, Qld 6 Northern Territory Department of Resources, Berrimah, NT * Corresponding author: Tel: (08) 8303 8721, Email, [email protected] 1 2 Background and Aims ORAL SESSION 3 The Australian table grape grower is faced with new and evolving challenges surrounding production in a changing and variable climate, increasing consumer and regulatory demands with respect to product integrity and environmental responsibility and a need to maintain international competiveness. Table grape industries throughout the world are adopting new, deliberately bred varieties with a trend towards seedless types. The table grape industry, Horticulture Australia, CSIRO and collaborating research organisations have supported a national approach to table grape breeding and development since 1998 (Clingeleffer 2005, 2010, 2013). Breeding strategies have aimed to develop varieties to address specific market requirements in terms of key consumer based quality traits (seedlessness, berry size, texture and flavour), disease resistance, early and late maturity to extend the harvest season, long storage life to allow access to more distant markets and development of alternate varieties to Thompson Seedless that are not prone to berry collapse. Modern management practices were applied to advanced selections grown in key regions with different climates and seasonality in a nationally coordinated approach with input from collaborating agencies in Queensland, the Northern Territory and Western Australia. These regional tests included application of various management techniques to enhance quality (eg. pruning regimes, bunch thinning and trimming, GA where appropriate) and visual, physical, chemical and sensory evaluation of fruit at harvest and after long-term storage. This paper provides an overview of the program leading to the release of new table grape varieties and to new knowledge incorporated into the studies. Experimental Procedures and Results Conventional hybridisation techniques between selected parents were used to produce new seedling progeny. The progeny were evaluated at different stages of development (i.e. as single vine seedlings, promising selections established in multiplied plots including grafted on rootstocks, advanced selections established in regional sites with different climate and management practices and, for near to release selections, established on semicommercial grower sites to refine management practices and provide sufficient fruit for test marketing. Key components of the program have been the improvement in embryo rescue techniques for crosses between seedless parents, the development of disease resistant screening techniques and application of modern quantitative genetic methods to understand the inheritance of key characteristics (Clingeleffer et al., 1999, 2003, 2009; Sykes et al., 2001). 1. Embryo rescue In order to improve the efficiency of breeding seedless varieties, in-ovulo embryo rescue techniques were used to develop new hybrids from seedless x seedless grape crosses (Clingeleffer et al., 1999). Under in-vitro conditions (i.e. in tissue culture), embryos which would normally abort, continue to develop and can be established as normal plants in the research vineyard. Over the course of the program more than 200 seedless x seedless combinations were tried, including 25% which were unsuccessful and produced no progeny. This may be attributed, at least in some cases, to the fact that seedlessness can be due to pathenocarpy, where berry development occurs without fertilisation and development of an embryo (Clingeleffer et al., 2003). Investigations to improve the efficiency of the embryo rescue technique included effects of genotype; the culture medium, including supplements of various minerals, plant growth regulators and other organic substances; and the effect of ovule age at removal on ovule elongation, embryo recovery, embryo growth and plantlet formation (Liu et al., 2003a, 2008a). As a result, survival rates at all stages of culture improved (i.e. ovule culture, embryo rescue and plant acclimatisation), giving results comparable to overseas programs (Liu et al., 2003a). 7th International Table Grape Symposium 39 2. Disease resistance screening A major aim of the program was to develop disease resistant varieties to reduce usage of agrichemicals in the vineyard (Clingeleffer et al., 1999, Sykes et al., 2001). The main diseases targeted were botrytis bunch rot (Botrytis cinerea), powdery mildew (Uncinula necator) and downy mildew (Plasmopara viticola), which originate from the American continent. A diverse range of disease resistant genotypes were used as parents. In some cases, crosses over a number of generations have produced complex pedigrees in the breeding lines. Parents used have included V. rotundifolia, V. cinerea, V. caribaea, V. longii, V. aestivalis and V. labrusca as well as hybrids with pedigrees incorporating many species. Rapid, leaf based laboratory screening protocols were developed for powdery and downy mildew (Sykes et al., 2001; Liu et al., 2003b; Liu et al., 2008b) and used to assess hybrid populations for resistance (Liu et al., 2008). Among the hybrid populations there were no lines completely resistant to powdery mildew but some that had complete resistance to downy mildew (Liu et al., 2008). Correlations between powdery and downy mildew resistance were weak. For downy mildew resistance appears to be governed a limited number of recessive genes, indicating potential to develop molecular markers to rapidly screen very young seedlings (Liu et al., 2008b). ORAL SESSION 3 The disease screening results show that development of varieties which are tolerant or resistant to both powdery and downy mildew is achievable. Indeed, CSIRO recently released a new, early ripening, disease resistant currant variety with small black berries, M 48-42 (syn. Black Gem) which can be grown without the use of fungicides (Clingeleffer et al., 2011). Black Gem was selected from progeny of a controlled cross between Seyve-Villard 39-639, a complex multispecies, disease resistant hybrid and Beauty Seedless, a black, early ripening table grape variety. There has been limited niche marketing of Black Gem as a table grape in domestic and export markets. 3. Inheritance of key characteristics. Genetic parameters including heritability and genetic correlations of production and fruit quality characteristics were investigated to enable effective selection of parents and to predict outcomes of crosses with greater accuracy (Wei et al., 2003a). Yield and quality characteristics were collected across a diverse range of complex bi-parental progenies comprising of more than 5000 seedlings involving combinations of 40 female and 60 male parents in 1999 and 2000 (Wei et al., 2002; Wei et al., 2003 a,b). Genetic parameters were estimated from data for each season separately and from data pooled over both years using advanced statistical methods (Wei et al., 2003a). Narrowsense heritability estimates (h2) provided a basis for selection of parents based on their estimated breeding values, which indicate how well they will transmit the characteristics they display to progenies. Overall, there were three major findings applicable to table grape varietal development (Wei et al., 2002; Wei et al., 2003 a,b). First, most characteristics were generally under medium to strong genetic control and reasonable genetic gain could be expected from selection based on individual vine performances. This was particularly the case for quality traits where the estimates h2 indicated that selection for ripening date, berry size, sugar content and acidity should be very effective. Second, there were no significant family by harvest season interaction effects. Hence, selection based on single year’s data was as effective as that based on two years’ data. Third, selection based on individual characteristics could be hindered by negative genetic correlations. Hence it would be unwise to select a vine based on only one or two characteristics as this may have unfavourable impacts on other traits. For example, berry weight was negatively with juice sugar concentration. 4. Varietal release Three new varieties have been released with PBR protection (i.e. the early ripening white seeded Muscat, M 5118 , the mid-season black seedless type, M 1301 and the mid-late ripening white seedless, M4414 ; Figure 1). Marketing involves use of trademarks for fruit of the new varieties that meet quality specifications (i.e. Millennium MuscatTM, Magic Seedless® and Mystic SeedlessTM for the three new varieties, respectively). M 51-18 produces very early ripening, white seeded grapes that develop a distinct muscat character. It is being grown in the sub-tropical Carnarvon region of Western Australia for domestic markets. M 1301 produces very attractive loose bunches with green stems and large natural berries (5-7g) and does not require GA treatments. It is grown in most regions for both domestic and export markets. The latest release, M 4414 (Clingeleffer et al., 2011), produces large, crisp, seedless berries and is suited to long-term cool storage. It requires GA treatments for thinning and GA and CPU treatments for berry sizing to give a 5-7g berry. 40 7th International Table Grape Symposium Figure1. Views of the varieties released from the program, i.e. M 5118 (left), M 1301 (centre) and M 4414 (right). ORAL SESSION 3 5. Current status of the program No new breeding has been undertaken since 2008. Material retained for evaluation includes 630 seedless single vine seedlings, 210 multiplied selections and 21 seedless selections identified with promise for evaluation at regional sites. The latter material includes 12 white (one with strong muscat character), 6 red and 1 black selection with natural berry weights ranging from 4-6g without the use of GA. A further 3 early ripening selections (1 white, 1 red and 1 black selection) are established on grower sites for semi-commercial evaluation. Discussion and Significance of the Study A national table grape breeding and evaluation has been conducted for 16 years in Australia. New breeding has generated new genotypes which have been established in the field for evaluation. A number of seedless selections have been identified with significant potential for further evaluation and commercial development. The national evaluation of selections with high potential in the major growing regions has enabled assessment to be conducted in a diverse range of climates with varying seasonality and management practices. Three new varieties, the early ripening the white seeded muscat M 51-18 , the black seedless selection, M 13-01 and the white seedless M 44-14 have been released from the program. New knowledge concerning the inheritance of key characteristics, improvements for in-ovulo embryo rescue and rapid screening for disease resistance have been incorporated into the program. Acknowledgements The authors wish to acknowledge the financial support since 1998 from state and regional grower associations for their voluntary contributions, Horticulture Australia and the in-kind contributions of collaborating research agencies and growers with trial sites. Significant guidance has been provided by members of the national project steering committee, the commercialisation sub-committee and the Australian Table Grape Association. The significant input from all project research officers across the collaborating research is gratefully acknowledged. References Clingeleffer PR. 2005. Table grapes for the new Millennium. Final report, project FR 97047, Horticulture Australia Ltd. Clingeleffer, PR. 2010. Table grapes for the 21st Century, Final report, project TG 03008, Horticulture Australia Ltd. Clingeleffer PR. 2013. Table grapes for the changing and variable Australian environment that address marketing needs. Final report, project TG09003, Horticulture Australia Ltd. Clingeleffer PR, Powell RL, Wei X, Ganeshan D, Walker RR and Sykes SR. 1999. Table grapes for the new millennium: an overview of CSIRO’s table grape breeding program including new developments. Jacka, L. (ed.). Table grapes into the next century: proceedings of the 5th Australian Table Grape Technical Conference, 43-47. Clingeleffer PR, McCarthy BV, Liu SM, Sykes SR and Walker RR. 2003. Breeding table grapes for the 21st century. In: Jacka, L., compiler. Proceedings of the 6th Australian Table Grape Growers Technical Conference. Mildura, Vic.: Murray Valley Table Grape Growers Council: 27-310. 7th International Table Grape Symposium 41 Clingeleffer PR, McCarthy B, Cameron I, Gordon C, Oag D, Sykes S and Walker R. 2009. New Australian table grapes to meet consumer needs. In: Proceedings, 7th Australian Table grape Conference. Rising to the challenge, Mildura, September 2009. 12-14. Clingeleffer PR, McCarthy B, Gordon C, Cameron I, Oag D, Sykes S and Walker R. 2011. New white seedless table grape, M 44-14, released. The Vine 7(1): 32-33. Clingeleffer PR, Emanuelli DE, Tarr CR, Singh DP, Sykes SR and Walker RR. 2011. M48-42 (Syn. Black Gem), a new early ripening, disease tolerant currant variety. The Vine 7(3): 32-33. Liu S, Sykes SR and Clingeleffer PR 2003a. Improved in-ovulo embryo culture for stenospermic grapes (Vitis vinifera L). Australian Journal of Agricultural Research 54: 869-876. Liu S, Sykes SR and Clingeleffer PR. 2003b. A method using leafed single node cuttings to evaluate downy mildew resistance in grapevines. Vitis 42: 173-80. Liu SM, Sykes SR, Clingeleffer PR. 2008. Effect of culture medium, genotype, and year of cross on embryo development and recovery from in vitro cultured ovules in breeding stenospermocarpic seedless grape varieties. Australian Journal of Agricultural Research 59(2): 175-82. Liu SM, Sykes SR, Clingeleffer PR. 2008. Variation between and within grapevine families in reaction to leaf inoculation with downy mildew Sporangia under controlled conditions. Vitis 47: 55-63. ORAL SESSION 3 Sykes SR, Clingeleffer PR, Wei X and Walker RR. 2001. Developments in table grape breeding. Australian Grapegrower and Winemaker 449a: 119-122. Wei X, Sykes SR and Clingeleffer PR. 2002. An investigation to estimate genetic parameters in CSIRO’s table grape breeding program. 2. Quality characteristics. Euphytica 128: 343-351. Wei X, Clingeleffer PR and Sykes SR. 2003a. Narrow-sense heritability estimates for yield and quality characteristics in CSIRO’s table grape breeding progam. Acta Horticulturae 173-179. Wei X, Sykes SR and Clingeleffer PR. 2003b Effects of selection on early stage genetic evaluation for berry weight in breeding table grapes. Plant Breeding 122(1):77-82. 42 7th International Table Grape Symposium Apulia Seedless: Description and effect of cultural practices Pietro Scafidi1,*, Bartolomeo De Tommaso2, Cesare La Sorella2, Stefano Somma2 and Rosario Di Lorenzo3 Agriproject Group Australia Pty Ltd, 14 Bertram Road - Euston NSW 2737 Grape&Grape, Via delle Orchidee, 20 - Rutigliano (Bari), Italy 3 Dipartimento di Scienze Agrarie e Forestali – University of Palermo – Viale delle Scienze 11, Palermo, Italy *Corresponding author: Tel: +393454635161, Email: [email protected] 1 2 Background and Aims Apulia is an Italian red seedless variety (UE registration 2008/1662), resulting from the crossing of Emperor and Thompson Seedless. The cultivar was obtained by Stefano Somma and was released in 1996. ORAL SESSION 3 Apulia is a late season variety, in Italy budbreak (BBCH 08) usually occurs at beginning of April (2-3 days after Crimson), full bloom (BBCH 65) at mid-May (5-6 days before Crimson), ripening from late September to mid-October, and the grape can stay on the vine until mid-December. The cluster naturally is long, conical with large shoulders. The rachis is green and strong, the link to the shoot is woody at harvest. Apulia produces red firm berries strongly linked to the rachis (berry removal force: 4.17 N). The berry has generally spherical shape, medium size (average mass of 5.5g), and herbaceous rudimentary seeds. At ripening the taste is neutral, having low total acidity (below 4.6g.L-1 of Tartaric acid) and a TSS/TA ratio between 25 and 30. Apulia is characterised by high and even bud fertility (1.76 bunches per shoot) and elevate plant vigour. It is well adapted to be grafted onto Vitis berlandieri x Vitis rupestris rootstock (1103P, 140Ru), commonly trained on V trellis, it is spaced 2.40m between vines and 3m between rows. Usually, Apulia is pruned on canes (4 canes of 10/12 buds), although, taking in consideration the high bud fertility, quadrilateral cordon training and spur pruning could be suggested for good productivity and easy management. In Italy, the application of GA3 during bloom to reduce fruit set is not necessary, due to the adequate number of flowers that set. In some seasons, the first bunch shoulder (widow) could present a poor set, in that situation a good bunch appearance could be obtained removing it. The natural production potential is very high, considering that without any crop-load management it is possible to have 48-60 bunches per vine and the bunch weight can be easily over 850 grams (55-70 tons per hectare). Preliminary results show that Apulia responds well to crop load reduction (cluster thinning to 36-40 bunches per vine) and bunch manipulation. Crop control should be done just after berry set. As already found in other varieties, bunch trimming has a primary effect on berry size but it might improve colour uniformity. Trunk girdles applied at the end of berry set (6-7mm berry diameter) could increase the berry weight but also delays fruit maturity, prolongs harvest and increases the chances of berry splitting. Girdle applied at berry softening or véraison has no effect on fruit ripening and berry size. As a result, this treatment is generally not recommended. No studies have been carried out on the effect of plant grow regulators (PGRs) application on Apulia. The purpose of this study was to evaluate the potential use of PGRs to increase natural berry size without compromising the quality of fruit. Experimental Procedure and Results Five-year-old Apulia grapevines (Soc. Coop. Agricola Ponterosa, Taranto, Italy) of similar capacity and crop load, grafted onto 140 Ru rootstock were used in this study. Each vine was trained by a gable trellis and cane pruned. The vines were spaced 2.4m within rows and 3m between rows. The vineyard was drip irrigated and standard cultural practices were followed, including basal leaf removal, shoot and bunch thinning. The bunch number per vine was adjusted at 45 bunches. Four treatments were imposed: 1. 5ppm CPPU (Sitofex® Forclorfenuron 7.5g.L-1 - AlzChem Trostberg); 2. 5ppm GA3 (Gibersol Giberellic Acid 47.8 g.L-1 - CIFO); 3. 5ppm CPPU + 5ppm GA3 4. Untreated 7th International Table Grape Symposium 43 Each treatment was randomly replicated three times on three adjacent rows (3 field replicates of 5 vines). All PGRs were applied when approximately the berry diameter was between 10 and 12mm (17 June 2013). The PGRs were applied directly to the clusters with a handheld sprayer until runoff. At harvest, 5 bunches were sampled from each field replicate and weighed. On 10 berries, randomly selected per bunch (50 berries per field replicate; 150 berries per treatment), the removal force was measured. Others 10 berries were randomly selected from each cluster (50 berries per field replicate; 150 berries per treatment) and they were clipped using shears, leaving the pedicel attached to the berries. Each field replicate was analysed independently. Berry breaking force was tested, by measuring the force, expressed in Newton (N), required to compress a berry through a needle probe (8mm diameter) to crack it. Total soluble solids (TSS) were measured using a digital refractometer in juice obtained by squeezing, homogenising and filtrating peeled berries. Titratable acidity, expressed as grams of tartaric acid per 100ml, was determined by titrating the berry juice with a sodium hydroxide solution. ORAL SESSION 3 The surface colour of berries in each sample was measured with a reflectance colourimeter (CR-200, Minolta Inc., Ramsey, NJ), using the CIELAB colour system, where L* is the lightness and corresponds to a black-white scale (0, black; 100, white), h° is the hue angle on the colour wheel, and C* is the chroma, a measure of the intensity of colour, which begins at zero (achromatic) and increases in intensity. Two colour measurements were made around the equator of each berry. Means and standard errors were reported. Analysis of variance (ANOVA) and Tukey’s HSD test was used at a 5% level of significance (α=0.05). All statistical analyses were performed using SYSTAT® 12. Results: PGRs had a clear effect on berry weight. Berry weight was significantly higher in the bunches treated with 5ppm CPPU + 5ppm GA3 (6.67g), followed by berries treated only with 5ppm CPPU (6.14g) and 5ppm GA3 (5.80g). The Natural berries were significantly smaller (5,46 g; -18% than 5 ppm CPPU + 5 ppm GA3) (Table 1). Also berry diameter followed the same trend of berry weight, meanwhile only bunches treated with 5ppm CPPU + 5ppm GA3 had a significantly higher weight. All the other treatments did not show any significant difference in bunch weight (Table 1). Table 1. Effect of PGRs applications on berry and bunch characteristics. Treatment Natural CPPU GA3 CPPU + GA3 Berry weight (g) Berry diameter (mm) Bunch weight (g) No. of berries per bunch Mean 5.46 d 20.17 d 835.69 bc 153.20 ± s.e. ± 0.06 ± 0.10 ± 24.38 ± 8.85 Mean 6.14 b 21.09 b 890.9 ab 145.70 ± s.e. ± 0.08 ± 0.14 ± 26.20 ± 9.24 Mean 5.80 c 20.47 c 864.2 b 149.10 ± s.e. ± 0.11 ± 0.13 ± 26.54 ± 8.63 Mean 6.67 a 22.04 a 913.47 a 145.90 ± s.e. ± 0.09 ± 0.20 ± 18.30 ± 10.94 * ** ** n.s. ** and * indicate, respectively, statistically significant differences at P = 0.01 and 0.05; n.s. indicates no significant differences. Means followed by different letters were significantly different at P = 0.05 using Tukey’s HSD test. CPPU applications, significantly affected fruit mechanical characteristics and the highest values were recorded when it was sprayed by its own. Specifically, for berry breaking force and berry removal force values of 34.59 and 5.28N were measured in CPPU treatment, against values of 28.67 and 4.17N in Natural and of 22.43 and 4.32N in GA3. In berries treated with 5ppm CPPU + 5ppm GA3 a cumulative effect of the PGRs was found, and the values of berry breaking force and berry removal force were in the middle between treatment with only CPPU and GA3 but still higher than Natural. (Table 2). 44 7th International Table Grape Symposium Table 2. Effect of PGRs applications on berry physical properties. Treatment Natural CPPU GA3 CPPU + GA3 Removal force (N) Berry breaking force (N) Mean 4,17 b 28,67 b ± s.e. ± 0,25 ± 1,42 Mean 5,28 a 34,59 a ± s.e. ± 0,22 ± 1,67 Mean 4,32 b 22,43 c ± s.e. ± 0,30 ± 1,41 Mean 4,57 ab 28,90 b ± s.e. ± 0,23 ± 1,55 * * ** and * indicate, respectively, statistically significant differences at P =0.01 and 0.05; n.s. indicates no significant differences. Means followed by different letters were significantly different at P=0.05 using Tukey’s HSD test. ORAL SESSION 3 The total solid soluble (TTS) content was always lower in berries treated with CPPU, sprayed by its own or mixed with GA3, than in other treatments. GA3 application, instead, didn’t affected total soluble solids accumulation (Table 3). In consequence of above, also the ratio of TSS to TA was affected, and significantly higher values of TTS/TA were found after CPPU applications. At harvest, berries of different treatments had not significantly different values with respect to h°, L*, and C* (data not shown). Table 3. Effect of PGRs applications on berry chemical properties. Treatment Natural CPPU GA3 CPPU + GA3 Total Soluble Solids (°Brix) TSS/TA Mean 17,88 a 28,82 a ± s.e. ±0,05 ±0,48 Mean 16,25 b 25,10 b ± s.e. ±0,03 ±0,44 Mean 17,83 a 27,97 a ± s.e. ±0,14 ±0,15 Mean 16,85 b 25,97 b ± s.e. ±0,40 ±0,58 * * ** and * indicate, respectively, statistically significant differences at P = 0.01 and 0.05; n.s. indicates no significant differences. Means followed by different letters were significantly different at P = 0.05 using Tukey test. Discussion and Significance of the Study As was predictable, PGRs application improved berry weight and diameter. Many studies demonstrated that most seedless table grapes, when are treated with gibberellic acid (GA3) or CPPU increase berry size and uniformity (Peppi and Fidelibus, 2008; Diaz and Maldonado, 1992; Dokoozlian et al., 1994; Reynolds et al., 1992; Wolf et al., 1994). The highest value was recorded under the treatment with 5ppm CPPU + 5ppm GA3. These results are in agreement with findings of Retamales and colleagues (1995), that reported CPPU, used in combination with GA3 at the same timing, improved berry size in experiments conducted over 4 years on Sultanina grape. CPPU improved berry removal force and fruit firmness, especially when it was sprayed by its own. (Dokoozlian et al., 1994; Reynolds et al., 1992; Wolf et al., 1994; Zabadal and Bukovac, 2006). Soluble solids were decreased by CPPU application, in agreement with others authors (Peppi and Fidelibus, 2008; Dokoozlian et al., 1994, Reynolds et al., 1992), but changes were not enough to change probable harvest date of the fruit. It is notable that grapes treated with CPPU or GA3 had essentially the same colour as untreated grapes, confirming that Apulia Seedless has good genetic colouring potentiality. 7th International Table Grape Symposium 45 In conclusion, the combined use of CPPU and GA3 has the potential to improve the quality of Apulia Seedless table grapes because they are generally effective at increasing berry size and the physical properties of the grape and meanwhile the negative effects of CPPU on maturity, and particularly on sugar content and skin colour, can be negligible. References Diaz DH and Maldonado LA. 1992. Forchlorfenuron effects on berry size and maturity of Perlette and Flame Seedless grapes. Proceedings of the Plant Growth Regulator Society of America. Annual Meeting 19:123-128. Dokoozlian NK, Moriyama MM, Ebisuda N. 1994 Forchlorfenuron (CPPU) increases the berry size and delays the maturity of Thompson Seedless table grapes. International Symposium on Table Grape Production Proceedings Anaheim. American Society for Enology and Viticulture. pp 63-68 Peppi MC and Fidelibus MW. 2008. Effects of Forchlorfenuron and Abscisic Acid on the Quality of ‘Flame Seedless’ Grapes. Vol. 43 No. 173-176. Retamales J, Bangerth F, Cooper T, Callejas R. 1995. Effects of CPPU and GA3 on fruit quality of Sultanina table grape. ISHS Acta Horticulturae 394: Plant Bioregulators in Horticulture ORAL SESSION 3 Reynolds AG, Wardle DA, Zurowski C, Looney NE. 1992. Phenylureas CPPU and thiadiazuron affect yield components, fruit composition, and storage potential of four seedless grape selections. Journal of the American Society for Horticultural Science 117: 85-89. Wolf EE, Viljoen JA, Nieuwenhuys A, Loubser JT. 1994. The effect of forchlorfenuron on bunch quality in table grapes. International Symposium on Table Grape Production Proceedings Anaheim. American Society for Enology and Viticulture. pp 50-53. Zabadal TJ and Bukovac MJ. 2006. Effect of CPPU on fruit development of selected seedless and seeded grape cultivars. HortScience 41:154-157. 46 7th International Table Grape Symposium What can we learn from the table grape breeding program in Israel? E Raban1, I Maoz2, T Kaplunov2, Y Zutahy2, A Daus2, O Degani2, A Perl2 and A Lichter2,* Extension Service, The Ministry of Agriculture, Bet Dagan, Israel ARO, The Volcani Center, POB 6, 50250, Bet Dagan, Israel *Corresponding author: Tel: 972 3 9683684, Email: [email protected] 1 2 Background and Aims The breeding program of the Volcani Center is focused on seedless table grapes but the high genetic variability between the breeding lines, the large number of lines tested and the systematic collection of quantitative trait data offers new insights which are difficult to obtain by analysis of individual varieties. The breeding lines are treated by standard program of table grape cultivation in Israel and by plant growth regulators (PGRs) to enlarge the berries. However, PGRs are known to delay ripening as expressed by either delayed accumulation of brix or by delayed colour development. It is therefore of interest to find out if the effect of PGRs on ripening are general. ORAL SESSION 3 Another focus of breeding program is flavour which has been somewhat neglected. All breeding lines of sufficient quality are tested for flavour by trained panels. The content of volatiles in the breeding lines is analysed to identify unique profiles. Experimental Procedures and Results Data was collected during 2012 and 2013. Ten vines of each breeding line were grown under standard practice. Five vines were treated by a combination of 20ppm gibberellin and 1ppm of the cytokinin CPPU. At maturity 10 clusters were harvested from each treatment and were analysed for cluster and berry weight, firmness, uniformity, berry shot, shatter, juice colour, acidity, brix and flavour. Flavour analysis was carried out by trained panel that graded the grapes for various parameters. Juice was frozen for GC-MS analysis and volatile composition was analysed. Specific breeding lines of interest will be presented. As expected, PGRs increased the size of most lines. Unlike common knowledge, PGRs increased juice colour intensity in most of the breeding lines. With regard to flavour preference it was observed that sugar and acidity explained only part of the flavour preference. Analysis of volatiles revealed that some lines were very reach in different compounds which can be significant for flavour while other lines including commercial control lines were very poor in volatiles. The volatiles could be divided into a basic profile which was present in most of the lines and unique profile which was present in only few lines with some lines having unique characteristic volatiles. Table 1: The effect of PGRs on juice colour. The number of lines showing significantly reduced or enhanced colour as compared to the control. PGR< Control PGR>Control 2012 0/12 4/12 2013 2/14 8/14 Discussion and Significance of the Study The effect of PGRs on fruit colour is interesting and worth further research and tracing of the phenomenon to parent lines. The intensive flavour analysis should yield breeding lines of better flavour which are not compromised for the basic traits. Data elaboration should yield understanding of which aroma compounds are of significant value and incorporation of this knowledge into the breeding program. Acknowledgement We thank the Table Grape Board – The Plant Council, Israel for the financial support and the taste panelists for their significant contribution. 7th International Table Grape Symposium 47 Session 4. Rootstocks, breeding and cultivar improvement (Continued) Keynote address Using novel genetics to breed unique new table grape varieties John R Clark Department of Horticulture, Plant Science 316, University of Arkansas, Fayetteville, Arkansas, 72701 USA, Email: [email protected] Background and Aims On August 3, 2013, one of the major national morning news shows in the US, Good Morning America, had a leading story that began….”First, they put a man on the moon. Then, they invented cell phones. Now, this morning another major breakthrough for mankind. A fruit breeder in California has invented grapes that taste like allegedly cotton candy.” And, two days prior, the Los Angeles Times had a front page story “Cotton Candy off the vine”. It is rare that a fruit breeding story gets national press such as this. I want to share with you a little of the story about this and unique table grape germplasm utilisation. ORAL SESSION 4 Diversity in table grapes is increasing due to incorporation of new traits into new variety products in a number of innovative breeding programs in the world. I have been involved with a very exciting cooperation that involves diversification of traits since 2002 between the University of Arkansas and International Fruit Genetics (IFG) of Bakersfield/Delano, California. The University of Arkansas table grape breeding effort began in 1964, started by Dr. James N. Moore (Clark, 2010). I came to the University of Arkansas as a research technician and PhD student in 1980, and have worked in the program ever since, taking Dr. Moore’s place upon his retirement in 1996. The program has been carried out in the middle of the country, in the upper south. Several key environmental characteristics include rainfall of 1,100mm per year (with rain each month), hot summer temperatures of 35°C in most summers, winter minimum temperatures of -15°C, and some risk of spring frost leading to emerging shoot damage. There is a substantial group of biotic challenges at this site including a range of diseases such as black rot (Guignardia bidwellii Viala & Ravaz), powdery mildew (Erysiphe necator Schw. (syns. Uncinula necator (Schw.) Burr., E. tuckeri Berk., U. americana Howe, and U. spiralis Berk. & Curt; anamorph Oidium tuckeri Berk.), downy mildew (Plasmopara viticola Berl. & de Toni), and anthracnose (Elsinoë ampelina Shear) and several insects including grape berry moth (Paralobesia viteana Clemens). These biotic and abiotic factors have provided for substantial selection pressure for winter hardiness, fruit cracking, and to some degree disease resistance. However, the breeding material has been sprayed with fungicides for the life of the program due to the intense disease pressure coupled with the lack of high enough disease resistance to allow a non-spraying approach to program management. Dr. Moore’s dream was to develop primarily table grape varieties to create an eastern US table grape industry. There was also a minor effort in breeding juice and wine grapes. The germplasm used in the program has been much different than that used in the Vitis vinifera L. table grape breeding programs in California or other locations in the world where this is the sole species grown. Vitis vinifera is not well adapted in Arkansas due to lack of winter hardiness, disease susceptibility, and fruit cracking limitations. To develop successful varieties, other sources of adaptation were required. A primary source was V. labrusca L., an eastern US native species. This species offers better adaptation including winter hardiness, disease resistance, fruit cracking resistance, and a new flavour profile. It also introduces limitations such as soft, slip-skin texture, thick skins, more procumbent growth habit, and flavours that can be overwhelming for some palates. Over the years, it was found that the higher the quality including thin skins with crisp texture, the less adapted the vines were as shown by winter injury and fruit cracking. The program has produced 10 table grape varieties, mainly targeted for local-market use in the eastern US. These include Reliance, Mars, Jupiter, Neptune, and the newer Faith, Hope, Joy, and Gratitude (Clark, 2010; Clark and Moore, 2013). However, none have the level of fruit characteristics (particularly crisp texture, fruit cracking resistance, and large berry size) required of commercial V. vinifera varieties found in the national table grape market. 48 7th International Table Grape Symposium However, the University of Arkansas was not the first public entity to breed table grapes with V. labrusca. The New York Agricultural Experiment Station began grape breeding in the early 1900s, mainly using eastern genotypes. The release in 1952 of Himrod (resulting from a cross of Ontario x Sultanina (Clark, 1997). This was one of the first seedless grapes developed in the eastern US, and combined qualities of both species for a local-market-type grape. Himrod did not have quality comparable to California developments. The Arkansas program used a number of the New York developments as parents in early crossing. Much later, Dr. David Ramming with the United States Department of Agriculture – Agricultural Research Center in California in 1983 crossed Thompson Seedless x Concord (the main US juice grape variety), and released Thomcord from this progeny in 2003 (Ramming, 2008). It too combined characteristics of each species. Experimental Procedure and Results Dr. David Cain visited me in Arkansas in the summer of 2001. Dr. Cain had just started his new IFG fruit breeding program in California, and was very familiar with the Arkansas grape breeding effort as he had visited the program at various times over the years. Dr. Cain was very experienced in table grape breeding, but he needed an expansion of breeding germplasm to complement the V. vinifera material he was crossing with. He shared the idea of incorporating the Arkansas program achievements (selections developed but not released) into his IFG effort. At first, I was not sure of the feasibility of this idea, as cooperation between public and private fruit breeding efforts has been rare in the US or other locations in the world. However, an agreement was made between the University and IFG, and the University material was shared with IFG and crossing was begun in 2002. ORAL SESSION 4 What was Dr. Cain interested in with the Arkansas material other than a broadening of the germplasm of the IFG breeding program? He knew that there were several traits in the program that could be innovative including new flavours, shapes, skin cracking resistance, seedlessness, and overall broader adaptation that might be incorporated for use in California or other locations in the world. He also knew that there had been almost 40 years of focused breeding in Arkansas to enhance quality of largely V. labrusca-derived table grapes, never done before in the history of table grape breeding in the US. His ‘genius’, as I like to say, led to the discoveries he has made at IFG. Discussion and Significance I remember visiting Dr. Cain when he fruited the first seedlings that incorporated the Arkansas material with pure V. vinifera germplasm. I was very impressed with the initial progeny, in that he was able to achieve very good fruit size and quality in the seedlings in the first-generation crosses. I was not sure the path these might take toward possible commercial use, but was excited to see the initial products particularly after so many years of evaluating table grapes in Arkansas where the environment limited the potential quality achievements compared to the California climate. One of these early seedlings resulted in the selection that later was commercialised under the trademark Cotton Candy®. This development incorporated the largely Arkansas-derived flavours (a blend of V. labrusca and muscat) with large berry size and crispness of V. vinifera, with quality comparable to the more neutral-flavoured V. vinifera cultivars. He also produced many more selections with unique flavours, providing for an entirely new range of genotypes for potential commercialisation. And, key to this was the enhanced quality combined with the flavours, never done in table grape breeding prior. The Arkansas program also focused on elongated shapes. This was done by crossing among semi-elongated to elongated selections, and selecting those with a greater expression of this trait. Elongated shapes have also been developed in other programs in the world, but likely not from the same genetic basis as done in Arkansas. Dr. Cain used the elongated selections in crossing, and developed the trademarked Witches Fingers product now marketed to a limited extent in the US. How did this innovation in table grape breeding come about? As I have told the story over the years, there are a few key components for this and most successful plant breeding commercial achievements: someone with a vision and inspiration, a source of genetic variation of desirable traits, and an approach to marketing the resulting product. Public agency plant breeding cooperation has undergone increasing difficulty in the last 25 years due to the tightening of germplasm exchange among programs. Methods of sharing germplasm through formal agreements offer a pathway to encourage germplasm exchange. The IFG and Arkansas example is one where public and private exchange was possible. And, the results have been very exciting: IFG acquired diverse germplasm resulting in innovative products, the University of Arkansas has been able to have its decades-long breeding effort be utilised in more mainstream table grape breeding. Plus, the University benefitted from program support from IFG, support that was lacking before due to a lack of a local industry. 7th International Table Grape Symposium 49 What will these innovative products from IFG contribute to table grapes in the short and long term? I am not in a good position to say for sure. Coming from the eastern US, I am very familiar with more diverse flavours in grapes beyond the more neutral flavours of V. vinifera along with the V. vinifera muscat flavour. First and foremost, I am excited to see table grape consumers have more diversity in products to enjoy. Furthermore, I am a strong believer that table grapes deserve more and more product identity by variety and or brand in the marketplace, not simply green, red, and black groupings common in most US retail markets. We can only look to our apple colleagues to see the value of variety differentiation in the marketplace. Of course, with this differentiation will come increasing limitations in the availability of new varieties to all growers. That appears to be inevitable for a number of reasons, one being to provide a way to fund the substantial breeding program costs. As I impress on plant breeding students, recognising diversity in breeding germplasm and in potential products is one of the most exciting aspects of plant improvement. Diversity in the customer base is an opportunity, not an insurmountable challenge that can’t be taken advantage of. There is likely a large number of people that will be excited about and enjoy diverse table grape flavours once they get to try these. I believe this is one of the most exciting times in table grape breeding, and I appreciate the opportunity to have a small part in this ‘show’, and share my experiences and comments. References Clark JR. 2010.Eastern United States table grape breeding. Journal of the American Pomological Society 64:72-77. Clark JR. 1997. Grapes. Pp. 248-299. In: Brooks and Olmo register of fruit and nut varieties, third edition. ASHS Press, Alexandria, Va. Clark JR and Moore JN. 2013. Faith, Gratitude, Hope, and Joy seedless table grapes. HortScience 48:913-919. Ramming DW. 2008. ‘Thomcord’ grape. HortScience 43: 945-946. ORAL SESSION 4 50 7th International Table Grape Symposium Addressing challenges in the global development of proprietary varieties through applied varietal research Hovav Weksler* Sun World International LLC, 5701 Truxton Avenue, Suite 200, Bakersfield CA USA 93309 *Corresponding author: Tel: 972 2 9910781, Email: [email protected] Background and Aims Sun World International is based in California and is a grower, marketer and breeder of table grapes amongst other crops. The company has over 4,000 hectares of farming land and around 1,000 domestic and international licensed partner growers, and is directly involved with the farming, packing, marketing and distribution operations for a large part of its US grown produce. For many years Sun World has differentiated itself in the produce industry as the sole producer and marketer of proprietary varieties developed at the company’s Variety Development Center but then, at around year 2000, Sun World launched its global licensing program by partnering with leading growers and marketers throughout the world which by today reached around 9,000 hectares of fruit varieties grown in all continents, ensuring year-round supply of proprietary varieties to premium markets. ORAL SESSION 4 To manage such a large network, licensing offices were established in Chile, Italy, South Africa Australia and Mexico, and professional grower and marketer licensees were picked to ensure that the proprietary varieties are grown, harvested and delivered to the company’s high specifications. Licensees are provided with the technical and marketing support they need to succeed in today’s competitive global market, including on-site consultant visits, special group field days and international expos, fruit trial results (from weekly held taste panel evaluations) with updates on new varieties in the pipeline, and more. Through a special Licensee web portal licensees are offered exclusive access to cutting-edge research and information about new varieties and, finally, licensed marketers and growers are connected so they can work together to efficiently deliver produce to markets worldwide. All that support is offered to licensees because knowledgeable growers and marketers are more successful and because their success is Sun World’s success as well. The Applied Varietal Research (AVR) program officially started at Sun World in May 2013 although field trials and applied research have routinely been carried out by the company’s R&D and technical staff prior to that. The primary objectives of the AVR program were to address technical issues that might potentially limit the profitability of existing globally widely planted varieties as well as to develop best cultural practices for newly released varieties prior to their commercialisation by Sun World and by its licensees. The logic behind establishing a target oriented unit within the company to address those issues was that even the best varieties, once globally commercialised in numerous sites and grown under various conditions that are totally different from where they were bred, are expected to exhibit challenges that would require application of specific practices in order to make them successful. While for existing varieties the AVR program is expected to develop curative protocols for each identified challenge, for new varieties the objective is to develop preventative protocols against potential risks and to shorten the learning curve’s period at new production sites. Procedures and Results The program’s initial objectives were to identify technical challenges with Sun World’s commercially grown proprietary varieties, suggest a research program to address those issues and establish a global network of agronomists to work on it through coordinated research under the AVR program. Noted challenges were sugar enhancement in early varieties, season stretching in late varieties, thinning in specific varieties, colour improvement and decay prevention. While some of the challenges were known beforehand, especially on older varieties, valuable information was gathered through preliminary discussions with producers, marketers and advisors which were then used to prioritise the challenges and set up a detailed research program which included over 50 trials in eight countries last year. Standardisation of the trials between the various countries was achieved through practicing similar procedures with regards to design, setup, application and evaluation methods, forms used and analysis of the results. Half day seminars were conducted in various countries during which results were presented and their significance was discussed with local producers and marketers. Additional information distribution channels such as webinars, discussion groups, library establishment, Q&A and others are yet to be developed. 7th International Table Grape Symposium 51 Discussion and Significance of the Program While still at its first steps of establishment, the AVR program has gained much interest amongst Sun World’s licensees who look at it as a tool that can be used to create information, distribute it and effectively integrate it. The company’s presence in both the southern and the northern hemispheres allows for the accomplishment of two research seasons in one calendar year which saves precious time and which has already contributed to making progress in some of the highly prioritised challenges. The program’s success, in Sun World’s eyes, is expected to not only improve the immediate profitability of the company’s proprietary varieties but also to strengthen the licensees’ confidence in Sun World’s breeding and licensing program in general. Acknowledgement We thank all the many dedicated licensed growers and marketers in Chile, Brazil, Australia, South Africa, Spain, Italy, California and Israel who contributed their vineyards, ideas, energy and time to this program. Without their support this program could not have taken off the way it did. ORAL SESSION 4 52 7th International Table Grape Symposium Effect of rootstocks on leaf nutrient composition of Vitis vinifera cvs. Superior Seedless and Red Globe María Beatriz Pugliese1,*, Sergio Vega Mayor2, Franco Pugliese2, Rodrigo Espindola2, Pedro Gil1, Sergio Mundaca1 and Lisando Bustos1 INTA EEA Pocito, Calle 11 y Vidart, San Juan, Argentina INTA AER Caucete, San Juan, Argentina * Corresponding author: Tel: 54 264 4921079, Email: [email protected] 1 2 Background and Aims There is a lack of information in Argentina about the use of rootstocks for table grapes, although there is some information available on the effects of rootstock such as resistance to soil borne pests and diseases, vigour, production and fruit quality. There is also insufficient information available regarding interactions between the scion cultivar, the rootstock and the nutrient status of grapevines (Vitis vinifera L.) (Ibacache and Sierra 2009, Morales et al., 2013), although several studies have shown that rootstocks affects the nutritional status of the scion cultivar (García et al., 2001, Ibacache and Sierra 2009, Morales et al., 2013). The aim of this work was to evaluate the effect of six and eight rootstocks on the leaf nutrient/element composition of Vitis vinifera cvs. Superior Seedless and Red Globe, respectively. Experimental Procedure and Results ORAL SESSION 4 The study was conducted for five consecutive seasons from 2008/09 to 2012/13. The Red Globe trial was done at Pocito locality, San Juan (31° 37´S; 68° 32´ W) on clay loam soil whereas the Superior Seedless was done at Caucete locality, San Juan (31° 39,5´S; 68° 16,54´ W) on sandy loam soil. The trellis system was a Parral (Pergola) with a vine spacing of 2.5 x 2.5m and 3.0 x 3.0m for Red Globe and Superior Seedless respectively. Drip irrigation was applied in both sites. The treatments were: Red Globe, grafted onto the rootstocks, Cereza (Vitis vinifera L.); Salt Creek (Ramsey); 140Ru; 101-14 Mgt; Harmony; Freedom; SO4 and Control (vines grown on their own roots). Superior Seedless, grafted onto the rootstocks, Salt Creek; 140Ru; 1103P; 101-14 Mgt; Harmony; Freedom; SO4 and Control. The experimental design was a randomised complete block design, with four replicates and two vines as at experimental unit. Whole leaves (leaf blade and petiole) opposite the clusters were collected at véraison stage. The sample contained 80 whole leaves per treatment in each replicate. The total concentrations of N, P, K, Ca, Mg, Na, B, Fe, Mn, Zn, Cu were determined for each of the samples and were used as a reference for interpreting optimal and excessive nutritional levels Silva and Rodríguez (1995). All leaf analysis was done at INTA EEA San Juan Laboratory. Data were analysed by ANOVA and the comparison of means were done by the Fisher LSD test, with a significance level of p≤ 0.05. Results: The whole leaf nutrient levels at véraison exhibited the highest N content for Red Globe on Harmony. Highest P levels were observed for both Red Globe on Freedom and Superior Seedless on Salt Creek and S04. Regarding leaf K content of both scion cultivars, the highest value was obtained with Harmony, while a suboptimal level was obtained with Red Globe on Own root and Cereza but with Superior Seedless it was Salt Creek. The highest Ca levels were obtained with Red Globe on Cereza with Superior Seedless on Salt Creek and SO4. Own root (both Red Globe and Superior Seedles) and Cereza rootstock (Red Globe) resulted in the highest Mg and lowest B content. Suboptimal Mg levels were obtained with Red Globe on S04, as well as Harmony and Superior Seedless on all rootstocks. The Fe levels of Red Globe were significantly lower on Cereza. Mn content was found to be highest with Red Globe on Cereza, Salt Creek, 140Ru, Freedom and SO4; as well as with Superior Seedless on Own root. The Cu content of, Red Globe grafted onto Salt Creek and SO4 was the highest. In the case of Na, higher levels was obtained with Own root (for both Superior Seedless and Red Globe) and Cereza with Red Globe as scion (Table 1 and 2). 7th International Table Grape Symposium 53 Table 1: Effect of rootstock on leaf element composition of Superior Seedless in Caucete, San Juan, Argentina. Data are averages for the seasons 2008/09 to 2012/13. Rootstock %N %P %K % Ca % Mg % Na B ppm Fe ppm Mn ppm Zn ppm Cu ppm Own root 2.33 0.16a 1.27bc 2.38b 0.32d 0.17b 57.44a 144.44 80.50c 36.69 9.88 Salt Creek 2.10 0.20c 1.10a 2.87c 0.24bc 0.14a 74.00bc 128.63 65.75bc 39.13 8.63 140Ru 2.20 0.17ab 1.26bc 2.23ab 0.23abc 0.13a 67.50ab 139.19 59.00b 36.13 9.38 1103P 2.19 0.17ab 1.23bc 2.14ab 0.25c 0.14a 78.88bc 133.06 42.88a 35.56 8.75 Harmony 2.28 0.18ab 1.66d 2.06a 0.23abc 0.14a 76.00bc 153.38 59.17b 36.19 10.75 Freedom 2.41 0.16a 1.31c 2.20ab 0.21ab 0.14a 63.94ab 150.38 40.44a 34.94 8.63 SO4 2.07 0.19bc 1.21b 2.69c 0.20a 0.13a 83.88c 132.50 66.50bc 37.25 8.50 Optimal level 1.82.4 0.2 1.2 1.5 0.3 40-60 50 30 30 4 Excessive level > 0.5 >300 Different letters mean significant differences in test LSD with p≤ 0.05. ORAL SESSION 4 Table 2: Effect of rootstock on leaf element composition of Red Globe in Pocito, San Juan, Argentina. Data are averages for the seasons 2008/09 to 2012/13. Mn Zn Cu Rootstock %N %P %K % Ca % Mg % Na B ppm Fe ppm ppm ppm ppm Own root 2.07ab 0.16cd 1.08a 2.77b 0.48f 0.19c 179.08a 139.94bcd 82.13b 31.25 7.08c Cereza 1.90a 1.09ab 3.65e 0.40e 0.17c 173.50a 110.44a 112.81c 32.94 6.08ab Salt Creek 1.99ab 0.16cd 1.23bc 3.10cd 0.31bc 0.11a 216.50ab 149.25cd 112.56c 33.75 8.33d 140Ru 2.05ab 0.16cd 1.37cd 3.05cd 0.37de 0.11a 226.75b 122.75ab 107.19c 32.00 5.67a 0.14a 101–14 Mgt 2.07ab 0.14a 1.43de 2.50a 0.30bc 0.14b 256.50b 141.75bcd 81.13b 33.94 6.33abc Harmony 2.27c 0.16cd 1.74f 2.30a 0.26b 0.14b 246.50b 159.56d 59.31a 37.75 7.17c Freedom 2.09b 0.17d 1.55e 2.90bc 0.34cd 0.14b 231.67b 153.81cd 101.44c 34.94 6.75bc SO4 2.13bc 0.14a 1.28cd 3.23d 0.19a 0.11a 237.83b 133.25bc 99.25c 31.67 8.63d 1.8-2.4 0.2 1.2 1.5 0.3 40-60 50 30 30 4 Optimal level Excessive level > 0.5 >300 Different letters mean significant differences in test LSD with p ≤ 0.05. Discussion and Significance of the Study This study demonstrated the effect of rootstocks on the leaf nutrient composition of two table grape scion cultivars. The results of this work, combined with information available on rootstocks’ resistance to soil borne pests and diseases, as well as vigour and influence on production and grape quality of the scion, would allow selection of rootstocks for particular soil and cultivation conditions. This study showed that American rootstocks resulted in the lowest scion Na leaf content. Therefore, it could be hypothesised that for soil with high sodium content, these particular rootstocks could be used. In this study, Cereza rootstock showed the highest levels of Ca and Mg and also exhibited highest production and grape quality (data not presented). 54 7th International Table Grape Symposium It is also important to highlight the behaviour of Vitis vinifera L., Red Globe and Superior Seedless on Own root and Cereza, with respect to the low B leaf content obtained, which could be potentially of practical value for agro climatic conditions where high B levels are present in both water and soil. Further studies are required to understand the influence of the rootstock on mineral absorption. Acknowledgements The authors would like to thank Yuaider D, Castro D, Morales O, Escudero E and Orosco G for their important collaboration in field trials. References García, M., Gallego P., Daverede C. and Ibrahim H. 2001. Effect of three rootstocks on grapevine (Vitis vinifera L) cv. Négrette, grown hydroponically. I. Potassium, calcium and magnesium nutrition. South African Journal for Enology and Viticulture 22:101-103. Ibacache A. and Sierra B.C. 2009. Influence of rootstocks on nitrogen, phosphorus and potassium content in petioles of four table grape varieties. Chilean Journal of Agricultural Research. 69(4):503-508. Morales M., Ferreyra R., Ruiz R., Zúñiga C., Pinto M., Sellés G. 2013. Effect of rootstocks on nutrient content in petioles of Thompson Seedless variety. IX International Symposium on grapevine Physiology and Biotechnology, La Serena, Chile. 184p. Silva H, y Rodríguez J. 1995. Diagnóstico del estado nutricional. Fertilización de plantaciones frutales. Colección en Agricultura. Facultad de Agronomía, Pontificia Universidad Católica de Chile. Santiago, Chile. 406p. ORAL SESSION 4 7th International Table Grape Symposium 55 Performance of Autumn King and Scarlet Royal table grapes on some standard, and more recently released, rootstocks Matthew W Fidelibus1,, Jennifer Hashim-Maguire2 and Donald A. Luvisi3 Department of Viticulture and Enology, University of California, Davis, CA 95616-5270, USA 69 Beach Road, Hampton, VIC 3188, Australia 3 University of California Cooperative Extension, Kern County, 1031 South Mount Vernon Avenue, Bakersfield, California 93307, USA *Corresponding author: Tel: 15596466510, Email: [email protected] 1 2 Background and Aims In the warm regions of central and southern California, areas most suitable for growing table grapes, nematodes, especially root-knot nematodes (Meloidogyne spp.) are the most important soil pests, and their feeding may reduce grapevine yields by as much as 25% (Anwar and McKenry, 2000). Pre-plant soil fumigation has been an important management practice to help control soil pest populations, but the future availability of effective fumigants and post-plant nematicides is uncertain, and some species of root-knot nematode have adapted to the resistance mechanisms of commonly used rootstocks. Therefore, plant breeders have redoubled their efforts to develop new rootstocks with broad and durable pest resistance, and a number of new rootstocks have been released to industry in recent years. ORAL SESSION 4 The aim of this study was to determine the effect that a range of rootstocks, including traditional and recently released stocks, may have on fruit quality and yield, vine nutrition and vigour, and plant-parasitic nematode species diversity and populations levels, in three different commercial table grape vineyards. Experimental Procedures and Results Three rootstock trials were established in commercial vineyards in 2008 and 2009. Autumn King is the scion in two of the vineyards, and Scarlet Royal is the scion in the other vineyard. Eight to 15 rootstocks are being evaluated in each vineyard (Table 1), however, vines on GRN5 were planted at Ducor, but most have died or struggled to establish, so GRN5 has been eliminated from that trial. Vines on each rootstock have been planted in six to nine-vine plots, replicated five times in each vineyard. Petiole samples were collected at bloom from each plot, and macro and micro nutrient content determined. Fruit quality, yield, pruning weights, and nematode populations are monitored annually. Rootstocks strongly influenced mineral nutrient content of ‘Autumn King’ and ‘Scarlet Royal’ petioles at all locations. At Ducor, the ‘Autumn King’ vines on Freedom had greater NO3-N, Mg, and K than own-rooted vines, or vines on most other rootstocks. In contrast, vines on Harmony amassed macro nutrients at a similar, or lower, level as ownrooted vines. Most of the other rootstocks induced similar or higher levels of macronutrients in petioles as ownrooted vines. Petiole nitrate levels of all vines at Ducor were >600ppm, suggesting all vines had adequate nitrogen nutrition. Rootstock effects on micronutrients at Ducor were more variable than their effects on macronutrients. Vines on Freedom had lower levels of Zn and Cu than own-rooted vines, whereas vines on Harmony had similar levels of Zn and Cu as own-rooted vines. As in the case of macro nutrients, the two Vitis vinifera stocks, ‘Crimson’ and ownrooted, were generally more similar to each other than to most other rootstocks. One striking benefit of most rootstocks other than 10-17A was a clear reduction in petiole Na and Cl levels compared to vines on V. vinifera roots. ‘Autumn King’ vines at Traver shared some similar rootstocks as the trial at Ducor, including Freedom, Harmony, 10-17A, RSD-34, Teleki 5C, and own-root, and most of these stocks induced similar effects on vine nutrition at both sites. Once again, vines on Freedom amassed the most, or among the most, NO3-N, Mg, and K, whereas vines on their own roots typically amassed the lowest, or among the lowest, levels of those macronutrients. Vines on Harmony had NO3-N and Mg levels that were similar to those on own-rooted vines, as observed at Ducor, though vines on Harmony at Traver had higher levels of P and K than own-rooted vines, in contrast to what was observed at Ducor. Vines on 10-17A, RSD-34, and Teleki 5C had relatively low NO3-N, Mg, and K at both sites. Rootstock effects on micronutrients were also generally similar to what was observed at Ducor, with vines on Freedom having the lowest levels of Zn and Cu, and most rootstocks except 10-17A and RSD-34 reducing Na and Cl content compared to ownrooted vines. 56 7th International Table Grape Symposium Table 1. Rootstocks tested in ‘Autumn King’ and ‘Scarlet Royal’ table grape vineyards in California. Rootstock Origin Parentage ‘Autumn King’, Ducor, California USDA, Fresno V. vinifera Freedom USDA, Fresno V champinii x 1613C Harmony USDA, Fresno V. champinii x 1613C Teleki 5C Hungary V. berlandieri x V. riparia Salt Creek (Ramsey) Texas V. candicans x. V. rupestris 1103-P Sicily, Italy V. berlandieri x V. rupestris ‘Crimson Seedless’ USDA, Fresno V. vinifera USDA 10-17 A USDA, Fresno V. simpsoni x Edna ((V. lincecumii x V. rupestris) x V. vinifera) RS-3 UC KAC, Parlier (V. candicans x V. rupestris) x (V. riparia x V. rupestris) RSD-34 UC KAC, Parlier ((V. candicans x V. rupestris) x (V. riparia x V. rupestris)) x V. doaniana GRN1 UC Davis V. rupestris x M. rotundifolia hybrid GRN2 UC Davis (V. rufotomentosa x (V. champinii Dog Ridge x Riparia Gloire)) x Riparia Gloire GRN3 UC Davis (V. rufotomentosa x (V. champinii Dog Ridge x Riparia Gloire)) x V. champinii c9038 (probably V. candicans x V. monticola) GRN4 UC Davis (V. rufotomentosa x (V. champinii Dog Ridge x Riparia Gloire)) x V. champinii c9038 (probably V. candicans x V. monticola) GRN-5 UC Davis (V. champinii Ramsey x Riparia Gloire) x V. champinii c9021 (probably V. candicans x V. berlandieri) ORAL SESSION 4 ‘Autumn King’ ‘Autumn King’, Traver, California ‘Autumn King’ USDA, Fresno V. vinifera Freedom USDA, Fresno V champinii x 1613C Harmony USDA, Fresno V champinii x 1613C Salt Creek (Ramsey) Texas V. candicans x. V. rupestris Teleki 5C Hungary V. berlandieri x V. riparia RS-3 KAC, Parlier (V. candicans x V. rupestris) x (V. riparia x V. rupestris) RS-9 KAC, Parlier (V. candicans x V. rupestris) x (V. riparia x V. rupestris) USDA 10-17A USDA, Fresno V. simpsonii x Edna ((V. lincecumii x V. rupestris) x V. vinifera)) RSD-34 KAC, Parlier ((V. candicans x V. rupestris) x (V. riparia x V. rupestris)) x V. doaniana ‘Scarlet Royal’, Goshen, California ‘Scarlet Royal’ USDA, Fresno V. vinifera Freedom USDA, Fresno V champinii x 1613C 1103-P Sicily, Italy V. berlandieri x V. rupestris Kober 5BB Austria V. berlandieri x V. riparia Teleki 5C Hungary V. berlandieri x V. riparia RS-3 KAC, Parlier (V. candicans x V. rupestris) x (V. riparia x V .rupestris) RS-9 KAC, Parlier (V. candicans x V. rupestris) x (V. riparia x V. rupestris) USDA 10-23B USDA, Fresno V. doaniana 10-17A USDA, Fresno V. simpsoni x Edna ((V. lincecumii x V. rupestris) x V. vinifera)) RSD-34 KAC, Parlier ((V. candicans x V. rupestris) x (V. riparia x V. rupestris)) x V. doaniana 7th International Table Grape Symposium 57 ‘Scarlet Royal’ vines at Goshen had considerably lower petiole NO3-N levels than vines in other vineyards. Petioled NO3-N ranged from 490 ppm for Teleki 5C to approximately 890 ppm for Freedom. Vines on Freedom, 1103P, and 10-23B had the highest petiole NO3-N levels, and own-rooted vines had among the lowest NO3-N levels. These findings bolster the observations from the other vineyards where Freedom enhanced petiole NO3 content. Petiole K contents of all vines were fairly similar in this vineyard, though vines on Freedom had the highest K content, as in other vineyards. Once again, own-rooted vines had the highest levels of Na and Cl. Another consistent finding was the fact that vines on Freedom tended to have the lowest, or among the lowest, levels of Zn, a finding that has been reported previously. Vines on 1103P had the highest pruning weights. Autumn King, Ducor. Rootstocks affected berry weight, with vines on Salt Creek, 1103P, and Freedom having the heaviest berries, and own-rooted vines and vines on RSD-34 and GRN1 having the lightest, or among the lightest berries; vines on other stocks generally produced berries of similar mass. Rootstocks also affected fruit composition, with vines on RSD-34, Teleki 5C, and Harmony having higher Brix than vines on 10-17A, GRN1, or Salt Creek. Juice pH and TA was about 4 and 3 (g.L-1), respectively, and not necessarily related to Brix. It appears there was an inverse relationship between petiole K levels and juice pH, as has been observed in wine grapes (Mullins et al., 1992). For example, vines on Freedom, and GRN2, GRN3, GRN4, and RS3 had the highest petiole K levels and among the highest pH levels. Harmony was an exception, having relatively low K, but high pH. The high pH of fruit from vines grafted to Harmony may be more related to high fruit maturity, as evidenced by their high Brix. ORAL SESSION 4 Rootstocks affected the amount of packed fruit and culls on the first pick, and those effects were enough to also affect the total amount of packed fruit. Vines on ‘Crimson’, Freedom, 1103P, 10-17A, GRN3, GRN4, Harmony, RS3, Salt Creek, and Teleki 5C all produced more packable fruit on the first harvest than own-rooted vines, but ultimately only vines on ‘Crimson’, 1103P, GRN3, RS3 and Salt Creek produced more than own-rooted vines for the season as a whole (considering both harvests). The first harvest from these vines was in 2013, and the differences in yield can likely be attributed to vine size. Rootstocks also affected cull weights on the first harvest, with the most productive vines generally having the most culls. Autumn King, Traver. Vines at this vineyard had much greater average berry weights than those at Ducor, and there were few differences in berry weights among treatments. Vines on Ramsey and Teleki 5C had heavier berries than those on RS9 and Freedom, which is in contrast with the findings from Ducor, where vines on Freedom had among the heaviest berries. Berries from vines on RS3 had the highest Brix, whereas vines on 10-17A had among the lowest, a finding that is consistent with the Ducor trial. Vines with the highest petiole K levels, Freedom, RS3, and Harmony, had the highest fruit pH, a relationship that was also observed at Ducor. Unlike Ducor, most rootstocks had no effect on yield at Traver, the vines of which are a few years older. However, vines on 10-17A had much greater yields than vines on any other stock, with most of the fruit being picked on the second harvest. It is uncertain why vines on 10-17A had much greater yields than vines on other stocks; similar results were not observed in previous years. Additional years of data are needed to determine if this finding is repeatable or spurious. Scarlet Royal, Goshen. Scarlet Royal vines had berries of about 9 grams, and berry weight was not affected by rootstock. However, the stocks did slightly affect berry colour and composition. Vines on RS9 had among the darkest (lowest “lightness”), most red coloured (as evidenced by the lowest hue angle) fruit, whereas vines on their own roots or on 10-17A had the most light coloured, least red fruit. Vines on RS9 also had the highest Brix, and the lowest titratable acidity (TA), whereas fruit from own rooted vines had among the lowest Brix and highest TA. There were no differences among rootstocks with respect to packed fruit or culls on the first harvest, but on the second harvest two rootstocks, 10-23 B and RSD-34, were more productive than own rooted vines. However, not much fruit was harvested on the second pick as compared to the first and, overall, rootstocks did not affect total packable yields. Discussion and Significance of the Study Characteristic differences among rootstocks are becoming clear, and these data will help table grape growers select the most appropriate rootstocks for new vineyards. References Anwar SA and McKenry MV. 2000. Penetration, development and reproduction of Meloidogyne arenaria on two new resistant Vitis spp. Nematropica 30: 9-17. Mullins MG, Bouquet A and Williams LE. 1992. Biology of the Grapevine. Cambridge University Press, New York. 58 7th International Table Grape Symposium Oral Presentation Abstracts THURSDAY 13 NOVEMBER 2014 Session 5. Pest and disease management Keynote address Identification and management of trunk diseases in Australia Mark R. Sosnowski* South Australian Research and Development Institute (SARDI), GPO Box 397, Adelaide, South Australia 5001, Australia, Email: [email protected] Background ORAL SESSION 5 Eutypa and botryosphaeria dieback increasingly contribute to grapevine decline in Australia and worldwide, reducing vineyard productivity and longevity. Vines are infected, by species of Diatrypaceae and Botryosphaeriaceae, through pruning wounds and colonise wood, causing dieback and eventual vine death, and in the case of eutypa dieback, stunting and yellowing of shoots and leaves via toxins produced by the Eutypa lata fungus. Worldwide, grapevine industries are under increased pressure from trunk disease due to aging vineyards and production stresses, in particular Australia and New Zealand, which are dominated by the highly susceptible wine grape varieties Shiraz, Cabernet Sauvignon and Sauvignon Blanc, and management of dieback is becoming imperative. Culturally, pruning should be avoided in wet weather if possible and preferably delayed to late winter when wound healing is more rapid, inoculum levels reduced and sap flowing. Removal of dead wood from grapevines and alternative hosts in and around the vineyard will also reduce the potential inoculum level. Contamination of pruning tools is not considered a major means of spreading the disease. Wounds can be protected effectively with the application of paints and pastes such as Greenseal, Gelseal, Bacseal (each containing tebuconazole) and Garrison Rapid (cyproconazole), which are registered and recommended as wound protectants, especially on large wounds. The fungicides carbendazim, tebuconazole, fluazinam and pyraclostrobin are the most effective available in Australia and New Zealand as wound protectants and current research is working towards registration for control of eutypa and botryosphaeria dieback. Fungicides can be applied efficiently to pruning wounds with commercial spray machines. It is important to direct nozzles to target the pruning wound zone and use high spray volumes (600L.ha-1) to maximise coverage on wounds. Biological control agents, such as the fungi Trichoderma spp. have controlled E. lata in trials worldwide, but the results have been variable and control is usually less effective than fungicides, paints and pastes. Vinevax (containing Trichoderma) is registered for eutypa dieback control in Australia and New Zealand. Although biological control offers long-term protection, the time required for biological control agents to colonise the wound creates a window of susceptibility to infection. Garlic and lactoferrin have also shown potential for pruning wound protection. Control of infected vines can be achieved by remedial surgery, the process of cutting out all discoloured cordon or trunk wood by and a further 10cm of healthy wood to ensure all infection is removed. Remaining wounds must be protected, preferably with paints or pastes. Cordons and trunks can be retrained from watershoots to return vines to full production within a few years. Research is ongoing in Australia and New Zealand, with efforts now focussing on inoculum dispersal, wound susceptibility, optimal timing of fungicide application, potential sources of resistance and effects of water stress along with the economic impact of trunk disease and the cost-benefit of managing it. 7th International Table Grape Symposium 59 Canker diseases in the Coachella valley: Incidence and evaluation of management strategies Carmen Gispert1,* and Philippe E Rolshausen2 University of California Cooperative Extension, 81077 Indio Blvd. Suite H, Indio, CA 92201. Department of Botany and Plant Sciences, University of California, Riverside, CA 92521. * Corresponding author: Tel: +1 760 342 2466, Email: [email protected] 1 2 Background and Aims The Coachella Valley represents a unique area for its climatic conditions and offers an attractive niche for the production of table grapes. It produces the earliest grape crop in the country ensuring a favourable market with lucrative prices. Grapevine canker diseases such as Eutypa dieback, Esca, or Bot canker caused by fungal pathogens infect the grapevines through pruning wounds and are one of the primary factors limiting vineyard longevity and productivity. These diseases have been studied mainly in wine grapes and little is known of their impact in table grape production. Our goal was to identify the causal agents of trunk diseases in vineyards grown in the Coachella valley and evaluate if grapevines can be protected from infection early in their development by double pruning (pre-pruning in early winter followed by hand pruning) before bud break, and the application of Topsin M (thiophanate-methyl registered for grapes in California) immediately after pruning. Experimental Procedure Sixty wood samples were collected from cordons and spurs of vineyards in the Coachella valley in southern California. Cankers were collected from spurs, cordons and trunks showing dieback symptoms or wood streaking. Small pieces of wood with canker symptoms were placed on potato dextrose agar. Cultures were incubated at room temperature until fungal colonies were observed. Pathogens were identified to the species based on morphological characters and DNA analysis using multi-gene sequence phylogenies. ORAL SESSION 5 In addition the efficacy of Topsin will be evaluated in the winter of 2014 using artificial inoculations of Lasodiplodia theobromae, Lasodiplodia crassispora, Togninia minima and Phaeomoniella chlamydospora after pruning and the percentage of infected spurs will be recorded (Rolshausen, et al., 2010). Environmental conditions in the Coachella valley are not conducive for trunk diseases as low rainfall occurs during the pruning season (December). However, a common practice is the use of evaporative cooling with overhead irrigation during that time, and is likely that this practice has allowed the fungi to spread and cause disease. Results and Discussion We identified the following fungal species known to be associated with esca/measles and bot canker: Phaeoacremonium parasiticum, Phaeomoniella chlamydospora, Togninia minima, Phaeoacremonium fuscum, Phialophora sp., Neoscytalidium dimidiatum, Lasodiplodia theobromae, Lasodiplodia crassispora, and Eutypella sp. We confirmed the presence of L. theobromae in Coachella (Urbez et al., 2006). We identified T. minima and P. chlamydopsora, two of the major pathogens associated with Esca. In addition N. dimidiatum was found for the first time on grapevines in California. Symptomatic grapevines infected with N. dimidiatum showed shoot blight with wilting and necrosis of leaves and shrivelled berries. Some vines had collapsed completely. Wood cankers in the spurs, cordons and trunks in the affected vines were also present (Rolshausen et al., 2013). In the Coachella valley, grapevines are often replanted between stumps left from previous plantings. Is very likely that this practice contributes to increasing disease incidence because stumps are reservoirs for fungal inoculum and spores are spread when overhead irrigation is used. A long term goal of this study is to test if the combination of double pruning and tractor sprays of Topsin M immediately after pruning can reduce infection. We are currently investigating the long-term of this management strategy in young vineyards in the Coachella valley. 60 7th International Table Grape Symposium Acknowledgments Funding Source was provided by the California Table Grape Administrative Committee. 82901 Bliss Avenue, Indio, CA. 92201. References Rolshausen PE, Úrbez-Torres JR, Rooney-Latham S, Eskalen A, and Gubler WD. 2010. Evaluation of pruning wound susceptibility and protection against fungi associated with grapevine trunk diseases. American Journal of Enology and Viticulture 61: 113-119. Rolshausen PE, Akgül D, Perez R, Eskalen A and Gispert C. 2013. First report of wood canker caused by Neoscytalidium dimidiatum on grapevine in California. First Look Plant Disease. PDIS-04-13-0451-PDN. Úrbez-Torres JR, Leavitt GM, Voegel TM and Gubler WD. 2006. Identification and distribution of Botryosphaeria spp. associated with grapevine cankers in California. Plant Disease 90: 1490-1503. ORAL SESSION 5 7th International Table Grape Symposium 61 Control of grapevine powdery mildew with the natural biofungicide Timorex Gold M Reuveni1,2,*, JC Arroyo2 and JL Henriquez3 Golan Research Institute, University of Haifa, Katzrin 12900 Israel Stockton Israel Ltd, 17 Ha’Mefalsim St. P.O.B. 3517 Petach Tikva 4951447, Israel 3 Fac. Cs. Agronómicas, Universidad De Chile, Santa Rosa 11.315, Casilla 1004, La Pintana, Santiago Chile *Corresponding author: Email: [email protected] 1 2 Background and Aims Powdery mildew (Erysiphe necator) is the main disease in table grape production in dry and warm areas in Chile and Peru as well as in many other countries that grow table grapes. Often it is a problem from bud break up to harvest. An average of 16 to 18 applications per season are used for the control of this disease due the predominantly favourable environmental conditions for powdery mildew development. Considering the amount of treatments for powdery mildew control in a season and the continued use (more than 3 times in the season) of fungicides with similar modes of action (MoA) and considering also that table grapes growers need to comply with residue levels (not to exceed MRLs) or a certain number of active ingredient residues, these issues limit the alternation of fungicides with different MoA, giving as a result loss of sensibility in most of the fungicides for the control of powdery mildew. With this scenario, the introduction of new effective fungicides with a different and unique mode of action, with very low risk for resistance development and without adding residues seems to be very promising addition to disease management programs that allow table grapes growers to produce high quality grapes with lower amount of residues and keeping the effectiveness of the fungicides with specific MoA in a high level. Experimental Procedures and Results ORAL SESSION 5 The natural biofungicide Timorex Gold (TG) contains 23.8% of Melaleuca alternifolia extract with a unique MoA (FRAC, F7) was found to be effective against broad spectrum of plant pathogenic fungi and was evaluated in table and wine grapes against powdery mildew (PM). Applications of TG at 1.0, 1.5 and 2.0L.ha-1 as prophylactic and curative treatment effectively controlled powdery mildew and suppressed the existed colonies of Erysiphe necator. Spraying at the rate of 2.0L.ha-1 provided an excellent curative control in infected tissue. In-vitro trials demonstrated that TG with very low concentrations can inhibit the conidial germination of Erysiphe necator >95 % from 0.01ppm (Table 1) Confirming the efficacy performance demonstrated on the field in different countries with diverse environmental conditions. Table 1. Percentage of germination of conidia of Erysphe necator, growing in Timorex Gold (23% Melaleuca alternifolia extract) amended media, and percentage of inhibition of germination. Chile 2011. Concentration ppm Conidial Germination (%) Inhibition (%) Control 30.00 - 0.0001 16.50 45.0 0.001 14.83 50.6 0.01 1.5 95.0 0.1 0.25 99.2 Field trials were conducted during 2010-11, 2011-2012 in Chile and in 2012-2013, 2013-2014 in Peru and other countries. These experimental trials were performed in table and wine grapes on different cultivars in Chile such as Moscatel, Ovalle, Coquimbo (Table 2), Cabernet Sauvignon, Antumapu, Santiago (Table 3) and Red Globe Villacuri, Ica, Peru (Tables 4 and 5). Chile trials were designed as complete randomized design with 6 treatments and 4 replications, 3 consecutive applications with spray volume of 800L.ha-1 at 7-10 days interval. Peru trial designed as complete randomised block design with 5 treatments and 4 replications, 1 application with a spray volume of 600L.ha-1. Disease incidence (percentage of infested cluster per treatment) and severity (percentage of infested berries per plant) was recorded in these trials. In all assessments infested clusters and berries were considered for evaluations and recorded as percentage of incidence and percentage of severity. In Chile trials applications were performed 62 7th International Table Grape Symposium from fruit set up to véraison. Incidence and severity were evaluated just before the first application and then at 7, 14, days after last spray, respectively. In Peru trials applications were performed at berries of 6-8mm and bunch close respectively in each trial. Incidence and severity were evaluated just before the first application and at 4, 7, and 10 days after the single spray. Table 2. Incidence (percentage of infested clusters per plant), severity (percentage of infested berries per cluster) and % of Control observed in table grapes cv. Moscatel de Alejandría at full colour berries after 7 days of last application. Ovalle. Coquimbo, Chile 2011-2012. Treatments Incidence (%) Severity (%) Control (%) 22.3 bc 3.20 bc 88.7 17.1 cd 1.60 c 92.2 Difenoconazole 25% 150mL.ha 7.9 d 0.50 d 97.0 Myclobuthanil 20% 120mL.ha 27.1 ab 8.00 ab 84.4 Sulphur Flo 3.0kg.ha 22.9 bc 3.60 bc 89.2 Untreated Control 89.3 a 17.6 a Timorex 1.0L.ha -1 Timorex Gold 1.4L.ha -1 -1 -1 -1 X X Means follow by same letter are not different according Tukey (α < 0,05). Table 3. Incidence (percentage of infested clusters per plant), severity (percentage of infested berries per cluster) and % of control observed in wine grapes cv. Cabernet Sauvignon at full colour berries after 14 days after last application. Antumapu, Santiago, Chile, 2010-2011. Treatments Incidence (%) Severity (%) Control (%) 40 b 2.95 b 96.4 40 b 1.05 b 98.7 50 b 3.50 b 95.8 Myclobuthanil 20% 120mL.ha 30 b 0.50 b 99.4 1.Sulphur Flo 3.0kg.ha 2.Triadimenol 200g.ha-1 3.Sulphur Flo 3.0kg.ha-1 100 b 78.58 a 4.9 Untreated Control 100 b Timorex 1.0L.ha -1 Timorex Gold 1.5L.ha -1 Timorex Gold 2.0L.ha -1 -1 X -1 ORAL SESSION 5 X 82.60 a Means follow by same letter are not different according Tukey (α < 0,05). Table 4. Incidence (percentage of infested clusters per plant), severity (percentage of infested berries per cluster) and % of control observed in table grapes cv. Red Globe at berries 12mm. Villacuri, Ica, Peru, 2012. Treatments Incidence (%) Severity (%) Control (%) Timorex Gold 1.0L.ha-1 62.5 b 2.29 b 89.9 Timorex Gold 1.5L.ha-1 62.5 b 1.04 b 91.9 60.4 b 0.73 b 94.3 64.6 b 1.00 b 92.2 100.0 a 12.79 a Timorex Gold 2.0L.ha -1 Tebuconazol 25% 750g.ha Untreated Control X -1 Means follow by same letter are not different according Tukey (α < 0,05). Table 5. Incidence (percentage of infested clusters per plant), severity (percentage of infested berries per cluster) and % of control observed in table grapes cv. Red Globe at full colour berries. Villacuri, Ica, Peru, 2013. Treatments Incidence (%) Severity (%) Control (%) Timorex Gold 1.0L.ha 35.0 b 0.55 b 78.9 Timorex Gold 1.2L.ha 17.5 bc 0.18 b 93.1 Timorex Gold 1.5L.ha 15.0 bc 0.15 b 94.3 Timorex Gold 2.0L.ha-1 10.0 c 0.10 b 96.2 Untreated Control 60.0 a 2.61 a -1 -1 -1 X Means follow by same letter and not different according Tukey (α < 0,05). 7th International Table Grape Symposium 63 Trials in Chile revealed that spraying TG at application rate of 1.5-2.0L.ha-1controlled PM on berries, and was as effective as sulfur and systemic fungicides against powdery mildew when applied at 10 day intervals. Nevertheless spraying TG at rate of 1.0L.ha-1 shows an effective prophylactic effect against PM in berries, when applied at 7 days intervals. In the Chile trials, all TG dosages show significant difference compare to the untreated control 7 and 14 days after three consecutive sprays with a level of efficacy above 85% at 7 days after the last application of each trial, considering that the trial started with powdery mildew symptoms. TG was also as effective as sulfur and DMI’s fungicides in controlling PM on berries. Peru trials show strong effectiveness of TG in rates of 1.0, 1.5 and 2.0L.ha-1 up to 7 days starting with medium and high incidence of powdery mildew before spray one time at two different phonological stages. The first trial was performed in critical phonological stage with high disease pressure and favourable disease development conditions and TG demonstrated to be highly effective with > 89 % of control. The second trial was performed with mediumhigh incidence in late season. In this case all TG treatments recorded very low severity < 0.6% , in a stage where treatments should have strong curative effect to reduce late powdery mildew and avoid worst sanitary conditions of the grapes berries, but at the same exist some limitations in the use of fungicides at that stage due residues concern. TG as a natural bio fungicide does not harm beneficial insects and bees, has no residue limitations (Is exempt of MRL’s) and may complement sulfur, biological and synthetic fungicides in table grape production, as well as, being an attractive tool for anti-resistance programs. ORAL SESSION 5 64 7th International Table Grape Symposium Effective control of fruit fly for market access using a systems management approach in table grapes David R Oag1,*, Brendan P Missenden2 and Edward L Hamacek2 Horticulture and Forestry Science, Department of Agriculture Fisheries and Forestry, Applethorpe, Queensland, 4380, Australia 2 Ecosciences Precinct, Brisbane, 4000 *Corresponding author: Tel: +61 7 4681 6147, Email: [email protected] 1 Background and Aims Queensland fruit fly (Qfly) (Bacterocera tryoni) is naturally occurring throughout Queensland and occurs in large numbers in hot, humid conditions of eastern Australia (Drew, 1989). Qfly numbers are small in the table grape production districts located in inland Queensland where conditions are much drier. In 2008, access restrictions were introduced in several state domestic markets for Queensland table grapes. At the same time the insecticides (fenthion and dimethoate) most commonly used for control of Qfly were being withdrawn from use in Australia. This necessitated the development of a protocol for the control of Qfly, so Queensland table grapes could maintain access to these important domestic markets. The strategy taken was a systems management approach involving pre-harvest bait sprays along with culling damaged fruit and inspection during the harvesting process. The protocol for table grapes (ICA20) is based on the protocol developed for citrus (ICA28). Systems management approaches are internationally accepted for the control of various pests, including fruit flies, with increasingly more protocols being accepted to access international export markets (ISPM 35, 2012). A two year field study was undertaken to confirm the effectiveness of the systems management approach to control Qfly in table grapes. Experimental Procedure and Results ORAL SESSION 5 Field trials were established in vineyards of Menindee Seedless and Red Globe in each of the three major Queensland table grape districts (Emerald, Mundubbera, St George), each comprising a one hectare plot and total of six trials per variety. A regime of bait sprays was applied throughout the season to control Qfly. Bait spray applications commenced in the crop at least 6 weeks prior to harvest and continued at 4-10 day intervals. The bait (Mauris Pinnacle Protein Lure [protein hydrolysate], and Hy-mal® [1150g.L-1 maldison]) was applied at 20L.ha-1 to the grapevine foliage high in the canopy and above the fruit zone, as a continuous strip to every 3rd row. Qfly numbers were monitored using traps installed at each trial site. Each season, 9,000 bunches per variety were collected for assessment of Qfly infestation. This consisted of 3,000 bunches collected immediately prior to commercial harvest in order to quantify the level of control achieved from bait sprays alone. A further 6,000 commercially packed bunches were also collected for assessment, which included the additional measure of culling and inspection. The individual bunches were incubated at 26°C and 70% humidity for 7-10 days to allow development of fruit fly larvae that may be present in fruit. Fruit fly trapping numbers were very low over both seasons and rarely exceeded 1 fly per trap per day. The maximum number of flies ever caught was 3 flies per trap per day on one occasion (Figure 1). There was no apparent difference between the three districts for fruit fly population pressure. The level of infestation was not significantly different between varieties. In the first season (2008/09), low numbers of infested fruit was recorded from most vineyards for both varieties. The level of infested fruit was considerably greater at one vineyard in Emerald (Table 1) and it was subsequently established that the localised infestation within the crop was attributable to an incursion of flies from untreated fruit trees located nearby. In the following season, no infested berries were found from all locations, in both varieties, including the vineyard where a high infestation was recorded in the previous year. Discussion and Significance of the Study A systems management strategy incorporating bait sprays with harvest culling and inspection provides effective control of Qfly in table grapes grown in subtropical regions of Queensland. The systematic application of the bait (every 3rd row in a continuous strip) provides a blanket coverage of the vineyard in a similar sense as an insecticide spray. 7th International Table Grape Symposium 65 A greater level of control was achieved in the second season and this was likely due to the growers becoming more experienced in applying and managing the timing of bait sprays. A systems management strategy demands more vigilance by growers than the past practice of cover sprays using broad spectrum organophosphate insecticides. Baits applied well above ground attract the greatest number of flies. Lloyd et al. (2005) demonstrated very few flies visited baits applied close to the ground (0.3m), however baits applied at heights of 1.0m or 1.8m were significantly more effective at attracting flies as evidenced by 15-times and 25-times more flies killed, respectively. Similar studies on Qfly (Balagawi, 2012) concur that bait sprays applied high in the canopy results in more flies feeding. Baits applied to foliage are more attractive to flies. Maximum fly visits are achieved where bait sprays are applied to crop foliage (Lloyd, 2005). Applying baits to non-foliar materials (eg trellis posts) is an option where the crop is highly sensitive to bait phytotoxicity, however the practical difficulty of applying the bait spray increases the risk of not achieving effective fruit fly control. Reducing fly population pressure from ‘hot spots’ outside the vineyard assists in achieving effective control of Qfly. Treating other fruit fly host plants in the vicinity of the vineyard is an integral part of a systems management strategy and a requirement within ICA-20. Extending this concept to area-wide management, where bait spraying in nearby townships is conducted to control sources of fruit flies, has been successful in citrus growing districts in Queensland (Lloyd et al., 2010). Initially developed for table grape growers in Queensland, the systems management strategy and ICA20 has now benefited growers in the Sunraysia (Victoria) where outbreaks of Qfly have occurred in recent years. The relevance of the systems management strategy for providing effective control of fruit fly may increase in the event of climate change leading to more frequent outbreaks in southern Australia. In the domestic markets with restrictions on access of Queensland table grapes there has been zero detections of fruit fly in packed table grapes by quarantine authorities since the adoption of ICA20 by Queensland growers. This reinforces the effectiveness of the systems management strategy. ORAL SESSION 5 Table 1. Infested fruit and calculated percent infestation rate of Menindee Seedless bunches for pre-harvest (pick) sample and packed fruit sample in season 2008/09. District /Vineyard No. infested bunches No. infested berries % Bunches infested Upper % bunch infestation (95% confidence) Emerald 3 Pick 507 22 34 4.34 6.196075 Pack 1273 13 15 1.02 1.623574 Emerald 2 Pick 482 0 0 0.00 0.621515 Pack 1302 0 0 0.00 0.230084 Combined 1784 0 0 0.00 0.167920 Mundubbera 2 Pick 711 0 0 0.00 0.421336 Pack 1178 0 0 0.00 0.254304 Mundubbera 1 Pick 512 0 0 0.00 0.585098 Pack 1250 0 0 0.00 0.239656 Total pick 1223 0 0 0.00 0.244947 Total pack 2428 0 0 0.00 0.123381 Combined 3651 0 0 0.00 0.082051 Pick 1035 1 1 0.10 0.458271 Pack 2306 0 0 0.00 0.129909 Combined 3341 1 1 0.03 0.141966 St George 66 Sample type No. Bunches 7th International Table Grape Symposium 3.5 3.0 Mean Qfly / trap / day 2.5 Emerald 1 Emerald 2 2.0 Mundubbera 1 1.5 Mundubbera 2 1.0 St George 2 St George 1 0.5 22/08/2009 29/08/2009 5/09/2009 12/09/2009 19/09/2009 26/09/2009 3/10/2009 10/10/2009 17/10/2009 24/10/2009 31/10/2009 7/11/2009 14/11/2009 21/11/2009 28/11/2009 5/12/2009 12/12/2009 19/12/2009 26/12/2009 2/01/2010 9/01/2010 16/01/2010 23/01/2010 30/01/2010 6/02/2010 13/02/2010 0.0 Figure 1. Mean number of Queensland fruit flies (Bactrocera tryoni) per trap per day recorded at trial sites in season 2009/10. Acknowledgements ORAL SESSION 5 We thank Marianne Eelkema, Allan McWaters and Thelma Peek for their dedicated technical assistance. The collaboration of individual Queensland table grape growers who hosted the vineyard trials is gratefully acknowledged. The research was financially supported by a voluntary contribution from grower members of GrapeConnect, with matching funds from the Australian Government. References Bagalawi S, Jackson K, Hamacek EL and Clarke AR. 2012 Spatial and temporal foraging patterns of Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), for protein and implications for management. Australian Journal of Entomology 51: 279-288 Drew, R. A. I. (1989). The tropical fruit flies (Diptera: Tephritidae: Dacinae) of the Australasian and Oceanian regions. ICA-20: Pre-harvest treatment and inspection of table grapes. http://domesticquarantine.org.au/ica-database/ queensland/queensland-ica-20 Lloyd AC, Hamacek EL, Kopittke RA, Neale CJ and Peek T. 2005. Development of non-foliar bait spot treatments for fruit fly control. Final project report, HG02066. Horticulture Australia Ltd. Lloyd AC, Hamacek EL, Kopittke RA, Peek T, Wyatt PM, Neale CJ, Eelkema M and Gu HN. 2010. Area-wide management of fruit flies (Diptera: Tephritidae) in the Central Burnett district of Queensland, Australia. Crop Protection 29(5): 462-469. ISPM 35. 2012. Systems approach for pest risk management of fruit flies (Tephritidae). Rome, IPPC, FAO. http://www.fao. org/docrep/016/k6768e/k6768e.pdf 7th International Table Grape Symposium 67 Session 6. Plant growth regulators Understanding the control of grape berry ripening and developing opportunities for its manipulation C Davies*, C Böttcher and P Boss CSIRO Plant Industry, Adelaide, Australia *Corresponding author: Email: [email protected], Tel: +61 8 83038628 Background and Aims Plant growth regulators (PGRs) are molecules that control global changes in gene expression in plants. These coordinated changes in gene expression play crucial roles in the control of plant development. Plants contain a range of PGRs which have different structures and which are involved in the control of different developmental processes and the plant’s responses to environmental influences. PGRs act through a complex process of recognition and signal transduction to effect these changes. Fruit ripening is a complex process which is largely regulated by PGRs. Classically fruit have been divided by physiologists into two categories. So-called climacteric fruit undergo an increase in respiration and the evolution of ethylene, a gaseous PGR, at the commencement of ripening. The application of ethylene before the commencement of ripening can induce ripening in these fruit (e.g. apples, bananas and tomatoes). In contrast, the ripening of nonclimacteric fruit (e.g. grapes, olives, strawberries) is less dependent on ethylene and appears to be controlled by several other PGRs. However, this doesn’t mean that ethylene doesn’t have some effect on berry ripening and this will be discussed. There are a number of synthetic PGRs, some of which are copies of the endogenous forms, others affect the action of endogenous PGRs or their receptors. The use of gibberellic acid by the table grape industry to control berry size is an example of the utility of PGRs in manipulating fruit development. In this work the role endogenous PGRs play in the control of berry ripening is investigated at both macro and molecular levels. The second aim is to apply this knowledge to manipulate grape berry development, and in particular ripening, for the benefit of the grape and wine industries. Experimental Procedure and Results ORAL SESSION 6 Two basic approaches were used in this research. The first approach was to understand how endogenous PGRs act during berry development. This involved using a range of techniques to study PGR metabolism, perception and signalling at a number of levels. The identity and concentrations of endogenous PGRs were determined throughout berry development using techniques such as stable isotope dilution analysis by LC-MS. Measuring the expression of genes involved in PGR biosynthesis, perception, signalling and breakdown/sequestration also gave valuable information. These investigations were performed using a range of methods including microarray analysis, next generation sequencing and real-time QPCR analysis. Such techniques can also indicate which processes are controlled by each of the PGRs present. This is important in understanding the role of the PGRs during berry development and enables the prediction of effects arising from the perturbation of the action of a particular PGR. Data such as berry weight, total soluble solids, organic acid levels, anthocyanin levels were collected so that PGR levels and associated changes in gene expression could be related to berry developmental stage. Ultimately the PGR-induced changes in gene expression are reflected in changes in the levels of proteins, frequently enzymes, which translate the signalling by PGRs into action within the plant. A number of different methods were used to study these changes including biochemical assays of enzyme activity. Another way to better our understanding the action of PGRs is to apply exogenous PGRs to berries at particular stages of development. A range of natural and synthetic PGRs are available for this purpose. Not only does the application of these reagents indicate how the PGRs work but it also provides tools to manipulate ripening that may be of benefit to industry. PGR treatments were applied at low concentrations by spraying in the presence of a surfactant. These experiments were carried out in randomised, controlled, fully replicated trials on mature vines but ex planta studies on isolated berries were also conducted. The various measures of berry development described above were determined throughout the experiments to follow the effect of the treatment on berry development. Samples were taken throughout these studies for later additional analysis. A range of detailed measurements were taken of PGR levels and changes in gene expression. In many cases wine was made from the fruit and the levels of aroma/flavour molecules in the wine headspace was measured by GC-MS analysis. Sensory analysis with trained panels was also undertaken to determine differences in overall flavour/aroma and wine appearance. 68 7th International Table Grape Symposium These studies showed that some PGRs are involved in the promotion of véraison, and therefore harvest, and others act to delay it. The application of abscisic acid and castasterone, for example, during the pre-véraison phase promotes the onset of grape berry ripening as measured by sugar and colour accumulation and berry weight increase (Symons et al., 2006; Wheeler et al., 2009). Advancing the time of véraison could be useful in growing areas with short seasons, for example, wine grapes in cool areas and table grapes in tropical regions. Other PGRs, in particular auxins, delayed ripening when applied during the pre-véraison period. For example, application of the synthetic auxin 1-naphthaleneacetic acid delayed changes in ripening indicators such as sugar accumulation, skin colouration and acid catabolism (Böttcher et al., 2011, 2013). Interestingly, these treatments also increased the synchronicity of ripening and can affect the accumulation of some wine volatile components. Berry flavour characteristics haven’t been tested directly but small differences in wine flavour and volatiles indicate that there may be some effects on the levels of berry metabolites and therefore berry flavour. At this stage it is not known whether the changes are due to direct effects of the PGR or due to the changes in ripening conditions due to altered timing of véraison. Endogenous PGR levels are governed by their synthesis and their breakdown or sequestration. A family of enzymes called IAA-amido synthetases are important in controlling auxin levels as they sequester indole-3-acetic acid (IAA) into inactive forms through conjugation to amino acids. Investigation of their activity explains why some auxins are more effective than others in delaying berry ripening. Ethylene, the PGR so heavily involved in the ripening of climacteric fruit has a biphasic effect on grape berry ripening, i.e. if applied early in berry development it delayed ripening but if applied nearer to the time of the initiation of ripening it advanced it. The delaying of ripening by ethylene may be due to its interactions with the auxin pathway. This emphasises two important points in regard to PGRs in berries. First, the timing of application of exogenous PGRs is crucial to the effect achieved as the berry response varies during development. Second, the various PGR pathways interact in a complex cross-talk network. Discussion and Significance of the Study Endogenous PGRs play important roles in the control of berry development and a greater knowledge of their action is crucial to understanding processes such as ripening. These studies provide significant insights into the role of PGRs during grape berry development. This information opens the way for the innovative use of a range of PGRs to manipulate berry development for the benefit of the grape and wine industries. For the wine industry exogenous PGRs provide potential tools with which to manipulate the timing of harvest and could be used to overcome a variety of problems associated with the increased season compression and higher temperatures during ripening caused by changing climatic conditions. In some cases delaying ripening and therefore harvest may also be useful to the table grape industry through extending the harvest season. In areas where climatic conditions require more rapid ripening of fruit to avoid cold temperatures or heavy rainfall that could damage fruit advancing ripening would be an advantage. As our knowledge increases further opportunities will arise to manipulate other aspects of grape berry development. ORAL SESSION 6 Acknowledgements We would like to thank Crista Burbidge, Katie Harvey, and Angela Keulen for technical assistance. We also thank Chalk Hill Wines and Nepenthe Wines for providing the fruit used in this study. This work was supported by CSIRO and the Grape and Wine Research and Development Corporation (Grant No CSP0905). CSIRO Plant Industry is a partner of the Wine Innovation Cluster. References Böttcher C, Harvey KE, Boss PK and Davies C. 2013. Ripening of grape berries can be advanced or delayed by reagents that either reduce or increase ethylene levels. Functional Plant Biology. doi: 10.1071/FP12347 Böttcher C, Harvey K, Forde CG, Boss PK and Davies C. 2011. Auxin treatment of pre-véraison grape (Vitis vinifera L.) berries both delays ripening and increases the synchronicity of sugar accumulation. Australian Journal of Grape and Wine Research 17: 1-8. Symons GM, Davies C, Shavrukov Y, Dry IB, Reid JB and Thomas MR. 2006. Grapes on Steroids. Brassinosteroids Are Involved in Grape Berry Ripening. Plant Physiology 140: 150-158. Wheeler S, Loveys B, Ford C and Davies C. 2009. The relationship between the expression of ABA biosynthesis genes, accumulation of ABA and the promotion of Vitis vinifera L. berry ripening by ABA. Australian Journal of Grape and Wine Research 15: 195-204. 7th International Table Grape Symposium 69 Effect of shade and gibberellic acid (GA3) on fruit set and final quality of Thompson Seedless and Crimson Seedless table grape cultivars - A field assay in South Portugal Sara Domingos1,2*, Hugo Nóbrega1, Vânia Cardoso2, José C. Ramalho3, António E. Leitão2, Cristina M. Oliveira1 and Luis F. Goulao2 CEER, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal Agri4Safe/ BioTrop: Polo Mendes Ferrão, Instituto de Investigação Científica Tropical, I.P. (IICT), Pavilhão de Agro-Indústrias e Agronomia Tropical, Tapada da Ajuda, 1349-017 Lisboa, Portugal 3 PlantStress&Biodiversity / BioTrop, Instituto Investigação Científica Tropical, I.P. (IICT), Quinta do Marquês, Avenida da República, 2784-505 Oeiras, Portugal *Corresponding author: Tel: +351213653453, Email: [email protected] 1 2 Background and Aims Thinning berries is an important cultural operation in table grape production, in order to eliminate the excessive number of berries, maximising the quality and value of the production. The reduction of total berry number and removal of small-sized berries results in improved final bunch aspect (decreasing bunch compactness, increasing berries weight and size and uniformising the maturation within the bunch), quality (sugar and colour pigments accumulation) and decreased incidence of diseases(Di Lorenzo et al., 2011). The most common thinning practice is chemical thinning (Gibberellic acid (GA3) sprays) followed by hand adjustments when necessary. However, the success of GA3 treatment depends on the environmental conditions, the concentration and time of application varies with the cultivar, and its use is not authorised in organic production and, in some countries, in integrated crop management system. The effect of shade imposition in berry set was firstly investigated by Roubelakis and Kliewer (1976), reducing 72% and 82% the incident light in Vitis vinifera cv.Carignane vines during five weeks, starting one week before bloom, which resulted in a decreased number of berries per cluster. More recently, it was verified that carbon shortage caused by defoliation and by shade conditions during bloom reduced berry set and the final number of berries per bunch in Semeillon (Lohitnavy et al., 2010) and in ‘Seyval’ and ‘Chambourcin’ (Ferree et al., 2001), respectively. In contrast, no significant differences were found in ‘DeChaunac’ and ‘Vidal’ (Ferree et al., 2001). In table grapes, the response of shade in berries thinning on ‘Black Magic’ was successful tested in greenhouse conditions (Domingos et al., 2013), needing confirmation of this effect under field conditions. ORAL SESSION 6 The aim of this study was to test the potential of total light reduction (with shading nets) and GA3 application during bloom in Thompson Seedless and Crimson Seedless table grape cultivars as thinning methods to reduce berry set and to improve quality. Experimental Procedure and Results The present work was conducted in a commercial vineyard, in the south of Portugal (38° 05’ 23,80” N; 8° 04’ 52,7 1” W) in 2013, with seven-year-old ‘Thompson Seedless’ and ‘Crimson Seedless’ (V. vinifera L.) vines grafted on ‘140 Ruggeri’ rootstock, spaced 3x3m and grown on a overhead trellis system covered with plastic. Five different treatments were tested, in five vines per treatment. For ‘Thompson’ the treatments were: total shade (two polypropylene 82% shading net, Hubel) imposed at 50% (SH_50B) and at 100% (SH_100B) bloom (stage 65 and 69 of the BBCH scale) during 14 and 11 days, respectively and GA3 (Berelex,Kenogard) sprays at 10ppm+12.5ppm+12.5ppm (GA3_35ppm) and 20ppm+25ppm+25ppm (GA3_70ppm) done at 20%, 50% and 100% bloom, respectively. For ‘Crimson’ the treatments were: total shade imposed at 50% (SH_50B) and at 100% (SH_100B) bloom during 18 and 15 days, respectively, GA3 sprays at 1ppm (GA3_1ppm) and 4ppm (GA3_4ppm) at 100% bloom. For both cultivars the controls were non-treated vines. Flower drop was monitored using non-woven cloth bags positioned around 10 bunches per treatment at 100% bloom. Climate conditions were monitored above the canopy of shaded and control vines (WatchDogMicroSta., Spectrum Tech., USA). Leaf gas exchanges (open infrared gas analyser system (CIRAS-1, PP Systems, USA), estimated leaf chlorophyll content (SPAD-502 m, Minolta, Japan) and primary leaf area (non-destructive method according to Lopes and Pinto, 2005), were measured. Final quality and yield were assessed at harvest regarding to bunch weight, total number of berries, rachis length, berry diameter and weight, firmness (by compression test), soluble solid content (SSC), titratable acidity (TA), total phenolic, anthocyanins, resveratrol and catechin skin contents. The bunch 70 7th International Table Grape Symposium compactness (number of berries/cm of rachis) was also calculated. To access the significance of the differences between treatments, one-way ANOVA and Tukey HSD test were performed using Statistix9 software. In 2013, 50% and 100% bloom in ‘Thompson’ occurred at 2nd and 6th May, and in ‘Crimson’ at 10th and 13th May. The day/night mean temperatures were 27/14°C and 25/13°C during the shading periods of Thompson and Crimson Seedless, respectively, and shading nets intercepted 100% of PAR in shaded vines comparing to non shaded ones. In ‘Thompson’, SH_50B, SH_100B and GA3 (35ppm) treatments induced flower drop that reached values of 955±94, 816±75 and 887±74 flowers, respectively, which are significantly higher comparing to natural drop (569±81 flowers), whileGA3 (70ppm) was not significantly different from the control. In contrast, in ‘Crimson’ none of the treatments were effective in promoting significant flower shedding (Table 1). During the shade period, net photosynthetic rate (Pn) was 100% reduced, and stomatal conductance (gs) and transpiration rates were 85-90% reduced, in both varieties, in shaded vines. ‘Crimson’ vines treated with GA3 (4ppm) presented a reduction of ca. 30% in Pn and gs in both time points (during and after shading period) (Figure 1). In control vines of ‘Thompson’ and ‘Crimson’ the primary leaf area at 100% bloom was 23.1±3.0 and 31.6±4.0m2.vine-1, initial shoot length was 151±14 and 141±10 and shoot growth was 2.9±0.3 and 0.7±0.1cm.day-1, respectively. In ‘Thompson’ daily leaf area growth was reduced in shade treatments. Estimated chlorophyll content was significantly reduced in SH_50B comparing to control, from 5 or 21 days onwards shade imposition in ‘Thompson’ and ‘Crimson’, respectively (data not shown). At harvest on ‘Thompson’, shade and GA3 treatments reduced bunch compactness and berry number and increased berry firmness and longitudinal diameter, comparing to control. Both shade treatments decreased bunch weight, SH_50B reduced rachis length while GA3 (35ppm) increased TA. On ‘Crimson’, SH_50B induced a reduction of berries number and bunch compactness and SH_100B reduced berry longitudinal diameter. GA3 (1ppm) reduced SSC and anthocyanins skin content (data not shown) and increased TA and firmness. Resveratrol and catechin contents were unaffected. Discussion and Significance of the Study Only for ‘Thompson Seedless’, shade and GA3 application during bloom significantly reduced fruit set. The shade treatments showed the highest effectiveness on reducing the number of berries per bunch, and affect more significantly vegetative-related parameters. This result is in agreement with the hypothesis that C-starvation during bloom is a major factor in berries abscission induction. ORAL SESSION 6 In ‘Thompson Seedless’ a smaller leaf area (source capability) and an higher daily shoot growth (vegetative sink strength) was observed at bloom, comparing to ‘Crimson Seedless’, which can indicate a greater competition between shoots and berries for photosynthetic resources, making this cultivar more sensitive to thinning treatments. GA3 bloom application is commonly used in table grapes as a means for inducing cluster loosening, however the environment is known to play a key role in the response to growth regulator treatments. The same cultivar can show different results over the years, as observed for ‘Sovereign Coronation‘ in a three-year trial (Reynolds et al., 2006). In ‘Thompson Seedless’, the lower GA3 concentration successfully increased the flowers and berries drop, in contrast with higher doses, which agrees with similar reports for ‘Crimson Seedless’ (Dokoozlian and Peacook, 2001). Still, under our conditions, GA3 didn’t induce flowers and berries drop in ‘Crimson Seedless’ in 2013, further supporting this response dependence of the genotype/environment. Total light reduction drastically decreased the number of berries per bunch in ‘Thompson Seedless’ becoming important to test the effect of less percentage of light reduction on fruit set and final quality. In ‘Crimson Seedless’, a tendency for an increase on % flower drop induced by SH_50B treatment, resulted in a significant decrease of berries number and bunch compactness at harvest. Our results showed that shade can be an alternative thinning method, with effects in both cultivars, although the effect is stronger in ‘Thompson Seedless’. In summary, the magnitude of the shade imposition and the GA3 application effects during bloom depends on the cultivar, time of shade imposition and on the GA3 concentration. To fully evaluate the potential of the shade as a non-chemical commercial method for thinning berries, further studies in different years and with lower % of PAR interception for ‘Thompson Seedless’, and evaluation of economic feasibility, are needed. 7th International Table Grape Symposium 71 Figure 1. Effect of shade and GA3 treatments on the net photosynthetic rate (Pn) and stomatal conductance (gs) for ‘Thompson’ and ‘Crimson Seedless’. Different letters means that treatments were significantly different (P ≤ 0.05), uppercase and lowercase for comparison during and after shade, respectively. ORAL SESSION 6 Table1. Effect of shade and GA3 treatments on percentage of flower drop and on shoot and primary leaf area (LA) growth rates during shade period and bunch and berry quality at harvest, on ‘Thompson Seedless’ vines (mean±SE). Different letters (a,b,c) express significant differences between treatments (P ≤ 0.05). Thompson Seedless Control GA3 (35ppm) GA3 (70ppm) SH_50B SH_100B 63.1±4.2 c 83.0±1.9 b 73.7±4.0 bc 99.0±0.7 a 98.0±1 a Shoot growth rate (cm.day-1) n=5 2.9±0.3 ab 3.8±0.4 a 4.1±0.2 a 1.6±0.4 b 1.9±0.6 b LA growth rate (m .day ) 0.66±0.18 a 0.61±0.05 a 0.70±0.10 a 0.02±0.01 b 0.12±0.04 b 1480±238 ab 822±186 bc 1554±144a 97±59 c 197±50 c 324.2±34.8 a 168±17.5 b 220.6±20.9 b 14.8±9.1 c 43.8±11.9 c 48.5±2.2 a 44.9±2.0 a 50.5±2.2 a 20.8±0.1 b 38.6±6.1ab 6.8±0.7 a 3.9±0.3bc 4.6±0.4 b 0.7±0.4 c 1.1±0.4 bc Berry long diametre (mm) n=48 24.6±0.3 c 29.5 ±0.3 a 29.9±0.2 a 26.3±0.2b 26.7±0.3 b Berry firmness (N) 11.3±0.5 c 17.5±0.7 a 16.8±0.5 a 14.1±0.5 b 13.6±0.5 b 16.1±0.2 17.4±0.5 16.2±0.9 17.5±0.3 17.7±0.9 5.5±0.1 bc 6.8±0.3 a 6.3±0.3 ab 5.3±0.1 c 5.7±0.1 c Flower Drop (%) n=10 2 Bunch weight (g) Berries number -1 n=10 n=10 Rachis length (cm) n=10 Bunch compactness SSC (°Brix) TA (g.L ) -1 72 n=5 n=10 n=48 n=6 n=6 7th International Table Grape Symposium Table2. Effect of shade and GA3 treatments on percentage of flower drop and on shoot and primary leaf area (LA) growth rates during shade period and bunch and berry quality at harvest, on ‘Crimson Seedless’ vines (mean±SE). Different letters (a,b,c) express significant differences between treatments (P ≤ 0.05). Crimson Seedless Control GA3 (1ppm) GA3 (4ppm) SH_50B SH_100B 58.4±9.4 55.4±7.3 63.4±5.2 77.1±4.2 58.0±3.9 Shoot growth rate (cm.day-1) n=6 0.71±0.12 0.48±0.08 0.53 ±0.11 0.38±0.02 0.32±0.04 LA growth rate (m .day ) 0.25±0.05 0.19±0.02 0.28±0.09 0.10±0.03 0.10±0.01 727±38 810±91 684±52 566±98 821±114 275±31 a 299±23 a 195±15 ab 144±25 b 285±34 a 39.7±1.7 41.1±1.1 39.3±2.2 45.1±2.1 45.9±2.2 6.6±0.7 a 7.2±0.5 a 4.9±0.3 ab 3.6±0.6 b 6.3±0.8 a Berry long diameter (mm) n=48 23.0±0.2 ab 22.3±0.2 b 23.9±0.3a 23.2±0.2ab 20.8±0.3 c Berry firmness (N) 14.2±0.5 b 17.8±1.0 a 13.6±0.5 b 15.3±0.6 ab 14.7±0.6 b 20.4±0.5 a 17.6±0.5 c 19.9±0.4 ab 20.1±0.2 ab 18.3±0.3 bc 4.4±0.2 bc 5.4 ±0.2 a 4.3±0.1 bc 3.9±0.1 c 4.6±0.1 b Flower Drop (%) n=10 2 Bunch weight (g) Berries number -1 n=10 n=10 Rachis length (cm) n=10 Bunch compactness SSC (°Brix) TA (g.L ) -1 n=6 n=10 n=48 n=6 n=6 Acknowledgements This work was supported by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) through the project “VitiShade: PTDC/AGR-GPL/116923/2010” and the PhD grant SFRH/BD/69076/2010 to S.D.,by ProDer: ProdUva23921/2/3/4 Action4.1 and by the company Herdade Vale da Rosa. References Dokoozlian NK, Peacock WL. 2001. Gibberellic acid applied at bloom reduces fruit set and improves size of ‘Crimson Seedless’ table grapes. HortScience 36(4):706–709. ORAL SESSION 6 Domingos S, Scafidi P, Oliveira MC, Di Lorenzo R and Goulao LF. 2013. Effects of light reduction at bloom on fruit set in Black Magic table grape cultivar in early and late production cycles.18th International GiESCO Symposium, July 8-12Porto, Portugal.Cienc. Tec.Vitivinic./ American Journal of Enology and Viticulture 28(2): 1001-1005. Ferree DC, McArtney SJ and Scurlock DM. 2001. Influence of irradiance and period of exposure on fruit set of srenchamerican hybrid grapes. Journal of the American Society for Horticultural Science 126: 283-290. Lohitnavy N, Bastina S and Collins C. 2010. Early leaf removal increases flower abscission in Vitis vinifera ‘Semillon. Vitis 49(2):51-53. Lopes C and Pinto PA. 2005. Easy and accurate estimation of grapevine leaf area with simple mathematical models. Vitis 44(2): 55-61. Di Lorenzo R, Gambino C and Scafidi P. 2011. Summer pruning in table grape. Advances in Horticultural Science 25(3):143-150. Reynolds AG, Roller JN, Forgione A and De Savigny C. 2006. Gibberellic acid and basal leaf removal: implications for fruit Maturity, vestigial seed development, and sensory attributes of sovereign coronation table Grapes. American Journal of Enology and Viticulture 57(1): 41-53. Roubelakis KA and Kliewer WM. 1976.Influence of light intensity and growth regulators on fruit-set and ovule fertilization in grape cultivars under low temperature conditions. American Journal of Enology and Viticulture 27: 163167. 7th International Table Grape Symposium 73 Effects of PGRs (GA3 and CPPU) and cane girdling on yield, quality and metabolic profile of cv Italia table grape G Ferrara1,, A Mazzeo1, AMS Matarrese1, C Pacucci1 and V Gallo2,3 Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti - University of Bari ‘Aldo Moro’, via Amendola 165/A - 70126 Bari (Italy) 2 DICATECh, Politecnico di Bari, via Orabona 4 – 70125 Bari (Italy) 3 Innovative Solutions S.r.l. – Spin Off company of Politecnico di Bari, zona H 150/B Noci (Bari, Italy) *Corresponding author: Email: [email protected] 1 Background and Aims In Italy, 41% of table grape area is cultivated with cultivar Italia with a yield of 574,000 tons (Puglia Region, 2010). Puglia, in Southeastern Italy, is the most important region for table grape production (32,450ha) and ‘Italia’ table grape (15,000ha) is one of most important cultivars in the overall regional table grape production (ISMEA, 2012). Berry size is the main quality factor affecting sales of table grapes in international markets. Berry size is genetically predetermined among cultivars, but it can be considerably increased by crop load adjustment (Dokoozlian et al., 1994), bunch and berry thinning (Sharples et al., 1955), trunk girdling (Dokoozlian et al., 1994), and the use of plant growth regulators (PGRs). The use of PGRs is common in table grape viticulture (either seeded or seedless grapes), and more limited is their application for wine grape cultivars. Gibberellins (GAs) are PGRs commonly applied to many table grape cultivars. The mechanism of GAs is the stimulation of cell elongation and division, with higher sugar and water intake into the cells. The compound generally used is gibberellic acid (GA3) isomer, which is commonly applied after berry-set to increase berry size (Dokzoolian et al., 2001). Other PGRs used in table grape viticulture are cytokinins. In nature, cytokinins are produced in tissues where there is an intense cellular activity such as germinating seeds, fruits growth, and especially root tips. Cytokinins are used for berry growth (Retamales et al., 1995) because they stimulate cell division in association with auxins. They also regulate the cellular metabolism by acting on the synthesis of RNA, DNA and proteins. Sometimes they are applied with GAs in order to obtain a double effect: cell division (cytokinins) and elongation (gibberellins). The most common cytokinin used in viticulture (USA, Chile, South Africa, Italy) is forchlorfenuron with the trade name CPPU (N-(2-chloro-4-pyridyl)-N’-phenylurea) and Sitofex (registered name in Italy). Trunk or cane girdling consists of removing a ring of bark (phloem tissue) from either the vine trunk or canes to restrict the movement of assimilates from the aerial portion of the vine to the roots in order to increase the berry size (Dokoozlian et al., 1995). ORAL SESSION 6 This trial was carried out in a commercial vineyard in order to verify the effects of GA3, CPPU and girdling, on morphological, chemical, qualitative and yield parameters; the effects of GA3, CPPU and girdling on metabolic profile of the berries were also studied by nuclear magnetic resonance (NMR) spectroscopy. Experimental Procedure The study was carried out in 2011 and 2012 in a commercial vineyard located in Turi (Bari), in the Puglia region, Southeastern Italy. The vineyard was planted in 2002, with Italia cultivar grafted onto 34 E.M. (V. berlandieri × V. riparia). The grapevines, similar in vigour and crop load, were spaced 2.4×2.4m, trained to an overhead trellis system (‘tendone’) and drip irrigated (3,000-3,200m³.ha-1). The experimental design was a randomised block with three replicates for each treatments; each replicate consisted of three grapevines. The concentration and the times of application are listed in Table 1. At harvest, yield, berry size, chemical characteristics, berry texture, skin colour and metabolic profile were determined. NMR data were submitted to principal component analysis (PCA) after bucketing the spectra in small regular regions (0.04ppm). PCA is multivariate unsupervised statistical method that reduces the dimensionality of data to a subspace consisting in a few principal components (PCs). Such PCs are related to directions of largest amount of the variance in the spectra matrix. Table 1. Treatments, time of application and concentration. Treatment 74 Véraison Time of application Concentration T1 Control T2 Girdling Berry-set T3 GA3 10-11mm berry 10ppm T4 CPPU 11-12mm berry 9.75ppm 7th International Table Grape Symposium Discussion and Significance of the Study Significant differences were measured for yield and morphological parameters. All treatments improved morphological parameters; in particular, the treatment with girdling and PGRs presented the highest yield per vine and produced larger berries than the control in both years. With regards to the chemical parameters, in 2011 °Brix resulted lower in GA3 compared to control, whereas the acidity was significantly lower in all the treatments with respect to the control. In 2012 differences were observed only for pH values. No significant differences were found among treatments for berry firmness and berry detachment force in both years. Colourimetric parameters showed differences mainly in 2011, and berries of GA3and CPPU-treated and girdled vines presented higher value of h° (a shift from yellow to pale yellow-green) with respect to the control. The NMR studies showed that from June to October, the relative amount of glutamine decreased while valine, leucine, isoleucine, alanine, lactic acid and arginine increased. In the low-field region, signals intensities of caffeic acid gradually decreased during ripening, reaching negligible values at maturity. The differences between the samples were due to (glucose+fructose)/(malic acid) ratio which was found higher in 2012. Tartaric acid amount was almost constant for both years. CPPU increased berry size to a less extent with respect to other works in different conditions (Dokoozlian et al., 1994; Zabadal and Bukovac, 2006), whereas the effects of GA3 and girdling were similar to what was previously reported. In our conditions, all the treatments affected the morphological parameters with an increase of the berry size, but with some negative effects on skin colour. This late aspect could be considered for extending the storage of the bunches on the vine and for consumers preferring table grape with a less intense yellow colour. Metabolomic approach indicated that samples collected at ripening (October) in 2011 could be better differentiated than those harvested in the same period of 2012. In fact, in 2011, cane girdling and application of CPPU caused a higher production of ethanol in the berries, whereas application of GA3 resulted in a higher content of glutamine, proline, leucine and arginine. The effects of cane girdling and the application of CPPU or GA3 in 2012, could not be appreciated as in the previous year. In conclusion, the PGRs improved berry size but induced a slight change of the skin colour which resulted in a pale yellow-green; some differences were also detected in the metabolic profile. Acknowledgements ORAL SESSION 6 The authors would like to thank Isabella Cafagna (Politecnico di Bari) and Mariangela Vezzoso (Innovative Solutions S.r.l.) for technical help and Prof. Piero Mastrorilli (Politecnico di Bari) for helpful discussion on NMR metabolic profiling. The authors also thank Giuseppe Netti for allowing the trial in the vineyard and for his important support both in the field and in the lab and Andrea Pacifico for technical help. References Dokoozlian NK, Luvisi DA, Schrader PL and Moriyama MM. 1994. Influence of trunk girdle timing and ethephon on the quality of Crimson Seedless table grapes. Proceedings of the International Symposium on Table Grapes Production, Anaheim, CA, USA pp. 237-240. Dokoozlian N, Luvisi DA, Moriyama M and Schrader P. 1995. Cultural practices improve colour, size of ‘Crimson Seedless’. California Agriculture 49: 36-40. Dokoozlian NK, Ebisuda N and Hashim JM. 2001. Gibberellic acid bloom spray reduce fruit set and improve packable yield of ‘Autumn Royal’ table grapes. Journal of the American Pomological Society 55: 52-57. Retamales J, Bangerth F, Cooper T and Caliejas R. 1995. Effects of CPU and GA3 on fruit quality of Sultanina table grape. Acta Horticulturae 188: 149-157. Sharples GC, Hilgerman RH and Milne L. 1955. The relation of cluster thinning and trunk girdling of Cardinal grapes to yield and quality of fruit in Arizona. Proceedings of the Society for Horticultural Science. 65: 225-233. Zabadal TJ and Bukovac MJ. 2006. Effect of CPPU on fruit development of selected Seedless and seeded grape cultivars. HortScience 41: 154-157. 7th International Table Grape Symposium 75 Effect of CPPU (N-(2-chloro-4-pyridinyl)-N’-phenylurea) and a seaweed extract on Crimson Seedless grape quality Janéne Strydom* ARC Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch 7599, South Africa, Tel: + 27 (0) 809 3159, E-mail: [email protected] Background and Aims Application of GA3 (gibberellic acid) in combination with CPPU (N-(2-chloro-4-pyridinyl)-N’-phenylurea) may result in larger berries (Dokoozlian et al., 1994; Wolf et al., 1994; Zoffoli et al., 2009). However, excessive use of CPPU can also reduce TSS (total soluble solids) and result in reduced berry colour (Peppi and Fidelibus, 2008; Wolf et al., 1994). Seaweed extract can, depending on the dosage, improve brightness and redness of Trakya Ilkeren grapes (Kok et al., 2010) and improve berry firmness of Sultanina (Norrie et al., 2002). The study aimed to determine whether CPPU and a seaweed extract, containing auxins, cytokinins and nutrients, can be included with GA3 as part of a berry enlargement programme on Crimson Seedless without negative effects on other quality attributes. Experimental Procedure and Results The trial was conducted on 4-year-old Crimson Seedless (Vitis vinifera L.) grafted onto Ramsey (Vitis champinii) on the commercial farm Roepersfontein in the Lower Orange River region (LOR) of South Africa during the 2008/09 season. Climate data were recorded (Figure 1). The micro-irrigated grapevines were spaced 3.0m x 2.5m on a sandy soil and trained onto a pergola trellis system. Across all treatments, standard viticultural practices were applied according to guidelines for preparation of export grapes (Greyling, 2007). The trial was laid out as a randomised complete block design with five treatments, replicated in six blocks with one grapevine per experimental unit. The five treatments consisted of a control (standard berry enlargement spray application of 20ppm GA3 with 400g.kg-1 gibberellins active ingredient), seaweed extract (0.3% v/v solution of Ecklonia maxima derivative with 11/0.031mg.L-1 Auxins/Cytokinins) in combination with standard GA3, and three dosages of CPPU (10ppm active ingredient) applied at dosages of 2, 3 and 4ppm in combination with standard GA3. ORAL SESSION 6 All CPPU treatments were applied at 6-10mm berry diameter in a mixture with the standard GA3 berry enlargement spray. The seaweed extract treatments were applied five times, commencing at 50% flowering and repeated at 1-4mm, 6-10mm, 12-15mm and 15-16mm berry diameter. Bladbuff 5® (250mL.1000L-1), was used as pH buffer for all treatments. Treatments were applied as bunch directed sprays to ensure full coverage of bunches. Plastic curtains between grapevines prevented spray drift. Fifty berries were sampled randomly from each experimental grapevine at harvest. Ten randomly-selected bunches from each of the data grapevines were harvested, weighed and packed for cold storage. The freshly sampled berries were used to determine berry diameter, visual grape colour, as well as TSS, TTA (total titratable acidity) and anthocyanin concentration. A colour chart from the Department of Agriculture Forestry and Fisheries (DAFF) was used to group berries into different colour classes, from dark (class 1) to light (class 9) (DAFF 1990). Evaluations for loose berries, SO2 damage, berry crack, decay, soft tissue breakdown and external bruises were done after five weeks in cold storage at -0.5°C, followed by one week at 7.5°C. After cold storage, 30 randomly sampled berries were used to determine berry firmness using a pressure probe at 1mm press setting to apply force onto the berry skin surface, without penetrating the skin. Data were statistically analysed at a 5% significance level to facilitate comparison between the treatment means. Three and 4ppm CPPU significantly increased berry diameter compared to the control. Compared to the control, only 4ppm CPPU significantly decreased TSS. All the CPPU treatments significantly increased TTA. Although none of the CPPU treatments had a significant effect on berry skin colour compared to the control (Figure 2), all CPPU treatments significantly decreased anthocyanin concentration (Table 1). The seaweed extract treatment resulted in a significantly darker berry skin colour than all the CPPU treatments, but not compared to the control. Four ppm CPPU significantly increased the percentages of SO2 damage, bruises and total defects after cold storage (Table 2). Split berries contributed most to total defects and there were no significant differences between treatments. Berry firmness was significantly increased by the seaweed extract treatment compared to the control (Table 2). 76 7th International Table Grape Symposium Table 1. Effect of treatments on berry size and grape quality variables of Crimson Seedless from Roepersfontein in the Lower Orange River region (2008/09). Treatment Berry diameter (mm) Total soluble solids (°Brix) Total titratable acidity (g.L-1) Anthocyanin concentration (mg/g FWb) 18.50 bc* 18.95 a 5.39 b 0.26 a 2 ppm CPPU 19.27 ab 18.47 a 5.84 a 0.17 b 3 ppm CPPU 19.62 a 18.37 ab 5.70 a 0.18 b 4 ppm CPPU 19.68 a 17.32 b 5.96 a 0.17 b Seaweed extract 18.38 c 19.17 a 5.36 b 0.25 a Control a a a *Means followed by the same letter in each column did not differ significantly (P=0.05). aN-(2-chloro-4-pyridinyl)-N’-phenylurea. bFW = Fresh berry weight. Table 2. Effect of treatments on defects and berry firmness of Crimson Seedless from Roepersfontein in the Lower Orange River region (2008/09) after 6 weeks (5 weeks at -0.5°C plus 1 week at 7.5°C) of cold storage (2008/09). Treatment* Total loose berries (%) SO2 damage (%) Decay (%) Split berries (%) Soft tissue breakdown (%) Bruise (%) Total defects (%) Berry firmness after cold storage (g) Control 1.57 a* 0.74 bc 0.14 a 1.33 a 0.14 a 0.48 b 4.40 b 107.91 b 2ppm CPPU 1.47 a 0.87 bc 0.02 a 3.71 a 0.00 a 0.59 b 6.66 ab 117.93 ab 3ppm CPPU 2.18 a 1.27 ab 0.10 a 2.20 a 0.09 a 1.32 ab 7.16 ab 117.21 ab 4ppm CPPU 1.50 a 1.88 a 0.09 a 3.12 a 0.11 a 1.77 a 8.47 a 114.06 ab Seaweed extract 1.64 a 0.28 c 0.02 a 3.28 a 0.03 a 0.94 ab 6.19 ab 120.01 a a a a *Means followed by the same letter in each column did not differ significantly (P=0.05). a N-(2-chloro-4-pyridinyl)-N’-phenylurea. ORAL SESSION 6 Figure 1. Mean monthly temperature and rainfall for Roepersfontein in the Lower Orange River region (2008/09 season), South Africa (ARC-ISCW, 2008). Tmax = mean monthly maximum temperature; Tmin = mean monthly minimum temperature. 7th International Table Grape Symposium 77 Figure 2. The effect of CPPU (N-(2-chloro-4-pyridinyl)-N’-phenylurea) and a seaweed extract on visual colour of Crimson Seedless berries from Roepersfontein in the Lower Orange River Region in the 2008/09 season (significance of differences at P = 0.05 indicated with letters). Discussion and Significance of the Study The 3ppm CPPU treatment was considered the most suitable CPPU dosage in this study because it significantly increased berry diameter without a concomitant significant decrease in TSS. Although 3ppm CPPU significantly increased TTA and significantly decreased anthocyanin concentration, the maturity index was still within norms for export and the lighter coloured Crimson Seedless grapes were suitable for export (DAFF, 1990). Three ppm CPPU did not have a significant effect on any of the cold storage defects. ORAL SESSION 6 The increased berry diameter obtained with 3ppm and 4ppm CPPU compared to the control corresponds with previous results where CPPU in combination with GA3 increased berry size of Thompson Seedless (Dokoozlian et al.; Zoffoli et al., 2009). The significant decrease in TSS observed in the 4ppm CPPU treatment compared to the control and the significant increase in TTA observed in all CPPU treatments compared to the control are in accordance with the results of Dokoozlian et al. (1994) and Zoffoli et al. (2009). The significant decrease in anthocyanin concentration caused by all the CPPU treatments compared to the control are similar to the significant decrease in the amount of anthocyanins per berry skin surface area of Flame Seedless grapes treated with CPPU in combination with GA3 (Peppi and Fidelibus, 2008). However, apart from the effect of CPPU on anthocyanin pigments, the reduction in anthocyanin concentration might also be related to the fact that maximum temperatures during the ripening period rose above 30°C (Figure 1). Above 30°C, anthocyanin biosynthesis is reduced (Mori et al., 2005) and anthocyanin pigments are degraded (Mori et al., 2007). Similar to the significant increase in berry firmness caused by the seaweed extract in this study, Norrie et al. (2002) reported an increase in berry firmness of Sultanina treated with 1.5L.ha-1 Ascophyllum nodosum extract applied twice pre-bloom, twice at bloom and twice during post-bloom. The incidence of split berries may be attributed to rain during the ripening period (Figure 1). The lack of significant differences in the percentage of loose berries caused by CPPU compared to the control is in contrast with studies where CPPU in combination with GA3 increased the percentage of loose berries of Thompson Seedless, Red Globe and Ruby Seedless (Zoffoli et al., 2009). The significant increase in SO2 damage and bruises that resulted from 4ppm CPPU in combination with GA3 compared to the control may be related to the significantly larger berries from the 4ppm CPPU treatment compared to the control. The results of one season indicated that 3ppm CPPU could be used, in combination with GA3, to increase berry diameter of Crimson Seedless, without detrimental effects on grape colour and TSS. This can impact on the yield and number of cartons exported. The seaweed extract was not effective in increasing berry size of Crimson Seedless, but it did increase berry firmness. To make final recommendations, the trial should be repeated to verify results. 78 7th International Table Grape Symposium Acknowledgements The author would like to thank Philagro South Africa for funding this research, as well as Roepersfontein farm in the Lower Orange River region for the use of their vineyard and assistance by their staff and staff of ARC InfruitecNietvoorbij (Viticulture Division) for technical assistance. References ARC-ISCW, 2008. Private Bag X79, Pretoria, South Africa, 0001. DAFF (Department of Agriculture, Forestry and Fisheries), 1990. Export standards and requirements for table grapes: Directorate Food safety and quality assurance. Private Bag X343, Pretoria, 0001, South Africa. Dokoozlian NK, Moriyama MM and Ebisuda NC. 1994. Forchlorfenuron (CPPU) increases the berry size and delays the maturity of Thompson Seedless table grapes. In: Rantz, J.M. & Lewis, K.B. (eds). Proceedings International Symposium Table Grape Production. American Society for Enology and Viticulture, June 1994, Anaheim, California, USA. pp. 63-68. Greyling M. (ed.) 2007. Guidelines for preparing export table grapes. Capespan Ltd. P.O. Box 505, Belville, 7535, South Africa, 77pp. Kok D, Bal E, Celik S, Ozer C. and Karauz A. 2010. The influences of different seaweed doses on table quality characteristics of cv Trakya Ilkeren (Vitis Vinifera L.). Bulgarian Journal of Agricultural Science 16: 429-435. Mori K, Goto-Yamamoto N, Kitayama M and Hashizume K. 2007. Loss of anthocyanins in red-wine grape under high temperature. Journal of Experimental Botany 58: 1935-1945. Mori K, Sugaya S and Gemma H. 2005. Decreased anthocyanin biosynthesis in grape berries grown under elevated night temperature condition. Scientia Horticulturae 105: 319-330. Norrie J, Branson T and Keathley PE. 2002. Marine plant extracts impact on grape yield and quality. Acta Horticulturae 594: 315-319. Peppi MC and Fidelibus MW. 2008. Effects of forchlorfenuron and abscisic acid on the quality of Flame Seedless grapes. HortScience 43: 173-176. Wolf EEH, Viljoen JA, Nieuwenhuys A. and Loubser JT. 1994. The effect of forchlorfenuron on bunch quality in table grapes. In: Rantz, J.M. & Lewis, K.B. (eds). Proceedings International Symposium Table Grape Production. American Society for Enology and Viticulture, June 1994, Anaheim, California, USA. pp. 50-53. Zoffoli JP, Latorre BA and Naranjo P. 2009. Preharvest applications of growth regulators and their effect on postharvest quality of table grapes during cold storage. Postharvest Biology and Technology 51: 183-192. ORAL SESSION 6 7th International Table Grape Symposium 79 Evaluation of table grape colouration programs in global production areas Robert Fritts, Jr.*, Schalk Reynolds, Gonzalo Maturana, Francisco Casanova, Johan Pienaar and Jozsef Racsko Valent BioSciences Corporation, 870 Technology Way, Libertyville, IL 60048, USA *Corresponding Author: Tel: +1 559 299-2741, Email: [email protected] Background and Aims Globally, table grape production tends to be from warmer growing regions that are generally considered difficult colouring areas for quality coloured varieties. Fruit colour development can be influenced by a number of factors including the cultivar, rootstock, plant vigour, climate, canopy management, light exposure, crop load, irrigation, fertilisation, and plant growth regulators. Consequently, achieving optimal fruit colour requires a programmatic approach rather than the use of a single tool or practice. In some years colour development is further challenged due to extreme environmental conditions. Harvests are often delayed while waiting for sufficient colour. Due to the delay in harvest, quality (e.g., firmness) declines, and market prices become lower. Under those conditions, the desired colour may never develop and a significant portion of the crop may not be harvested. Growers often suffer substantial economic losses under these conditions. Anthocyanins are the major contributors to berry colour; responsible for the red, scarlet, violet and purple colours in grape berries. Research has shown that application of the abscisic acid (S-ABA) to grape clusters increases fruit colour in several varieties (Lee and Tomana, 1980; Kondo et al., 1998; Jeong et al., 2004; Peppi et al., 2006). Since 2009, nine international registrations have been granted to Valent BioSciences Corporation (VBC) for the commercial use of S-ABA to accelerate the colour development of red table grapes. Two formulations of S-ABA, a 20% Water Soluble Granule and a 10% Soluble Liquid; have been commercialised under the trade name of ProTone™. During the 1970s, the plant growth regulator ethephon was introduced as a tool to help improve colour development of grapes; however, ethephon can be inconsistent and can cause berry softening at higher use rates (Dokoozlian et al., 1998). In addition, in recent years ethephon residues have come under increased scrutiny, with the Maximum Residue Limit (MRL) being lowered to 0.7mg.kg-1 in the European Union (EU) markets. ORAL SESSION 6 The use of ProTone, alone, or in combination with ethephon, has significantly improved the options of commercial grower to meet the demands of international markets for low residues and highly coloured premium table grapes. These practices have been adopted in the major table grape growing regions of Chile, South Africa, Mexico, Israel, Egypt, Peru and California. Results have been similar in response worldwide; however, this report will focus on ProTone development programs in South Africa, Chile, and Mexico to produce highly coloured premium table grapes that meet the stricter EU residue requirements. Experimental Procedure and Results Commercial ‘Flame Seedless’ table grape vineyards were selected for these field trials. Application timing was keyed to véraison. For purposes of ProTone application, véraison was defined as the point in which 50% of the berries have softened. ProTone and ethephon were applied at various rates using electrostatic or traditional airblast sprayers, at 100 to 1250 litres per hectare. Split rate and sequential timing treatments were also incorporated into the programs. Plot sizes varied from one to several hectares encompassing multiple rows within each vineyard. At commercial harvest fruit in the blocks of each treatment were evaluated. The numbers of harvests varied from two to four, depending on the site. Fruit were commercially harvested and total weight from within each treatment was separately tallied. In addition to yield data, fruit firmness and soluble solids were recorded at harvest for each treatment at each vineyard site. Samples for ethephon residues were taken prior to harvest and determined by commercial analytical laboratories. 80 7th International Table Grape Symposium Table 1. Ethephon residues (mg.kg-1) resulting from spray programs using different spray volumes, spray equipment and total quantities of ProTone and ethephon in South Africa in 2012. Spray Program Water Volume (L.Ha-1) Sprayer Type Total Ethephon (480 g.L-1) Per Ha Ethephon Residue (mg.kg-1) @ Days After Last Application 1kg ProTone 750mL Ethephon 750mL Ethephon 100 1,500 1,500 ESS Nobili Nobili 1,500mL 0.99 @ 8 d 0.41 @ 14 d 1kg ProTone 750mL Ethephon 500g ProTone + 750mL Ethephon 100 100 100 ESS ESS ESS 1,500mL 0.89 @ 7 d 0.43 @ 13 d 1 kg ProTone 750mL Ethephon 1kg ProTone + 750mL Ethephon 750mL Ethephon 100 1,500 100 1,500 ESS Nobili ESS Nobili 2,250mL 1.64 @ 8 d 2.83 @ 13 d 3.1 @ 19 d 1.88 @ 23 d 975mL Ethephon 975mL Ethephon 455mL Ethephon 1,300 1,300 1,300 Nobili Nobili Nobili 2,405mL 1.23 @ 10 d 1.28 @ 22 d Ethephon residues levels varied depending on the timing of the analysis. Residue values tended to decrease as the number of days from the last ethephon application increased. Higher field use rates of ethephon exhibited higher residue levels that persisted for longer periods of time. In some cases, it was necessary to divert fruit to alternate markets due to levels above the established EU MRL of 0.7mg.kg-1. Discussion and Significance of the Study Our findings are in strong agreement with earlier studies that S-ABA (ProTone) can be an effective tool to improve colour development in red table grapes and increase the productivity of grape growers (Peppi et al., 2006; Ferrara et al., 2013). S-ABA (ProTone) can be used from véraison to late in the harvest season to increase berry colour and subsequent harvestable yields. In addition, programs incorporating ProTone with ethephon can be utilised to reduce ethephon residues, while maintaining highly coloured premium table grapes for international markets. References ORAL SESSION 6 Dokoozlian N, Peacock B, Luvisi D and Vasquez S. 1998. Cultural practices for ‘Crimson Seedless’ table grapes. UC Coop Tulare Co. Ext. Pub. TB 16-00. Ferrara G, Mazzeo A, Matarrese AMS, Pacucci C, Pacifico A, Gambacorta G, Faccia M, Trani A, Gallo V, Cafagna I and Mastrorilli P. 2013. Application of abscisic acid (S-ABA) to ‘Crimson Seedless’ grape berries in a Mediterranean climate: Effects on colour, chemical characteristics, metabolic profile and S-ABA concentration. Journal of Plant Growth Regulation 32: 491-505. Jeong ST, Goto-Yamamoto N, Koayashi S and Esaka M. 2004. Effects of plant hormones and shading on the accumulation of anthocyanins and the expression of anthocyanin biosynthetic genes in grape berry skins. Plant Science 167: 247-252. Kondo S, Masuda E and Inoue K. 1998. Relationship between ABA application and fruit quality of ‘Pionnier’ grape (Vitis sp.). Acta Horticulturae 464: 35-40. Lee J-C and Tomana T. 1980. Physiological study on the colouration in grape. II. Effect of sucrose, abscisic acid, and indoleacetic acid on the anthocyanin development in ‘Kyoho’ grape (Vitis labruscana). Korean Journal of Horticultural Science and Technology 21: 158-163. Peppi MC, Fidelibus MW and Dokoozlian N. 2006. Abscisic acid application timing and concentration affect firmness, pigmentation and colour of ‘Flame Seedless’ grape. HortScience 41: 1-6. 7th International Table Grape Symposium 81 Improving table grape colouring programs with s-abscisic acid (Protone™): the importance of application technology Schalk Reynolds*, Robert Fritts Jr, Rick Hopkins, Johan Pienaar and Jozsef Racsko Philagro SA, PO Box 442, Somerset West, 7130, South Africa *Corresponding Author, Tel: +27 (0) 21 851-4163, Email: [email protected] Background and Aims Colour is a major quality determinant of red table grapes. Grower profitability largely depends on the efficacy of colouring programs. Therefore, considerable attention has been given recently to vineyard management factors to improve colour development in red table grapes. Besides other technology elements, the use of plant growth regulators has become standard grower practice to improve berry colour. Ethephon and S-abscisic acid (ProTone) have been registered for this purpose. While the effect of ethephon on berry colour development is often erratic and can cause berry softening (Peppi et al., 2006), S-abscisic acid (ProTone) has been reported to be a more effective and reliable way to improve berry colouration (Lee and Tomana, 1980; Cantin et al., 2007; Ferrara et al., 2013). In addition, field evidence for berry colouring has shown that S-abscisic acid (ProTone) is not translocated within the plant or within the cluster. The goal of this study was to investigate the importance of application technology in colouring efficacy of ethephon or ethephon plus S-abscisic acid (ProTone); various types of sprayers and spray volumes were tested in South Africa and California, USA. Experimental Procedure and Results Field trials were conducted in commercial table grape vineyards in South Africa (ZA) and California, USA (CA) to study the effect of application technology on colouring. ‘Flame Seedless’ variety was selected. Two spray treatments were applied; 1.) Ethephon at 0.90L.ha-1 (ZA) and 1.17L.ha-1 (CA) and 2.) ProTone at 1kg.ha-1 tank mixed with Ethephon. Applications begun at véraison (i.e., 80% berry softening in ZA and 50% of the berries softened in CA) and repeated 3 days (ZA) or 7 days (CA) thereafter. Three water volumes were tested: 500L, 1,000L and 1,500L per hectare in CA, and two volumes; 500L and 1,000L in ZA. Also, two sprayer types were tested for coverage; one was a Cima-like (Spectrum sprayer) and the other one a Nobili type (Pak-Blast sprayer, Atasa sprayer). ORAL SESSION 6 All treatments included fluorescent dye to observe coverage of the spray solution. Spray coverage, i.e., fluorescent dye coverage, on berries in each treatment was determined under UV light. Colour development of the clusters from véraison to harvest was recorded at the CA trial site, and total yield at commercial harvest in ZA. These trials were successful in demonstrating the improved efficacy of ethephon plus S-abscisic acid (ProTone) compared with single ethephon spray as a colour enhancing product for red table grapes. Both sprayer types worked well for colouring when properly calibrated. Spray deposition ratings between the front and back of bunches were generally more uniform for application with the Cima-like spray system than the Nobili type (Atasa) system, for both spray volumes (Figure 1). Atasa Cima Figure 1. Droplet pattern between Atasa and Cima vineyard sprayer at 500 L/ha in South Africa. It was noticed that smaller droplet sizes and spray direction (upwards from beneath) gives better coverage and thus better colour. In general, spray coverage and efficacy were improved in CA as volume increased. Excessive volume, however, may increase water droplets on the bottom of berries (Figure 2). 82 7th International Table Grape Symposium Back Bottom Front Figure 2. Water droplets on grape berries when sprayed with 1000L/ha using a Pak-Blast (Nobili / Atasa type) sprayer in California. Also, higher volume may increase disease incidence. Colour development in ZA, determined on both side of the bunch, was significantly more advanced where vines were sprayed with a tank mix of ProTone and ethephon using the Cima-like applicator at a spray volume of 500L.ha-1, compared to other treatments. Discussion and Significance of the Study Our findings support earlier studies that the addition of S-abscisic acid (ProTone) in the ethephon spray can significantly improve efficacy for colour development in red table grapes compared with untreated control or single ethephon sprays. Although differences in spray coverage exist between various types of applicators and spray volumes, adequate colouring can be achieved by proper calibration. In summary, colouring programs for table grapes can be optimised by proper calibration and attention to water droplet deposition using currently available spray equipment. Incorporation of S-abscisic acid (ProTone) into these programs has been shown to be successful in producing highly coloured premium table grapes for international markets. References Cantin CM, Fidelibus MW, and Crisosto CH. 2007. Application of abscisic acid (ABA) at véraison advanced red colour development and maintained postharvest quality of ‘Crimson Seedless’ grapes. Postharvest biology and technology 46: 237-241. ORAL SESSION 6 Ferrara G, Mazzeo A, Matarrese AMS, Pacucci C, Pacifico A, Gambacorta G, Faccia M, Trani A, Gallo V, Cafagna I, Mastrorilli P. 2013. Application of abscisic acid (S-ABA) to ‘Crimson Seedless’ grape berries in a Mediterranean climate: Effects on colour, chemical characteristics, metabolic profile and S-ABA concentration. Journal of Plant Growth Regulation 32: 491-505. Lee J-C and Tomana T. 1980. Physiological study on the colouration in grape. II. Effect of sucrose, abscisic acid, and indoleacetic acid on the anthocyanin development in ‘Kyoho’ grape (Vitis labruscana). Korean Journal of Horticultural Science and Technology 21: 158-163. Peppi MC, Fidelibus MW, and Dokoozlian N. 2006. Abscisic acid application timing and concentration affect firmness, pigmentation and colour of ‘Flame Seedless’ grape. HortScience 41:1-6. 7th International Table Grape Symposium 83 Session 7. Table grape growing in tropical/subtropical environments and dormancy Keynote address Challenges and opportunities to growing table grapes in sub-tropical/ tropical regions Patricia Coelho de Souza Leão Embrapa tropical Semi-Arid, BE 428, Cm 152, Box 23, Zip Code 56302-970, Petrolina, PE, Brazil, Tel:+55(87) 3866 3668, Email: [email protected] Tropical and subtropical viticulture can be defined in five types according the Multicriteria Climatic Classification (Tonnieto and Carbonneau, 2004): tropical dry, tropical wet, tropical alternatively dry/wet, sub-tropical alternatively dry/wet and sub-tropical dominantly wet. They include a wide range of countries and very particular tropical viticultures in Brazil, Peru, Venezuela, Colômbia, Guatemala, India, Thailand, and others characterised as subtropical in the South of Brazil, Uruguay, Korea, Japan and others. The vine adapts differentially in every climatic condition by imposing a particular management system, resulting in varied yield and quality of grapes. Thus, the focus here is going to be in the dry tropical viticulture, highlighting growing regions like Piura in northern Peru (05° 12’00 “S 80° 38’00” W), Zulia in Venezuela (10° 57 ‘51 “N, 71° 44 ‘8” W) and Petrolina and Juazeiro, in the Northeast of Brazil (9° 23’ 39 “S, 40 ° 30 ‘35” W). Viticulture in these regions are the nearest of the Equador line in the world and have higher similarities between them. São Francisco Valley can be considered as an example for this group as one of the pioneers and most technically advanced for growing table grapes. The climate presents an average annual precipitation of 505mm, annual average relative humidity of 60.7%, annual average temperature, maximum, and minimum, respectively 26.7°C, 32.0°C, and 20.8°C. The main common aspects in viticulture under tropical climate are that vine grows continuously, there is no rest period in winter and can be made up to three crops at any time of year. As the buds do not come into physiological dormancy, they are apt to sprout at any time of year that pruning is performed. This is the main comparative advantage in tropical viticulture, the grower can decide what is the most convenient time of year for pruning and harvesting grapes as a function to achieve better prices in the market. To produce table grapes in these conditions, it is possible to list the main technical challenges, as follows: ORAL SESSION 7 • • • • • • Breaking dormancy and reducing apical dominance; Controlling of vigour and vegetative growth; Rational water and nutrients management; Management of clusters for growth and colouring of berries; Phytosanitary control; Controlling of ripening and ideal time to harvest. In addition to these challenges in the field is also necessary to ensure post-harvest conservation of grape through appropriate methods and practices during packaging, storage and transportation to markets. All the above mentioned challenges are associated with a major challenge that is to achieve sustainability, where the technical challenges are aligned to the use of efficient methods of business management in order to reduce production costs and ensure economic viability. In conclusion, tropical viticulture is developing fast in the world and presents some comparative advantages. The better comprehension of the vine physiology to adapt in these environmental conditions and the advancing of new research approaches can be the key to obtain high quality grapes for the more strict markets and sustainability by combining yield stability and low production costs. Reference Tonietto J and Carbonneau A. 2004. A multicriteria climatic classification system for grape growing regions wordwide. Agricultural and Forest Meteorology 124(1-2): 81-97. 84 7th International Table Grape Symposium Comparative transcriptomic study of bud dormancy in sub-tropical and Mediterranean climates Oliver Berkowitz1,2, Michael Considine1,3,4,* and JA Considine1 School of Plant Biology, University of Western Australia, Crawley 6009 WA Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley 6009 WA 3 Institute of Agriculture, University of Western Australia, Crawley 6009 WA 4 Department of Agriculture and Food Western Australia, South Perth 6151 WA *Corresponding author: Tel. +618 6488 1783, Email: [email protected] 1 2 Background and Aims Normal developmental transitions from bud dormancy to bud burst, to flowering and fruit initiation are in synchrony with seasonal changes and their disruption can impact on grape production. Bud dormancy is an important survival strategy in perennial plants including grapevine with key regulators of dormancy being temperature, especially accumulated chilling time, and photoperiod (Carmona et al., 2008). As bud dormancy is a quantitative state, suboptimal chilling conditions in sub-tropical regions will lead to poor bud burst with subsequent yield penalties. This often needs intervention by application of chemicals such as hydrogen cyanamide to increase and synchronise bud burst (Halaly et al., 2008). The regulation of bud dormancy and its modulation under sub-optimal climatic conditions is currently poorly understood. Increased understanding of underlying molecular mechanisms will allow for the development of improved management strategies in varying climates. The aim of our study was therefore to analyse dormant buds from two sites in sub-tropical Carnarvon (Western Australia) against a control site with a Mediterranean climate in the Swan Valley close to Perth. This was done at two time points (pre- and post-chilling) by analysis of change in the transcriptome using next-generation sequencing technology (RNA-seq) to identify key regulators and genetic networks involved in the regulation of the dormancy states. Experimental Procedures and Results Bud material of the variety ‘Crimson seedless’ was sampled pre-chilling at the end of March (subtropical Carnarvon, WA) and early April (Mediterranean Swan Valley, Perth) and post-chilling early and mid June, respectively. RNA was extracted from the sampled buds using the Sigma Spectrum Plant Total RNA kit with a modified protocol in 4 biological replicates each. Corresponding libraries were generated after ribosomal RNA depletion and sequenced on an Illumina HiSeq1500 instrument. Read mapping and differential gene expression analysis was performed using the TopHat/Cufflinks pipeline (Trapnell et al., 2012). Genes with an at least 3-fold change and FDR<0.05 were called as differentially expressed. Hierarchical cluster analysis was performed in the R environment and GO term enrichment analysis with the ClueGO plugin for Cytoscape (Bindea et al., 2009). ORAL SESSION 7 Results. The RNA-seq approach yielded close to 1 billion sequencing reads across all biological replicates with an average of 40 million per sample. Reads where mapped to the grape reference genome (Pinot Noir PN40024, 12x coverage, Jaillon et al., 2007) and on average 80% of reads could be mapped. This will allow for the identification of differences in transcript sequences (e.g. SNPs, indels), composition (e.g. presence/absence) and structure (e.g. alternative splicing) between the reference genome and the ‘Crimson seedless’ variety. This analysis was followed by detailed bioinformatic analyses of gene expression using e.g. hierarchical clustering, pathway and gene ontology analyses. Expression of genes for the two sub-tropical sites (CRV1, CRV2) was compared to the Mediterranean control site (SV) to identify differences in their bud development. For the pre-chilling time point there were approx. 1100 differentially expressed genes (DEGs) for the CRV1 vs. SV comparison, while for CRV2 only approx. 260 showed differences in expression level when compared to SV. Post-chilling this number increased slightly to around 340 gene while decreasing for CRV1 to 660 genes (Table 1). Table 1: Number of DEGs (compared to control site SV) at different time points and sampling sites. Timepoint / site Pre-chilling Post-chilling CRV1 CRV2 CRV1 CRV2 Up-regulated 902 136 601 219 Down-regulated 132 132 63 124 7th International Table Grape Symposium 85 Hierarchical cluster analysis of these DEGs combined identified 7 clusters of genes with distinct expression patterns. For several of these clusters we were able to identified a number of gene ontology (GO) terms specifically enriched that are related to e.g. developmental and hormonal processes (Table 2). Table 2: GO term enrichment in DEG clusters. Cluster # Enriched GO terms Cluster 1 Auxin transport Lipid metabolism Cluster 2 Cell growth Chromatin organisation Microtubule-based process Leaf development Cluster 4 Negative regulation of molecular function Response to nitrogen Cluster 6 Response to high light Iron transport Cluster 7 Pectin metabolism Cell wall organisation In addition a number of genes coding for key regulators of development, i.e. transcription factors of the MADS-box family, showed also difference in expression levels in the buds originating from the three sites. Discussion and Significance of the Study This study has identified key mechanisms important in the regulation of bud dormancy in sub-tropical climates down to the molecular level. In addition, application of RNA-seq technology provides proof-of-concept for further analyses using next-generation technologies in non-model grape varieties. This increase in knowledge will help in the development of improve management practices for table grape growers in suboptimal climates and help to ensure industry viability and growth. Acknowledgements This work was supported by the Australian Research Council (Linkage Project LP0990355) with contributions from the Department of Agriculture and Food of Western Australia and the Gascoyne Table Grape Growers Association. References ORAL SESSION 7 Bindea G, Mlecnik B, Hackl H, Charoentong P, Tosolini M, Kirilovsky A, Fridman WH, Pages F, Trajanoski Z and Galon J. 2009. ClueGO: a Cytoscape plug-in to decipher functionally grouped gene ontology and pathway annotation networks. Bioinformatics 25: 1091-1093. Carmona MJ, Chaib J, Martinez-Zapater JM and Thomas MR. 2008. A molecular genetic perspective of reproductive development in grapevine. Journal of Experimental Botany 59: 2579-2596. Halaly T, Pang X, Batikoff T, Crane O, Keren A, Venkateswari J, Ogrodovitch A, Sadka A, Lavee S, and Or E. 2008. Similar mechanisms might be triggered by alternative external stimuli that induce dormancy release in grape buds. Planta 228: 79-88. Jaillon O, Aury JM, Noel B, Policriti A, Clepet C, Casagrande A, Choisne N, Aubourg S, Vitulo N, Jubin C, Vezzi A, Legeai F, Hugueney P, Dasilva C, Horner D, Mica E, Jublot D, Poulain J, Bruyere C, Billault A, Segurens B, Gouyvenoux M, Ugarte E, Cattonaro F, Anthouard V, Vico V, Del Fabbro C, Alaux M, Di Gaspero G, Dumas V, Felice N, Paillard S, Juman I, Moroldo M, Scalabrin S, Canaguier A, Le Clainche I, Malacrida G, Durand E, Pesole G, Laucou V, Chatelet P, Merdinoglu D, Delledonne M, Pezzotti M, Lecharny A, Scarpelli C, Artiguenave, F, Pe ME, Valle G, Morgante M, Caboche M, Adam-Blondon AF, Weissenbach J, Quetier F and Wincker P. 2007. The grapevine genome sequence suggests ancestral hexaploidization in major angiosperm phyla. Nature 449: 463-467. Trapnell C, Roberts A, Goff L, Pertea G, Kim D, Kelley DR, Pimentel H, Salzberg SL, Rinn JL, and Pachter L. 2012. Differential gene and transcript expression analysis of RNA-seq experiments with TopHat and Cufflinks. Nature Protocols 7: 562-578. 86 7th International Table Grape Symposium Low temperature-dependent release from dormancy involves a transient oxidative burst in grapevine (Vitis vinifera) buds K Meitha1, D Konnerup1, TD Colmer1, CH Foyer2, CS Gordon3, JA Considine1, MJ. Considine1,3* School of Plant Biology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia Centre of Plant Science, Research of Integrative and Comparative Biology, Faculty of Biological Science, University of Leeds, Leeds, LS2 9JT, United Kingdom 3 Department of Agriculture and Food WA, 3 Baron-Hay Crt, South Perth, WA, 6151, Australia *Corresponding author: Tel:+ 61 8 6488 1783; Email [email protected] 1 2 Background and Aims The state of dormancy in perennial plants is an evolutionary trait that enables the plant to endure harsh winter condition. This inherent state allows the survival of the bud meristem inside tight protective layers, with a slowed metabolism, conserving energy during conditions unfavourable for growth. Once conditions become favourable, the bud meristem will resume growth and differentiate into specialised tissues, reproduce and prepare for the subsequent winter (Lavee and May 1997). Hence the seasonal cues that drive the activity state are vital to the reproductive fate of grape vine as one of economically important temperate fruit species. Production in climates and seasons outside the normal seasonal requirements is problematic, due to the influence of climate on coordinated growth cycles (Shulman, Nir et al., 1983). This often requires intensive and expensive intervention to achieve a viable crop. For example, the use of chemical agents to promote uniform bud burst in warmer climates, which lack the normal, temperate, winter-spring transition. Advanced knowledge of plant oxygen signalling in bud meristem development will be beneficial to future research focussing on better bud burst management. In our study, we measured internal oxygen partial pressure (pO2) and respiration, as the fundamental drive of metabolism, growth and adaptation in plants, and in situ detection of reactive oxygen species (ROS) as vital signal in the processes (Tsukagoshi, Busch et al., 2010; Kelliher and Walbot 2012). The results are expected to lead innovation in managing seasonal production of grapevine in optimal and stressed conditions. Experimental Procedure and Results ORAL SESSION 7 Internal pO2 and CO2 production were measured to determine whether low oxygen levels (hypoxia) and changes in respiration rates play roles in bud burst regulation. To study hypoxia, internal pO2 in buds were measured at 3, 24, and 72 h after removal from chilling (4°C) and kept in the dark and also after 24 and 72 h in 12/12 photoperiod (P) condition, using the Oxygen MicroSensor system (Unisense, Aarhus). Measurements were also performed on buds from which the outer scales had been removed 10min prior to measurement. Micro-electrodes (OX-25µm) were gradually inserted into the buds in 25µm steps to a depth of 2000µm, which mostly were reaching the meristem (Figure 1a). An extremely low pO2 was observed in almost all internal parts of 3h treated buds, which value was less than 7kPa (Figure 1b). The pO2 increased gradually as dormancy in buds progressed to release after 24-72 hours treatment, with a more rapid oxygenation when grown in a 12/12 P compared to complete darkness (Figures 1c-d). It also showed that removing external scales of dormant buds resulted in marked oxygenation of the outer 50-80% of the bud transect within three hours (Figure 1b). Respiration rates were recorded as CO2 production. Prior to this, 4 buds per measurement were harvested from dark (3, 24, 72 and 144h) and 12/12 P (24, 72 and 144h) treatments, weighed and placed onto thin agar on plates. Sections of the agar, as buds bases, were removed from plate and then plus buds on it were placed in a portable insect respiration chamber (6400-89, LI-COR, Nebraska) connected to a LI-6400XT portable gas exchange system. Measurements were performed at 23°C, in air (380µmol. s-1 CO2) with 100µmol.s-1 air flow in darkness. The system was allowed to stabilise for 10 minutes in the dark and then CO2 production rates were recorded. Increase in CO2 production rates was observed from 3, 24 to 72 hours buds with a steep decline occurred when buds were grown in darkness for 144 hours (Figure 2). 7th International Table Grape Symposium 87 Figure 1.(a) Trace of micro-electrode insertion in bud is pointed by the black arrow, 2000µm depth; (b) Internal oxygen partial pressure in 3 hours treated buds (green:complete buds in dark, blue:peeled buds); (c) 24 hours (green:kept in darkness, black:in 12/12 photoperiod); (d) 72 hours (green:kept in darkness, black:in 12/12 photoperiod). Figure 2. Respiration rates as CO2 production measured in the absence of light (green: kept in darkness, black: in 12/12 photoperiod). Means +/- SE, n≥4. ORAL SESSION 7 Hypoxia is known to regulate ROS production, such as superoxide, to signal the break of dormancy. Superoxide accumulation in dormant buds and prior to burst were analysed in situ by nitro bluetetrazolium (NBT) staining method. This was adapted from experiment in pea nodule (Groten, Vanacker et al., 2005) with modification. In this experiment, 0.2 mg.mL-1 NBT in phosphate buffer (10mM, pH 7.8) staining was used to all time points (0, 3, 24, 72 and 144h) treated in 12/12 P. The buds were receiving formaldehyde fixation and Steedman’s wax embedding afterwards. Then, they were sectioned into 35µm thickness, dewaxed, cover-slipped and scanned at magnification 20X by Aperio Scanscope LX (Leica Biosystem) at The Center of Characterisation and Microscopy - UWA. The results revealed that superoxide activity in the meristem tissue was only detected in 0h bud (Figure 4a), then it disappeared after the bud was kept for 3h at 23°C. However, superoxide accumulation was still detected in developing vascular tissues at 3 to 144h buds (Figures 4b-e). 88 7th International Table Grape Symposium Figure 3. In situ localisation of superoxide via nitrobluetetrazolium in dormant grape bud and commencing burst. Stained section from 0 (a), 3 (b), 24 (c), 72 (d), and 144 (e) hours after removal from cold storage/4°C and maintained at 23°C with 12/12 photoperiod treatment. The blue colouration indicates superoxide accumulation in the provascular tissues (PVT) and meristem (M). Discussion and Significance of the Study Low oxygen condition or hypoxia is known to play a role in promoting dormancy release in grapevine buds. Genes expression analysis on non- and hydrogen cyanamide (HC) treated buds showed that pyruvate decarboxylase (VvPDC), alcohol dehydrogenase (VvADH), sucrose synthase (VvSUSY) and NON-symbiotic haemoglobin (VvnsHB), which are categorised as hypoxic related genes, were transiently up-regulated when the buds approached burst (Vergara, Rubio et al., 2012). Furthermore, the regulation of a transcription factor related to dormancy release (Flowering Locus T; VvFT) was also increased (Vergara, Rubio et al., 2012). While these research imply that there might be a hypoxic condition prior to bud burst in grapevine, the application of oxygen-sensitive microelectrode in our study has allowed us to directly determine oxygen partial pressure (pO2) within buds internal tissues, and yet to verify whether it is hypoxic or not. ORAL SESSION 7 Hypoxia was observed in almost all internal parts of the dormant buds after 3h treatment with pO2 was less than a third of normal oxygen pressure in air. A sudden increase was recorded when the scales were removed from buds after treated similarly, which indicates that the lignified external layer of scales are a major barrier to oxygen diffusion. A marked oxygenation in buds kept in 12/12 P condition suggests that light influenced this process. However, it does not indicate whether this process is entirely physical or physiological Currently, there is very little understanding of respiration in grapevine buds, despite their importance in fruitfulness and spatial variation in development in vineyards. Poor conditions for bud dormancy can result necrosis of the inflorescence primordium, spatial variation in the vineyard, as determined by coordination of bud burst and variable fruitfulness. A better understanding of respiratory control, will improve the knowledge and development of improvement management of grape vine responses to environmental signals, such as changes in temperature and photoperiod. In our study, we showed increase in respiration rates as buds kept longer (3 - 72h) in warmer temperature that may be a result of higher internal pO2. We also suspect buds disability to initiate sugar producing through photosynthesis in those kept in darkness for 6 days has caused significant decreased in respiration rate. Hypoxia is known to generate superoxide accumulation in dormant buds cells, which further activates antioxidant defence system (Vergara, Parada et al., 2012). Previous molecular studies showed the elevation of antioxidant defence genes such as Catalase (CAT) that reached its maximum peak prior to bud burst and decreased to a third after that (Perez and Lira 2005). The suspension of catalase activity during bud recess period implies the importance of hydrogen peroxide (H2O2) as dormancy release agent. In concurrence with hypoxia and antioxidant genes expression, Superoxide Dismutase (SOD) activity also increased and showed a similar pattern with CAT production (Pacey-Miller, Scott et al., 2003). This enzyme helps hydrogen peroxide accumulation by enhancing its production 7th International Table Grape Symposium 89 from superoxide. While most researches focused on the analysis of molecular aspects, this experiment investigated the accumulation and localisation of superoxide, as precursor of hydrogen peroxide, in the internal tissues of dormant buds and commencing release by in situ staining. The disappearance of blue-formazan from bud meristem area after they were kept at 23°C for 3 hours suggest that temperature change is one of many factors influencing superoxide regulation. However, superoxide was still detected in the developing vascular tissues in buds from all treatment (0-144h), which presumably supplies the requirement of high H2O2 signal to precede bud burst. In summary, there is a hypoxic condition in the internal tissues of dormant grapevine buds, which gradually become more oxygenated as dormancy release progresses. The oxygenation process of internal tissues might increase respiration rates prior to bud burst. Temperature change has helped superoxide regulation in bud meristem, which may further regulate its development. This knowledge of how internal oxygen level and temperature change influence other processes during dormancy release is fundamental to discover better methods in bud burst management. Acknowledgements This work was in part supported by the Australian Research Council (Linkage Project LP0990355) with contributions from the Department of Agriculture and Food of Western Australia and the Gascoyne Table Grape Growers Association. Plus an Australia Awards Scholarship (2012 - 2016) and a Travel Grant from Grape and Wine Research and Development Corporation (2013) to Karlia Meitha. References Groten K, Vanacker H, Dutilleul C, Bastian F, Bernard S, Carzaniga R and Foyer CH. 2005. The roles of redox processes in pea nodule development and senesence. Plant, Cell and Environment 28: 1293-1304. Kelliher T and Walbot V. 2012. Hypoxia Triggers Meiotic Fate Acquisition in Maize. Science 337: 345-348. Lavee, S. and May P. (1997). Dormancy of grapevine buds - facts and speculation. Australian Journal of Grape and Wine Research 3: 31-46. Pacey-Miller T, Scott K, Ablett E, Tingey S, Ching A and Henry R. 2003. Genes associated with the end of dormancy in grapes Received: Functional and Integrative Genomics 3: 144-152. Perez FJ and Lira W. 2005. Possible role of catalase in post-dormancy bud break in grapevines.” Journal of Plant Physiology 162: 301-308. Shulman Y, Nir G, Farbenstein L and Lavee S. 1983. The effect of cyanamide on the release from dormancy of grapevine buds. Scientia Horticulturae 19: 97-104. Tsukagoshi H, Busch W and Benfey PN. 2010. Transcriptional regulation of ROS controls transition from proliferation to differentiation in the root. Cell 143: 606-616. ORAL SESSION 7 Vergara R, Parada F, Rubio S and Perez FJ. 2012. Hypoxia induces H2O2 production and activates antioxidant defence system in grapevine buds through mediation of H2O2 and ethylene. Journal of Experimental Botany 63(11): 41234131. Vergara R, Rubio S and Perez FJ. 2012. Hypoxia and hydrogen cyanamide induce bud-break and up-regulate hypoxic responsive genes (HRG) and VvFT in grapevine-buds. Plant Molecular Biology 79: 171-178. 90 7th International Table Grape Symposium Influence of external dormancy release forcing factors on grapevine bud dormancy and the concomitant changes in bud respiration Y Velappan1, M.J. Considine1,2,*, JA Considine1 and CH Foyer 1,2 School of Plant Biology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia Centre for Plant Sciences, University of Leeds, Leeds, West Yorkshire LS2 9JT, United Kingdom * Corresponding author: Tel: 6488 1783, E-mail: [email protected], 1 2 Background and Aims Temperate perennial plants like grapevine cycle between periods of growth and dormancy in synchrony with the seasons. Dormancy is a critical to (i) protect the meristem from unfavourable conditions and (ii) set the state of the meristem to enable rapid and sustainable resumption of growth when suitable conditions arise (Rohde and Bhalerao, 2007). The cycling in and out of quiescence is orchestrated by various environmental, genetic and metabolic factors. Temperature and photoperiod are considered to be key environmental signals controlling or influencing bud dormancy (Li et al., 2003; Heide et al., 2005). During late summer, waning photoperiod and temperature cause growth cessation followed by the initiation of apical buds which are held in an internally governed quiescent state to protect the apical meristem. Exposure to adequate amounts of winter chilling is required to release buds from endodormancy which is later followed by a period of ecodormancy, which lasts until the temperature rises sufficiently before the resumption of growth. Though control of dormancy and uniform bud burst are of prime importance in commercial grape production, our current knowledge about the factors governing bud dormancy and burst is limited. Managing bud dormancy is an enormous economic problem for perennial fruit industries. Hydrogen cyanamide (H2CN2) is typically used to artificially break dormancy in the warm winter regions. Although it is effective and relatively cheap, it imparts phytotoxicity if mismanaged. Further, the mechanism of action of cyanamide involved has not been completely elucidated (Shulman et al., 1983; Perez et al., 2008; Walton et al., 2009). But from previous studies, it has been postulated that following the application of HC, there is a perturbation in the activity of the cytochrome pathway in the mitochondria resulting in respiratory and oxidative stress which temporarily triggers the production of reactive oxygen species (ROS) in addition to downregulating the tricarboxylic acid (TCA) cycle and the production of ATP, inducing anaerobic respiration. Simultaneously, the antioxidant machinery and the relevant pathways are upregulated to cope with the increased ROS production (Nir and Lavee, 1993; Pe´rez et al., 2007; Ophir et al., 2009; Vergara et al., 2012). All the above reprogramming under hypoxic conditions may activate the cell cycle, relieving the dormant state and promoting resumption of growth (Sweetlove et al., 2002; Ophir et al., 2009). However, the crosstalk between hypoxia, respiration, cell cycle regulation and oxidative signalling during dormancy release has not been clearly understood. ORAL SESSION 7 This study sought to determine the optimal time for application of hydrogen cyanamide for the Crimson Seedless variety and understand the regulation of these factors mentioned above, especially respiration, in relation to oxidative signaling during dormancy in grapevine buds. The effects of hydrogen cyanamide and/or chilling on dormant grapevine buds were explored as a tool to investigate these processes. Experimental Procedure and Results The above aim was achieved by combining expertise in cell biology and whole-plant physiology with state of the art molecular biology to study how 2.5% v/v commercial dose of Hydrogen cyanamide (HC) and cold treatments (4°C) influenced respiration and bud burst kinetics at different stages of grapevine (Vitis vinifera L cv. Crimson Seedless) bud dormancy. Buds collected from April to August with an interval of ~30 days was subjected to HC (2.5% v/v) and/ or 360h cold treatments. The bud burst kinetics was scored for 70 days for each treatment condition and respiration (O2 and CO2) was measured in field conditions on the day of sampling and after 360h of 4°C chilling, using.LiCor (LI6400XT) CO2 analyzer and Unisense O2 micro-electrode. It was observed that all the conditions used to force budburst had a negligible or negative effect on bud burst response in May and June. There was a decline in the overall percentage of bud burst compared to the control which showed progressive increase in overall percentage of bud burst from April to June. It could therefore be inferred that the buds were not fully primed to withstand harsh environmental conditions and thus were sensitive to the forcing conditions used in this study resulting in DNA or cell damage which might have delayed bud burst. HC and cold treatment of the buds at certain stages of dormancy is expected to accelerate initiation of cell division in the buds and hence the bud burst (Gai et al., 2013). Cold treatment was thus found to have a positive effect on buds collected in July and August by inducing an earlier bud burst compared to the control. 7th International Table Grape Symposium 91 Respiration should increase linearly as the buds progress from endodormancy to ecodormancy and then increase rapidly towards bud burst (Mc Pherson et al., 1997). In accordance to this, a gradual increase in oxygen consumption was observed from April to August. However, the carbon dioxide produced showed an undulating pattern resulting in a similar pattern of respiratory quotient. It was therefore estimated that respiratory quotient would increase after August due to a shift towards anaerobic respiration as the buds progress towards the end of endodormancy. Discussion and Significance of the Study Overall, the comparative analysis of the effect of commercial HC and/or cold treatment on bud burst response and respiration of grapevine buds in relation to the time of sampling indicated a notable change in trend from July. Continuing the study further until September will help in developing a better picture of the basic events that take place throughout endodormancy and help in selecting the important time points that need to be explored further in the context of cell cycle and respiration. Bud dormancy is elementary to the study of developmental processes in temperate perennials and its regulation is of great economic importance to fruit and horticultural industries. Respiration along with various other metabolic processes is known to be highly regulated during dormancy. However, our current understanding of the factors regulating dormancy is very limited and is based on various gene expression studies that are less precise and hence cannot directly relate to spatial organization, activity or function. Moreover, no significant research has been done on grapevine buds to study respiration. Hence this research will be the first to elucidate the role and regulation of respiration during dormancy in grapevine buds. References Gai S, Zhang Y, Liu C, Zhang Y, Zheng G. 2013. Transcript Profiling of Paoenia ostii during Artificial Chilling Induced Dormancy Release Identifies Activation of GA Pathway and Carbohydrate Metabolism. PLoS One 8: e55297. Heide OM and Prestrud AK. 2005. Low temperature, but not photoperiod controls growth cessation and dormancy induction and release in apple and pear. Tree Physiology 25:109-114. Li C, Junttila O, Ernstsen A, Heino P, Palva ET. 2003. Photoperiodic control of growth, cold acclimation and dormancy development in silver birch (Betula pendula) ecotypes. Physiologia Plantarum, 117:206-212. Mc Pherson HG, Snelgar WP, Manson PJ, Snowball AM. 1997. Bud Respiration and Dormancy of Kiwifruit (Actinidia deliciosa). Annals of Botany 80:411-418. Nir G and Lavee S. 1993. Metabolic changes during cyanamide induced dormancy release in grapevines. Acta Horticulturae 329:271-274. Ophir R, Pang X, Halaly T, Venkateswari J, Lavee S, Galbraith D, Or E. 2009. Gene-expression profiling of grape bud response to two alternative dormancy-release stimuli expose possible links between impaired mitochondrial activity, hypoxia, ethylene-ABA interplay and cell enlargement. Plant Molecular Biology 71: 403-423. Pérez F, Rubio S, Ormeno-Nu´nez, J. 2007, Is erratic bud-break in grapevines grown in warm winter areas related to disturbance in mitochondrial respiratory capacity and oxidative metabolism? Function Plant Biology, 34: 624-632. ORAL SESSION 7 Pérez F, Vergara R, Rubio S. 2008. H2O2 is involved in the dormancy-breaking effect of hydrogen cyanamide in grapevine buds. Plant Growth Regulators 55: 149-155. Rohde A and Bhalerao R P. 2007. Plant dormancy in the perennial context. Trends in Plant Science, 12: 217-223. Shulman Y, Nir G, Fanberstein L, Lavee S. 1983. The effect of cyanamide on the release from dormancy of grapevine buds. Scientia Horticulturae 19: 97-104. Sweetlove, L. J., Heazlewood, J. L., Herald, V., Holtzapffel, R., Day, D. A., Leaver, C. J., & Millar, A. H. 2002. The impact of oxidative stress on Arabidopsis mitochondria. The Plant Journal 32:891-904. Vergara, R., Parada, F., Rubio, S., & Perez, F. J. (2012) Hypoxia induces H2O2production and activates antioxidant defence system in grapevine buds through mediation of H2O2 and ethylene. Journal of Experimental Botany 63(11): 4123-4131. Walton EF, Wu RM, Richardson AC, Davy M, Hellens RP, Thodey K, Schaffer R J. 2009. A rapid transcriptional activation is induced by the dormancy-breaking chemical hydrogen cyanamide in kiwifruit (Actinidia deliciosa) buds. Journal of Experimental Botany 60: 3835-3848. 92 7th International Table Grape Symposium Control of grape bud dormancy release C Zheng, T Halaly and E Or* Department of Fruit Tree Sciences, Volcani center, ARO, Israel *Corresponding author: Email: [email protected] In warm winter regions, where the table grape industry preferentially is located, artificial induction of bud dormancy release is mandatory for coordinated, early production of economical grape yields. The single effective artificial stimulus available for commercial use in vineyards is hydrogen cyanamide (HC). Unfortunately, its ability to induce respiratory stress, which initiates a biochemical cascade that leads to effective dormancy release, is also responsible for its toxicity, both to the vines and within the environment. The development of safe alternatives for artificial induction of bud dormancy release is essential due to the initiative to ban its use in the near future. Such task requires comprehensive understanding of the cascade of biochemical changes that is induced by the currently available artificial stimuli of grape bud dormancy release. Our genomic studies recently led to the development of a working model for such cascade. According to this model, perturbation of the cytochrome pathway activity within the mitochondria leads to respiratory and oxidative stress, expressed as an increase in the levels of reactive oxygen species, decreased activity of the tricarboxylic acid cycle, and decreased production of ATP. To address this energy crisis, the alternative oxidase pathway, glycolysis, pyruvate metabolism and anaerobic respiration are induced, in an order that has yet to be defined. In parallel, the cellular antioxidant machinery and related pathways are upregulated to cope with the oxidative burst. Changes in redox, sugar, and Ca++ metabolism, resulting from the above reprogramming, under conditions that mimic hypoxia, may be responsible for induction of ethylene biosynthesis. Such changes may then affect the interplay between ethylene and abscisic acid (ABA) in a way that allows removal of ABA repression on meristem activity and induces changes that lead to growth resumption. Our post genomic studies, which have affirmed the predictive power of the model, support a central role for ethylene and ABA in regulation of dormancy release and question the involvement of Gibberellins, will be described. ORAL SESSION 7 7th International Table Grape Symposium 93 Oral Presentation Abstracts FRIDAY 14 NOVEMBER 2014 Session 8. General Viticulture and Vine Physiology Plastic rain covers affect canopy microclimate and fruit quality of table grapes Matthew W. Fidelibus*1 and Stephen J. Vasquez2 Department of Viticulture and Enology, University of California, Davis, CA 95616-5270 USA. University of California Cooperative Extension, 1729 S. Maple Ave., Fresno, CA 93702 USA *Corresponding author: Tel. 15596466510, Email: [email protected] 1 2 Background and Aims Table grapes are a labor and material intensive crop; annual operating expenses may exceed $9,000 per acre in California (Peacock et al., 2007). Thus, it is critically important for growers to protect late season grapes from rain, as exposure to precipitation in the weeks before harvest can stimulate the development of rots and molds that render them unmarketable. Rain damage may be avoided by harvesting the fruit before 1 October, after which time the chance of rain increases considerably, especially in the north-central San Joaquin Valley. However, the grapes of some late maturing varieties may not have achieved optimal market quality by then and the price paid for grapes often increases towards the end of the season, thus providing an incentive to harvest fruit as late as possible. To help prevent precipitation from wetting the clusters of grapes, and thereby extend the potential harvest season, growers may cover their vines with a sheet of polyethylene film (Novello and DePalma, 2008). The films, which are generally about 1 mil thick and 100 inches wide, are typically deployed in late August or early September, and installed in such a way that they form an uninterrupted cover along the entire length of the row (Gerawan and Zweigle, 2005). The film is generally supported by the trellis and vine canopy, and is thus in direct contact with the grapevines’ leaves. Films of different colour and transparency are commonly used, but whether those differences may affect canopy microenvironment and fruit quality has not been determined. The aim of this study was to determine how different plastic covers affect the canopy microclimate, and fruit quality, at harvest, and after postharvest storage. Experimental Procedure and Results In late September, ‘Red Globe’ (in 2011) and ‘Autumn King’ (in 2012) table grape vines were covered with green or white plastic films, or left uncovered (Figure 1), and canopy microclimate, rot incidence, and fruit yield and quality at harvest, and after postharvest storage, were evaluated. ORAL SESSION 8 The green film was more transparent and less reflective than the white. The films had little effect on fruit zone temperatures, but the daily maximum temperature in the top center of the canopy of vines covered with green film was consistently 5°C higher than that of vines subjected to other treatments (Figure 2). Treatment effects on relative humidity (RH) depended on location within the canopy and time of day, but both films consistently reduced evaporative potential under the covers, though not in the fruit zones. Treatment effects on condensation beneath the films were inconsistent, but south facing surfaces generally had less condensation than vertical or north 94 7th International Table Grape Symposium Figure 1. Green (foreground) and white (midground) plastic rain covers, with uncovered vines in the background. facing surfaces. Approximately 1 inch of rain fell on 4 October 2011, but no rain occurred during the experimental period in 2012. Green films slightly delayed fruit maturation in 2011, but not in 2012. Films did not affect the number of boxes harvested, or postharvest fruit quality in 2011, but fruit from covered vines had less postharvest rot in 2012 than fruit from non-covered vines, approximately 44% of the ‘Autumn King’ grape clusters from uncovered vines had signs of rot compared to 18% for vines under either colour of film, even though significant rain occurred in 2011 but not 2012. Figure 2. Average diurnal temperatures in the top center of the canopy of Autumn King grapevines uncovered, or covered with green or white plastic film September 25 through October 14, 2012. Discussion and Significance of the Study The films had some consistently different effects on canopy microclimate, with the white films having less undesirable effects than the green films. Both films appeared to reduce the incidence of postharvest rot, but addition data are needed to determine whether effects on rot are consistent. Acknowledgement Support for this research was provided by the California Table Grape Commission. References Gerawan M and Zweigle D. 2004. Tie down for plastic grape canopy. United States Patent 6813859. Novello V and DePalma L. 2008. Growing grapes under cover. Pages 353-362 in: Proc. ISHS on grape production and processing. Eds.: P.G. Adsule et al., Acta Hort. 785, ISHS, 2008. Peacock WL, Vasquez SJ, Hashim-Buckey JM, Klonsky KM and DeMoura RL. 2007. Sample costs to produce table grapes: Crimson Seedless, San Joaquin Valley - South. University California Coop. Ext. Dept. Agr. Resource Econ., Davis. ORAL SESSION 8 7th International Table Grape Symposium 95 Identification and characterisation of factors affecting development of size diversity among berries in a clusters of cv. Early Sweet E Or*, O Oren, P KoilKonda, C Zheng, T Halaly, O Crane and AK Achampong Department of Fruit Tree Sciences, Volcani center, ARO, Israel *Corresponding author: Email: [email protected] Size diversity among berries in a cluster is a major quality concern in the seedless table-grapes industry. The presence of very small berries (‘shot berry’) on clusters with normal-size berries depends on genetic background, environmental conditions and horticultural practices. The high susceptibility of the leading early-ripening variety, ‘Early sweet’, to shot berry development under our growing regime is a major drawback for our growers, and thus the central motivation for the below reported study. Early application of GA is a known inducer of shot berry formation. It was earlier assumed that (1) GA-induced shot berry development is mediated by induction of parthenocarpy (2) the parthenocarpic nature of the shot berries is responsible for their inability to develop to the size of the stenopermocarpic berries on the same cluster, due to complete lack of endogenous GA. Interestingly, GA application did not lead to significant increase in shot berry size in such mixed clusters. To test the above assumptions and further understand the cause of size diversity within the cluster, a research system was established in the vineyards using gibberellin application at specific concentrations and time points to induce shot berry formation. Using this system we studied the effects of (1) parthenocarpy; (2) flower-load on the inflorescence; and (3) cluster load on the vine, on shot berry formation. The data, which agrees with some of the former assumptions and contradicts with others, will be presented, and our current understanding regarding the primary reason for size diversity will be discussed. ORAL SESSION 8 96 7th International Table Grape Symposium Irrigation strategy and vine performance of organic ‘Italia’ table grape grown in Apulia region (Southern Italy) Luigi Tarricone*, Giovanni Gentilesco, Domenico Di Gennaro and Antonio Maria Amendolagine Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Research Unit for Viticulture and Enology in Southern Italy, Via Casamassima, 148 -70010 Turi (BA) Italy *Corresponding author: Tel: +39 080/8915711, Email: [email protected] Background and Aims In the world there is an increasing fresh consumption of organic table grapes but its cultivation is very delicate and experience to advice organic growers is still quite lacking (Willer, 2011). Table grapes vines (Vitis vinifera L.) are always grown with irrigation in arid climate regions, characterised by low rainfall and high evaporative demand such as it occurs in Apulia region, Southern Italy (Tarricone et al., 2012). Water is a natural and non-renewable resource and the world nowadays is facing the problem of water scarcity due to climate change and the increase of world population, leading to increasing demand for food (Jones, 2007). Considering that 70% of the total water is consumed in crops’ irrigation, great attention should be focused on good agriculture irrigation management (Chaves et al., 2007). For these reasons there is a wide interest in deficit-irrigation of table grape vines because global climate changes increases the probability that hot summers and long dry periods occur (Ezzahouani and Williams, 2007). The need to optimise water use in table grapes growing has become more important as consequence of the limited water availability for agricultural use and of the increase in its cost. It’s known that limited water availability in the soil results in a decrease of canopy development, reduction of leaf assimilation rate, inadequate vine capacity to ripen the clusters, and consequently, decline of quantitative (number of clusters and berry size) and qualitative yield response. In contrast, excessive irrigation can cause vigourous vegetative growth, leading to reduced sugar accumulation in grapes and possible nitrate leaching to the groundwater by percolation.Therefore, the efficient application of strategic irrigation technologies not only allows to save water but also can play a positive role in improving the quality and profitability of table grapes. Nevertheless, a mild water deficit, e.g., 60-80% of full evapotranspiration (ET) for cv. ‘Thompson Seedless’, has improved marketable grape yield without penalising sugar accumulation and berry weight, and a 50% deficit irrigation after véraison has proved to not penalise berry size (Williams et al., 2010). The most common vineyard irrigation practice consists in the restitution of nearly full irrigation requirements during the early part of berry development and in allowing a slight water deficit during the final phases of the crop cycle. An alternative strategy is to adopt the water balance method (Allen et al., 1998) to estimate full irrigation requirements when crop coefficients are well adjusted and the reference evapotranspiration information is available. The present research evaluates the effect of two different water regimes on organic Italia table grape characteristics grown according to organic EC rules, in Apulia region. Experimental Procedure and Results ORAL SESSION 8 The trial was carried out in the years 2010-11, at an experimental farm of the Mediterranean Agronomic Institute in Valenzano, (latitude 41°02’N, longitude 16°53 E, elevation 70m, Bari province) on organic Vitis vinifera cv Italia, grafted onto Vitis berlandieri x Vitis Rupestris 1103 Paulsen rootstock, at a spacing of 2.30 x 2.30m apart (1.890 vines.ha-1), trained to overhead tendone system (Apulia type), cane pruned (40 buds per vine), drip-irrigated and covered with plastic film from véraison to delay harvest and to protect clusters from rain and hail. Italia table grape is the main white-berry seeded cultivar grown in Apulia region, late-ripening (from September in open field to December in vineyards covered with plastic film) and is characterised by high vine productivity, large berry size, muscat flavour, moderate juice acidity and long shelf-life on cold storage. The climate of the area is sub-arid Mediterranean (average maximum air temperature 33°C inAugust, average minimum air temperature 3°C in January, and rainfall averages 500mm per year, mostly concentrated from September to April) with high summer evaporation and low relative humidity. The 2010-2011 seasons were rainy years with a average rainfall of 790mm but with only 270mm from budbreak (April) to harvest (first week of October). Soil of the experimental vineyard is characterised by a medium chemical fertility and soil texture was clay-loam. 7th International Table Grape Symposium 97 Water content at field capacity and wilting point were 33 and 19g.100g-1 respectively and total available water was 12g.100g-1. Two watering volumes were applied: V1 (well irrigated vines) corresponding to 100% of estimated crop evapotranspiration (Etc) and V2 (moderately stressed vines) with 80% of Etc restitution and irrigation started after berry set (in June) to one week before harvesting (first week of October).Irrigation was provided through drip system with a single irrigation line per row and pressure compensated emitters, with a discharge rate of 16 and 12 l h-1 for V1 and V2 treatments respectively. Irrigation was scheduled using the water balance method (Allen et al., 1998) based on the soil water balance evaluation, by providing the restitution of the amount of water lost by evapotranspiration, after effective rainfall. Daily vine evapotranspiration (ETc) was calculated by Penman-Monteith (FAO) method and using FAO crop coefficients defined for table grape in Mediterranean region.The seasonal irrigation water volumes supplied through drip irrigation at the end of irrigation season (from June to October), were 2.700, 2850 and 2.200, 2300m3.ha-1 for V1 and V2 treatments respectively in 2010 and 2011 years. On 15 vines per irrigation treatment bud load per vine, shoots and clusters number per vine, bud fruitfulness, were assessed. Cluster number of vines was standardised one week after berry set in order to retain an average of 31 bunches per vine in all treatments with manual cluster thinning. To quantify vine water status, midday stem water potentials (Ψmds) were measured on 10 leaves of similar maturity per treatment with a pressure chamber (3005F01, Soilmoisture Equipment Corp., Santa Barbara CA, USA).Leaf stomatal conductance was determined on cloudless days during ‘midday’ period using a portable porometer (Model SC-1, Decagon Devicess, Pullman, WA). At the commercial harvest, on random samples of 45 clusters per treatment, bunch and berry mass, cluster length, berry diameters and yield per vine were determined. On juice samples the total soluble solids, titratable acidity and pH were also determined. Besides, 50 berries per treatment were randomly sampled and their skin firmness, berry removal force and firmness were determined using a digital penetrometer (Digital Fruit firmness tester, TR Turoni S.r.l., Forlì, Italy). On a sample of 100 berries per treatment the berry skin colour parameters by use of colourimeter (Minolta Croma Meter CR 400) L* (brightness), a* (measure of range colour from green (-) to red (+) and b* (measure of range colour from blue (-) to yellow (+) were determined. After the harvest, six vines per treatment were completely defoliated and total leaf area per vine determined with a leaf area meter (area-meter Li-3100, LI-COR, USA) and the leaf area/crop weight ratio was calculated (Kliewer and Dokoozlian, 2005). During winter period vegetative growth was quantified by measuring cane mass at pruning and the fruit to pruning weight ratio was calculated. Crop water productivity (kg of fresh fruit per m3 of water applied) was also computed. Average data were statistically analysed using procedure of Systat 11 package (SYSTAT Software Inc., Richmond, California, USA). Different irrigation volumes did not affect shoots and clusters number per vine, neither bud fruitfulness in the following crop cycle (Table 1). Table 1. Vegetative and productive characteristics of Italia vines (average 2010-11). Treatment ORAL SESSION 8 Buds per vine (n) Shoots per vine (n) Clusters per vine (n) Clusters per vine/Buds per vine Clusters per vine/Shoots per vine V1 40 a 32.56 a 34.41a 0.86 a 1.06 a V2 40 a 29.70 a 33.94 a 0.84 a 1.14 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. The vine water status showed clear differences between treatments. In V1, Ψmds varied at a little extent, ranging from -0.49 to -0.64MPa, while in V2, it decreased along the season reaching the value of -0.95MPa at harvest (Table 2). Differences in midday stem water potential were significant at pea-size, véraison and at harvest. V2 treatment had more negative Ψmds by 22% and 33% respectively, suggesting that midday stem water potential is an appropriate index of plant water status for table grape irrigation management. 98 7th International Table Grape Symposium At pea-size, véraison and harvest, the lower vine water status likely affected the stomata aperture as indicated by the reduction of stomata conductance (from 7 to 33%) in leaves of V2 treatment (Table 2). Compared to V1 treatment, a yield decline of 14% was observed for V2 treatments respectively, due to a reduction in cluster weight (-13%) and berry weight (-6%) considering the same clusters number retained per vine. The yield decline was due to a reduction in bunch and berry weight considering the same clusters number per vine (Table 3). The application of different irrigation volumes induced significant differences in total leaf area per vine. Leaf area of V1 (well-irrigated vines) was quantitatively higher than that of the other treatment (moderately-stressed vines) (Table 3) and maximum berry weight was obtained in V1 treatment which showed a leaf area (m2) per fresh yield (kg) ratio of 0.82 according to the results shown by Kliewer and Dookzlian (2005). Crop water productivity (production per unit of water applied) increased moderately from V1 (17.1kg.m-3) to V2 (18.1kg.m-3). Table 2. Effects of the irrigation regime on midday stem water potential and stomata conductance on Italia vines (average 2010-11). Midday stem water potential (Ψmds, MPa) Parameters Stomata conductance (mmol m-2s-1) Fruit-set Pea-size Véraison Harvest Fruit-set Pea-size Véraison Harvest V1 -0.49 a -0.47 a -0.46 a -0.64 a 291.51 a 343.58 a 256.52 a 410.82 a V2 -0.50 a -0.60 b -0.54 b -0.95 b 240.64 a 289.25 b 174.98 b 379.46 b In column, means followed by different letters were significantly different at P=0.05 using SNK test. Table 3. Main quantitative and qualitative yield parameters of Italia table grape at harvest (average 2010-11). Treatment Bunch weight Berry weight (g) (g) Total Titratable soluble acidity solids (g L-1) (° Brix) pH Yield Total leaf area per vine (kg vine-1) Crop water Leaf area/ productivity yield (m vine ) 2 (kg m-3) (m2 kg-1) -1 V1 720.93 a 7.35 a 17.09 a 5.61 a 3.54 a 24.40 a 20.15 a 17.14 b 0.82 a V2 629.32 b 6.90 b 16.41 b 5.62 a 3.51 a 20.87 b 17.79 b 18.15 a 0.85a In column, means followed by different letters were significantly different at P=0.05 using SNK test. In this research irrigation treatment did not affect the berry physical characteristics at harvest and skin colour berry parameters (Table 4). Table 4. Influence of water regimes on berry physical characteristics and skin berry colour of Italia tale grape (average 2010-11). Treatment Skin firmness (g) Berry removal force (g) Firmess (g) L* (brightness) a* (greenness) b* (yellowness) V1 106.72 a 222.24 a 898.72 a 34.41 a -2.06 a 8.40 a V2 100.33 a 214.97 a 862.96 a 33.90 a -2.12 a 9.14 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. ORAL SESSION 8 Moderately vine water stress (80% of Etc) reduced significantly the vegetative growth as shown by the pruning and the cane weight (Table 5). Table 5. Effect of different watering volumes on the pruning weight of Italia table grape (average 2010-11). Treatment Pruning weight (g) Average cane weight (g) Ravaz Index V1 3540 a 129.52 a 6.89 a V2 2860 b 104.34 b 7.30 a In column, means followed by different letters were significantly different at P=0.05 using SNK test. 7th International Table Grape Symposium 99 Discussion and Significance of the Study According to the preliminary results of this study, the application of a high irrigation volume (V1) have favoured the water status, the canopy development and induced an increase in vegetative and productive growth. ‘Italia’ wellirrigated vines (V1) took more advantage from the highest water supply, in such a way that their higher metabolic activity determined a higher vegetative and productive development. However the irrigation at 80% of ETc appeared to be sufficient to achieve a complete table grape vineyard development under the environmental condition of the Apulia region. By comparing V2 (moderately stressed vines) and V1 (well irrigated vines) the best balance among vegetative growth, grape yield, berry quality and water use in table grape production, was obtained in V2 vines, with the possibility to reduce the irrigation water requirement. In addition, from this study emerges the utility of midday stem water potential and stomata conductance as interesting tools for qualitative evaluation of low deficit and normal irrigation on table grape vines. Acknowledgements The work was supported by the Italian Ministry of Agriculture and Forestry Policy (Bando Agricoltura biologica D.M 24327/7742/09 de 22/10/2009), Project “Tecniche biologiche di produzione e conservazione per la salubrita’ dell’uva da tavola ”, acronimo SAL.U.TA; publication No. 3. References Allen RG, Pereira LS, Raes D and Smith M. 1998. Crop evapotranspiration: guidelines for computing crop water requirements. In: FAO Irrigation and Drainage Paper. FAO (Roma): 15-27. Chaves MM, Santos TP, Souza CR, Ortun MF, Rodrigues ML, Lopes CM, Maroco JP and Pereira JS. 2006. Deficit irrigation in grapevine improves water-use efficiency while controlling vigour and production quality. Annals of Applied Biology 150(2): 237-252. Chonè, X., Van Leeuwen, C., Dubordieu, D. and Gaudillere, J.P., 2001. Stem water potential is a sensitive indicator of grapevine water status. Annals of Botany. 87: 477-483. Ezzahouani, A. and Williams, L.E., 2007. Effect of irrigation amount and preharvest irrigation cutoff date on vine water status and productivity of Danlas grapevines. American Journal of Enology and Viticulture 58(3):330-340. Kliewer WM, and Dookzlian N K. 2005. Leaf area/crop weight ratios of grapevines: influence of fruit composition and wine quality. American Journal of Enology and Viticulture 56: 170-181. Jones G V. 2007. Climate change: observations, projections, and general implications for viticulture and wine production. Proceedings of OIV Congress of Vine and Wine, Zaragoza, Spain April 10-14. Tarricone L, Gentilesco G, Ciccarese A,Stellacci AM and Rubino P. (2012). Irrigation strategy affects quantitative and qualitative vine performance of ‘Italia’ table grape. Acta Horticulturae 931: 203-209. Williams, L.E., Grimes, D.W. and Phene, C.J. 2010. The effects of applied water at various fractions of measured evapotranspiration on reproductive growth and water productivity of ‘Thompson Seedless’ grapevines. Irrig. Sci. 28(3):233-243. Willer H. 2011. Organic agriculture worldwide, key results from the global survey on organic agriculture 2011. FiBL & IFOAM, Survey 2011. ORAL SESSION 8 100 7th International Table Grape Symposium A study on the factors involved with russet stains in Thompson Seedless table grapes H Weksler*, T Kaplunov, Y Zutahy, A Daus and A Lichter Department of Postharvest Science, ARO, The Volcani Center, POB 6, 50250, Bet Dagan, Israel. *Corresponding Author: Tel: 972 2 9910781, Email: [email protected] Background and Aims Sporadic events of russet stains in Thompson Seedless have for years been observed in the Lachish region in Israel but it was not until 2010 and 2011 that this issue has become a threat to Thompson growers with damages soaring up to 50% in some plots in this region. The damage was mainly superficial and characterised by elongated parallel and/or concentric brown stains which significantly reduced the value of the fruit to below commercial value, even at the less demanding domestic market. Viticulturists from various countries did not have conclusive idea as to the cause of the symptoms but berry size, weather conditions and pesticides were noted as possible factors. These severe damages triggered a study aimed at understanding the factors involved with the development of those stains and at developing effective control measures. Experimental Procedures and Results First symptoms were usually seen in early July after véraison and symptoms escalated during fruit ripening. Microscopic observations revealed a micro-crack at the center of each blemish (i.e. a superficial crack that did not transverse the flesh). This finding led to hypothesising that the formation of a micro-crack occurs first and is conditional to the development of the rust stain. A survey conducted at over 100 Thompson plots in the affected region showed correlation between the level of the stains and poor air movement and/or light penetration throughout the plot. Another important observation was that more damage was incurred in the back and bottom part of the cluster. This pattern led to the hypothesis that rust stains were caused by foliar sprays which are slower to dry in the back part of the cluster and in vineyards with slower air movement or light penetration. Dipping berries off the vine in solutions of various commercial formulations of fungicides and insecticides showed enhanced macro-cracking by some commercial compounds, suggesting that they have the potential to cause damage to the peel upon prolonged exposure. Spraying clusters with various commercial formulations of pesticides enhanced rust stain formation which was also caused, to a lower extent, by the water control. Other results showed positive correlation of rust stains with berry firmness and TSS level. Berries with rust stains suffered higher postharvest weight loss and finally, spatial distribution of stained clusters at the vineyard revealed a non-random pattern. Discussion and Significance of the Study ORAL SESSION 8 The results suggest that some commercial formulations of pesticides applied between véraison and maturity, may induce micro cracking and subsequently russet stains. Possible ways to reduce the risk may be reduction of pesticide application at that time. This study reveals potential causes for a significant viticultural problem of table grapes and suggests directions which may control it. Acknowledgement The research was funded by TALI GRAPES in Israel. We thank Mr Guy Rozenfeld from Moshav Lachish for his initiatives and assistance. We also thank all the dedicated growers who contributed their vineyards to the study and in particular to Udi Rosenfeld, Asaf Arad, Dani Barel and Mordechay Vaknin. References Fichette T. 2013. Primary cause of grape cracking still elusive. Western Farm Press Exclusive insight P.1 Lee CY and Jaworski AW. 1988. Phenolics and browning potential of white grapes in New York. American Journal of Enology and Viticulture 39(4): 337-340. Swift JG, May P and Lawton EA. 1974. Concentric cracking of table grapes. Vitis 13: 30-35. 7th International Table Grape Symposium 101 Causes and prevention of Thompson Seedless berry collapse Peter Clingeleffer1,2,*, Davinder Singh2, Michael Treeby2,3 and Kristen Pitt4 CSIRO Agriculture, PMB 2 Glen Osmond, SA 5065 Formerly CSIRO Plant Industry, Merbein, Victoria 3505 3 Primary Industries Science and Research, New South Wales, Dareton, New South Wales 2717 4 DEPI, Macleod, Victoria. 3085 *Corresponding author: Tel: (08) 83038721, Email: [email protected] 1 2 Background and Aims In Australia, Thompson Seedless is the most popular table grape variety on the domestic market and a significant export variety. However, incidences of berry collapse in 3 seasons (1997-98, 2000-01 and 2007-08) resulted in significant crop and financial losses to fresh grape producers. Berry collapse in Thompson Seedless becomes visually obvious around véraison (berry softening). The visual symptoms in the severe seasons generally involve development of striated necrotic (dead) tissue in the berry skin, berry discolouration and collapse, predominantly at the distal end of the berry, with an apparent loss of moisture from the berry (Figure 1.) Figure1. Bunch showing typical berry collapse at harvest (left). Berry showing striations associated with necrotic tissue which occurs around véraison and is the first sign of a problem (right). GA sprays and cincturing are used by the table grape industry to increase berry size of seedless varieties because of consumer demand for larger berries. Interrogation of the historical weather data suggested that most of the problem was associated with heat stress during the time when GA is applied for berry sizing. On average, maximum temperatures were 5-10°C higher during late November in the 3 seasons when widespread berry collapse was observed, compared to other seasons when there was no or very low incidences of berry collapse. A series of studies and trials were conducted over three seasons to investigate the factors contributing to berry collapse of Thompson Seedless and to develop management options to ameliorate the effect of such factors. Experimental Procedure and Results ORAL SESSION 8 Extensive microscopy of the affected tissue showed that berry collapse symptoms were the result of cell death and loss of internal structure in the collapsed part of the berry (Figure 2). It was also noted that berries without any collapse symptoms such as water berries (i.e. berries with a soft tip at the distal end) and berries with vertical brown striations also showed internal cell death. Striated berries lost water at more than twice the rate of berries without symptoms and had high total soluble solids (TSS or °Brix) suggesting that loss of water through the cracks in the cuticle (Figure 3) is associated with berry cell death. Figure 2. Microscopic symptoms of (a) healthy, (b) collapsed and (c) striated berries of Thompson Seedless stained with fluorescein diacetate. 102 7th International Table Grape Symposium e 2. Microscopic symptoms of (a) healthy, (b) collapsed and (c) striated berries of Thompson Seedless ed with fluorescein diacetate. A. Healthy berry B. Collapsed berry Top Bottom Figure 3. Scanning electron microscopy on the top and bottom half of a healthy berry (A) and a berry showing symptoms of berry collapse (B) at X 80 magnification (200m). (C) The cracks in the cuticle (bottom half) of a collapsed berry are e 3. Scanningshown electron microscopy on the i.e topX and bottom half of a healthy berry (A) and a berry showing at higher magnification 160 (200m)(far right). toms of berry collapse (B) at X 80 magnification (200m). (C) The cracks in the cuticle (bottom half) of a studiesmagnification with elevated i.e temperatures and water stress treatments confirmed that the incidence of berry psed berry areGlasshouse shown at higher X 160 (200m)(far right). collapse can be linked to GA treatment and high temperatures during early berry development and that the shouse studiesproblem with elevated temperatures and water stress treatments that the incidence of to maximum is exacerbated by water stress. The results suggestedconfirmed that the ‘trigger point’ with respect between 35°Cand andhigh 40°C. collapse can temperature be linked to isGA treatment temperatures during early berry development and that roblem is exacerbated by water stress. The results suggested that the ‘trigger point’ with respect to Widespread occurrence of berry collapse in Thompson Seedless in the 2007-08 season provided an opportunity mum temperature is between 35°C and to identify ‘best practice’ that40°C. may enable growers to minimise the incidence of berry collapse in future seasons. Notable of vineyard management on properties where berry collapse was minimal in that season included spread occurrence of features berry collapse in Thompson Seedless in the 2007-08 season provided an complete coverage of ground surface by irrigation (e.g. with undervine sprinklers); careful attention to water rtunity to identify ‘best practice’ that may enable growers to minimise the incidence of berry collapse in management to minimise stress during shoot and berry development including a significant application in early e seasons. Notable vineyard managementofonanproperties where collapse was minimalcanopy in springfeatures to fill theof soil profile; maintenance established coverberry crop potentially to reduce temperatures season included complete coverage of ground surface by irrigation (e.g. with undervine sprinklers); and reduce soil water evaporation losses; adoption of large, wide V trellises to reduce soil water evaporation losses ul attention toand water management to minimise andabove berry the development including a temperatures and lower canopy temperature; thestress use ofduring mistersshoot situated canopy to reduce canopy increase humidity highsoil temperature conditions, and of cover plasticcrop vine covers above the vine canopy icant application in early springunder to fill the profile; maintenance of anpositioning established to ensure adequate air circulation and ventilation. A number of products were tested to assess the potential to reduce the incidence of berry collapse in Thompson Seedless. These included the plant hormones, jasmonic acid (JA) and salicylic acid (SA) which are involved in plant defence mechanisms against pathogen attack and hence cell death; putrescine, a natural polyamino acid which has been used to increase fruit size in a number of horticultural crops; and, a reflective, particle film product (Surround®) which has been shown to reduce canopy temperatures and maintain leaf function of grapevines and other horticultural crops under stress. Of these products Surround®, which reduced canopy temperature by 2-3°C, has shown the most promise as it not only reduced early symptoms of berry collapse (i.e. brown striations associated with water stress treatments), but also promoted early ripening associated with early véraison and increased berry weight. The earlier ripening with the Surround treatment could be exploited by the table grape industry to market fruit earlier in the season. ORAL SESSION 8 Figure 3. Vine leaves sprayed with Surround®. 7th International Table Grape Symposium 103 Rootstock and irrigation management trials were also conducted in the 2008-09 season to determine any interaction between rootstock, water stress and berry collapse. Although limited berry collapse occurred during that season due to mild weather conditions, data collected suggest that vines on Schwarzmann rootstock had significantly more berries with soft tip and brown striations as compared to Ramsey rootstock under water stress conditions (Table 1). Cinctured vines on both rootstocks generally had higher incidence of berries that had soft tip and brown striations as compared to uncinctured vines, suggesting a link between rapid growth of the berry and the development of symptoms (Table 1). Table 1. Field trial data showing the effect of rootstock, water stress and cincturing at the time of GA application for sizing on the % of berries with soft tips and brown striations, twenty bunches per treatment were assessed at the time of harvest. Superscripted letters indicate significant differences between the means within columns (P<0.001). Rootstock Ramsey Schwarzmann Irrigation Cincture % berries with soft tip % berries with brown striations Control - 2.0a 7.5a Control + 6.8b 14.8b Stress - 4.5b 13.3b Stress + 14.2e 15.4b Control - c 4.8 16.5c Control + 8.8d 38.8d Stress - 7.3c 19.8c Stress + 17.4f 17.7c Discussion and Significance of the Study Glasshouse trials and field studies have confirmed a link between berry collapse, GA application and high temperature during the early stages of berry development. The problem is exacerbated by water stress, cincturing and some rootstocks (e.g. Schwarzmann compared to Ramsey). Vineyard management practices have been identified which should enable Thompson Seedless growers to minimise losses from berry collapse if high temperatures occur during and subsequent to the period when GA is applied to enhance berry size. Attention should be given to irrigation management to minimise water stress during the critical berry development period. If high temperatures are forecast, growers should consider not cincturing and adjust the timing of GA sizing sprays. Application of particle films such as Surround®, to reduce canopy and fruit temperature, shows promise as a technique to reduce Thompson Seedless berry collapse. Acknowledgments The authors acknowledge the input of members of the Murray Valley Table Grape Growers’ Council, the Australian Table Grape Growers’ Association (ATGA) and thank the participating growers in the conduct of field trials. The project was supported by Horticulture Australia, CSIRO and DEPI-Victoria. Tori Nguyen, Joel Beloy and Patrick Ellis provided valuable technical support. References Singh DP, Treeby M, Pitt K and Clingeleffer P. 2009. Thompson Seedless berry collapse. 12th Australian Table Grape Technical Conference Proceedings. 16-17 September, 2009. ORAL SESSION 8 Singh DP, Treeby M, Nguyen T, Beloy J and Clingeleffer P. 2009. Thompson Seedless berry collapse. The Vine, 5(3): 34-5. Singh DP, Treeby M, Nguyen T, Pitt K and Clingeleffer P. 2008. Thompson Seedless berry collapse- symptoms and causes. The Vine, 4(5): 20-1. Treeby MT, Krstic MP, Mason H, Storey R and Clingeleffer PR. 2004. Thompson Seedless berry collapse: scoping study. Final report, Horticulture Australia. Pitt K, Krstic MP, Kourmouzis T, Clingeleffer PR, Storey R and Treeby MT. 2003. Table grape berry collapse. In: Proceedings of the 6th Australian Table Grape Growers Technical Conference, Mildura, Vic : Murray Valley Table Grape Growers Council. 2003, 91-5 Singh DP, Treeby M, Pitt K and Clingeleffer P. 2010. Causes and prevention of tablegrape berry collapse. Final report to Horticulture Australia (TG04001). 104 7th International Table Grape Symposium The use of autofluorescence and imaging for phenological analysis of table grapes A Lichter1*, T Kaplunov1, Y Zutchi1, A Daus1, I Maoz1, A Bahar2, E Raban3 and S Lurie1 Department of Postharvest Science, ARO, The Volcani Center, POB 6, 50250, Bet Dagan, Israel Selcuk University, Silifke Tasucu Vocational School, Mersin, Turkey 3 Extension Service, The Ministry of Agriculture, Bet Dagan, Israel. *Corresponding author: Tel: 972 3 9683684, Email: [email protected] 1 2 Background and Aims Table grapes are exposed to many manipulations which affect the quality of the berries, such as application of plant growth regulators (PGRs) and pesticides, girdling and other innovative treatments. Subjective evaluation of the effect of these treatments is common but is prone to inconsistencies. During ripening the chlorophyll content decreases, there are changes in the flavonoid content of the berries as well as many other compounds. These changes affect the spectral properties of the berries which are expressed in its autofluoresence emission. Experimental Procedures and Results The kinetics of ripening of ‘Thompson Seedless’ were followed by the autofluorescence profiles using the Multiplex 3 instrument (Force A, Orsay, France). This portable instrument uses four excitation sources and three emission channels to calculate the ratios between different signals, thus nullifying the effect of the structural complexity of the cluster. The red to far red emission (SFR_R), which relates to chlorophyll content, declined during ripening in inverse correlation to (R2=0.97) to the increase in total soluble solids. Application of the cytokinin CPPU during fruit set had a pronounced effect on the FLAV ratio which correlates to flavonoid content of the berry. The tannin determination method of protein precipitation confirmed that the CPPU treatment increased the content of soluble tannins which affect the astringency of the berries. The ANTH ratio which correlates to anthocyanins was capable of quantifying the effect of ABA on the colour of ‘Flame’ and ‘Crimson’ grapes in full agreement to the laborious chemical analysis. Rachis quality is another important parameter of table grapes after storage which is not easy to measure. By using image analysis and autofluoresence it was shown that cytokinin and gibberellin in concentrations which are practiced in the vineyard (2 and 20 ppm, respectively) did not improve rachis quality in four major grape cultivars (‘Mystery’, ‘Superior’, ‘Crimson’ and ‘Red Globe’). On the other hand, packaging which reduces water loss had a significant effect on rachis quality. The kinetics of rachis browning before and after cold storage were used to determine half-browning values which can assist in predicting the shelf life of table grapes. Discussion and Significance of the Study The results suggest that ripening can be efficiently followed by its autofluorescence properties and that horticultural treatments that affect ripening can be robustly measured. It is shown for the first time that cytokinin can alter the flavour of the berries by increasing their tannin content. It is also shown that unlike the common thinking PGRs do not necessarily improve rachis appearance. This study demonstrates the value of objective means to phenotype table grapes in the vineyard and after storage. Acknowledgement ORAL SESSION 8 The research was partly funded by the Chief Scientist – The Ministry of Agriculture, and by the Table Grape Board – The Plant Council, Israel. We wish to thank Guy Rosenfeld from Moshav Lachis for his initiatives and assistance. We thank grape growers which contributed their vineyards to the study and in particular to Yuval Sadan and Asaf Arad. We also wish to thank Dr Victor Alchanatis and his group at the Agricultural Engineering of ARO for the image analysis. References Bahar A, Kaplunov T, Zutahy Y, Daus A, Lurie S and Lichter A. 2012. Auto-fluorescence for analysis of ripening in Thompson Seedless and colour in Crimson Seedless table grapes. Australian Journal of Grape and Wine Research 18:353-9. Raban E, Kaplunov T, Zutahy Y, Daus A, Alchanatis V, Ostrovsky V, Lurie S and Lichter A. 2013. Rachis browning in four table grape cultivars as affected by growth regulators or packaging. Postharvest Biology and Technology 84: 88-95. 7th International Table Grape Symposium 105 Satellite-based assessments of irrigation water use by table grapes grown in the Robinvale district of SE Australia D Whitfield*, M Abuzar, A McAllister, M O’Connell, K Sheffield and L McClymont Department of Environment and Primary Industries, Victoria, Ferguson Rd, Tatura, VIC 3616, Australia Background and Aims Farm/region scale assessments of irrigation water use efficiency have been undertaken by the Victorian Government over several decades. Studies have included intensive farm-based appraisals focussed on irrigation methods, water supply and crop yields, and an alternative satellite-based approach which targets the ability of irrigators to match irrigation water supply to crop demand for water (Whitfield et al., 2011). The satellite approach employs measures of irrigation water demand calculated from satellite measures of the area and vegetation cover (Normalised Difference Vegetation Index; NDVI) of irrigated fields, crop information (from contemporary land use maps), and field/farm-specific estimates of crop/pasture water use (evapotranspiration; ET) based on values of the crop coefficient, Kc, that relate crop evaporation rates to NDVI (Whitfield 2011), and surface measures of reference crop ET (ETr; Allen 2006) derived from local SILO weather data. The satellite approach employs estimates of daily ET in soil water balance calculations to estimate the amounts of irrigation water needed to match crop water supply (irrigation + rainfall) and crop water requirement during the irrigation season. The major sources of supplementary water for irrigation in the Sunraysia district are provided by surface water supplies sourced from the River Murray. This paper compares satellite-based measures of the irrigation water requirement of table grape with official records of surface irrigation water supply (Victorian Water Register; www.waterregister.vic.gov.au) to farms in the Robinvale district of SE Australia in season 2011/12. Experimental Procedure The study addressed irrigation farms in the range of longitude, 142.563° to 143.147°, and latitude, 34.580°S to 34.788°S (Figure 1) for the period, July 1, 2011, - June 30, 2012. Field-scale irrigated land use data for the district were acquired from SunRise21 (www.sunrise21.org.au). An ASTER satellite image, acquired on 6 Jan 2012, was analysed for field-scale measures of NDVI and field area. ORAL SESSION 8 Figure 1: Location of irrigated table grape farms in the Robinvale district of northern Victoria. Satellite-based estimates of irrigation water requirement Water use analyses were confined to mono-cultural farms engaged exclusively in the production of table grapes in order to minimise complexities in the interpretation of data associated with a mix of crops on farms. Farm water supply and irrigation demand were described in terms of supply and demand hydrographs, respectively. Supply hydrographs described cumulative irrigation water supply (Victorian Water Register) associated with water use licenses (wul’s) in the period, 1 July, 2011 to 30 June, 2012. Demand hydrographs described cumulative farm demand for irrigation water as determined by weather and the number and area of irrigated table grapes grown on a farm. Farm-scale irrigation demand hydrographs were formulated on the basis of the area of each field, and associated field-scale estimates of irrigation water requirement (IWR). 106 7th International Table Grape Symposium Field-specific estimates of IWR calculated using satellite-dependent crop coefficients (Kc) derived from the following equation (DPI 2010, 2011): Kc = 1.33 NDVI + 0.167 ; 0.1 < NDVI < 0.63 (1) Kc estimates were subject to the condition, 0.05 ≤ Kc ≤ 1.0. Eq. 1 was derived from satellite-based estimates of crop ET made using the METRIC algorithm (Allen et al 2007; Whitfield et al 2011). Estimates of the irrigation water requirement of each field were made by standard soil water balance estimates of the amounts of water needed to maintain root zone soil water content in an ideal, stress-free condition. It was assumed that optimal growth and irrigation conditions were provided by pressurised irrigation systems operated at a root zone soil water deficit of 25 mm. Soil water balance estimates of crop- and field-specific irrigation water requirement were calculated on the basis of daily NDVI-dependent crop evapotranspiration estimates made using “tall” crop reference ET (ETr): ET = Kc ETr (2) Here, ETr was ‘tall’ crop reference ET, computed using SILO ‘patched point’ meteorological data for Robinvale (https://www.longpaddock.qld.gov.au/silo) by standardised methods described by Allen (2006). Thus, irrigation was applied in weather and crop-dependent applications of approximately 25mm whenever ET activity by crops combined with lack of rainfall to generate a root zone soil water deficit of 25mm. Excess effective rainfall that exceeded the root zone soil water storage capacity (25mm) resulted in rainfall losses as run off and/or deep drainage. Results 87 district farms were devoted solely to table grape production in the study area. Figure 2 shows a large variation in the overall seasonal farm water supply: crop demand ratio, which ranged from < 1.0 on approximately 10% of farms to a median value of approximately 1.75, and to a maximum of approximately 12 on two farms. Figure 2: Frequency distribution of the ratio of farm-scale seasonal irrigation water supply to irrigation water requirement for table grape farms in the Robinvale district, 2011/12. 7th International Table Grape Symposium ORAL SESSION 8 Figure 3 shows that the temporal irrigation regime of several irrigators closely approximated trends in farm-scale satellite-based irrigation water requirement, whereas temporal trends in irrigators where water supply exceeded crop water requirements to be strongly correlated with seasonal crop needs, but irrigation supply strongly diverged from crop water requirements by varying mounts depending on farm (Figure 4). 107 (a) (b) Figure 3: Water supply hydrograph (•--•) and irrigation water requirement (•--•) of table grapes on example farms where water supply approximated irrigation water demand. Solid lines describe the upper (−−) and lower (−−) bounds on irrigation water requirement subject to assumptions that all crops on a farm were described by maximum and minimum observed table grape values of NDVI seen in the Robinvale district. (b) (a) Figure 4: Water supply hydrograph (•--•) and irrigation water requirement (•--•) of table grapes grown on example farms where water supply digressed from irrigation water demand. Solid lines describe the upper (−−) and lower (−−) bounds on irrigation water requirement subject to assumptions that all crops on a farm were described by maximum and minimum observed table grape values of NDVI seen in the Robinvale district. Discussion and Significance of Study Analyses showed that irrigation water use in table grapes commonly exceeded farm-specific irrigation water requirements. Time trends in farm-scale water use on farms were generally consistent with satellite-based water balance estimates of irrigation water requirement. Irrigators consequently appeared to apply more irrigation than was required for crop purposes. An undersupply of irrigation water was seen in a minority of cases. The analysis therefore suggests that irrigators intentionally used more irrigation water than needed to meet crop water requirements, potentially as a means of evaporative cooling for premium product quality. Although further investigations are needed to quantify and satisfy the cooling needs of table grape crops in the Robinvale district, these data suggest that satellites potentially provide an important affordable comprehensive data source for the management and appraisal of irrigation water use for table grapes grown in SE Australia. Acknowledgements ORAL SESSION 8 The authors acknowledge support for the foundation project “Satellite-based measurement, monitoring and reporting systems for improved irrigation water management in SE Australia”, provided by the Raising National Water Standards program of the National Water Commission, Australia, and the support of the Department of Environment and Primary Industries in the present study. References Allen RG, Pruit WO, Wright, JL, Howell TA, Ventura F, Snyder R, Itenfisu D, Steduto P, Berengena J, Baselga Yrisarry J, Smith M, Pereira LS, Raes D, Perrier A, Alves I, Walter I and Elliott R. 2006. A recommendation on standardized surface resistance for hourly calculation of reference ETo by the FAO56 Penman-Monteith method. Agricultural Water Management 81:1-21. Allen RG, Tasumi M and Trezza R. 2007. Satellite-based energy balance for mapping evapotranspiration with internalized calibration (METRIC) – model. Journal of Irrigation and Drainage Engineering 133: 380-394. DPI (2010) Final report: Measurement, Monitoring and Reporting Systems for Improved Management of Farm and Regional Water Resources in Australia. FFSR Res. Div. DPI, Vic. DPI. 2011. Technical Report: Water use of irrigated crops in the Sunraysia Irrigation Region. FFSR Res. Div. DPI, Vic. Whitfield DM, O’Connell MG, McAllister A, McClymont L, Abuzar M and Sheffield K. 2011. SEBAL-METRIC Estimates Of Crop Water Requirement In Horticultural Crops Grown In SE Australia. Acta Horticulturae 922:141-148. 108 7th International Table Grape Symposium Session 9. Postharvest technologies Sulfur dioxide in the berry: metabolism, inducible defences and insights MJ Considine*1,2,3, CS Gordon2 and CH Foyer1,3 School of Plant Biology, University of Western Australia, M084/35 Stirling Hwy, Crawley, WA, 6009 Department of Agriculture and Food Western Australia, 3 Baron-Hay Crt, South Perth, WA, 6151 3 Centre for Plant Sciences, University of Leeds, Leeds, West Yorkshire, UK, LS2 9JT *Corresponding author: Tel. +618 6488 1783, Email. [email protected] 1 2 Background and Aims Elemental sulfur (S0) and sulfur dioxide (SO2) are ubiquitous in the grape and wine industries. They are cheap and effective against the battery of mites and pathogens that infect or otherwise damage berry quality. Nonetheless, industry remains aware that environmental and health concerns will eventually prompt further restrictions or a complete ban, forcing adoption of more costly or less effective alternatives. In the vineyard, S0 is chemically equivalent to SO2, as it will rapidly oxidise. SO2 (+ sulfites HSO3-/ SO32- in solution) are the active forms against pathogens, disrupting the membrane integrity of pathogens and binding and disrupting protein and enzyme function (Avis et al., 2007). Industry perspective centres on SO2/ sulfite residues on the berry, which may provoke respiratory conditions in consumers or affect sensory quality (more-so in winemaking). While it remains commonly assumed that SO2/ sulfites cannot penetrate the cuticle of the berry, our data shows otherwise, and the metabolic consequences may be quite major, and yet perhaps beneficial. Our earlier studies showed that SO2, as commercially applied to table grapes in storage, induces marked changes in antioxidant properties of the fruit (Considine et al., 2009). Further investigation showed that these effects were driven by massive transcriptional reprogramming within the berry during exposure in 21 days’ storage (Giraud et al., 2012). The transcriptional patterns showed broad perturbation to oxidative defences, consistent with a substantial abiotic stress. Not surprisingly, components of the sulfur metabolic pathway were induced, as well as sequestration and detoxification components, for example several members of the Glutathione-S-Transferase (GST) family of genes. The current investigation extends these studies to further metabolic investigation, particularly in relation to sulfur metabolism and functions associated with GSTs, including anthocyanin transport and storage, which is highly relevant to the grape and wine industries. These studies are designed to improve the awareness of inducible defences in the grape berry in order to guide future research into suitable safe alternatives. It will also give perspective to sulfite exposure during the grape crush process of winemaking. At the time of this submission, data were still in process, so herein we outline the initial observations and implications for the composition, quality and vitality of grape berries. All data will be presented at the 7ITGS symposium, and authors can be contacted to access a copy once presented. Experimental Procedure and Results All reagents and chemicals were purchased from Sigma, Australia, unless otherwise stated. Table grapes (var. Crimson Seedless) were harvested at commercial maturity from a vineyard in the Swan Valley of WA and immediately transported to the laboratory for packaging. Ten 1kg lots of intact bunches, with any damaged fruit discarded, were packaged into cherry boxes, and transferred to 4°C storage overnight, prior to subjecting them to treatments. To 5 1kg boxes, a 1kg-equivalent strip of SO2-pad was applied (Uvasys, Grapetek, South Africa), while the remaining 5 boxes were left untreated. All fruit remained at 4°C storage for 21 days, thereafter individual berries were randomly selected from each replicate box. 7th International Table Grape Symposium ORAL SESSION 9 Four intact berries (minus pedicel) were pooled per replicate and snap-frozen in liquid nitrogen and stored at -80°C until required. The skin of a further four berries (minus pedicel) per replicate was carefully peeled with the use of a scalpel, while the berry was held in nitrogen vapour to prevent oxygen exposure, and pooled, snap-frozen in liquid nitrogen and stored at -80°C until required. The corresponding four skinless berries were pooled per replicate, snap frozen and stored at -80°C until required. Additional intact berries were allowed to equilibrate to room temperature before assaying respiration rates using a LiCOR 6400XT infrared gas analyser, equipped with an Insect Rd chamber, according to manufacturers’ instructions. 109 Total glutathione (reduced GSH) was quantified in skin and skinless berries by HPLC after derivatisation with monobromobimane (MBB) as previously reported, with minor modifications (Queval and Noctor, 2007). In brief, for each biological replicate, frozen samples were homogenised in a mortar and pestle under liquid nitrogen, from which a subsample of c. 50mg (known FW) was taken to a clean mortar and pestle containing liquid nitrogen and 2mL 0.2N HCl. After homogenisation, the sample was allowed to liquefy, transferred to a 1.5mL microfuge tube and centrifuged at 12,000g, 1min, 4°C. A 100mL aliquot of supernatant was diluted 1:1 with 0.2N HCl, 114L sodium borate pH9.5 and 20L 10mM dithiothreitol were added, vortexed and allowed to incubate at room temperature for 30 min. Twenty microlitres 30mM MBB was added, vortexed and incubated at room temperature for 15 min Zoe, having trouble with this graph. Can you please change the legend so it reads in the dark. Finally, 660L 10% (v/v) acetic acid was added, vortexed and placed on the carousel for HPLC analysis � Flesh SO as reported (Queval 2and Noctor, 2007). Quantification was done with an authentic standard. Amino acids were � onFlesh Control analysed the same extract as for total glutathione but using an AccQ-Tag Ultra Derivatization Kit (Waters, � according Skin SO2 to manufacturers’ instructions. Anthocyanins were quantified on separate acid extracts exactly Australia), � Skin Control (Bondonno et al., 2012). as reported previously Also need to put labels on graph A, B, C, D, E !"#$%#&'()"#*+#,"-.,/*01234* Trends in the data indicate quantitative and qualitative effects of SO2 on the amino acid concentration in both and and a titleskin for (Figure the X axis should say Amino acid of change were similar between the two tissues. There berries 1).which The direction and magnitude wereand noplace exceptional effects on the thiol-containing acids, andbe cysteine, although the latter was an asterix in the CYS column in graph C amino where the barsmethionine would normally indetectable. A &!"!# %$"!# Flesh SO2 '%#()&# !".# Skin SO2 '%#',&# !"+# Skin Control *+#',&# %!"!# B %"!# Flesh Control *+#()&# !"-# $"!# !"&# !"!# !"!# !"#$%#&'()"#*+#,"-.,/*01234* Amino acid C %"!# Amino acid !"$# D %!"!# !".# !"-# ."!# !"+# !"/# +"!# !"-# !"&# -"!# !"&# !"%# &"!# !"!# !"!# !"!# Amino acid Amino acid E Amino acid Figure 1. Amino acid concentrations in flesh and skin of SO2-treated or untreated controls after 21 days’ storage at -1 untreatedburst controls after mg.kg 21 days’ Figure 1. berries Amino acid and skin pad, of SOproviding 2-treated or 2-4°C. Intact wereconcentrations treated with a in SOflesh -generating a transient of >100 SO2 followed by 2 -1 -generating pad, providing a transient burst of storage at 2-4°C. Intact berries were treated with a SO 2 sustained release of 2-3mg.kg . Amino acids are plotted according to biosynthetic group: A. Glutamate>100 family (including -1 SO followed by sustained release of 2-3mg.kg-1. Amino acids are plotted according to biosynthetic mg.kgwhich 2 was not resolvable from Glutamine); B. Aspartate family; C. Serine family (including Asparagine, which Histidine, group: A. Glutamate (including Histidine, which not resolvable fromstatistical Glutamine); B. Aspartate was not resolvable from family Serine); D. Aromatic family, and;was E. GABA and NH3. No comparisons had been made at family; C. Serine family (including Asparagine, which was not resolvable from Serine); D. Aromatic the time of submission. Data represent 5 biological replicates per treatment condition. * Cysteine wasfamily, not detectable. ORAL SESSION 9 and; E. GABA and NH3. No statistical comparisons had been made at the time of submission. Data represent 5 biological replicates per treatment condition. * Cysteine waswith not detectable. Total glutathione was expected to increase under treatment SO2, and we were unable to resolve the relative oxidised and reduced fractions. Although trends indicate that total glutathione is moderately increased under SO2 treatment, the effect is unlikely to be statistically significant (Figure 2). 110 111 7th International Table Grape Symposium Flesh Skin Figure 2. Total reduced glutathione (GSH) of flesh and skin of SO2-treated or untreated control grape berries after 21 days’ storage at 2-4°C. No statistical comparisons had been made at the time of submission. Data represent 5 biological replicates per treatment condition. Data assessing the effects of SO2 treatment on anthocyanins and flavonoids were not complete at the time of submission, but will be presented at the conference. In addition, transcript data will be re-interpreted from Girault et al. (2012) for the presentation. Discussion and Significance of the Study The widespread reliance on elemental sulfur, sulfur dioxide and other sulfurous compounds in grape and wine industries warrants research into the metabolic effects in planta, even beyond the context of food safety. Previous research shows that sulfur dioxide not only enters grape berries but vastly alters gene expression. This study sought to extend that insight with metabolic data, to bridge the gap in knowledge between food safety and food quality, and beyond the speculations that may be made from gene expression data alone. This discussion will review our group’s progress towards this, particularly with respect to polyphenols, thiols and amino acids. It will also present a re-interpretation of published gene expression data. Further discussion will elaborate two perspectives: (i) the opportunity to learn from these insights to develop modified practices or alternatives to SO2, and; (ii) the case for investigating the pathways of elemental sulfur to SO2/ sulfites and subsequent effects on berry and wine quality. Acknowledgements This research was partially supported by an ARC Linkage Project to MC and CG (LP0990355). In addition we are very grateful for the contributions by Ellie-Rose Rogers, Shenton College, Perth, (respiration), Greg Cawthray, UWA Plant Biology (GSH) and Catherine Bondonno, UWA Medicine and Pharmacology (anthocyanins). References Avis TJ, Michaud M, Tweddell RJ. 2007. Role of lipid composition and lipid peroxidation in the sensitivity of fungal plant pathogens to aluminum chloride and sodium metabisulfite. Applied and Environmental Microbiology 73: 28202824. Bondonno CP, Yang X, Croft KD, Considine MJ, Ward NC, Rich L, Puddey IB, Swinny E, Mubarak A, Hodgson JM. 2012. Flavonoid-rich apples and nitrate-rich spinach augment nitric oxide status and improve endothelial function in healthy men and women: a randomised controlled trial. Free Radical Biology and Medicine 52: 95-102. ORAL SESSION 9 Considine MJ, Gordon C, Ching S, Croft KD. 2009. Salicylic acid overrides the effect of methyl jasmonate on the total antioxidant capacity in table grapes. Acta Horticulturae 841: 495-495. Giraud E, Ivanova A, Gordon CS, Whelan J, Considine MJ. 2012. Sulphur dioxide evokes a large scale reprogramming of the grape berry transcriptome associated with oxidative signalling and biotic defence responses. Plant, Cell & Environment 35: 405-417. Queval G, Noctor G. 2007. A plate reader method for the measurement of NAD, NADP, glutathione, and ascorbate in tissue extracts: Application to redox profiling during Arabidopsis rosette development. Analytical Biochemistry 363: 58-69. 7th International Table Grape Symposium 111 VapormateTM application in a commercial chamber for controlling table grapes pests Swaminathan Thalavaisundaram* and Angelo Deltondo Linde Crop Sciences, 10 Julius Avenue, North Ryde NSW 2122 Australia * Corresponding author: Tel: 0061 401718590 Email: [email protected] Background and Aims Australia produces about 120,000 tonne of table grapes each year covering 10,500 hectares of land (ATGA, 2010). The major table grape growing regions in Australia are found in the Sunraysia region and the Murray Valley, close to the Murray River in Victoria; the Riverina in New South Wales; and the south-eastern Queensland. Other growing regions include Carnarvon, the Swan valley and South West of Western Australia, central New South Wales, the Riverland in South Australia and central Northern Territory. The four most popular varieties grown in Australia are Thompson Seedless, Menindee Seedless, Crimson Seedless and Red Globe. Australia exports a significant amount of table grapes to Asian countries each year and this is continuing to grow. However export is affected by the presence of field pests. A fumigant to control field pests without damaging the fruit would be valuable for table grape exports. Studies conducted by the Department of Agriculture and Food, Western Australia (DAFWA) in collaboration with the Australian Table Grape Association and Horticulture Australia have shown that VapormateTM (16.7%wt ethyl formate in carbon dioxide) is very effective in controlling table grape pests whilst not impacting on fruit quality or presenting any major environmental or health risks (De Lima, 2009). Based on this background, a trial was conducted to develop an application method using a commercial fumigation chamber. Experimental Procedure and Results Fumigation was conducted in a commercial chamber at the site of Palm Vineyard Merbein West Victoria to reflect the current practice followed by the producer. The internal volume of the chamber was 90m3.The chamber had preinstalled fumigation application injection line through which VapormateTM was applied. The chamber also had preinstalled gas sampling line and VapormateTM was sampled during treatment. Seven polystyrene cartons containing table grapes (variety Red Globe) were used for the trial. The volume of each carton was 20 litres. The cartons were placed in trolley and kept inside the chamber. The table grapes used for the trial was collected straight from the field. Temperature of the chamber was measured during treatment and it was above 15°C. Field collected table grape pests were used for the trial. They were long tailed mealybug (Pseudococcus longispinus), western flower thrips (Frankliniella occidentalis), two spotted mites (Tetranychus urticae), light brown apple moth (Epiphyas postvittana) and grapevine moth caterpillar (Phalaenoides). The target pests were kept in plastic tubs covered with a sieve lid to prevent insect escape during the trial. The plastic tubs were placed at different locations inside the chamber. After the fumigation treatment, the plastic tubs were collected and checked for live and dead insects. Only adult insects were checked in this study. A full cylinder of liquid VapormateTM was placed on a calibrated weigh scale to record the weight during dosing. The cylinder was connected to an electrically heated vaporiser and the outlet from the vaporiser was connected to the pre-installed distribution pipe work into the chamber. The vaporiser has the capacity to deliver @ 500g per minute. A dose rate of 240g.m-3 for 4 hours was used. This dose rate is registered with Australian Pesticide Veterinary Medicine Authority (APVMA) for table grape pests. A total of 21.60kg of VapormateTM was applied into the chamber. It took ~ 45 minutes to deliver the required dose into the chamber. ORAL SESSION 9 The chamber had two sampling lines (top and middle). The middle sampling line was used to collect the gas from the chamber and the top sampling line was used to recirculate the gas back into the chamber. A G450 Multigas monitor was used to measure ethyl formate and carbon dioxide. It can accommodate up to four sensors for monitoring four different types of gases. The detection limits for ethyl formate are between 0.01% and 5% (by volume) and carbon dioxide 0.01% to 28% (by volume) (accuracy ± 0.1%). The monitor has a powerful diaphragm pump which can draw the gas samples from the container. The VapormateTM dose rate used for this trial was 240g.m-3 which is ~1.24 % by volume of ethyl formate. 112 7th International Table Grape Symposium Ethyl formate and carbon dioxide levels were monitored after application. Both the levels achieved the recommended dose rate (240g.m-3) hence treatment period commenced immediately after application. There was only a slight decline in ethyl formate and carbon dioxide during 4 hours treatment period (Figure 1). This shows that the chamber was well sealed and suited for VapormateTM fumigation. After the end of the treatment period, the chamber doors were opened and the fan was used to ventilate the product. It took 30 minutes to completely ventilate the VapormateTM from the chamber. The safety level was checked using the monitor which indicated that it was safe to enter into the chamber after 30 minutes to collect the table grapes and insects. C oncentration (% by volume) 12 10 8 ETF 6 CO2 4 2 0 12:00 PM 1:00 PM 3:00 PM 4:00 PM 4:30 PM T re a tme nt time Figure 1. Ethyl formate and carbon dioxide concentration inside the chamber during 4 hours treatment period. The producer assessed the phytotoxic effects of VapormateTM on the treated table grapes for a number of weeks and found no adverse effects on fruit quality. Target pests mortality assessment was conducted immediately at the end of the ventilation period. All the target pests were killed immediately after treatment (Table 1) which is similar to previous VapormateTM trials conducted in a 6m (20 ft) shipping container (De Lima, 2009). Table 1. Mortality of table grapes pests after VapormateTM treatment at 240g.m-3 for 4 hours. Target pests Treatment mortality Number of live adult insects Number of dead adult insects Mortality (in %) Long tailed mealy bug 0 6 100 Western flower thrips 0 4 100 Two spotted mites 0 4 100 Grapevine moth caterpillar 0 4 100 Light brown apple moth 0 4 100 Discussion and Significance of the Study The study shows that VapormateTM can be used in a commercial fumigation chamber as a potential biosecurity treatment for table grapes exported to Asian countries. Acknowledgements We thank the table grape grower John Argiro Palm vineyards for providing his fumigation facility and doing phytotoxic assessment. ORAL SESSION 9 References: ATGA, 2010. Australian Grapes: Varieties and Regions, Australian Table Grape Association Inc., viewed 30 September 2013 http://www.atga.com.au/varieties-and-regions/ De Lima, F. 2009 Fumigation of table grapes using ethyl formate+ carbon dioxide as a quarantine treatment. Department of Agriculture and Food Western Australia Table Grapes Report 53p. 7th International Table Grape Symposium 113 New techniques of postharvest application of SO2 on table grapes Eduardo Maldonado Araneda1,*, Katerina Maldonado Cortes1 and Christopher Dixon2 Insumos Frutìcolas INFRUTA SA, Juan de la Fuente 534, Lampa, Santiago, Chile Rìo Blanco Limitada *Corresponding author: Tel: 569 8233 5048, Email: [email protected] 1 2 Background and Aims Control of Botrytis cinérea Pers and other postharvest illnesses of table grapes is seldom a trivial issue for most growers and exporters. The use of sulfur dioxide (SO2) in the form of fumigation in chambers or SO2 generating pads have been a standard practices for many years. Since the invention of the SO2 pads by Dr. Nelson in the late 60’s mostly incremental changes have been made in the design and usage of these devices. The grape industry has seen innovations in terms of materials and manufacturing techniques but very few other alternatives have been explored. SO2 pads have evolved from the very traditional ‘paper pad’ to more sophisticated pads built with different materials and dosages of active ingredient with longer and more stable emissions. The increase of Botrytis, on the other hand, is a recognised phenomenon in some countries. In Chile for example, the increase of Botrytis has forced growers and exporters to expand and diversified phytosanitary measures both pre and postharvest. Four years ago we heard from Don Luvisi at the Symposium in Davis, California referring to the postharvest treatment of table grapes for long storage/transit: “We don’t see alternatives to SO2 in the foreseeable future”. We took note of that and got to work looking for better and more effective ways to deliver SO2 and control Botrytis in table grapes. As we looked into incremental improvements we go back and again to Dr. Nelson teachings. In one of his best works The Grape he describes the use of dual release pads and explains that the two stages of the theses type of pads can be used “one above and one underneath the fruit”. The first part of the pad is what we call a ‘Top’ pad, and the second part is what we call a ‘Bottom’ pad. We then set out to evaluate performance and efficacy of different sizes and types of SO2 pads (cell versus laminated) in top position combined with different sizes and types of pads in bottom position, including laminated single release in different sizes and dual release pads with the fast release impregnated. The main hypothesis to be tested in the study is that in order to improve efficacy, SO2 inside the box must be better distributed in order to control Botrytis while at the same time avoiding bleaching damage and limiting sulfites residues. The specific aim of this study was to determine which combinations of Top/Bottom SO2 pads could deliver better results. Experimental Procedure and Results Given two of the characteristics of the SO2 gas (heavier than air and hydrophilic) it is quite clear that the greater distance between the SO2 pad and the fruit, less SO2 and more decay (gray mold) will tend to develop. We measured the effect of distance in terms of SO2 using only Top SO2 pads and with both Top and Bottom pads (Figure 1). ORAL SESSION 9 Figure 1. SO2 concentration and distribution in the box using only Top SO2 pads and with both Top and Bottom pads. The results are absolutely clear, the combination of Top and Bottom pads brings much better distribution of SO2 across the box. Extrapolating the results of Top/Bottom pads, we also have found that SO2 pads of larger size that provide better coverage (percentage of the top or bottom surface) also help to improve the SO2 distribution inside the box, particularly by reaching the corners. 114 7th International Table Grape Symposium Clearly, the ideal distribution is exactly the same amount of SO2 in every location inside the box. With this idea in mind, we have worked in the last few years in designing and testing new Top/Bottom and pad size combinations of pads that should provide more effective distribution of SO2 across the box and as a result better control of Botrytis while at the same time limiting the possibilities of bleaching. This study includes Unidirectional Cell and Laminated pads. Cell based SO2 pads are made of sodium metabisulfite ‘sandwiched’ in the middle of two or three sheets of paper or plastic using heat sealing to create little cells (or sachets). Laminated pads are made by laminating (enclosing or sealing together) two or three sheets of paper and plastic using adhesive and then sprinkling sodium metabisulfite uniformly between the layers. In this study we also use ‘impregnation’ as an alternative to adhere the active ingredient to one of the sheets. The following experiment consists of comparing efficacy and performance with the following combinations of SO2 pads in boxes of red globe table grapes: Table 1. Experimental treatments and position of SO2 pads. On Top of grapes At the Bottom of the Box T0 PP Cell Pad Dual Release 26x46 None T1 PP Cell Pad Dual Release 26x46 Laminated Pad Single Release 26x46cm T2 PP Cell Pad Dual Release 26x46 Laminated Pad Single Release 33x46cm T3 PP Cell Pad Dual Release 26x46 Impregnated Pad Dual Release 26x46cm T4 PP Cell Pad Dual Release 33x46 None T5 PP Cell Pad Dual Release 33x46 Laminated Pad Single Release 26x46cm T6 PP Cell Pad Dual Release 33x46 Laminated Pad Single Release 33x46cm T7 PP Cell Pad Dual Release 33x46 Impregnated Pad Dual Release 26x46cm T8 PP UK Laminated Pad Dual Release 26x46 None T9 PP UK Laminated Pad Dual Release 26x46 Laminated Pad Single Release 26x46cm T10 PP UK Laminated Pad Dual Release 26x46 Laminated Pad Single Release 33x46cm T11 PP UK Laminated Pad Dual Release 26x46 Impregnated Pad Dual Release 26x46cm T12 PP UK Laminated Pad Dual Release 33x46 None T13 PP UK Laminated Pad Dual Release 33x46 Laminated Pad Single Release 26x46cm T14 PP UK Laminated Pad Dual Release 33x46 Laminated Pad Single Release 33x46cm T15 PP UK Laminated Pad Dual Release 33x46 Impregnated Pad Single Release 26x46cm The size of the box is 50x40x12cm is made of wood and contains 8.2 kilograms of Red Globe table grapes. All treatments use 1% ventilation liner. Three boxes per case were prepared and tested. Treatments T0, T4, T8 and T12 correspond to boxes using only Top SO2 pads for Cell and Laminated pads in different sizes (26x46 versus 33x46). Treatments T1, T2, T5, T6, T9, T10, T13 and T14 correspond to boxes using different combinations of Top and Bottom pads for Cell and Laminated pads with different sizes (26x46 versus 33x46). Treatments T3, T7, T11 and T15 correspond to boxes using on Top Cell and Laminated pads in different sizes and Bottom pad that is impregnated. Concentration of SO2 in the Box ORAL SESSION 9 In terms of SO2 concentration, the results shown on this graphic form indicate that the absence of bottom pad is very detrimental to the amount of SO2 that reaches the lower part of the box: almost no SO2 is found at the lower side of the box when no bottom pad is available. The situation is even worse when using laminated pads, since this type of pads tend to generate less SO2 than cell pads. Another clear observation is that cell pads generate substantially more SO2 than laminated pads. Although with some variations, the main conclusion is that the amount of SO2 in the upper and lower and is much closer than with the absence of bottom pads. In other words, the combination of top and bottom pads improves distribution of SO2 along the entire box. 7th International Table Grape Symposium 115 Concentration of SO2 was measured after 100 days of packing. SO2 concentration are shown in yellow for the upper side of the box and green for the lower side in parts per million (ppm) Concentration of SO2 Figure 2. Concentration of SO2 in the box with sulphur pad position. Control of Botrytis cinerea In terms of controlling Botrytis the results indicate clearly that bottom pads help. Boxes without bottom pads show always the worst results in terms of Botrytis. Cell and laminated show similar results in controlling Botrytis but a larger size of the pad improves the performance. Larger pads with better coverage of the box, top and bottom, provide better results in terms of controlling Botrytis. We also see performance improvement when using the impregnation of bottom pads. Three of the four treatments of the series show better results with impregnated bottom pads. Botrytis (red) is measured in terms of number of berries in the box after 100 days. Figure 3. Control of Botrytis cinera with sulphur pad position. Bleaching The results also indicate clearly that bottom pads do not have incidence in bleaching. Directly related with the results of SO2 concentration. Laminated pads produce less bleaching than Cell pads in all categories. Bleaching (blue) is measured in terms of number of berries in the box after 100 days. ORAL SESSION 9 Figure 4. Incidence of bleaching with sulphur pad position. 116 7th International Table Grape Symposium Discussion and Significance of the Study All the pad treatments in the study were still releasing SO2 on day 100th. The implication is that these combinations of top and bottom pads can be used for long term storage, with no fruit damage and effective control of Botrytis. The best combination of top/bottom pads to control Botrytis without bleaching is a larger pad (at least 80% surface coverage) on the internal surface (top or bottom of the box) using a liner with 1% ventilation. The use of bottom pads is highly effective in combination with top pads and do not have major impact on bleaching, which make them attractive for long term storage, particularly in those regions with high occurrence of Botrytis cinerea. We hope that this study and its results will help the table grape industry to improve control of Botrytis and deliver better fruit. Acknowledgements This study was fully supported and financed by INFRUTA S.A., a manufacturer of SO2 pads, and Río Blanco Ltda. the largest exporter of table grapes from Chile. We would like to acknowledge specially the contributions from Mr. Christopher Dixon, Quality Control Manager from Río Blanco Ltda. References Nelson, KE. Extracts from The Grape. No date availble. Luvisi, DA. 2010.California’s Table Grape Industry: A Historical Perspective, Oral presentation at the 6th International Table Grape Symposium, University of California, UC Davis, California 2010. ORAL SESSION 9 7th International Table Grape Symposium 117 Alternative fumigation and cold treatment disinfestation methods A Jessup1*, J Golding1 and F DeLima2 New South Wales Department of Primary Industries, Gosford, NSW, Australia Department of Agriculture, Western Australia, South Perth, WA, Australia *Corresponding author: Tel: +61 2 43481965, Email: [email protected] 1 2 Background and Aims In order to achieve importer approval to export our fresh horticultural products we have to convince importers that our product is free from certain pests and diseases that are regulated by the importing country. There is a number of postharvest disinfestation treatments used internationally to provide quarantine security against pest fruit flies and other arthropod pests such as light brown apple moth, scale insects and spiders. Some of these treatments take many days to complete and some may cause damage to the product rendering it unsalable or subject to price reduction impacting adversely on future exports. Recently some popular disinfestation options, and the fumigant methyl bromide, have been banned (dimethoate and fenthion), or restricted in use (methyl bromide), due to public health and environment concerns. These issues have eroded Australia’s capability to export fresh table grapes, among other fresh horticultural products, both domestically and internationally. Researchers in NSW Department of Primary Industries and Department of Agriculture and Food Western Australia have been developing workable postharvest treatment options for table grapes where fruit flies and other pests are of quarantine concern to the importer. We have been looking at streamlining cold storage treatments and improving the efficacy of ethyl formate fumigations for the pest fruit flies, Mediterranean fruit fly and Queensland fruit fly as well as light brown apple moth (this last carried out by DAFWA). In addition to the above work there have been developments in Australia on other postharvest treatments such as irradiation, low dose fumigation and low pressure disinfestation. Experimental Procedure In all experiments carried out to develop new quarantine treatments against pests such as Queensland fruit fly (Bactrocera tryoni, Froggatt), Mediterranean fruit fly (Ceratitis capitata, Wiedemann) and light brown apple moth (Epiphyas postvittana, Walker) scientists must follow strict research guidelines. These guidelines differ from market to market. Commonly, the most stringent market requirements are chosen to follow if more than one market is to be addressed by disinfestation research. Typically, the Japanese minimum requirements are followed. This practice has seen market acceptance of our research on a number of fresh horticultural products by Japan as well as others such as New Zealand, Taiwan, Korea, the USA, Thailand, the Philippines, etc based on single batches of research. However we generally need to carry out research on each and every commodity we wish to export separately. There is currently an international call for disinfestation researchers to amalgamate their research on different commodities and pest species into generic postharvest disinfestation approaches for cold storage and heat treatment. A generic approach to irradiation as a quarantine treatment currently exists. The experimental protocol used for market access submissions to Japan and other jurisdictions always follow the process outlined below. If the protocol can not be followed precisely then scientifically valid and authenticated (by research) reasons must be supplied. Results and Discussion Our research (De Lima et al., 2011) has led to international approval for decreased number of days in cold temperatures for table grapes against Queensland fruit fly and Mediterranean fruit fly from the commonly accepted US Department of Agriculture Treatment Manual. Promising progress has been made on fumigation with ethyl formate and carbon dioxide (Vapormate®) against a range of quarantine insect pests in table grapes including light brown apple moth (LBAM) (De Lima, 2010) and cherries and persimmons. ORAL SESSION 9 A submission for approval by Food Standards Australia New Zealand (FSANZ) for the irradiation of table grapes as a quarantine treatment is currently under review by FSANZ (call for public submission due by 9 October 2014). Low concentration experiments are currently being tested by researchers in Queensland Department of Agriculture, Forestry and Fisheries) in stone fruit. These researchers are also evaluating comparative cold storage responses for a range of other pest fruit fly species present in Australia. Researchers in NSW DPI are commencing new work on testing low pressure (hypobaric) as multi-benefit treatments (disinfestation, retardation of storage rots, improvement of shelf life) for fresh vegetables. USDA researchers have just completed studies on fumigating cherries with high purity phosphine using the Horn Diluphos® System with considerable success (no data received yet). 118 7th International Table Grape Symposium Table 1. Basic experimental protocol to support new schedules for export to desirable markets. Step Activity Approx. time frame (week) 1 Complete description of research facilities. 1 2 Complete description of insect colony and its maintenance. 1 3 Description of research protocol set up and agreed on by Commonwealth Department of Agriculture and, sometimes, but not often, by the desired importing country. 4 4 Study the development of the insect in each fruit type/ fruit cultivar desired to be exported – so that the maturation span of each immature life stage can be ascertained. 3 to 5 5 Each immature life stage is tested against a range of sub-lethal and lethal doses of the target treatment. The most treatment tolerant life stage is ascertained as well as the optimum lethal dose. 6 to 12 6 A large scale trial, replicated three times on the most treatment tolerant life stage at the optimal lethal dose is carried out. 6 to 12 7 An export submission is compiled with all information including raw data and detailed temperature records/ fumigation concentrations over time. This submission is sent to the Commonwealth Department of Agriculture for review and tabled at the appropriate Bilateral Quarantine Trade Talks for the desired importing country. 12 to 26 8 If approved by the importing country a verification trial is set up where a semicommercial shipment is treated with test infested fruit in the presence of officials from the desired importing country. 26 to 52 9 Approval and gazettal by both the importing country and Australia. 10 Market access. 1 Table 2. Disinfestation treatments for table grapes. Disinfestation treatment Approval status Cold storage QFF -12d/1°C, 14d/2°C, 14d/3°C (also covers Lesser Queensland fruit fly (Bactrocera neohumeralis) (Lindhout and Cruickshank, 2010) Medfly -16d/1°C, 18d/2°C, 20d/3°C Complete Fumigation Vapormate® (Ethyl formate + CO2) LBAM, red back spider -2h/240g.m3/20°C Mealybugs, thrips – 2h/120g.m3/20°C Also worked at 10°C and 15°C at higher doses Continuing Irradiation Fruit flies -150Gray All other arthropods (except Lepidopteran pupae and adults) -400Gy Insecticidal efficacy – international approval achieved. But we need FSANZ approval for use in Australia and New Zealand – currently under review Acknowledgements We thank the many Technical Assistanmts and Technical Officers who have helped us set up and carry out our experiments in NSWDPI and DAFWA as well as Horticulture Australia Ltd, Australian Table Grape Growers, NSWDPI and DAFWA. References ORAL SESSION 9 De Lima, CPF. 2010. Ethyl Formate + C02 Fumigation of Table Grapes for Light Brown Apple Moth. Proceedings of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions, Orlando, Florida, USA, November 2 to 5, 2010. De Lima, CPF, Jessup AJ, Mansfield ER and Daniels D. 2011. Cold treatment of table grapes infested with Mediterranean fruit fly Ceratitis capitata (Wiedemann) and Queensland fruit fly Bactrocera tryoni (Froggatt) Diptera: Tephritidae. New Zealand Journal of Crop and Horticultural Science 39(2):95-105. Lindhout K and Cruickshank DJ. 2010. Comparative study to determine the relative cold tolerance of Queensland fruit fly (Bactrocera tryoni) and Lesser Queensland fruit fly Bactrocera neohumeralis) eggs and larvae undergoing cold disinfestation in table grapes. Report To Horticulture Australia on funded project. 7th International Table Grape Symposium 119 Predicting rachis browning and quality loss in Vitis vinifera L cv ‘Thompson Seedless’ during cool storage John Lopresti*, Oscar Villalta, Bruce Tomkins and Debra Partington Department of Environment & Primary Industries, Victoria, Australia AgriBio Centre, 5 Ring Road, La Trobe University, Bundoora, VIC. 3083 Background and Aims Table grapes, Vitis Vinifera L. cv ‘Thompson Seedless’, are an important export crop with cool storage period lasting up to ten weeks. Grape bunch visual quality can be significantly reduced by rachis browning, berry shrivel and berry shatter (Crisosto et al., 2001). Browning of the rachis can be the first symptom that limits bunch marketability due to a high susceptibility to water loss (Carvajal-Millan et al., 2001). The cause of variation in the rate of rachis browning between bunches is yet to be determined but rachis morphology has been implicated as a potential factor (Balic et al., 2012). Differences in rachis lateral thickness and pedicel diameter resulting from vineyard practices such as application of Gibberellic acid (GA) and bunch thinning, can alter incidence of berry shatter (Zoffoli et al., 2008), while larger, more lignified and less hydrated rachis may be less susceptible to browning (Gardea et al., 1994). This study investigated rachis browning development in grape bunches during cool storage with and without sodium metabisulphide treatment, as influenced by rachis lateral thickness measured using pedicel diameter. Experimental Procedure and Results ‘Thompson Seedless’ grapes were harvested from six vineyards in the Sunraysia district in Australia. Pedicel diameter was measured on five pedicels randomly chosen over the length of each bunch using a digital caliper, and fruit stored at 0°C and >85% RH for up to 12 weeks. The storage trial was a randomised complete block design with vineyard, storage period and pedicel diameter as factors randomised within each of five replicates of 5 bunches each. Bunches were removed from storage and assessed for rachis browning using visual scoring where: 1=green, 2=pedicel browning, 3=secondary lateral browning, 4=primary and secondary lateral browning and 5=rachis completely brown. In a second trial bunches were treated with sodium metabisulphide (Uvasys® pads - 970g. kg-1 Na2S2O5, dual release), and browning development compared to untreated bunches. Treatment effects and interactions were determined using two-way analysis of variance (ANOVA), and means separation based on least significant difference tests (LSD; α=0.05). A strong positive correlation was found between rachis lateral thickness and pedicel diameter (not shown) and thus pedicel diameter was a good measure of rachis development. Rachis browning score was not significantly different between grape bunches with large and small pedicel diameters after 21 days of cool storage (Figure1). However bunches with larger pedicels had a significantly lower mean rachis browning score after 42 and 63 days of storage at 0°C. ORAL SESSION 9 Figure 1. Effect of pedicel diameter and storage period on mean rachis browning score in grape bunches from six vineyards stored at 0°C. Means followed by different letters are significantly different at P≤0.05. A logistic model fitted to rachis browning scores over the storage period, with pedicel diameter at harvest as an explanatory factor, explained 91% of variation in browning score (Figure 2). It was determined that ten pedicel diameter measurements in ten bunches randomly selected from within a vineyard block will provide a relatively accurate indication of the average pedicel diameter in bunches within that block. 120 7th International Table Grape Symposium 5.0 6 days 19 days 34 days 49 days 69 days 91 days Mean rachis browning score 4.0 3.0 2.0 1.0 2.5 3.0 3.5 4.0 4.5 5.0 Rachis pedicel diameter at harvest (mm) Figure 2. Logistic model fitted to pedicel diameter at harvest and storage period at 0°C to explain rate of rachis browning (r2=91%, P<0.001, n=48; rachis browning = A + C/[1 + e-B(X – M)]). Each data point represents the mean score of 8 bunches from each of 6 vineyards. Bunches treated with sodium metabisulphide had significantly lower rachis browning scores than untreated fruit after 30, 42 and 58 days of storage at 0°C (Figure 3). Differences in browning score between treated and untreated bunches was only significant at 42 days of cool storage when pedicel diameter was accounted for as a covariate. This result suggests that thicker rachis laterals may have a similar effect in reducing the rate of rachis browning as treatment with sodium metabisulphide. Figure 3. Effect of sodium bimetasulphide treatment and storage period on rachis browning in grape bunches stored at 0°C (left). Effect of treatment after rachis browning score was adjusted for differences in pedicel diameter between bunches (right). Browning score adjusted for pedicel diameter using analysis of covariance (CANOVA). Means followed by different letters are significantly different at P≤0.05. ORAL SESSION 9 Discussion and Significance of the Study Grape bunches with thicker rachises as measured by larger pedicel diameter had significantly lower browning scores beyond 21 days of cool storage, indicating that vineyard practices that increase lateral thickness may improve bunch visual quality during cool storage or export. Bunch treatment with sulphur dioxide (SO2) significantly reduced rachis browning during storage. But the rate of browning was usually equivalent between treated and untreated bunches when adjusted for pedicel diameter, suggesting that rachises with thicker laterals remain similarly greener during storage both with and without SO2 treatment. 7th International Table Grape Symposium 121 The effect of storage period and pedicel diameter (ie. lateral thickness) on the rate of rachis browning in grapes during cool storage has been modelled for the first time, and potentially enables prediction of rachis browning during commercial storage and export. This may enable growers and exporters to determine the likelihood of postharvest rachis browning and establish the risk of commercially-significant bunch quality loss for a particular shipment prior to storage or export. References Balic I, Moreno A, Sanhueza D, Huerta C, Orellana A and Defilippi BG. 2012. Molecular and physiological study of postharvest rachis browning of table grape cv Red Globe. Postharvest Biology and Technology 72: 47-56. Carvajal-Millan, E, Carvallo T, Orozco J A, Martinez MA, Tapia I, Guerrero VM, Rascon-Chu A, Llamas J and Gardea AA. 2001. Polyphenol oxidase activity, colour changes, and dehydration in table grape rachis during development and storage as affected by N-(2-chloro-4-pyridyl)-N-phenylurea. Journal of Agricultural and Food Chemistry 49: 946-951. Crisosto C, Smilanick J and Dokoozlian N. 2001. Table grapes suffer water loss, stem browning during cooling delays. California Agriculture 55: 39-42. Gardea, AA, Martinez-Tellez MA, Sanchez Α, Baez M, Siller JH, Gonzalez G, Baez R, Crisosto CH and Criddle RS. 1994. Postharvest weight loss of Flame Seedless clusters. In J. A. Rantz (ed.), Proceedings of the International Symposium on Table Grape Production, June 28–29, 1994: 203–206. Zoffoli JP, Latorre BA and Naranjo P. 2008. Hairline, a postharvest cracking disorder in table grapes induced by sulfur dioxide. Postharvest Biology and Technology 47: 90-97 ORAL SESSION 9 122 7th International Table Grape Symposium Poster Presentations Abstracts THURSDAY 13 NOVEMBER 2014 ID 1 Changes in the table grape industry – challenges for a sulphur dioxide pad manufacturer Caroline Adams* and Alwyn van Jaarsveld Tedmark, Grapetek (Pty) Ltd, 129 Industrial Park, 18 Kinghall Avenue, Epping, Cape Town, South Africa 7460 Background and Aims Postharvest grapes are susceptible to fungal infection even when stored at the optimal temperature of -0.5°C. The most important pathogen of stored Table Grapes is ‘Gray Mould’, commonly referred to as ‘Botrytis’, which is caused by Botrytis cinerea. Sulphur dioxide generating pads were thus developed to facilitate the transportation and postharvest storage of table grapes. Because of concern about sulphite residues, there is ongoing research to find alternatives. However the responsible use of sulphur dioxide remains the only commercially viable method of storing and transporting table grapes. The table grape industry has undergone major changes since the use of sulphur dioxide pads became commonplace, particularly in the last 10 years. We would like to discuss how these changes have influenced and changed our company (Tedmark) and product (Uvasys). Experimental Procedure and Results The key changes that have occurred within the table grape industry which have influenced the use of sulphur dioxide include: • • • • The development of different sulphur dioxide pads. The original pads were sachets of sodium metabisulphite, more recent products have this active component encapsulated in a polymeric matrix. Geographical changes in table grape producing countries. Changes in cultivars. 10 years ago the big movement was from seeded to seedless cultivars. We are now seeing the industry moving towards further cultivar developments, particularly those with thinner skins and more turgidity. Changes in packing and packaging • Field packing • The use of punnets • Loose packaging • Different liners • Demands of supermarkets Discussion and Significance of the Study The last decade has also seen an increasing consumer move towards organic produce and demands for transparency when additives are used. In addition consumers are increasingly expecting year around supply of fresh produce. Regulatory legislation on Sulphite MRLs and food safe products has thus increased worldwide. Accreditations with the appropriate authorities are now being requested. In the poster we will show how complex the industry has become and our research, both completed and in progress, on some of the above topics. Acknowledgements We acknowledge assistance from Johan Fourie and Sybrand van Zyl, Experico, PO Box 422, Idas Valley, Stellenbosch, 7609, South Africa. 123 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 2 Timorex Gold - a new natural bio-fungicide for the control of sour rot complex and grey mould in table grapes JC Arroyo1,*, A Langer2, V Valdivieso2, P Quiroz3 and JL Henriquez4 Stockton Israel Ltd. 17 Ha’Mefalsim St, Petach Tikva 4951447, Israel Viticultura y Fruticultura Asociados. Carmen Sylva 2331 Dpt 404, Providencia, Santiago, Chile 3 Consulting Agronomy Ing. S.A.C, Jr. General Varela 548 Dpt. 505, Breña, Lima, Perú 4 Fac. Cs. Agronómicas, Universidad De Chile, Santa Rosa 11.315, Casilla 1004, La Pintana, Santiago, Chile * Corresponding author: Tel: + 56 9 8900 3042, Email: [email protected] 1 2 Background and Aims Pre and postharvest diseases can limit table grape production (Vitis vinifera L.). Grey mould (Botrytis cinerea) is considered to be the most important disease that impacts on fruit quality at the postharvest stage. In addition, the sour rot complex associated with Aspergillus niger, Cladosporium herbarum, Penicillium expansum, Rhizopus stolonifer and Acetobacter sp. may also cause problems. Both diseases generate loss in quality and reduce the shelf life of table grapes, so use of fungicides in an appropriate way is critical to achieve a high quality table grape product. However, issues of residues and concerns with the loss of efficacy due their specific site of action, reported for most of the specific fungicides for the control of berry rots, must also be considered. As a consequence, there is a need for the introduction of new fungicides with different modes of action and a lower risk of resistance development. Timorex Gold (TG) is a new natural bio-fungicide based on the extract of Melaleuca alternifolia which contains 23.8% of the active ingredient. It has a new and unique mode of action against a broad spectrum of plant pathogenic fungi due to their multisite activity. TG has been found to be effective against different disease complexes in various crops. For table grapes it has been evaluated against grey mould and the sour rot complex. Experimental Procedure and Results Trials performed in Chile and Peru from 2011 until 2014 revealed that spraying TG at application rates of 1.5 - 2.0L. ha-1 controlled grey mould and the sour rot complex on berries, and was as effective as chemical and biological fungicides when applied at 7-14 days intervals. The higher dose of 2.0L.ha-1 reduced activity on post-infection lesions on the table grape berries. The first two trials in Chile were performed in Los Andes, Valparaiso in 2011-2012 with Thompson Seedless (Table 1) and Red Globe (Table 2) using standard fungicides and TG. Both trials were conducted in a completely randomized design (CRD) with 5 and 4 treatments respectively and 9 replications per treatment (9 clusters). Two applications at 14 days interval were sprayed with a water volume equivalent to 500L.ha-1. Severity (percentage of rotten berries per cluster) was assessed before harvest. Table 1. Severity (percentage of rotten berries per cluster) and % of Control observed in table grapes cv. Thompson Seedless at harvest. Los Andes, Valparaiso, Chile 2011-2012. Treatments Grey Mould Severity (%) Control (%) 6.9 b 63.1 Pyrimethanil 40% 1.0L.ha 8.8 a 52.9 Pyraclostrobin 25% 750mL.ha-1 1.6 b 91.4 9.2 b 50.8 Timorex Gold 2.0L.ha -1 X -1 Difenoconazole 25% 200mL.ha -1 Untreated Control 18.7 a Means follow by same letter are not different according Tukey (α < 0.05) X Table 2. Severity (percentage of rotten berries per cluster) and % of Control observed in table grapes cv. Red Globe at harvest. Los Andes, Valparaiso, Chile 2013-2014. Treatments Timorex Gold 1.5L.ha -1 Timorex Gold 2.0L.ha -1 POSTER PRESENTATIONS Cyprodinil + Fludioxonil 900g ha -1 Grey Mould Severity (%) Control (%) 0.59 b 70.5 X 0.58 b 71.0 0.34 b 83.0 Untreated Control 2.00 a Means follow by same letter are not different according Fisher (α < 0.05) X 124 7th International Table Grape Symposium Table 3. Incidence (percentage of rotten clusters per plant) and Severity (Percentage of rotten berries per cluster) observed in table grapes cv. Red globe at harvest. Los Andes, Valparaiso, Chile 2013-2014. Treatments Grey Mould Incidence (%) Grey Mould Severity (%) Timorex Gold 1.0L.ha 40.00 ab 2.24 b Timorex Gold 1.5L.ha 13.33 bc 0.13 b Timorex Gold 2.0L.ha 26.67 bc 0.41 b Commercial Standard 0.00 c 0.00 b X -1 -1 -1 Untreated Control 60.00 a Means follow by same letter are not different according Fisher (α < 0.05) 4.85 a X able 4. Severity (percentage of rotten berries per cluster) observed in table grapes cv. Autumn Royal at harvest. Llay-Llay, Valparaiso, Chile 2013-2014. Treatments Sour Rot Severity (%) Grey Mould Severity (%) Timorex Gold 1.5L.ha-1 5.9 bc X 2.1 b -1 Timorex Gold 2.0L.ha 4.2 c 2.4 b -1 Citrus Extract 1.5L.ha 6.9 b 4.2 ab Untreated Control 9.6 a Means follow by same letter are not different according Tukey (α < 0.05) 10.4 a X A third trial performed during 2012-2013 in Requinoa, Rancagua with Crimson Seedless, was conducted in a completely randomized block design (CRBD) with 5 treatments and 4 replications (10 plants per plot with 2 clusters per plant). Seven applications at 7 day intervals with an average spray volume of 800L.ha-1 were sprayed from fruit set up to véraison. Incidence (percentage of rotten clusters per treatment) and severity (percentage of rotten berries per cluster) were evaluated 32 days after harvest and cold storage without using SO2 pads. TDuring 2013-2014 two trials were performed, one in Llay-Llay, Valparaiso, with Autumn Royal and the other in Buin, Santiago with Red Globe. The first trial was conducted in a CRD with 4 treatments and 4 replications (10 plants per plot with 2 clusters per plant). Two applications at 7 days intervals with a water volume of 800L.ha-1 were sprayed on bunches at 18° Brix and 80% of colour on the berries. Before the applications the berries were artificially damaged to ensure the development of the sour rot complex. Severity (percentage of rotten berries per cluster) was evaluated 7 days after the last application (Table 4). The second trial was conducted in a CRBD with 6 treatments and 4 replications (75 cluster per replication). Three consecutive applications at 14 day intervals with a water volume of 1,000L.ha-1 were sprayed from bunch closure to pre-harvest. Incidence (percentage of rotten clusters per treatment) was evaluated at 14 days after last application (Table 5). Table 5. Incidence (percentage of rotten cluster per treatment) and % of Control observed in table grapes cv. Red Globe at harvest. Buin, Santiago, Chile 2013-2014. Treatments Sour Rot Severity (%) Control (%) Timorex Gold 1.0L.ha 12.0 ab 58.6 Timorex Gold 1.5L.ha 11.0 b 62.1 11.0 b 62.1 13.0 ab 55.2 -1 -1 Timorex Gold 2.0L.ha -1 Bacillus subtillis 6.0L.ha -1 X X Untreated Control 29.0 a Means follow by same letter are not different according Fisher (α < 0.05) In Peru two experimental trials were performed during 2013 with Red Globe, located in Villacuri, Ica using a complete randomized block design (CRBD) with 2 applications at 7 days interval from full colour berries and preharvest. There were 5 treatments and 4 replications using a spray volume of 600L.ha-1. Disease severity (percentage of rotten berries per cluster was assessed before application and 7 and 14 days after last application (Table 6). 125 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 6. Severity (Percentage of rotten berries per cluster) observed in table grapes cv. Red Globe at harvest. Villacuri, Ica Peru 2013. Treatments Timorex Gold 1.2L.ha -1 Timorex Gold 1.5L.ha-1 Sour Rot Severity (%) Grey Mould Severity (%) 2.50 b 1.19 b X X 1.50 bc 0.28 c Timorex Gold 1.75L.ha 0.50 cd 0.26 c Timorex Gold 2.0L.ha 0.00 d 0.38 c -1 -1 Untreated Control 31.25 a Means follow by same letter are not different according Duncan (α < 0.05) 3.60 a X Discussion and Significance of the Study Spraying TG at 1.5 and 2.0L.ha-1 as a preventative treatment effectively controlled grey mould, had curative effect on the sour rot complex and suppressed the development of existing lesions and formation of colonies of various fungi complexes. TG at 2.0L.ha-1 also reduced sporulation of the fungal complex in infected tissue. TG as a natural bio-fungicide does not harm beneficial insects and bees, has no residue limitations (is exempt of MRLs) and may complement biological and synthetic fungicides used in table grape production. It shows promise as an attractive tool for use in anti-resistance programs. POSTER PRESENTATIONS 126 7th International Table Grape Symposium ID 3 Agronomic and qualitative performances of some table grape Dalmasso crosses (Vitis vinifera L.) grown in Piedmont (NW of Italy) Antonio Carlomagno, Alessandra Ferrandino, Olga Kedrina and Vittorino Novello* Dipartimento di Scienze Agrarie, Forestali ed Alimentari, Università di Torino, Largo P. Braccini 2, I-10095 Grugliasco (TO), Italy * Corresponding author: Tel: +39011 670 8758, Email: [email protected] Background and Aims Table grape cultivation in Italy covers an area of 37,305 hectares (Istat, 2010) with an average farm size of 2ha. Global production of table grapes is over 20.7 million tons (OIV, 2008). Asian countries are the major producers and China is the world leader with 4.6 million tons. Italy produces 1.3 million tons of which 0.8 million tons is for internal consumption. In Europe, Italy is the main producer and exporter of table grapes (Lamacchia, 2013). Production is concentrated in Southern Italy, mainly in the Apulia and Sicily regions, where the climate conditions are most favourable. The varieties most widely grown and consumed are Victoria (white) and Black Magic in the early part of the season and Italia (white) and Red Globe in the later part of the season. In Italy, seeded varieties are more widespread than seedless varieties as the commercially available seedless varieties (e.g. Sugraone and Crimson Seedless) require different approaches to in agronomic management. Specific management practices required for seedless varieties include long pruning systems (6-7 canes with at least 30 buds per vine), high planting distances, polyethylene film covering, fertigation and the use of growth regulators to produce a satisfactory product. In Italy the consumers prefer the traditional and local varieties with seeds, whereas the foreign consumers prefer to eat seedless varieties, especially in Northern Europe. To satisfy these markets, several new seedless varieties have been introduced by Italian growers (such as Apulia, Summer Royal, Midnight Beauty, Sophia Seedless, etc.). The Piedmont region, located in Northwest Italy, is famous for the production of several premium wines and wine viticulture is widespread, especially in the hilly areas. However, in these areas, there is only minimal production of table grapes which are used for family consumption and grown in association with other tree fruits rather than in specialised vineyards. Usually, local consumers buy table grapes imported from Southern Italy or other countries (e.g. Chile, Argentina, South Africa, etc.) at the fruit and vegetable markets. Apples, pears, peaches, plums and kiwifruit are widely cultivated in the plains at the foot of the Alps. However in recent years, growers have been forced to eradicate their kiwifruit orchards because of a major outbreak of the pathogen, Actinidia bacteriosis (Pseudomonas syringae pv. actinidiae). Table grape growing may provide an alternative crop for these growers and also reuse the kiwifruit orchard trellis structure. In order to promote the development of the local table grape market, diversify the growers’ source of income and offer an alternative to the production of kiwifruit, a recovery and enhancement program of some table grape Dalmasso crosses produced by Prof. Dalmasso has begun. He commenced a program of crossbreeding in 1950 with the aim to select table genotypes suited to cultivation in North Italy which were improvements on some existing table grape varieties, such as Bicane which is a female variety and Muscat Hamburg which has irregular ripening of berries inside the same bunch. Moreover, these crosses represent a reservoir of biodiversity which has not been fully characterised. In this paper, we discuss agronomic and qualitative performances of some table grape Dalmasso crosses (ID) of potential interest for the cultivation in Piedmont region. Experimental Procedure and Results 7th International Table Grape Symposium 127 POSTER PRESENTATIONS The data collection was carried out in a vineyard located at Chieri (Turin Province, 45°1‘0“N 7°49‘0“E, 350m a.s.l.). The vines, grafted onto Kober 5BB, were planted in 1975 (NW-SE row orientation with NE exposure) in a clay soil at a spacing of 2.0 × 1.0m and trained to the vertical shoot positioned system with arched cane pruning. Each variety or selection was planted in two plots with two plants in each plot. In 2013 agronomic features and qualitative parameters of grapes were evaluated. The different harvest period for each cross was identified according to the Pulliat’s rank (I period: contemporary ripening with ‘Chasselas dorée’; II p.: 15 days after I period; III p.: 15 days after II p.; IV p.: 15 days after III p.). The following genotypes have been evaluated: Teresita B. (Moscato d’Amburgo N.× [Bicane B. × (Regina B. × Terra Promessa B.)]), ID IV/60 N.(under parental SSR investigation), VI/6 B.(Bicane B. × Regina B.) and XI/20 N.(Moscato d’Amburgo N. × Regina B.). The genotypes have been evaluated in terms of fruit characteristics and agronomic performance. Furthermore, we have evaluated the production quality through the assessment of technological maturity (total soluble solids, titratable acidity, pH), total anthocyanins and flavonoids (Di Stefano and Cravero, 1991), antioxidant activity (Re et al., 1999) and varietal volatile compounds (Ferrandino et al., 2012). Statistical analysis was carried out by the SPSS Statistics software (IBM). Teresita (II/III period of harvest), is a white variety with medium vigour, low fertility in basal buds and a production of 8.75t/ha. In unfavourable years it has problems with low fruit-set. The berry is globose with medium skin firmness and muscat-like flavour with a predominance of linalool and geraniol (Figure1). During 2013 season, black ID IV/60 showed abundant production (47.50t.ha-1), high Ravaz index (i.e. the yield to pruning weight ratio of 11.44) and high titratable acidity (9.34g.L-1 tartaric acid). It has big and attractive cluster with intense blue-violet globose berries (6.13g), with an amount of total skin anthocyanins of 479.40mg.kg-1 of berries. Furthermore, it showed a good resistance against downy mildew and grey mould. White ID VI/6 (II period) has good productivity (22.50t.ha-1) with big, compact and attractive clusters (538.50g) and large globose or deformed berries (9.40g). Both its very high vigour with a low Ravaz index (2.20) and low basal bud fertility suggest that the adoption of expanse training system (e.g. pergola) with long pruning system is required. ID XI/20 was characterized by high yield (37.50t.ha-1), big bunch (468.75g) and globose berries (6.84g) with low total skin anthocyanins content (152.76mg.kg-1 of berries). In the 2013 season, all table grape genotypes produced good compositional characteristics, in particular their total soluble solids (TSS) were greater than the reference minimum value for table grapes (12° Brix, OIV 2010). Teresita reached the highest TSS content (21.20° Brix). ID IV/60 showed quite high levels of titratable acidity, an indication that growers should pay particular attention to canopy management with this selection. It also produced compact clusters requiring fruitlet removal after fruit-set to minimize problems in wet seasons. IV/60, VI/6 and XI/20 genotypes showed good resistance against Plasmopora viticola and Botrytis cinerea, suggesting a good adaptability in cool climate growing conditions like the Piedmont’ areas. The highest antioxidant activity was found in the seeds (Table 1). This feature is very important, because it suggests that the seeds could be used in non-food industries, such as in cosmetics. The study of skin and pulp antioxidant activity is important for their human health implications. The results of antioxidant activity for these genotypes highlight the importance of all phenolic classes, not just colour in determining this activity (Table 1). In this regard, C6 compounds (especially hexanal, (Z)-3-hexenal, (E)-2-hexenal and hexanol) and Sesquiterpenes are very important in non-aromatic genotypes. Teresita, produced an interesting muscat-like flavour, related to the predominance of monoterpenes (Figure 1b). The monoterpene profiles indicate that ID VI/6 had a molecule belonging to the menthol-family (29%). ID IV/60 had detectable levels of (E)-geranylacetone as monoterpenes whereas (E)-geranylacetone dominated the XI/20 genotype. Discussion and Significance of the Study In Italy the main table regions are in the South, for climatic reasons. However, the results obtained in this study indicate strong potential to spread the growing of table grapes into North Italy, including the Piedmont’ area. Furthermore, some Dalmasso crosses show significant improvement over their corresponding parents, e.g. VI/6 compared to Bicane does not show flower abnormality. Moreover, although the consumers (especially in Northern Europe) prefer seedless varieties, the Dalmasso crosses offer potential for Northern Italian regions because of their adaptability to cool climate growing conditions, ability to meet satisfactory quality standards, the interesting nutraceutical characteristics of berries and the bond between growing area and origins of the genotypes. POSTER PRESENTATIONS 128 7th International Table Grape Symposium Figure 1. Free varietal volatiles profile (a) and monoterpenes profile (b) of table grape Dalmasso crosses (Stir Bar Sorptive Extraction technique). Table1. Evaluation of antioxidant activity of skin, pulp and seeds of table grape Dalmasso crosses (ABTS radical cation decolourisation assay). Antioxidant activity (µmol Trolox g-1 fresh weight) skin pulp seeds average ± st err average ± st err average ± st err Teresita B 235.38ab 4.51 0.46c 0.05 863.43b 45.26 ID IV/60 n 266.71a 49.63 2.20b 0.43 1088.23ab 121.61 ID VI/6b 143.55b 10.12 1.23c 0.22 1385.89a 104.06 ID XI/20 n 180.72ab 14.13 3.45a 0.11 1062.35ab 88.47 Test Tukey-b a=0.05 a=0.05 a=0.05 Acknowledgements AGER Italian Vitis Database project for financial support, and technical staff of experimental farm ‘Tetti Grondana’, Chieri (Turin Province). References Di Stefano R and Cravero MC. 1991. Metodi per lo studio dei polifenoli dell’uva. Rivista di Viticoltura e di Enologia 2: 37-45. Ferrandino A, Carlomagno A, Baldassarre S, Schubert A. 2012. Varietal and pre-fermentative volatiles during ripening of Vitis vinifera cv Nebbiolo berries from three growing areas. Food Chemistry 135: 2340-2349. Lamacchia G. 2013. Uva da tavola tra crisi economica ed andamento climatico negativo. L’Informatore Agrario 47: VI-IX. Re R, Pellegrini N, Proteggente A, Pannala A, Yang M, Rice-Evans C. 1999. Antioxidant activity applying an improved ABTS radical cation decolourization assay. Free Radical Biology and Medicine 26: 1231–1237. 129 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 4 Inconsistent yielding between years is a threat to the sub-tropical table grape industry in Queensland Kishor C Dahal1,*, SP Bhattarai1, KB Walsh1, DJ Midmore1 and DR Oag2 School of Medical and Applied Sciences, CQ University, Bld 361, Rockhampton Queensland 4702 Applethorpe Research Station, DAFF. PO Box 501, Stanthorpe Queensland 4380 * Corresponding author: Tel: +61 7 4930 9419, Email: [email protected] 1 2 Background and Aims The sub-tropical table grape industry in Australia is of high economic importance as the seasonally early harvest time coincides with a favourable market price. However, the average yield of grapes grown in sub-tropical areas is low compared to the average in Australia (3.94 vs. 11.2t ha-1, 2011/12 data, ABS, 2013). The poor yield in sub-tropical table grape varieties is further compounded by a high level of inconsistency of yield across years. Experimental Procedure and Results The analysis of the long-term yield of three popular table grape varieties (Menindee Seedless, Flame Seedless and Red Globe) presented in Figure 1 shows that yields for one property using standard production practices in the subtropics of Queensland fluctuated wildly between years. Furthermore, not all varieties show the same direction of yield fluctuation (increase or decrease) in the same year. 18 18 Menindee S eedles s (12932) F lame S eedles s (4347) R ed G lobe (2511) 16 4 4 2 2 0 0 20 20 20 20 20 20 20 20 20 20 20 13 6 12 6 11 8 10 8 09 10 08 10 07 12 06 12 05 14 04 14 03 Marketable yield (t/ha) 16 S uc c es s ive year Figure 1. Variation in Yield of Table Grapes Varieties in Sub-tropical Climate of Australia. [Note: Value in parenthesis represent the total number of vines counted in each year to calculate average marketable yield] The extent of variation in yield of Menindee Seedless over an 11 year period (2003-2013) varied almost 7 fold (from the lowest in 2011 to highest in 2005), with a year on year yield fluctuation of >30% in 6 out of 10 years. Annual variation in yield of 30% has been reported for vines in a temperate environment (Boss et al., 2003) while inconsistent yield patterns of up to 75-80% have been reported for table grape vines in a subtropical environment (Considine, 2010; Gordon, 2012). POSTER PRESENTATIONS Amongst the three varieties, Flame Seedless shows less variation, but had the lowest overall yield. A fourth variety grown at the same site, Muscat Hamburg, had much less between-year yield variation and had greater fruitfulness, than the other three varieties. However, it is a seeded variety and not produced in commercial quantities by the grower because of lower consumer demand. 130 7th International Table Grape Symposium Discussion and Significance of the Study Due to the extreme irregularity in yield between seasons, the sub-tropical table grape industry faces annual marketing uncertainty in addition to low yields in some years. Our research aims to overcome some of these limitations to the industry. It is known the level of vine carbohydrate reserves (starch and sugar) in the grape vine is abruptly depleted within a short period of time from bud-burst to flowering and reaches its lowest level during flowering (Holzapfel et al., 2009). Over one half of the reserves are stored in the roots (Holzapfel et al., 2009). The stored carbohydrates in this short period are mobilised to different sinks particularly to support root growth, bud burst, shoot growth, flowering and next season bud differentiation immediately after the winter season. Past research in temperate climates has indicated an association between carbohydrate level during the period from bud burst to flowering on bud fruitfulness in the next season, bud necrosis, current season yields and vegetative growth of the vine (Rawnsley and Collins 2005; Holzapfel, 2009; Vasudevan et al., 1998). Sub-tropical areas are typically characterised by a short, mild winter and a short growing season from budburst to harvest (Oag, 1999). This short growth period may influence carbohydrate synthesis, storage and mobilization, which in turn may impact on bud fruitfulness and fruit set (determinants of yield). Gibberellins are also believed to trigger current season fruit set and next season bud-fruitfulness (Hashim, 2010). We propose to investigate carbohydrate reserve levels, rootstock contributions, and timing of gibberellin applications and their possible linkages with bud-fruitfulness and inconsistent yield patterns. The goal is to improve management of vine fruitfulness to achieve consistent and predictable yields across years. Acknowledgements Kishor Dahal is supported by an Australia Award (Department of Foreign Affairs and Trade) scholarship under a CQUni PhD program. References Australian Bureau of Statistics. (2013). Agricultural commodities, Australia, 2011-2012 (Cat. No. 71210). Canberra, Australia: ABS. Retrieved from http://www.abs.gov.au/AUSSTATS/[email protected]/DetailsPage/7121.0201112?OpenDocument Boss PK, Buckeridge EJ, Poole A, Thomas MR. 2003. New insights into grapevine flowering. Functional Plant Biology 30: 593-606. Considine M. 2010. New project to target environmental triggers in the tropics. The Vine 6(5): 8-9. Gordon, C. 2012. High prices for early season Western Australia table grapes. The Vine (8)1: 18. Hashim JM. 2010. Influence of gibberellic acid applied at bloom and berry set on fruit quality of ‘Scarlet Royal’ and ‘Sweet Scarlet’ table grapes. Table grape plant growth regulator workshop, Visalia convention center, June 29, 2010, University of California Cooperative Extension. 1-4 pp. Holzapfel B, Smith J, Rogiers S, Quirk L. 2009. Management of carbohydrate reserve accumulation as a tool for regulating vine productivity and fruit quality. Grape and Wine Research and Development Corporation, final report, project number: CSU 05/01. National Wine and Grape Industry Centre (NWGIC). 83p. Oag DR. 1999. Overview of the Queensland table grape industry: 1999. In: ‘5th Australian Table Gape Technical Conference’, 6th and 7th October 1999, Murray Valley Table Grape Growers Council, Mildura. Rawnsley B and Collins C. 2005. Improving vineyard productivity through assessment of bud fruitfulness and bud necrosis. Grape and wine research and development corporation, final report, project number: SRI 02/05. South Australian Research and Development Institute (SARDI). 100 p. Vasudevan L, Wolf TK, Welbaumand GG and Wisniewski ME. 1998. Reductions in bud carbohydrates are associated with grapevine bud necrosis. Vitis 37(4): 189-190. 131 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 5 Performance of table grape JD 874 grafted onto different rootstocks in two regions of São state, Brazil Mara Fernandes Moura*1, Marco Antonio Tecchio2, Erivaldo José Scaloppi Júnior3, Maurilo Monteiro Terra1 and Erasmo José Paioli Pires1 Centro APTA de Frutas. Instituto Agronômico - IAC. Av. Luiz Pereira dos Santos. 1500. Zip Code 13214-820. Jundiaí. SP. Brasil 2 Departamento de Horticultura. Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Rua José Barbosa de Barros. n. 1780. Zip Code 18610-307. Botucatu. SP. Brasil 3 Pólo Regional do Noroeste Paulista, Agência Paulista de Tecnologia dos Agronegócios - APTA. Rodovia Péricles Belini, km 121. Caixa Postal 61. Zip Code 15500-970. Votuporanga/SP. Brazil * Corresponding author: Tel: + 55 11- 4582 7284, Email: [email protected] 1 Background and Aims The Instituto Agronômico (IAC) has been doing work with different cultivars of table grapes, aiming to provide alternatives for diversification in grape production. Among the cultivars that have potential, there is the ‘JD 874’. The hybrid ‘JD 874’, was developed by the researcher Júlio Inglez Seabra de Sousa in Jundiaí, São Paulo from a cross between ‘Seyve Villard 5276’ and ‘Muscat Hamburg’. The variety is a red seeded grape, with medium size, semi-crunchy, slightly muscatel flavoured berries with a medium length growth cycle (Sousa and Martins, 2002). Evaluation work of this variety JD 874 is being conducted in order to verify the affinity when grafted onto different rootstocks and their performance in two regions of the State of São Paulo. Experimental Procedure and Results We evaluated the productivity and physic-chemical characteristics of clusters, berries and stems of the variety grafted onto different rootstocks at Jundiaí and Votuporanga, State of São Paulo. The experiments were conducted in the experimental area of Centro APTA de Frutas, located in Jundiaí, and in the Pólo Regional do Noroeste Paulista, located in Votuporanga, SP. In both study areas, the treatments were a combination of the variety grafted onto rootstocks IAC 313 ‘Tropical’, IAC 766 ‘Campinas’, IAC 572’ Jales and IAC 571-6 ‘Jundiaí’. In the experiment conducted in Jundiaí, the rootstock ‘Golia’ was also used. The experimental design was a randomized block with four replications in Jundiaí and six replicates in Votuporanga. The training system was a cordon with three catch wires. The plants were spaced at 2.0 x 1.0m in Jundiaí and 2.0 x 1.5m in the Votuporanga region. Evaluations in each experimental area in a production cycle included the following variables: average number of clusters per plant; yield in kg plant-1; weight, length and width of the clusters, rachis, berries and stems; total soluble solids; pH and titratable acidity. The data from in each region were was analysis using ANOVA. Significant differences between treatment means were verified by Tukey test at 5% probability. In Jundiaí, rootstocks influenced fresh mass of clusters, berries, berry length, fresh weight of rachis, rachis width and average yield per plant. The JD 874 variety grafted onto rootstock IAC 571-6 showed highest mean for average yield per plant although the width and fresh weight of berry stems did not differ statistically from the rootstock IAC 572. The hybrid grafted onto rootstock IAC 572 had the highest mean fresh weight of cluster, fresh berry and berry length. Thus, the rootstock IAC 572 and IAC 571-6 positively influenced the production and physical characteristics of the fruits in the eastern region of São Paulo State. For the chemical characteristics of the juice there was no difference between the rootstocks. In Votuporanga, rootstocks influenced the average number of clusters per plant, the average yield per plant, fresh weight of the clusters, fresh weight of berries, berry length, width of berries, fresh weight of stems, length of rachis and rachis width. For the mass of the cluster, the highest average was obtained by hybrid grafted onto the rootstock IAC 572, but there was not a statistical difference from the rootstock IAC 766. For production traits best results were obtained using the rootstock IAC 766, which provided the highest average for number of clusters per plant and yield per plant. Similar results were found by SATO et al., (2009) who found higher productivity of Isabel variety grafted onto rootstock IAC 766. The rootstock IAC 572 had the highest average for fresh weight, length and width of cluster and rachis. There was no influence of rootstock on the chemical characteristics of the variety in Votuporanga. POSTER PRESENTATIONS 132 7th International Table Grape Symposium Discussion and Significance of the Study We conclude that for Jundiaí, best productive performance was obtained with the rootstock IAC 571-6. In Votuporanga was the rootstock IAC 766 which provided greater productivity for the variety, but did not differ from the rootstock IAC 572 which provided better physical characteristics of clusters, berries and stems. References Sato AJ; Silva BJ Da; Bertolucci R; Carielo M; Guiraud MC; Fonseca ICB; Roberto SR. 2009. Evolução da maturação e características fisico-químicas de uvas da cultivar Isabel sobre diferentes porta-enxertos na Região Norte do Paraná. Ciências Agrárias, Londrina. 30(1):11-20. Souza, JSI de and Martins FP. 2002.Viticultura brasileira: principais variedades e suas características. Piracicaba: FEALQ, 368p. 133 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 6 Ethephon and abscisic acid for improving colour of ‘Crimson Seedless’ table grape in the Vale do São Francisco, Northeastern of Brazil in 2012 growing season PC de S Leão*, MAC Lima, JP Dias and DC. da Trindade Embrapa Semiárido, BR 428, Km 152, PO Box 23, Zip Code: 56302-970,Petrolina, PE, Brazil Corresponding author: Tel: 055873866-3668. Email: [email protected] 1 * Background and Aims The Vale do São Francisco, in the Northeast region of Brazil, is one of the most important tropical grape growing regions in the world. In this region there are 11,000ha of cultivated table grapes. This region is also responsible for 99% of Brazilian exports of table grapes. ‘Crimson Seedless’ grapes growing in these tropical conditions generally exhibit clusters with a poor and uneven red colouring, especially when they are harvested in October, in the hottest period of the year. Crop practices, such as thinning, leaf removal, topping and tying are undertaken by growers to minimise shading but is insufficient to solve the problem of poor colour development. For that reason, some plant growth regulators (PGRs) have been adopted. The aim of this study was to assess the effect of different concentrations and time periods of application of ABA and ethephon, on the properties of colour and quality of ‘Crimson Seedless’ grapes produced in the Vale do São Francisco. This study, undertaken in the 2012 season, aimed to improve the colour of grape cv. Crimson Seedless through the application of plant growth regulators. Experimental Procedure and Results The study was conducted over a single season in 2012 in Petrolina, PE (9° 23’S, 40° 39’ W, 394m Alt.). Eight-year-old commercial Vitis vinifera L. cv. ‘Crimson Seedless’ vineyard grafted on IAC 313 rootstock were trained to bilateral cordons, supported by an overhead trellis system, and cane (10-12 buds) pruned. The vines were spaced 4.0m within rows and 5.0m between rows. The vineyard was drip irrigated and vineyard management and fertilisation was similar to the practices recommended in that region. A randomised complete-block design was used with a single vine per treatment replicate with two adjacent vines in-row, between replicates, used as buffer vines. There were ten treatments and four replications. Treatments consisted of Ethephon and Abscisic Acid (ABA) or the combination of both PGRs, applied at two phenological phases: first one in berry softening or véraison and second one was carried out about 15 before harvest. The treatments were as follows: • • • • • • • • • • (T1) control (no treatment) (T2) Ethephon (T3) ABA, 400mg.L-1 at 117 days after pruning (DAP) (T4) ABA, 200 + 200mg.L-1 at 97 and 117 DAP (T5) ABA, 400mg.L-1 at 97 DAP (T6) ABA, 600mg.L-1 at 117 DAP (T7) ABA, 300 + 300mg.L-1 at 97 and 117 DAP (T8) ABA, 600mg.L-1 at 97 DAP (T9) Ethephon + ABA, 200mg.L-1 both of them applied at 97 DAP (T10) Ethephon + ABA , 300mg.L-1 at 97 DAP Pruning was held on 13/07/2012, the first application of ethephon and ABA on 18/10/2012, the 2nd application on 07/11/2012 with harvest on 21/11/2012. The Commercial products were Ethrel® 720 (1mL.L-1), and VBC 30101 (ProTone®) provided by ValentBiosciences®, USA, containing 100g of abscisic acid (S-ABA) per litre, the latter still not registered in Brazil. A non-ionic wetter/spreader surfactant (0.5mL.L-1) was added to the solution for all treatments. The PGRs were applied directly to the clusters with a handheld sprayer until runoff, the total volume of solution used was 1.0L per plant or 500L.ha-1. POSTER PRESENTATIONS 134 7th International Table Grape Symposium Clusters from each vine were harvested after most of the fruits were considered to have exceeded the minimum market requirements of 16.5% total soluble solids (TSS), and 20:1 total soluble solids:titratable acidity ratio. Only commercially acceptable clusters were harvested. The grape yield components and physicochemical characteristics of all treatments were assessed by determining the yield (kg) and number of clusters in classes of colour (Class 1: 0 - 25% of uniform red colour of berries; Class 2: 26 - 60%; Class 3 : 61- 90% and class 4: 91 - 100% of red berries and uniform colour); mass of cluster (g); length and diameter of berry (mm); firmness and elasticity of berry; soluble solids; titratable acidity; anthocyanins content. The surface colour of berries in each sample were measured with a reflectance colourimeter to obtain the colour index of red grapes (CIRG) calculated as CIRG = (180− h°)/(C*+L*), where L* is the lightness and corresponds to a black-white scale (0, black; 100, white), h° is the hue angle on the colour wheel, and C* is the chroma, a measure of the intensity of colour, which begins at zero (achromatic) and increases in intensity. Data were subjected to analysis of variance and the means were compared by Tukey test ( P < 0.05 ). The results showed that there was an increase of 39% in yield when ethephon + ABA 300mg.L-1 were applied compared to the treatment ABA 400mg.L-1 at 97 DAP. Those effects were observed as a consequence of an increasing in mass of clusters. On the other hand, the other treatments were not significantly different from each other, which do not allow associating those effects in increasing the mass of cluster and the yield per plant with use of PGRs. In regard to the colour coverage and colour intensity of ‘Crimson Seedless’ berries, significant differences were observed only in the number of clusters in classes 1 and 4. A larger number of clusters in class 1 were observed in control, but did not differ from treatments with ABA, independent of the dose, number and timing of application. On the other hand, the fewer clusters in class 1 were observed in the following treatments: ethephon + ABA 300mg.L-1, ethephon + ABA 200mg.L-1 and ethephon alone, respectively with 9 (8.9%), 14 (13%) and 17 (16 %) of clusters per plant. The best responses to improve colour of ‘ Crimson Seedless’ berries was shown in class 4, where larger number of clusters were obtained in the treatments combining ethephon and ABA (200 or 300mg.L-1) These treatments differed significantly from all the other treatments. All components of the colour were affected by treatments, the lightness of surface of berries increased in control, ethephon, ABA 400 mg.L-1 applied at 117 DAP or 97 DAP and ABA in two applications of 200mg.L-1 at 97 and 117 DAP. The higher colour intensity (chroma) was observed in berries treated with ABA 600mg.L-1 at 97 DAP. However, treatments combining ethephon and ABA at 200mg.L-1 and ABA 600mg.L-1 at 117 DAP showed similar responses. The values of hue angle (h°), indicated closest tones of red (low values of h°) were observed in the berries that received ethephon alone or combined with ABA. As a consequence of the integration of the values of attributes mentioned in particular the direct relationship with h°, the highest values of CIRG were observed in berries treated with ethephon alone, ethephon combined with ABA (200 or 300mg.L-1), ABA applied twice (200 or 300mg.L-1) and ABA 400mg.L-1 at 97 DAP. The anthocyanin contents were higher in the surface of grapes treated with ethephon + ABA 200mg.L-1 but that effect did not differ from the ethephon + ABA 300mg.L-1 and ABA 300mg.L-1 applied twice at 97 and 117 DAP. The berry size, total soluble solids and titratable acidity were not affected by PGR treatments. Other studies have also showed similar results indicating that ABA increases the synthesis of anthocyanins without changing the size of clusters, size of berries and flavour. Discussion and Significance of the Study The results obtained under tropical conditions of Vale do São Francisco showed that combination of growth regulators ethephon and ABA (200 or 300mg.L-1) and ABA applied twice at 300mg.L-1 improve the level of anthocyanins and colour of berries in ‘Crimson Seedless’ grapes. However there was no treatment effect on soluble solids, titratable acidity, size of berry and yield. The decision to adopt ABA and/or ethephon can be guided by the costs involved in the application, presence of residues in fruit and acceptance of products by certification systems for safe and sustainable production. 135 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 7 Moving in on mealybugs in Western Australian table grape vineyards Stewart Learmonth* and Helen Collie Department of Agriculture and Food Western Australia, Manjimup, Western Australia, 6258 * Corresponding Author: Tel: +61 8 9777 0167, Email: [email protected] Background and Aims Table grapes are a high value fresh fruit horticultural crop grown in coastal regions of Western Australia, from Carnarvon in the sub tropics to Busselton in the temperate south west. Mealybugs are present in all areas of production and represent a threat to the marketability of produce. The presence of live mealybugs in bunches results in rejection of fruit at harvest. Figure 1. Obscure mealybug (left) and longtailed mealybug adults differ where the spines on the end of the body are shorter than the body and much longer, respectively. Two species of mealybugs are present in WA table grape vineyards – longtailed mealybug, Pseudococcus longispinus and obscure mealybug, P. viburni (Figure 1). Longtailed mealybug is more prevalent, especially in vineyards in the Swan Valley. Obscure mealybug occurs in greater numbers in lower south west vineyards. Longtailed mealybug has been recorded in WA since the late 1800’s, while obscure mealybug has been recorded only for about the past 40 years. With the suite of insect pests that occur in WA table grape vineyards and the low tolerance level for insect presence by the market, growers rely on insecticide use to attempt to provide insect pest free produce. The reliance on insecticides is further necessitated by the relative paucity of natural enemies of mealybugs. This is evident after harvest in situations where mealybug numbers are sometimes very high and few natural control agents are observed. Experimental Procedures and Results Research, commencing in 2012 to improve reliability of control of mealybugs in WA table grapes involved: POSTER PRESENTATIONS 136 • Getting baseline data on the abundance, seasonality and species of mealybugs in WA table grape vineyards. For this, leaves and mature bunches were monitored from spring to senescence and dormant vines in selected blocks in ten commercial table grape vineyards in the southern growing regions of WA. Sticky traps using synthetic pheromone lures for each of the mealybug species were placed at three of these vineyards during each season. • Comparing the effectiveness of the main currently registered insecticides for mealybug control during the 2013/14 growing season. • Examining the effectiveness of post-harvest applications of the same insecticides plus two other products applied during dormancy on mealybug abundance the following season. 7th International Table Grape Symposium Baseline data Monitoring for mealybug in Western Australian table grape vineyards from the Swan Valley to Busselton showed that for both seasons there was a wide range in abundance levels. The abundance of mealybug varied from virtually absent to high levels with consequent levels of threat to producing quality table grapes free of live mealybugs. This indicates that improvements in management practices can be made. In those vineyards where the pest is either present at low levels or virtually absent, leaf monitoring in spring would be beneficial in terms of treating for the pest only if it became sufficiently abundant to warrant insecticide application. In vineyards heavily infested with mealybug, early action such as use of the soil applied systemic insecticide could be considered in addition to monitoring during the growing season. However the range in abundance of mealybug across WA’s table grape growing regions in the south-west also reflects a lack of understanding of factors that drive their populations. This may include the possibility that insecticide use may be removing natural control agents or subtle vineyard management practices may make some vineyards less suitable as breeding sites for mealybug populations. Because the mealybug infestation level on leaves near the end of the growing season was reflective of the level of infestation on whole vines, leaf sampling at this time would appear to be sufficient to define the risk of damaging mealybug populations for the following season and so avoid the more time consuming monitoring of dormant vines. This information would help in deciding the appropriate management strategy for the following season. Sticky traps using synthetic pheromone lures Results of the pheromone trapping, observations within vineyards and examining microscope slides of field collected adult mealybugs confirmed the presence of tuber mealybug in at least three table grape vineyards in the lower south west of WA. Whether this has implications in relation to mealybug pest management needs to be taken into account. Also, the pheromone traps showed adult males were least abundant during the main part of the growing season and most abundant during late summer to autumn. Effectiveness of the main currently registered insecticides The insecticide trial that compared a range of treatments on controlling mealybug during the season showed that the most effective treatment was the older organophosphate chemical Tokuthion®. Given the duration of use of this insecticide in the Swan Valley, it indicates that longtailed mealybug, the dominant species in the Swan Valley, has not developed insecticide resistance to this product. With the exception of the clothianidin (Samurai®) drench treatment, all other insecticide treatments demonstrated activity against the mealybug. Even though there was no untreated treatment in this trial, the higher occurrence of mealybug in the Samurai® drench treatment showed that insecticide activity occurred for the other treatments. The lack of efficacy of the Samurai® drench treatment indicates that there may be some limitations in the way this insecticide was applied in this trial. Although irrigation was used at the time of application, rainfall was very low either side of the time of application which may have resulted in poor movement of the insecticide into the root zone to allow uptake. The reasonably consistent presence of mealybugs over the trial period and beyond up to harvest suggests survival of mealybugs on the cordon, crowns and trunks of vines. This is supported to some extent by the lack of significant difference in mealybug numbers on the wood across the treatments despite differences in earlier leaf infestation levels. This fact highlights a lack of knowledge on the biology of the mealybug in table grapes. A better understanding of the timing of occurrence of mealybugs and their location on vines during the season would assist in designing effective management strategies to better control the insect. Effectiveness of postharvest applications 7th International Table Grape Symposium 137 POSTER PRESENTATIONS While the trial that involves insecticide applications post-harvest and during vine dormancy has yet to be completed, early results show good levels of control of post-harvest leaf feeding populations of mealybugs and is reflected in counts both on leaves and later on vine wood. Assessments of mealybug on foliage in spring will confirm whether these treatments are beneficial compared with control only during the growing season. Discussion and Significance of the Study Two species of mealybugs are known to occur in Western Australian table grape vineyards. The more common is longtailed mealybug and at much lower prevalence is obscure mealybug. These insects are a problem even at low density as cosmetic pests in harvested grapes. Although mealybugs are vectors of viruses that affect vine health in Western Australia, this aspect of the pest status of mealybugs is less important. The low pest density threshhold for mealybugs and paucity of natural enemies leads to the reliance on insecticides for the management of this pest in table grape vineyards. Research has been conducted on the biology of the pest in relation to the use of registered insecticides seeking to maximise their efficiency. Key aspects to mealybug control are well timed insecticide applications during infestation of the canopy soon after budburst in spring. Control during the season is confounded by the presence of a proportion of the population under the bark of vines. Also, monitoring mealybug populations after harvest shows that breeding activity continues through to senescence. The value of postharvest control of mealybugs to protect the next crop of table grapes is a major aim of current research. Another aspect of the research is the use of pheromone traps to help understand the role of male mealybugs in seasonal population dynamics. Further studies are recommended to: • Build confidence in monitoring systems to base decisions on the need for and timing and type of insecticide applications to control mealybugs. • Develop appropriate insecticide use strategies to protect tablegrape vineyards for the entire season; • Clarify the proportion of mealybugs that belong to either species • Improve our understanding of the role of adult males in the seasonal cycle of mealybugs and from this, investigate whether pheromone traps can assist in monitoring and in the future to consider whether mating disruption could be implemented. • Clarify the abundance and identity of natural enemies with an emphasis on the wasp parasitoids with a view to the possibility of making introductions to WA. References Daane KM., Almeida RPP, Bell VA, Walker JTS, Botton M, Fallahzadeh M, Mani M, Miano JL, Sforza R, Walton VM, Zaviezo T. 2012. Chapter 12 Biology and Management of Mealybugs, pp 271-307. In N.J. Bostanian et al., (eds.), Arthropod Management in Vineyards: Pests, Approaches, and Future Directions, DOI 10.1007/978-94-007-4032-7_12, Springer Science+Business Media B.V. Learmonth, SE and Collie HM. 2014. Insecticide management of mealybugs in WA table grapes 2013/14. Department of Agriculture and Food Western Australia. Trial Report. Walton VM, Dalton DT, Daane KM, Kaiser C, Hilton RJ. 2013. Seasonal Phenology of Pseudococcus maritimus (Hemiptera: Pseudococcidae) and Pheromone-Baited Trap Survey of Four Important Mealybug Species in Three Wine Grape Growing Regions of Oregon. Annals of the Entomological Society of America 106(4): 471-478. POSTER PRESENTATIONS 138 7th International Table Grape Symposium ID 8 Effects of box liner perforation area on methyl bromide diffusion into table grape packages during fumigation JG Leesch1, JL Smilanick1,*, JS Muhareb2, JS Tebbets3, JM Hurley2 and TM Jones2 Retired, USDA-ARS San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648 USA 2 DFA of California, 1855 South Van Ness Avenue, Fresno, CA 93721 USA 3 USDA-ARS San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648 USA * Corresponding author: Tel: 559 859 3547, Email: [email protected] 1 Background and Aims Plastic liners are used inside boxes of table grapes to retard moisture loss from the grapes and to contain sulfur dioxide gas released inside the packages to control postharvest decay. However, to control organisms of quarantine concern, regulators specify exported packages must be fumigated with methyl bromide (MB), and to enable adequate diffusion of the fumigant into the packages they specify the liners must be perforated. The percentage of the area of the liner that is perforated, formerly stipulated to be not less than 0.3%, was recently increased to be not less than 0.9%. In the present study MB diffusion was characterized in three low density polyethylene SO2-releasing liners (‘Smartpac’, Quimas S.A., Santiago, Chile, model PTCAM016, 40x50cm, 0.05mm in thickness, 7g sodium metabisulfite, http://www.quimas.cl): 1) 0.3% vent area (0.6cm round holes spaced 10cm apart); 2) 0.6% vent area (0.8cm round holes spaced 10cm apart); and 3) 0.9% vent area (1.0cm round holes spaced 10cm apart). SO2, emitted by paper SO2 generating sheets or in this case an SO2 releasing package liner, inhibits the growth of decay pathogens such as Botrytis cinerea and extends the storage life of table grapes. Activated to release SO2 by moisture when the grapes are packaged, the SO2 releasing liner is composed of a three layer laminate of lowdensity polyethylene films; an outer layer relatively impervious to SO2 diffusion, and middle layer containing sodium metabisulfite crystals, and an inner layer that permits SO2 diffusion into the liner contents. In addition, standard, highdensity polyethylene (HDPE) liners (95 x 60cm, 0.01mm in thickness) with 0.3 or 0.9% vented areas and a commercial dual release SO2 pad (Fresca Dual Release, Quimetal Industrial SA, Santiago, Chile) were also characterized in some tests. This is the standard packaging used by the Chilean Industry and similar to that used by grape exporters worldwide. Experimental Procedure and Results Two MB fumigation schedules specified for control of the Chilean mite, Brevipalpus chilensis, were applied to grape packages with a high-density polyethylene liners with perforated areas of 0.9% or with a SO2-releasing liners with perforated areas of 0.3, 0.6, or 0.9%. Package and chamber concentrations were measured repeatedly for up to three hours during MB fumigation at 4.4 or 6.0°C with a dosage 64mg.L-1 or at 26.7°C with a dosage 56mg.L-1. Diffusion was similar and rapid into the packages among all perforated areas. MB concentrations inside the packages were not less than 95% of those of the chamber atmosphere within 15 minutes. Calculated concentration x time products increased slightly but significantly when the vent area increased, but these were probably a result of small differences in MB concentrations among the chambers. After fumigation with an MB dosage 64mg.L-1 at 4.4°C and subsequent storage at 2.0°C, mean MB residue content in grapes from most packages 48h after MB fumigation was below the limit of quantitation of 0.002mg.kg-1. After fumigation with an MB dosage 56mg.L-1 at 26.7°C and subsequent storage at 2.0 °C, mean MB residue content in grapes from most packages 24h after MB fumigation was below the limit of quantitation. Discussion and Significance of the Study MB diffusion into grape packages occurred promptly and the influence of the composition of the liner or the perforated vent area within the range we examined was very small, and observed only in the first few minutes of fumigation. These results indicate MB diffusion into table grape packages with perforated polyethylene liners will be adequate to control pests of quarantine concern. MB residues declined very rapidly after fumigation (data not shown). 139 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 1. Methyl bromide (MB) exposures expressed as concentration times time products (CxT products) after fumigation for 2 h after an initial MB dosage of 64mg.L-1 at 6.0°C determined from the MB concentration of the chamber atmosphere (air) and from inside the center-most bag of packaged ‘Thompson Seedless’ table grapes. The packages had high-density polyethylene (HDPE) liner with a vented area of 0.9% of the liner surface area or an SO2-releasing plastic liner with perforations that comprised a vented area (VA) of 0.3, 0.6, or 0.9% of the liner surface area. CxT product (MB mg h L-1; ± SD)z Liner VA% Chamber atmosphere Inside package SO2-releasing 0.3 113.7 (±0.6) ab 106.9 (±0.6) a SO2-releasing 0.6 110.9 (±0.8) a 106.6 (±1.7) a SO2-releasing 0.9 115.1 (±2.0) b 110.8 (±2.6) b HDPE 0.9 120.5 (±1.7) c 118.0 (±5.0) c Values followed by unlike letters are significantly different according to Fisher’s LSD (P = 0.05). z MB concentrations in our experiments met the minimum chamber concentrations after 30 or 180 minutes of fumigation to control of Brevipalpus chilensis (USDA-APHIS 2013). We collected and report empirical measurements of MB gas concentration into table grape packages; further study into this subject should include modelling MB diffusion, particularly under commercial conditions. To model MB diffusion into packages, effusion of the gas through the perforations and mass transfer of the gas through the intact liner plastic itself should be determined, since it is conceivable a substantial portion of the MB present in the packages diffused through the liner rather than through the perforations. Almost all package liners used in produce packaging are composed of low-density polyethylene films. MB diffusion through the sulfur dioxide releasing, three-layer laminate of low-density polyethylene film included in the present study is unknown. With few exceptions, both high and low-density polyethylene films were highly permeable to MB (Gamliel, et al., 1998; Qian, et al., 2011). Most reached a 90% equilibrium in MB concentration very rapidly, usually in less than one hour at 20°C when used as barrier films in chamber studies (Gamliel, et al, 1998). Another variable is the influence of the number of exposed perforations, since presumably some would be occluded by the fruit or pressed against the interior walls of the box. Other influences include MB diffusion include sorption into fruit and packaging components, bulk gas movement, chamber leakage, and the effect of package palletisation on diffusion. In an alternative approach to characterize MB diffusion under commercial conditions, Walse et al., (2014) stated that determination of the relative contributions of fruit and packaging to overall MB sorption during fumigation, which would vary markedly in commercial fruit operations, is neither practical nor necessary. By simply quantifying the extent of MB sorption, measured directly as the loss of MB from the chamber headspace, the collective contribution of fruit and its packaging to sorption can be estimated, and the MB doses applied adjusted to meet minimum CxT product thresholds to control insects. Acknowledgements We thank Thomas Hanke of Quimas, Ltd Santiago, Chile for donation of materials, technical information about liners, and financial support of a portion of the research conducted at DFA of California. We thank Jane Tebbets for critical review of the manuscript. References Gamliel A, Grinstein A, Beniches M, Katan J, Fritsch J, Ducom P. 1998. Permeability of plastic films to methyl bromide: a comparative laboratory study. Pesticide Science 55: 141-148. Qian Y, Kamel A, Stafford C, Nguyen T, Chism WJ, Dawson J, Smith CW. 2011. Evaluation of the permeability of agricultural films to various fumigants. Environmental Science and Technology 45: 9711–9718. U.S. Department of Agriculture – Animal Plant Health Inspection Service. 2013. Treatment manual. Code of Federal Regulations. Title 7 Agriculture, Chapter III, Animal and Plant Health Inspection Service, Part 319. http://www.aphis. usda.gov/import_export/plants/manuals/ports/downloads/treatment.pdf POSTER PRESENTATIONS Walse SS, Myers SW, Liu Y-B., Bellamy DE, Obenland D, Simmons GS, Tebbets S. 2013. Postharvest treatment of fresh fruit from California with methyl bromide for control of light brown apple moth (Lepidoptera: Tortricidae). Journal of Economic Entomology 106: 1155-63. 140 7th International Table Grape Symposium ID 9 Postharvest conservation of ‘Crimson Seedless’ grapes as influenced by ethephon and abscisic acid application on field Maria Auxiliadora Coêlho de Lima1,*, Patrícia Coelho de Souza Leão1, Danielly Cristina Gomes da Trindade1 and Marcella Setúval Valentim2 Embrapa Tropical Semi-Arid, PO Box 23, 56302-970, Petrolina, Pernambuco State, Brazil, University of Pernambuco/Embrapa Tropical Semi-Arid * Corresponding author: Tel: 55 87 3866-3612 Email: [email protected] 1 2 Background and Aims Ethephon (2-chloroethylphosphonic acid) at véraison has been applied to improve colour in red grape cultivars, especially those grown in high temperature regions. However, the use of ethephon can result in faster loss of berry firmness and lower post-harvest conservation. Furthermore, there is a risk of residue in the berries. Hence, it is important to study other techniques to promote the beneficial effects of ethephon. As an alternative, the application of abscisic acid (ABA) during the phase of grape maturation has been studied. In the São Francisco River Valley, the most important area of table grape production in Brazil, Crimson Seedless is one of the main cultivars. This cultivar demands techniques to give uniform and intensify the colour of the berries. However, the use of plant growth regulators has resulted in non-reproductive responses when the productive cycle is carried out during the second semester of the year, characterised by high temperatures. The aim of this study was to evaluate the effect of different concentrations and time periods of application of ABA, in comparison to ethephon and to the control, on postharvest conservation of ‘Crimson Seedless’ grapes produced in the São Francisco River Valley. Experimental Procedure and Results The study was conducted in a ten-year-old commercial vineyard in Petrolina, Pernambuco State, in São Francisco River Valley, Brazil. The vineyard was grafted on IAC 313 rootstock, trained in an overhead trellis system, with a spacing of 4.0m x 5.0m and drip irrigation. The management included fertilisation, diseases and pest control and other practices, recommended for the region. Pruning for production were carried out on 13 July 2012 and harvest periods began on 21 November 2012. Treatments consisted of two factors: ethephon (Ethrel® 720, 1 mL.L-1) and ABA (VBC 30101, ProTone®, 100g.L-1) applied pre-harvest and a time of storage. They included: control - no treatment; Ethephon; ABA, 400mg.L-1 at 14 days before harvest or 117 days after pruning (DAP); ABA, 200 + 200mg.L-1 at véraison or 97 DAP and 117 DAP; ABA, 400mg.L-1 at 97 DAP; ABA, 600mg.L-1 at 117 DAP; ABA, 300 + 300 mg.L-1 at 97 and 117 DAP; ABA, 600mg.L-1 at 97 DAP; Ethephon + ABA, 200mg.L-1 both of them applied at 97 DAP and Ethephon + ABA, 300mg.L-1 at 97 DAP. The treatments where ABA and ethephon were combined, two mixtures were prepared and applied, one for each of the products. The products were applied by manual spraying. After harvest, bunches in cardboard boxes were stored at 0.5ºC and 85% RH. The storage time evaluated was 0, 20, 27, 30 and 33 days. A randomised block experimental design, in a 10 x 5 factorial arrangement with four replications was used. Each plot had three bunches. The variables analysed were: weight loss; berry shrivelling; coverage and intensity of the red colour, according to a scale of notes where 1= 0%-25%; 2= 26%-60%; 3= 61%-90% and 4= 91%100%; pulp firmness; skin elasticity; soluble solids and sugars content; and titratable acidity. The berries were harvested when they attained commercial quality levels of total soluble solids, i.e. a minimum of 18° Brix in this study. The average value of titratable acidity was 0.44% as tartaric acid. During the storage time, weight loss, a light softening and an increase in titratable acidity were observed. Colour of berries was maintained during the study period. Ethephon and ABA pre-harvest application did not affect soluble solids and sugars content. But they influenced another characteristics related to the quality and postharvest conservation of ‘Crimson Seedless’ grapes. The weight loss was lower in bunches from treatments with ethephon combined with ABA or with the highest doses of ABA applied at véraison. On the other hand, the weight loss was doubled in the control and the ethephon treated berries. Some shrivelling was observed in berries at two applications of ABA 300mg.L-1 treatments. 141 POSTER PRESENTATIONS 7th International Table Grape Symposium Pulp firmness was lightly reduced during the storage. The comparison of treatments showed that berries of the control were firmer than berries of ethephon treatments, with or without ABA treatments. In general, skin elasticity had a gradual reduction. However, an abrupt change was observed after 30th days with the ethephon combined with ABA treatments. Finally, the higher coverage and intensity of the red colour was noticed at ethephon combined or not with ABA treatments and with the ABA 600mg.L-1 applied in a single dose. Discussion and Significance of the Study In conclusion, ethephon combined with ABA application had an effect on reducing the weight loss and promoting colour development of ‘Crimson Seedless’ grapes. This result can influence positively the quality and postharvest conservation of the grapes. However, other aspects need to be determined, including the data repeatability in other productive cycles, the legal permission to apply ABA in national viticulture and the commercial acceptance of the product. POSTER PRESENTATIONS 142 7th International Table Grape Symposium ID 10 Effects of Kelpak® Ecklonia maxima seaweed product on quality and yield of red globe table grape in Sicily, Italy Adriaan F Lourens1 and Giuseppe Tornello2,* Kelp Products International (Pty) Ltd., Box 325, Simon’s Town 7995, SOUTH AFRICA Coragro srl, Via R, Failla, 34-95042, Grammichele (CT), ITALY * Corresponding author: Tel: +390933942770, Email: [email protected] 1 2 Background and Aims The synthetic growth regulators gibberellic acid (GA), abscisic acid and cytokinins and natural biostimulants such as seaweed extract are commercially used to improve the quality and yields of table grapes. Kelpak®, an auxin-like seaweed product extracted from Ecklonia maxima, has been used with great success in improving table grape yields and quality in Australia, California, Chile, Egypt, Spain and South Africa. A field trial was conducted on Red Globe in Sicily, Italy to evaluate these positive effects in another important table grape producing region in Europe. Experimental Procedure The trial was conducted in 2012 using a Red Globe vineyard with plant spacing 2.8 x 2.8m in Licodia Eubea, Sicily, Italy. Kelpak® was applied as three treatments at different rates in 600 L water/ha, different timings and number of applications delivering a total of 12 L/ha for each treatment. The Kelpak® treatments were compared to an untreated control, as well as a positive control where GA was applied twice (BBCH 71 and 73) as per standard practice (Table 1). All Kelpak treatments received the GA treatment as well. Trial plots were 9 plants per replicate and each treatment were replicated six times in a randomized block design. Berry diameter, firmness, weight, colour, soluble solid content and bunch weight and cracking of berries were evaluated using standard procedures. Data were analysed for statistically significant differences (p=0.05, Student-Newman-Keuls). Table 1. Effect of Kelpak applications on quality and yield of Red Globe table grapes, Sicily 2012. Measurement GA x 2 71, 73 GA x 2 71, 73 ** 6L.ha-1 x2 75, 77 GA x 2 71, 73 ** 4 L.ha-1 x3 71, 73, 75 GA x 2 71, 73 ** 3 L.ha-1 x4 71,73,75,77 Untreated control Berry size (mm) 26.8c 27.5b 27.0c 28.0a 23.4d Berry weight (g) 10.2c 10.8ab 10.5b 11.0a 8.5d Berry firmness 2.0c 2.5b 2.6ab 2.7a 1.8d Soluble solids (ºBrix) 14.8d 15.5b 15.1c 16.1a 15.4b Colour (lower value = best) 2.6a 1.8b 1.8bc 1.6cd 1.6d 1282b 1307b 1295b 1408a 1134c * Bunch weight (g) * ** * BBCH scale for application stages of GA Rate and BBCH scale for application stages of Kelpak® Values with different letters differ significantly at the 95% confidence level * ** Results and Discussion 7th International Table Grape Symposium 143 POSTER PRESENTATIONS Kelpak foliar spray at 3L in 600L water/ha applied at BBCH 71, 73, 75 and 77 was the best treatment, with significant improvement in berry size, firmness, weight and sugar content, bunch colour and weight compared to the GA control (Table 1). The second best treatment was Kelpak at 6L.ha-1, applied after GA applications at BBCH 75 and 77. It was significantly better than the GA control in berry size, firmness, weight, sugar content and bunch colour. Kelpak at 4L.ha-1 applied at BBCH 71, 73 and 75 was still better than the GA control in berry firmness, weight, sugar content and bunch colour and similar in berry diameter and bunch weight. The GA control was better than the untreated control in all variables except sugar content and colour, where the untreated control had better values. Compared to the GA control, the combined benefits from the use of the Kelpak 3L X 4 treatment were a 10% improvement in total yield, an increase in berry size and bunch colour and, as a consequence, a higher proportion of the fruit meeting export class standards with increased value per box. None of the treatments showed any visual signs of phytotoxicity and berry cracking was absent in all treatments. Significance of the Study The data obtained in this trial is a confirmation of previous reports describing improved table grape yields and quality from Kelpak trials in California (Bauer, 2001; Keathley, 2002), Chile (Orellana, 2007) and South Africa (Lombard, 2007) and provides evidence that Kelpak can be a useful tool to improve returns in table grapes grown in a major production area in Italy. References Bauer B. 2001. Kelpak for yield and growth enhancement of Ruby Seedless table grape. Research report, 5 pages. Two Bees Agricultural Research, 20592 Ayres Ave, Escalon, California. Keathley JP. 2002. Grape yield increases following application of Kelpak sprays. Research report, 9 pages. Caltec Research and Development Company, 1420 F St, Modesto, California. Lombard PJ and Lourens AF. 2007. The use of Kelpak, a natural liquid seaweed extract as a tool for improving table grape quality in South Africa. Poster presentation, 5th International Table Grape Symposium, Somerset West, South Africa. Orellana J. 2007. Effects of an auxin based product extracted from the seaweed Ecklonia maxima on berry quality and post-harvest behavior in table grapes in Chile. Oral presentation, 5th International Table Grape Symposium, Somerset West, South Africa. POSTER PRESENTATIONS 144 7th International Table Grape Symposium ID 11 Policy assessment for the table grape production in southern Italy Umberto Medicamento1,*, Arturo Casieri1 and Michele Fioretti2 Department of Agricultural & Environmental Science, University of Bari – Aldo Moro, via Amendola 165/A, Bari, ZIP CODE: 70126 – Italy 2 Agriproject Group srl. Via delle Orchidee, 20 - 70018 Rutigliano (BA), Italy * Corresponding author: Tel. +39.080.544.2968, Email: [email protected] 1 Background and Aims Table grape production is very important in the Southern Italian food sector. The Puglia region is a major contributor with production mainly located in the province of Bari. Although farmers living in this area have a long tradition in table grape cultivation, there is a strong need for public intervention and private initiative in order to set up a new organizational framework which is able to enhance competitiveness of the table grape industry. There is a striking need for both technical innovation and adoption of new varieties to cover a wide range of situations. This must take into account the new, 2014-20, European Agricultural Policy. In this paper we focus over local public intervention simulating scenarios and their effects on farmers’ income. To accomplish this objective we use the RFM methodology explained below. Experimental Procedure and Results The method used to measure the policies’ impacts on table grape cultivation is based upon the definition of the Representative Farm Models (RFM) characterized for having different allocation of production factors and technological levels. RFM provides a very useful platform to evaluate the relationship between technical innovation, profit level, and consequent policy impact. Data were collected by directly interviewing a panel of experts selected upon their reputation and long-term experience in table grape cultivation. Results offer interesting insights for both policy makers and private organizations (e.g. farmers’ associations, lobbyists). Discussion and Significance of the Study Results show that interventions from policy makers should be ‘tailored’ to take into account data from RFM studies as alternative to ‘one-fit-all’ interventions. Also, policy makers should foster organizational innovation to reach efficiency through flexible coordination of a wide set of activities between farmers and other stakeholders. Acknowledgments The authors are thankful to the Province of Bari, namely the Office for Agricultural Resources, for providing support to the research development. References Casieri A; Roma R; Cimino O. 2010. Measuring effect of a demand shift on the sustainability of table grape production in Apulia Paper prepared for presentation at the 119th EAAE Seminar ‘Sustainability in the Food Sector: Rethinking the Relationship between the Agro-Food System and the Natural, Social, Economic and Institutional Environments’, Capri, Italy, June, 30th – July, 2nd, 2010. Casieri A, De Gennaro B, Medicamento U. 2008. Framework of economic institutions and governance of relationship inside a territorial supply chain: The case of organic olive oil in the Sierra de Segura (Andalusia) Cahiers Agricultures n° 17. De Benedictis M, Cosentino V. 1979. Economia dell’Azienda Agraria. Il Mulino. Bologna. Marenco G. 2005. Lo Sviluppo dei Sistemi Agricoli Locali: Strumenti di analisi delle Politiche. ESI. Napoli. Nelson RR and Winter SG. 1982. An Evolutionary Theory of Economic Change. The Belknap Press of Harvard University Press. Cambridge, Massachussetts, and London, England. Simon HA. 1972. From Substantive to Procedural Rationality. In C.B. McGuire and R.R. Radner, Decision and Organization, Amsterdam, North-Holland. 145 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 12 Effect of rootstock on growth and nutritional status of Thompson Seedless grown under soils with different air content Michelle Morales1,*, Raúl Ferreyra2, Manuel Pinto1 and Gabriel Sellés2 1 Centro de Estudios Avanzados en Fruticultura (CEAF), Rengo, Chile, 2 Instituto de Investigaciones Agropecuarias (INIA), Santiago, Chile * Corresponding author: E-mail: [email protected] Background and Aims Table grapes are grown in a wide range of soil types, thus, often are cultivated under an inappropriate water to air ratio in soil, limiting productivity and fruit quality (Selles et al., 2012). Almost 22% of total Chilean table grapes are growing in soils with less than 15% of air capacity (AC), (Ferreyra, 2009). It has been reported that both vigour, production and fruit quality in scion are strongly affected by rootstock variety used (Dalbó et al., 2011). The aim of this investigation was to determine the effect of rootstock on growth and nutritional state of Thompson Seedless (TS) grown under soils with different air content. Experimental Procedure and Results This work was undertaken during the 2008-2010 seasons. The study were carry out in 150L pots, filled with sandy loam (Fa) and silty loam (Fl) soils to generate different air capacity (AC); AC= 15% in sandy loam and AC= 10% in silty loam. We used Thompson Seedless variety grafted on five rootstocks (110 Richter, Harmony, Freedom, Ramsey, 1616 Couderc) and a control (Thompson S. ungrafted), planted during the 2007/08 season. The pruning weight, chlorophyll content and mineral nutrient status were evaluated. To determine mineral nutrient status (N as NO3, P, K, Ca, Mg, Mn, Cu, Zn), grapevine petioles from each experiment (three replicates) were used. The results showed an interaction between soil air contents and rootstocks. In soils with low aeration, control plants had lower pruning weight than grafted plants, and plants grafted on 110 Richter and Freedom rootstocks had more growth. The chlorophyll content decreased with low aeration of soil and was correlated with low nitrogen content in the petioles. Plants grafted on Harmony and Freedom rootstocks had 30% higher levels of potassium content in petiole than control plants. The interaction between rootstocks and soil air contents showed than 110 Richter had 56% higher nitrogen content in petioles of plants grown with low soil aeration, while plants grafted on Ramsey had higher nitrogen in soils with good aeration. Discussion and Significance of the Study The roostocks had an effect on grafted Thompson Seedless and there was an interaction with soil aeration. Rootstocks improved the plant growth compared with ungrafted plants. On the other hand, in soils with aeration restriction (fine textures), the nitrogen content decreased in plants grafted with Ramsey and ungrafted (control). These combinations had more nitrogen content than Richter 110 in soil with fine textures. This could be associated with higher growth. In conclusion, the use rootstocks for Thompson Seedless improves growth and nutrient status of plants in soils with low air content. Moreover, fertilizer regimes should be adjusted according to the rootstock used, especially in regard to fertilization with nitrogen and potassium to improve Thomson Seedless quality and determine appropriate standards for the variety. Acknowledgements Acknowledgments: Grant N° 05CR11PAT-11, INNOVA- CORFO. References Dalbó MA, Schuck E, Basso C. 2011. Influence of rootstock on nutrient content in grape petioles. Revista Brasileira de Fruticultura 33: 941-947. Ferreyra BR. 2009. Caracterización de las propiedades físicas de suelo en el cultivo de la uva de mesa en la V Región de Chile. Facultad de Cs. Agronómicas. Tesis Ing. Agronomo, Universidad de Chile, Santiago, p. 42. POSTER PRESENTATIONS Selles G, Ferreyra R, Ruiz R, Ferreyra BR, Ahumada, R. 2012. Compactación de suelo y su control: Estudio de casos en el Valle de Aconcagua. In: Selles, G., Ferreyra, R. (Eds.), Boletín INIA N° 234. Instituto de Investigaciones Agropecuarias INIA-La Platina, Santiago, Chile, p. 54 p. 146 7th International Table Grape Symposium ID 13 Use of ABA to improve the colour of Red Globe table grapes in the San Juan region, Argentina MF Mujica1,*, F Montenegro2 and MB Pugliese1 INTA E.E.A. San Juan. Argentina. Calle 11 y Vidart. Villa Aberastain. Pocito. San Juan. Argentina Facultad de Ingeniería - Universidad Nacional de San Juan. Argentina * Corresponding author: Tel: +54 264 4921079 E-mail: [email protected] 1 2 Background and Aims In Argentina there are 217,750ha cultivated with vines, of which 12,179ha are used for table grapes. The province of San Juan is a national leader in the production of fresh grapes for both external and internal markets, producing about 82% of the grapes exported from the country with Red Globe the most popular variety. One of the most important parameters in terms of quality is the colour intensity of Red Globe. In the Valley of Tulum, located in the province of San Juan, environmental constraints influence the colour synthesis (the colour desired in most cases is not obtained due to climatic factors), despite the excellent levels of other quality attributes achieved in each season in terms of soluble solids concentration and size for this variety. The application of growth regulators is used as a management practice to achieve increases in the intensity of colour of red varieties. Ethephon, which is widely used on red varieties, is known to be a promoter of senescence, leading to risks associated with negative effects on quality as it may induce fruit drop and produce berry softening at maturity and during storage. Also, current treatments of 0.7ppm ethephon appear to be becoming less effective, resulting in the need to find alternatives for obtaining higher colour in grapes. More recently Abscisic Acid (ABA) has been used to promote colour development in red grape varieties. ABA has been shown to control stomatal closure, reduce vegetative growth and induce the synthesis of phenolic compounds in berries. During berry development, ABA levels in the skins increases markedly, suggesting a possible role of ABA in the control of berry development. With this background, trials of a commercial ABA product, ProToneR, applications were conducted at different times and at different concentrations with the aim to improve the colour of Red Globe grapes produced in the province of San Juan. These tests were conducted for three seasons to obtain information to register ProToneR for used in Argentina. Experimental Procedure and Results Experiments were conducted on different farms with varying agro-climatic characteristics in the 2011-2012 season (3 farms) and the 2012-2013 season (5 farms). Treatments were applied in a randomised design. ABA treatments included applications of 400ppm of ProToneR, or 200ppm of ProToneR three weeks after véraison (50% softened berries) plus an application of 200ppm of ProToneR or 400ppm of ProToneR, 10 days before harvest; standard ethephon only treatment or an untreated control. The use of ABA did improve berry colour (purple red hue) of the Red Globe variety. In particular, the treatment with two applications of 400ppm ABA produced significant differences with earlier colour development and hues tending to red-purple, regardless of the agro-climatic zone. Because the visual aspect is a feature that strongly influences the marketing of Red Globe, ABA provides a promising alternative product to assist growers to optimise berry colour and the commercial value of the product from the variety. However, it should be noted that berries from control vines had higher luminosity (L), measured as greater brightness and chroma (more vivid colours). In regard to berry firmness at harvest it was observed that applications at véraison reduced firmness more than other dates of application. Applications made 10 days before harvest had the least effect. The highest concentration of ABA at 400ppm reduced firmness more than Ethephon or the lower concentrations of ABA. Other quality parameters such berry size (polar and equatorial diameter of the berries), titratable acidity, fresh bunch weight and berry weight were not altered with the application of ABA, while the soluble solids content was affected slightly. Results from the third season are being processed in order to finish the first stage of experimentation to provide information to register ProToneR for commercial use in Argentina. 147 POSTER PRESENTATIONS 7th International Table Grape Symposium Acknowledgements The work was financially supported by INTA and Valent Biosciences. The authors appreciate the cooperation of the growers in whose vineyards the trials sites were located. References Baigorri H, Antolin C, De Luis I, Geny L, Broquedis M, Aguirrezábal F, Sánchez-Díaz, M. 2001. Influence of training system on the reproductive development and hormonal levels of Vitis vinífera L. cv. Tempranillo. American Journal of Enology and Viticulture 52: 357-363 Ban T, Ishimaru M, Kobayashi S, Shiozaki S, Goto-Yamamoto N and Horiuchi S. 2003. Abscisic acid and 2,4-dichlorohenoxyacetic acid effect the expression of anthocyanin biosynthetic pathway genes in ‘Kyoho’ grape berries. Journal of Horticultural Science and Biotechnology 78: 586-589. Bergqvist J, Dokoozlian N, Ebisuda N. 2001. Sunlight exposure and temperature effects on berry growth and composition of Cabernet Sauvignon and Grenache in the Central San Joaquin Valley of California. American Journal of Enology and Viticulture 52:1-7. Blommaert KL, Hanskom A, Steenkamp N. 1975. Improved colour development of Barlinka grapes with ethephon. The Deciduous Fruit Grower 25: 297-299. Blommaert KL and Steenkamp J. 1977. Growth regulators: More applications for table grapes. Deciduous Fruit Grower 27: 350-352. Boneh U, Bitona I, Schwartzb A, Ben-Aria, G. 2012. Characterization of the ABA signal transduction pathway in Vitis vinífera. Plant Science 187: 89–96. Boo O, Saito T, Tomitaka Y. 1997. Effect of plant growth regulators on the anthocyanin synthesis of Perilla ocymoides L. Korean Journal of Horticultural Science and Technology 38, 9-14. Callejas, R. 2005. Incremento del colour de variedades rojas. Centro de estudios de la vid. Universidad Nacional de Chile. [En línea] [http://www.cevid.uchile.cl/articulos/ColourdeCubrimientoVarRojas.pdf ], [Consulta: 10 de enero 2012]. Cantín C, Fidelibus M, Crisosto C. 2007. Application of abscisic acid (ABA) at veraison advanced red colour development and maintained postharvest quality of “Crimson seedless” grapes. Postharvest Biology and Technology 46: 237-241. Fidelibus, MW. 2005. Use of ABA to improve the colour of table grapes. Department of Viticulture and Enology, University of California, Davis. Peppi MC, Fidelibus MW, Dokoozlian NK. 2006. Abscisic acid application timing and concentration affect firmness, pigmentation, and colour of ‘Flame Seedless’ grapes. HortScience 41: 1440-1445. Peppi MC, Fidelibus MW, Dokoozlian NK. 2007. Application timing and concentration of abscisic acid affect the quality of ‘Redglobe’ grapes. Journal of Horticultural Science and Biotechnology 82: 304-310. Peppi PorfirI H. 2000. Manejo productivo de la uva de mesa y su efecto sobre la calidad- Análisis crítico. En: Calidad y condición de llegada a los mercados extranjeros de la uva de mesa de exportación chilena. Pontificia Universidad Católica de Chile. Chile. p.17-28. Peppi MC and Dokoozlian NK. 2003. Influence of chemical treatments at véraison on the pigment content and composition of table grapes. American Journal of Enology and Viticulture 53: 259A. Peppi MC and Fidelibus MW. 2008. Application, timing and concentration of abscisic acid or ethephon and their effects on colour of Crimson seedless table grapes. Acta Horticulturae 774: 173-177. POSTER PRESENTATIONS 148 7th International Table Grape Symposium ID 14 Potential to enhance fruit quality of table grapes with potassium sorbate and cincturing David R Oag* and Allan D McWaters Horticulture and Forestry Science, Department of Agriculture Fisheries and Forestry, Applethorpe, Queensland, 4380, Australia * Corresponding author: Tel. +61 7 4681 6147, Email: [email protected] Background and Aims A new black seedless grape variety, M1301 , which was developed in Australia, is being grown in most production regions. Fruit meeting quality specifications is marketed as Magic Seedless®. It is recognised for its black berry with a crisp texture and naturally good colour development in subtropical growing conditions. In some seasons, the fruit will struggle to ripen to more desirable sugar concentrations (i.e. >16°Brix) sought in the Australian market. Gabler et al., (2010) reported four applications of potassium sorbate during berry growth significantly increased soluble solids of Red Globe berries in a temperate environment. A pilot study was undertaken (2010) in a table grape vineyard at Emerald to ascertain the potential for foliar applications of potassium sorbate to increase the soluble solids and enhance fruit quality (colour, berry firmness) of Magic Seedless®. Cincturing at véraison is the recommended practice for enhancing ripening of the variety and was included in the study. Experimental Procedure and Results The trial consisted of three replicate plots per treatment with four vines per plot and data collected from the middle two vines. Treatments were (1) untreated Control; (2) 2mm cincture at véraison; (3) potassium sorbate – two sprays before véraison (Early); (4) potassium sorbate – two sprays after véraison (Late) and (5) potassium sorbate – four sprays (Early & Late). Potassium sorbate (Sigma–Aldrich) sprays were applied to the bunch zone (bunches and leaves) at the equivalent of 1.3gL-1 potassium per vine. Bunches were sprayed to runoff using a knapsack sprayer. Applications were at approximately 12 day intervals starting (13 October) approximately 3 weeks before véraison. Fruit yield per vine (weight and bunch number) was recorded at harvest (1st December) and a berry sample collected per replicate for quality assessment – soluble solids (°Brix) and titratable acidity. Twenty berries per replicate were individually analysed for berry firmness (Instron 5543, 3mm diameter probe, 500N load cell), berry weight and berry colour (Konica Minolta CR400 colourimeter). Table 1. Influence of cincturing and bunch-directed potassium sorbate sprays on fruit quality of Magic Seedless®. Treatment Soluble solids (°Brix) Sugar yield (kg/vine) Berry firmness (Newtons)1 Control 13.7 1.035 0.860 Cincture 14.8 1.128 1.147 Early 13.8 0.920 0.868 Late 14.5 1.026 1.059 0.758 0.790 Early & Late 14.1 Berry firmness = maximum compressive load 1 Cincturing and postassium sorbate applied after véraison increased the soluble solids of Magic Seedless® berries (Table 1). In the case of cincturing the increase was 8% over the control. The important fruit quality parameter of berry firmness was also increased by cincturing or potassium sorbate applied after véraison. Cincturing and potassium sorbate applied during ripening produced slightly darker berries (L*) than the control (Table 2). All potassium sorbate treatments appear to produce marginally deeper blue colour (b*). 149 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 2. Skin colour of Magic Seedless® berries following potassium sorbate sprays and cincturing. Treatment L* a* b* Control 27.226 1.835 0.224 Cincture 26.482 1.590 0.237 Early 27.147 1.786 0.198 Late 26.928 1.645 0.189 Early & Late 27.063 1.836 0.208 L* indicates the lightness of colour (0 = black; 100 = white) Discussion and Significance of the Study The positive effect of the recommended practice to cincture vines at véraison to improve Magic Seedless® fruit quality was confirmed. Applications of potassium sorbate from véraison indicated the potential to enhance ripening and fruit quality. A more detailed study is required to refine the most effective application times and rates of potassium sorbate, as well as the effectiveness relative to cincturing. The shorter period between véraison and harvest in a subtropical environment may limit the time available for the full affect of foliar applied potassium sorbate to occur. Cincturing is a labour intensive operation. Foliar sprays are easy to apply and may provide cost savings whilst enhancing fruit quality. Acknowledgements The cooperation of Mr Joe Cordoma, Cordoma Farms, Emerald, with the field trial is greatly appreciated. References Gabler FM, Margosan DA, Smilanick JL, Hashim-Buckey J. 2010. Influence of cluster-directed applications of potassium before harvest on the quality of table grapes. 6th International Table Grape Symposium, 24-26 June 2010, University of California, pp 46-49. POSTER PRESENTATIONS 150 7th International Table Grape Symposium ID 15 Temperature and light regimes under different plastic rain covers David R. Oag* Horticulture and Forestry Science, Department of Agriculture Fisheries and Forestry, Applethorpe, Queensland, 4380, Australia. Tel. +61 7 4681 6147, Email: [email protected] Background and Aims Plastic vine covers are used to protect fruit from rain damage during the ripening period. The use of plastic vine covers is becoming increasingly common in the early-ripening table grape industry in Queensland. All the plastic covers commercially available in Australia are opaque and consequently create a level of shading of the vine canopy. In Queensland, the plastic covers are installed for a period of 3-4 weeks, coinciding with the relatively short ripening period. Following the introduction of plastic vine covers, anecdotal reports emerged of delayed harvest time, reduced colour development in red varieties, leaf scorch and condensation beneath the plastic. Reduced fruitfulness the following season has also been speculated to be a consequence of the use of plastic covers. This is highly unlikely in Queensland as the period of floral initiation occurs much earlier in the season (Oag, 2001) and long before plastic vine covers are installed. A delay in harvest time could arise from the impact on photosynthesis of the change in temperature environment and light levels beneath the plastic. Data detailing the impact of plastic covers on the climate within the vine canopy is not available. An opportunity arose in the 2010/11 season to quantify temperature and light levels below three plastic covers of different light transmission. Experimental Procedure and Results Three types of plastic vine cover were examined in a field trial at St George, Queensland. Vines were grown on a large Y-trellis and each type of plastic was installed over a single row of vines. The plastic was supported above the vine canopy by a wire (Figure 1) and attached to a foliage wire at the side of the canopy. Temperature beneath the plastic was recorded continuously using temperature dataloggers (Tinytag, Hastings Dataloggers) hung immediately below the plastic (ie ‘roof’) and from the cordon wire (Figure 1). The plastic covers were of different translucency. Two commercially available opaque, white plastic covers (Grape Cover and Aperio Grape Cover Plus) were rated at 50% and 60% shade, respectively, whereas a new ‘clear’ plastic was rated at 80% light transmission. Light levels measured as photosynthetically active radiation (PAR) were recorded using a ceptometer (DeltaT, USA). The ceptometer was positioned immediately beneath the plastic cover, avoiding any shading from the vine canopy, and above the canopy between vine rows where total incoming light (PAR) was measured. Figure 1. Temperature sensors positioned immediately below the plastic cover ie ‘roof’ (left) and at the cordon height. 7th International Table Grape Symposium 151 POSTER PRESENTATIONS The opaque white plastic covers considerably reduced the amount of light (PAR) reaching the vine canopy (Table 1). The relatively low light levels could have an impact upon the rate of photosynthesis at a time when the vine is ripening fruit. At 75-80% light transmission through the ‘clear’ plastic it could be expected photosynthesis would continue largely unaffected. A further study to collect harvest data is required to determine how the different plastics affect harvest time and sugar concentration. Table 1. Incoming total PAR measured above the vine canopy and PAR measured below each type of plastic expressed as percent transmission. Light (PAR) measured immediately before harvest. Light measurements 15/12/2010 Plastic type Total PAR (µmol.m-2.s-1) Transmission (%) Grape Cover 1752 35.2 Aperio Grape Cover Plus 1796 45.2 new “clear” plastic 1863 73.3 Figure 2. Air temperature beneath the Aperio Grape Cover Plus. Positions of temperature sensors were immediately below the plastic ie ‘roof’ (blue, 359592), cordon (green, 359585) and open (black, 55912). Figure 3. Air temperature in the ‘roof’ beneath the Grape Cover (346533, black) and Aperio Grape Cover Plus (359592, blue) compared to out in the open (green, 55912). Discussion and Significance of the Study The ‘clear’ plastic cover has two potential advantages over the opaque white plastics, namely greater light transmission and less extreme temperatures below the plastic cover. Shading by the opaque plastics is likely to dramatically impact photosynthesis during the important ripening period. Acknowledgements The cooperation of Peter Haslem, Sandilands Vineyard, St George with the field trial is gratefully acknowledged. References POSTER PRESENTATIONS Oag DR and Shaw RG. 2001. Characterising floral initiation and developing management strategies to maximise bud fruitfulness in subtropical table grape vines. Final report, FR01002. Horticulture Australia Ltd.19 pp. 152 7th International Table Grape Symposium ID 16 Flame Seedless cluster quality according to bud position M Cecilia Peppi*, R Callejas, E Kania and JL Henriquez Universidad de Chile, Facultad de Ciencias Agronómicas * Corresponding author: Tel: 56-2-2978 5727 Email: [email protected] Background and Aims Table grape quality includes cluster size, shape, uniformity and size of berries. Most pruning choices are established to account for differences in the bud fertility along the mature, dormant shoot without consideration of the potential impact of bud position on cluster quality. Some previous work in northern regions of Chile (Benavente et al., in press; Callejas et al., 2013) has shown differences in cluster shape and berry size depending on bud position and cultivar. Berry size is strongly related to berry number and flower number per cluster, and these factors can contribute to final quality (May, 2000). Spherical, conical or cylindrical clusters have different potential quality, with cylindrical clusters having fewer berries per cluster, smaller berry size and therefore lower yields. The aim of the present study was to determine the cluster quality of Flame Seedless according exclusively to bud position with equal bud numbers retained per plant. Experimental Procedures and Results The trial was established during 2011-2012 in a commercial vineyard in Buin, Región Metropolitana, Chile. There were 3 treatments, which consisted of retention of shoots arising from 2 buds/cane (pruning element) but at different positions of origin along the cane. To establish the different treatments, immediately after bud break shoots on basal buds were discarded and only shoots arising from the two distal buds on each pruning element were retained. The treatments were T1, which used only buds 5 and 6 on the cane, T2 which used buds 3 and 4 and T3 which used buds 1 and 2. Five elements of each treatment were randomly selected on each vine. Common cultural practices for the Flame Seedless cultivar were applied to all treatments. These included cluster berry thinning and applications of plant growth regulators. The statistical design was a completely randomized block, with 10 replicates. The block corresponded to a vine, and the 5 pruning elements per treatment were the experimental unit. During the season, bud break, cluster shape immediately after fruit set, berry weight and berry diameter were evaluated. All clusters were harvested at commercial maturity. Results were analysed by ANOVA. Significant differences were separated using.LSD (5%). The results showed that there were no significant differences in cluster number per shoot between treatments. Clusters from buds 5 or 6 (T1) were longer than clusters from the base of the cane (T3) when measured before berry thinning, when berries were approximately 14 mm in diameter. T1 (buds 5 and 6) had less cylindrical clusters than T2 and T3. Berry diameter in this trial was similar between treatments, but berry weight from distal buds was slightly higher. Soluble solids were the same regardless of cluster origin, but basal positions had higher acidity. Discussion and Significance of the Study Buds closer to the base of pruning elements may have less potential to produce quality fruit. However, in this study differences in fruit quality from varying bud positions were minimal in terms of fruit marketability, as also reported previously with Flame Seedless (Callejas et al., 2013). Furthermore, pruning to longer elements where they must be tied to the trellis is more expensive and may not justify the small gains from a higher price obtained for fruit with bigger or heavier berries. Location and vineyard status can under some circumstances show quality differences related to bud position, but the main distinction between different pruning strategies should be the ability to choose better clusters in terms of shape, berry number, berry size and potential total yield. Acknowledgements The authors acknowledge funding by Conicyt, through the Programa de Atracción e Inserción de Capital Humano Avanzado, project 79100012. References Benavente M, Callejas R, Reginato G, Peppi,C. Effect of crop load and cluster thinning according to its shape on cluster weight and yield on ‘Thompson Seedless’ table grapes. Acta Horticulturae (in press). May, P. 2000. From bud to berry, with special reference to inflorescense and bunch morphology in Vitis vinifera L. Australian Journal of Grape and Wine Research 6:82-98. 7th International Table Grape Symposium 153 POSTER PRESENTATIONS Callejas R, Benavente M, Toro B, Peppi, C. 2013. Adaptación de la poda y ajuste de carga para maximizar los rendimientos de uva de mesa. Rev. FCA UNCUYO 45(2): 129-139. ID 17 Development of ProtoneTM SL (10% s-ABA) for colouration of red seedless table grapes in Europe Michael Schröder*, Roy McCormick, David Parron Ojeda and Robert Fritts Jr Valent BioSciences Corporation, 870 Technology Way, Libertyville, IL 60048, USA * Corresponding author, Tel: +49 7584 922949, Email: [email protected] Background and Aims Hot climates are most suitable for the production of high quality table grapes but when colouring conditions are unfavourable due for example to high temperatures, red grape cultivars have difficulties to develop colour (Fukushima et al., 1990; Cantin et al., 2007). Lack in colour is generally leading to significant price reductions and higher harvest costs for the grower. Abscisic acid (s-ABA) is a relatively small sized 15-carbon weak acid that occurs naturally in plants and in some fungi (Cutler and Krochko, 1999). Since the 1970s it has been known to increase red colour development by accelerating anthocyanin accumulation in the skin of maturing red grape berries (Ban et al., 2000). Valent BioSciences Corporation (VBC) conducted first development studies with s-ABA for grape colouring in the USA in 2003. Early studies used s-ABA as a technical active substance (a.s.) and tested various formulations in small plot trials. From 2008, a 20% s-ABA water soluble granule (SG) formulation was registered under the trade name ProTone in California and three years of large-scale commercial studies followed. Eleven years later ProTone is now registered for grape colouring in Chile, Egypt and Peru as a 10% soluble concentrate (SL) formulation and in Australia, Israel, Lebanon, Mexico, South Africa and the USA for the SG formulation. In the majority of the table grape studies undertaken outside of Europe, s-ABA was most effective when applied at or shortly after véraison using dose rates of ~ 40g a.s.hL-1 (Peppi and Fidelibus, 2008). Under difficult colouring conditions more than one application of s-ABA was required. The application method had to provide good coverage of the grape clusters as s-ABA is not translocated to any extent within the plant (Gu et al., 2011). Despite a good understanding of the use recommendations of ProTone the existing data base was not sufficient for justifying either the optimum number of applications or spray intervals which is a regulatory requirement in Europe (EU). Consequently, additional efficacy studies had to be conducted to be able to obtain commercial registrations. In the meantime, s-ABA was included under Annex I and IV listings during 2014, thus it is the intention of VBC to support zonal registrations within the EU in the near future. Experimental Procedure Between 2010 and 2013, 27 efficacy and crop safety studies were undertaken with ProTone (SL, 10% s-ABA) on commercially grown ‘Crimson Seedless’ or ‘Red Globe’ table grapes in Greece, Italy and Spain. Studies were designed as either ‘dose justification’ (DJ) studies or ‘timing’ (T) studies. The majority of studies in Spain included ethephon as a comparison treatment. All vines were selected for homogenous growth and crop load. In the DJ studies ProTone was applied once at dose rates of 10, 20, 30, 40 or 80g a.s.hL-1 to determine the most effective dose for grape berry colouring. The applications were conducted at véraison when 90% of the berries were soft and ~20-30% began to develop colour. The T studies determined the most effective application timing and application number. T studies tested ProTone at a dose rate of 40g a.s.hL-1 applied one to three times as described in the tables below. The 80 g a.s.hL-1 dose rate was applied three times and was tested for crop safety purposes only. All studies used spray water volumes of 800-1,000L.ha-1 using hand held sprayers designed to simulate commercial spray applications. Plots were harvested by hand. Picking dates were based on two quality parameters (1) berry colour as aimed by these efficacy studies and (2) total soluble solids (TSS). Grape cluster colour was determined in the studies using a colour chart with 1 to 4 colour classes. ‘Marketable’ yield was defined as clusters harvested with a colour from 1 to 3 while meeting minimum TSS content (17º Brix according to in-country market requirements). ‘Unmarketable’ yield included clusters that never developed colour and also partly coloured clusters which could be sold as a class II or III product but at a considerably lower price. The quality parameters acidity (g tartaric acid/L) or berry firmness (N) were additionally measured. Yield in the year following the application was determined as number of fully developed clusters/vine. POSTER PRESENTATIONS 154 7th International Table Grape Symposium Results and Discussion One application of ProTone at the 40g a.s.hL-1 dose rate showed excellent efficacy on berry colouring and consequently on marketable yield (Table 1). The 40g a.s./hL dose rate doubled the mean total marketable yield per vine and increased the mean amount of fruit per vine in the first pick by 7.6kg when compared to the untreated control (UTC). Lower concentrations of ProTone were clearly less effective. If more berry colour is required an application strategy based on multiple applications should be considered as shown for the T studies below. Table 1: Yield parameters in the DJ studies after one application of ProTone. Yield parameter UTC ProTone (g a.s.hL-1) 10 20 30 40 10.6 14.7 17.1 18.9 22.9 Total yield (kg/vine) Mean value (n=5-8) 39.1 41.8 38.6 36.4 39.1 Marketable* yield (% of total yield) Mean value (n=5-8) 27% 35% 44% 52% 59% Marketable* yield in the 1st pick (kg/vine) Mean value (n=5-8) 1.0 2.0 5.1 6.6 8.6 Marketable* yield (kg/vine) Mean value (n=5-8) Marketable yield based on grading clusters into colour classes 1-4 while meeting a minimum TSS content. * Based on the T studies, the efficacy increased with the number of applications reaching 82% mean marketable yield of the total yield at three applications (Table 2). One application at the early timing A (when 5% or less berries began softening) was less effective for berry colouring when compared to the application at veraison (B). Differences between application timing A or B disappeared if multiple applications were conducted. Table 2: Yield parameters in the T studies*. Yield parameter UTC ProTone (40g a.s.hL-1) A B AB BC ABC BCD Marketable yield in kg/vine Mean value (n=4-8) 12.0 20.4 25.1 30.9 29.2 33.0 27.2 Total yield (kg/vine) Mean value (n=4-8) 38.3 47.4 43.0 48.7 37.4 40.3 33.2 Marketable** yield (% of total yield) Mean value (n=4-8) 31% 43% 58% 64% 78% 82% 82% Marketable** yield in the 1st pick (kg/vine) Mean value (n=4-8) 1.9 4.9 9.1 13.0 5.0 5.8 4.8 ** Application timings: A: When 5% or less berries began softening; B: At véraison: when 20-30% of berries began to develop colour; C: 2 weeks after application B; D: 2 weeks after application C. ** Marketable yield based on grading clusters into colour classes 1-4 while meeting a minimum TSS content. * One application of ProTone at the 40g a.s.hL-1 dose rate showed superior efficacy in the mean total marketable yield and the mean marketable yield at first pick when compared to one application of ethephon at 60g a.s.hL-1 (Table 3). Differences between both treatments were not always statistically significant in each study. However, ethephon applications are limited in Europe due to Maximum Residue Levels (MRLs). MRLs do not exist for ProTone and would allow multiple applications leading to even greater efficacy differences between both products. 155 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 3: Yield comparison between single ProTone and ethephon treatments in Spain. Yield parameter UTC Ethephon 60g a.s.hL-1 ProTone 40g a.s.hL-1 Marketable* yield (kg/vine) Mean value (n=5) 12.0 23.5 27.2 Total yield (kg/vine) Mean value (n=5) 52.6 51.9 52.0 Marketable* yield (% of total yield) Mean value (n=5) 23% 45% 52% Marketable* yield in the 1st pick (kg/vine) Mean value (n=5) 1.4 7.6 11.2 Marketable yield based on grading clusters into colour classes 1-4 while meeting a minimum TSS content. * There were no negative effects of ProTone on fruit quality (TSS, fruit firmness, cluster weight and acidity), total yield or the yield in the year following the application (Table 4 and 5). There was no phytotoxicity recorded at any rate or timing. Also multi-year applications (up to three years) on the same vines showed no negative effects on berry quality or yield even when applied three times per year at the 80g a.s.hL-1 dose rate (data not shown). Table 4: Effects on quality parameters (apart from colour) and return bloom in the DJ studies. Parameter Efficacy (treatment values as % UTC, where UTC = 100%) UTC (absolute values) Ethephon 60g a.s.hL-1 ProTone 10g a.s.hL-1 20g a.s.hL-1 30g a.s.hL-1 40g a.s.hL-1 80g a.s.hL-1 695 114 110 112 108 115 112 17.9 103 100 102 101 103 103 3.9 99 101 100 102 100 100 20.3 101 103 104 99 95 105 101 102 Cluster weight (g/cluster) Mean value (n=5-8*) TSS (°Brix) Mean value (n=5-22*) Acidity (g tartaric acid/L) Mean value (n=5-13*) Berry Firmness (N) Mean value (n=5-13*) Return bloom / yield in the year following the application (# fully developed clusters/vine) Mean value (n=5-6) 40.5 102 102 100 99 Cluster weight determined at-harvest, means for the other parameters include pre-harvest determinations. * POSTER PRESENTATIONS 156 7th International Table Grape Symposium Table 5: Effects on quality parameters (apart from colour) and return bloom in the T studies*. Efficacy (treatment values as % UTC, where UTC = 100%) Parameter UTC (absolute values) Ethephon 60g a.s.hL-1 753 ProTone (40g a.s.hL-1) A B AB BC ABC BCD 102 101 102 102 107 106 110 17.7 101 99 99 98 99 97 102 4.3 94 98 99 97 101 94 94 19.9 98 99 98 97 99 101 96 95 103 Cluster weight (g/cluster) Mean value (n=4-8**) TSS (°Brix) Mean value (n=15-26**) Acidity (g tartaric acid/L) Mean value (n=11-15) Berry Firmness (N) Mean value (n=11-15) Return bloom / yield in the year following the application (# fully developed clusters/vine) Mean value (n=4-6) 41.2 93 96 96 94 98 Application timings: A: When 5% or less berries began softening; B: At véraison: when 20-30% of berries began to develop colour; C: 2 weeks after application B; D: 2 weeks after application C. ** Cluster weight determined at-harvest, means for the other parameters include pre-harvest determinations. * Our findings are in strong agreement with earlier studies that s-ABA can be an effective additional tool to improve colour development in red table grapes. The commercial development of ProTone (SL, 10% s-ABA) will provide table grape growers in the EU with an effective and safe user and consumer friendly alternative to ethephon. Acknowledgements This work was financially supported by VBC and undertaken using independent GEP (Good Experimental Practice) certificated field research co-operators in Greece, Italy and Spain. References Ban T, Shiozaki S, Ogata T, Horiuchi S. 2000. Effects of abscisic acid and shading treatments on the levels of anthocyanin and resveratrol in skin of ‘Kyoho’ grape berry. Acta Horticulturae 514:83-89. Cantin CM, Fidelibus MW and Crisosto CH. 2007. Application of abscisic acid (ABA) at véraison advanced red colour development and maintained postharvest quality of ‘Crimson Seedless’ grapes. Postharvest biology and technology 46:327-241. Cutler AJ and Krochko JE. 1999. Formation and breakdown of ABA. Trends in Plant Science 4:472-478. Fukushima M, Iwasaki N, Gemma H and Oogaki,C. 1990. Effect of night cooling at high temperature season on vine growth and berry ripening of grape ‘Kyoho’ (Vitis Vinifera x V. Labrusca L.). Acta Horticulturae 279:321-326. Gu S, Jacobs S. Du G. 2011. Efficacy, rate and timing of applications of abscisic acid to enhance fruit anthocyanin contents in ‘Cabernet Sauvignon’ grapes. Journal of Horticultural Science and Biotechnology 86:505-510. Peppi MC and Fidelibus MW. 2008. Application, timing and concentration of abscisic acid or ethephon and their effects on colour of ‘Crimson Seedless’ table grapes. Acta Horticulturae 774:173-178. 157 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 18 Inheritence of terpenoids in F1 population of ‘Jingxiu’ and ‘Xiangfei’ grape L Sun1, BQ Zhu2, XR Sun1, GJ Zhang1, AL Yan1 and HY Xu1* Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, A-12, Ruiwangfen, Xiangshan, Beijing, 100093, P.R. China 2 Beijing Forestry University, 35#, East Qinghua Road, 100083, P.R. China * Corresponding Author: Tel: 8610-82592156, Email:[email protected] 1 Background and Aims Flavour and aroma are one of the most important characters for the selection of new table grape cultivars. It is generally acknowledged that terpenes are responsible for the Muscat flavour (Mateo and Jimenez, 2000). Understanding the inheritance of terpenes is very important in our breeding program which aims to develop new varieties. In our previous studies, a range of volatile compounds have been identified, including esters, alcohols, carbonyl,C6 and terpenes, but only 5-10 terpenes have been identified for the inheritance research in grape as linalool, geraniol, α-terpineol showed continuous variation and did not segregate in the F1 population. In contrast (Z)-linalool oxide, nerol oxide, nerol, neral, geranial and geranic acid segregated in different ratios and exhibited as qualitative character (Wu et al., 2013). In this work, we will identify more terpenes by means of GC-MS-AMDIS method and study the heredity of these terpenes to enhance the understanding of genetic mechanisms and improve breeding efficiencies. Experimental Procedure and Results All ripen berries from the plants of ‘Jingxiu’, ‘Xiangfei’ and 47 F1 progenies were collected in 2010 and quickly frozen by liquid nitrogen and stored at -80℃. Peduncles and seeds were removed from the berries and a 50g sample was crushed by blender. After maceration for 40 min, the flesh was centrifuged at 8000rpm at 4℃ for 10 min. Then 5ml of supernatant, 1g NaCl and 30ul of 4-Methyl-2-pentanol (2g.L-1) were put into a 15ml vial for application of headspace solid-phrase micro-extraction methods. An agilent 7890GC and 5975MS were employed to separate and identify the aromatic volatiles using a 60m ×0.25mm HP-INNOWAX capillary column with 0.25um film thickness. The carrier gas was helium at a flow rate of 1 ml/min. Samples were injected by placing the SPME fibre at the GC inlet for 25 min in the splitless mode. The oven’s starting temperature was 50°C, which was held for 1 min, then raised to 220°C at a rate of 3°C. min-1 and held at 220°C or 5 min. The mass spectrometer in the electron impact mode (MS/EI) at 70eV was scanned in the range of m/z 20–450. The mass spectrometer was operated in the full scan mode with the selective ion mode (SIM) under auto-tune conditions at the same time. Terpenoids were identified by standard NIST 05 library and retention index reported in the literature. Quantification was carried out by using internal standards. For the compounds that showed continuous variation, the CV was calculated by (Standard Deviation/ mean progeny value) x 100% while for the compounds that segregated in the progenies, the ratio of presence or absence in the progenies was calculated. The X2 test was performed by SPSS and a histogram map developed using R software. A total of 56 terpenes, including some in trace amounts, were detected of which 44 can be identified. Thirteen terpenes showed continuous variation (Table 1), including cis-rose-oxide, trans-rose-oxide, linalool, menthol, ethanol-3, 3-dimethylcyclohexylidene, p-myene, geranial, γ-geraniol, nerol, ß-damascenone, geraniol, geranylacetone and ß -ionone, among which linalool, nerol, geranial, geraniol and γ-geraniol were the predominant terpenes and accounted for 81.46% of the total terpenes. The content of linalool varied significantly among the progenies, ranging from 6.35-1221.65 ug.kg-1 with distribution towards low values. The mean value of geraniol, geranyl-acetone, and ß-ionone were higher than the mid-parent value, indicating transgressive inheritance. The coefficient of variance of γ-geraniol and p-myene were 1.79% and 1.96% respectively, suggesting stable inheriting capability for these two compounds, while for linalool, geraniol and ethanol-3,3-dimethylcyclohexylidene, they were 144.41%, 168.08% and 113.10%, indicating good potential for selecting high contents of these compounds. POSTER PRESENTATIONS 158 7th International Table Grape Symposium Table 1. Analysis of the 13 terpenes which showed quantitative inheritance. Terpenoid Jingxiu Xiangfei MPV M Range CV (ug.kg-1) (ug.kg-1) (ug.kg-1) (ug.kg-1) cis-rose oxide 1.70 2.53 2.12 1.62 0.0001-3.00 47.97 trans-rose oxide 1.70 1.94 1.82 1.40 0.0001-1.96 52.13 linalool 6.50 3034.69 1520.60 228.98 6.35-1221.65 144.41 menthol 0.28 0.58 0.43 0.31 0.20-0.54 21.44 Ethanol 2-3 3-dimethyl hylcyclohexylidene-Z- 0.26 54.32 27.29 4.13 0.24-32.17 168.08 P-cymene 16.92 19.02 17.97 17.12 12.74-18.56 1.96 geranial 10.65 18.28 14.46 13.70 10.00-25.51 34.19 γ-geraniol 55.06 55.71 55.38 55.69 54.97-60.13 1.79 nerol 35.21 62.60 48.90 49.05 35.13-129.38 40.36 β-damascenone 4.90 9.51 7.21 6.73 2.85-10.67 28.01 geraniol 59.80 168.24 114.02 159.36 55.78-994.78 113.10 Geranylacetone & piperonyl_acetone 1.61 1.78 1.69 1.76 1.18-3.28 29.48 β-ionone 5.36 7.72 6.54 6.49 5.27-28.33 8.3 MPV: mid- parent value, M: mean progeny value, CV: coefficient of variance Another 27 terpenes including α-terpinene, ß-citronellol, ß-myrcene, ß-phellandrene, limonene, (E)-β-ocimene, (Z)-β-ocimene, alloocimene, (E,Z)alloocimene, 2,6-Dimethyl-1,3,5,7-octatetraene, cis-furan linalool oxide, trans-furan linalool oxide, 6-methyl-5-hepten-2-ol, nerol oxide, camphor, α-terpinenol, hotrienol, carvomenthenal, neral, lilac alcohol, trans-pyran linalool oxide, cis-pyran linalool oxide, geranyl acetate, 2,6-Dimethyl-3,7-octadiene-2,6-diol, Z-nerolidol, E-nerolidol, 2,6-Dimethyl-1,7-octadiene-3,6-diol segregated into presence or absence in the progenies. Through χ2 test, some compounds showed 1:1, 1:3, 1:15 ratio, which indicating they were qualitative traits, controlled by one or several genes (Table 2). Discussion and Significance of the Study No terpenes were detected in the maternal parent cultivar Jingxiu, while only 17 terpenes were detected in the paternal parent Xiangfei in a previous study (Yang, 2009). However, using automatic mass spectral deconvolution and identification system (AMDIS), we identified 40 terpenes in Jingxiu and 44 terpenes in Xiangfei. There have been research in which Muscat flavour was reported to be controlled by five dominant genes and a modifier gene (Wanger, 1967). Several QTL studies involving terpenes have also been conducted (Doligez, 2006). In this research, inheritance pattern of terpene was investigated. The results indicate that several important terpenes contributing to Muscat flavour seem to be controlled by polygenes as terpene contents showed wide range of variance in the progeny plants. Some progenies with higher terpene levels than Xiangfei were found in the population, indicating promising potential in breeding for aroma and flavour in table grapes. 159 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 2 Analysis of the 13 terpenes which showed qualitative inheritance. Terpenoid Jingxiu (ug.kg-1) Xiangfei (ug.kg-1) M (ug.kg-1) P A χ2 test hotrienol 6.10 85.54 12.64 45 2 15:1 carvomenthenal 9.90 10.50 7.55 36 11 3:1 neral 9.99 11.05 8.72 39 8 3:1 Lilac alcohol C 6.10 6.75 3.04 7 40 1:3 cis-pyran linalool oxide 6.10 32.07 6.56 33 14 3:1 β-citronellol 1.63 7.46 3.02 43 14 3:1 Geranyl acetate 3.40 3.40 1.83 9 38 1:3 3 7-Octadiene-2 6-diol 2 6-dimethyl- 6.90 14.89 5.61 31 16 3:1 Z-nerolidol 6.70 6.70 3.12 2 45 1:15 E-nerolidol 6.90 6.90 3.72 4 43 1:15 1 7-Octadiene-3 6-diol 2 6-dimethyl- 6.90 9.70 4.64 18 29 1:1 terpinolene 2.40 12.90 3.31 44 3 15:1 β-myrcene 0.72 65.66 11.56 44 3 15:1 α-terpinene 2.40 4.43 2.35 29 18 3:1 β-Phellandrene 2.40 8.85 2.67 36 11 3:1 limonene 8.50 40.87 10.34 34 13 3:1 E-β-ocimene Z 0.60 11.99 2.70 38 9 3:1 E-β-ocimene E 0.60 22.33 5.27 39 8 3:1 p-cymene 16.92 19.02 16.86 7 40 1:3 alloocimene 0.60 8.39 1.90 45 2 15:1 E_Z-alloocimene 0.60 3.89 1.02 45 2 15:1 2 6-Dimethyl-1 3 5 7-octatetraene E E- 0.60 1.19 0.57 26 21 1:1 cis-furan linalool oxide 0.00 159.74 12.78 41 6 15:1 5-hepten-2-ol 6-methyl- 54.90 56.768 53.51 44 3 15:1 trans-furan linalool oxide 0.00 129.835 3.62 37 10 3:1 Nerol oxide 9.90 10.277 7.71 32 15 3:1 camphor 9.90 10.26 9.24 25 22 1:1 4-terpinenol 0.20 0.66 0.21 36 11 3:1 M: mean progeny value, P: presence, A: absence POSTER PRESENTATIONS 160 7th International Table Grape Symposium Acknowledgements This work was supported by China Agriculture Research System (CARS-30-yz-3), we thank the technical assistance of X.Q. Xu and D.Wang. References Doligez A, Audiot E, Baumes R, This P. 2006. QTLs for muscat flavour and monoterpenic odorant content in grapevine (Vitis vinifera L.). Molecular Breeding 18:109-125. Mateo JJ and Jime´nez M. 2000.Monoterpenes in grape juice and wines. Journal of Chromatography A 881:557-567. Wagner R,1967. Etude de quelques disjonctions dans des descendances de Chasselas, Muscat Ottonel et Muscat a` petits grains. Vitis 6:353-363. Wu BH, Yang CX, Liang ZC, Liu W, Wang YY, Liu CY and Li SH. 2013. Inheritance of berry volatile compounds in two half-sib grape (Vitis vinifera) populations. Euphytica 189: 351-364. Yang CX, Wang YJ, Liang ZC, Fan PG, Wu BH, Yang.L, Wang YN, Li SH. 2009. Volatiles of grape berries evaluated at the germplasm level by headspace-SPME with GC–MS. Food Chemistry 114:1106-1114. 161 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 19 Making decisions in table grape production with benchmarking data Garth Swinburn Sun World Australasia Pty Ltd, PO Box 1446 Mildura, VIC 3502, Email: [email protected] Background and Aims Most successful primary industries use data to help them manage production systems and steer their way in the global markets. Indices, growth trends, market feedback and benchmarks allow industries to identify where improvements can be made to strengthen their collective competitive advantage. Table grape industries in each region around the world need to know where they sit against their competitors, not only in the cost of production arena, but increasingly and more importantly in other aspects in the supply chain. For example, quality attributes of grapes drive sales and build markets; food safety issues in some market sectors can provide opportunities for product differentiation; and supply chain reliability is becoming more important in many markets as global supply becomes increasingly seamless. Although the data and market intelligence gathered is not strictly scientific in nature, the process of comparing and benchmarking production regions is very much about objective analysis, ratios and analysing trends to determine where an industry should be allocating its resources to build national competitiveness. On a more ‘grass-roots’ production level, such signals also provide valuable information for individual grape businesses to identify drivers of productivity and profitability. Table grape businesses need to know about profit margins, returns, cost of production and where their proprietary resources should be allocated to ensure productivity is maximised, year-in, year-out. With the increasing number of new varieties becoming available to table grape growers, there are many questions that must be answered before old varieties are removed and before investment is made in new infrastructure and plant material. The answers can be largely addressed with simple benchmarks that provide guidance to growers on cropping performance and market returns. Decisions made with information in isolation can be misleading to growers wanting to move to new varieties. For example, if market returns appear to be low for a new variety (compared to an established public variety), then clearly changes are unlikely to occur. However if a grower is provided with seasonal weighted average returns for a particular variety and this is benchmarked not only with other growers producing the same variety but benchmarked with other varieties in the same time slot, then a fair comparison can be made. Sun World is developing the concept of benchmarking with its licensed growers by providing simple summaries of weighted average data so they can make their own comparisons with other existing or new varieties. If this is done over a number of seasons, then a grower’s decision to remove a variety and replace with a higher performing variety is based on objective information. The premise of this work is that growers find it difficult to improve productivity in isolation; they need to be placed in context of other growers in a similar region and other varieties in the same harvest time. Experimental Procedures and Results Seasonal data for crop yields and market returns are collected for a group of growers. Planted areas (hectares) vine age and growing region are known. Data is collated and simple benchmarks are calculated. Some examples of benchmarks are: • • • Yield per hectare or per vine – this highlights the variety’s fertility and productivity in the vineyard but does not take into account the cost and effort in getting the fruit into a packed box for market. Gross return per hectare – this combines yield and average price per kilo and indicates a relative return per unit of land farmed. Net return per hectare can be calculated by using an estimated cost per hectare or vine for a specific variety. Growers can of course use their own actual costs. Highly productive varieties can sometimes be costly to grow, thus negating the yield benefits. POSTER PRESENTATIONS The seasonal data are collected and collated in to simple benchmarks, which are then presented to growers in graphical form. Each grower is allocated a grower code to provide anonymity and retain confidentiality within the grower group (Figure 1). 162 7th International Table Grape Symposium 4.5 160 2013-14 Season 140 4.0 3.5 120 3.0 100 $/vine RETURNS $/ vine 80 2.5 YIELD ctn/ vine 2.0 10kg ctn/vine 60 1.5 40 1.0 20 0.5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Grower Code Figure 1: Returns and Yield for Midnight Beauty®. Note: the light bars indicate early season cropping areas, such as Queensland. Some of the very low yields could be attributed to young vines or adverse weather damaging the crop. There are also other less objective benchmarks or evaluation indices that can be used to add to the decision making process, if a grower is considering removing an existing variety and planting a new variety. A simple evaluation sheet can be set up to score alternative varieties. Table 1. Comparison of two possible grape varieties. Variety A Production Indices Variety B Score 1-9 Weight Final Score Score 1-9 Weight Final Score Crop Yield 6 50% 3 8 50% 4 Tree & Fruit Health 6 20% 1.2 7 20% 1.4 Cost of Production 7 20% 1.4 8 20% 1.6 Fits with existing varieties 9 10% 0.9 4 10% 0.4 100% 6.5 100% 7.4 Score 1-9 Weight Final Score Score 1-9 Weight Final Score Returns $/kg 8 40% 3.2 8 40% 3.2 Shelf Life 6 10% 0.6 8 10% 0.8 Appearance or Eye Appeal 7 10% 0.7 7 10% 0.7 Eating Experience 7 10% 0.7 7 10% 0.7 Product Placement 6 20% 1.2 7 20% 1.4 Crop Volume 3 10% 0.3 7 10% 0.7 100% 6.7 100% 7.5 out of 18 13.2 out of 18 14.9 Market Indices 7th International Table Grape Symposium 163 POSTER PRESENTATIONS Each index is rated on a 1-9 score where 1 is unfavourable and 9 is very favourable. Each index has a weighting to reflect the importance to the success of the new variety within the individual business - this percentage can be determined by the grower. When the two figures are multiplied together and added up, a total score provides a weighted indicator of the best likely variety for a particular situation. In Table 1, Variety B has achieved a higher total score (14.9) than Variety A (13.2) based on weighted indices. Discussion and Significance of the Study Table grape growers need to have access to decision making tools to assist them in determining how a variety is performing year-in, year-out and this can be provided in the form of basic benchmarking. They also need a mechanism to help them decide on whether to replace an existing variety with a new variety and this can be achieved with simple evaluation models. Figure 1 provides growers of Midnight Beauty® grapes information that indicates their placement and helps them analyse their performance in the context of 44 other growers, from both early and main season regions. This provides a simple but valuable tool in deciding: • How to increase the performance of their Midnight Beauty® through better irrigation, nutrition and bunch management. • Whether to keep the variety and increase plantings or, • Whether to remove the variety and find something more productive and profitable. It would be prudent to undertake this analysis over a number of seasons before any major decisions were taken to plant or replace a variety. Seasonal variances in production and pricing can change the picture markedly and indeed the fact that there are large variations in the annual performance of a specific variety should certainly count against it. Table 1 is an example of how a grower who is looking to remove Variety A and replace it with Variety B can proceed with a degree of confidence that the decision was based on weighted indices rather than pieces of isolated, disconnected information. There is no doubt that yields are the main driver of profitability in most horticultural crops. However, other aspects of table grape varieties are important to consider, for example how much wastage does the supermarket endure (shelf life); what are the supply conditions (volumes) for a variety; does the variety require high input costs to get it into the box? The importance of these other factors can be assessed, weighted and used in a simple evaluation table in determining the potential of a new variety. With the evolution of new varieties from a range of grape breeding programmes, there are elements of confusion and misperception about the value of these varieties. Net returns per hectare, over a number of seasons for a specific variety, is an excellent indicator of value to a grower because it encompasses, yields, returns and costs. Objective benchmarks therefore allow growers to make informed decisions about removing and replacing existing varieties. Other factors relating to market attractiveness of the variety can also be assessed and used in this decision making with simple evaluation tools. Acknowledgement Sun World acknowledges the licensed growers in embracing this concept and supporting the development of a more comprehensive mechanism to assist them in decision making. We thank the licensed marketers for their role in supporting this feedback to growers to help them lift productivity. POSTER PRESENTATIONS 164 7th International Table Grape Symposium ID 20 Prospecting for fungicide activity on wild mushrooms extracts against gray and blue mould of table grapes P Ugalde and JL Henríquez* Fac. Cs. Agronómicas, Universidad de Chile, Santa Rosa 11.315, Casilla 1004, La Pintana, Santiago Chile *Corresponding author: Email: [email protected] Background and Aims Postharvest rots of table grapes are a constant problem for the industry with Botrytis cinerea Pers. ex F. and Penicillium expansum Link. as the most important pathogens causing grey and blue mould, respectively. Restrictions on the maximum amount of pesticide residues allowed on the fruit, and the limited number of fungicides registered in the markets have prompted the look for alternatives to traditional chemical fungicides, focusing mainly on natural products, which are environmentally friendly and free from residue restrictions. Most research has been focused on the use of plant extracts and biocontrol agents, and actually some commercial fungicides obtained from plant extracts (citric extract, tea tree oil), or biocontrol agents (Bacillus subtilis (Ehrenberg) Cohn) are being used for the control of pre-harvest table and wine grape rots. Mushroom extracts have been mainly screened for activity against human pathogens, with few studies on plant pathogens. Nevertheless, the strobilurin fungicides were originally obtained from a wild mushroom. This study aimed to evaluate the activity of 15 extracts of wild mushrooms in the control of both grape pathogens. Experimental Procedure and Results The mushrooms were collected from their natural sources, oven dried, grounded and macerated in ethanol 95 % v/v within 48 hours, following the procedure reported by Stadnik et al., (2003). The extracts were tested in a dilute solution of ethanol 10 % v/v, and evaluated in vitro and in vivo. Potato dextrose agar media was amended with the ethanol extracts at a rate of 1%, for the in vitro tests, where the inhibition of the growth of the mycelia or the germination of the conidia of the pathogens was measured. The extracts of the five mushrooms that showed the greatest in vitro activity were in vivo assayed on Red Globe berries that were surface disinfected with NaOCl (0.5 %) or not disinfected at all. The berries were wound inoculated with a spore suspension (1x105 conidia.mL-1) of each pathogen 1 or 24 hours after the extracts treatments, incubated at 20°C for 5 days and assessed for disease. All the mushroom extracts tested inhibited the growth of the mycelium and the germination of conidia of B. cinerea (Table 1). The effect on the mycelium of B. cinerea was greater than the effect on the conidia of this pathogen, with four extracts inhibiting more than 60% of the mycelium growth, reaching up to a 92.8 % for the extract of Suillus luteus (Table 1). The unidentified species of Agaricacea (Agarical sp.) showed a high activity both on the mycelium and the conidia of B. cinerea. Eleven mushroom extracts showed some inhibitory response on the growth of the mycelium of P. expansum, but unlike the activity against B. cinerea, the levels of inhibition were lower reaching up to a 35.3 % for the extract of Agarical sp. (Table 2). Higher levels of inhibition were observed for the germination of the conidia of P. expansum, compared both with the inhibition of the mycelium of this pathogen and compared with the inhibition of the germination of conidia of B. cinerea. The extracts of Agarical sp., Suillus luteus and Agaricus arvensis gave the highest levels of inhibition on the development of both pathogens. Only the extract of Amanita sp. inhibited the development of grey and blue mould on Red Globe grapes, when it was applied 24 hours before the inoculation with the pathogens. None of the other extracts affected the in vivo development of the pathogens (data not shown). 165 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 1. Inhibition (%) of the mycelial growth and germination of conidia of Botrytis cinerea by the ethanolic extracts of wild mushrooms. Mushroom species Inhibition (%) Mycelial growth Germination of conidia Suillus luteus 92.8 aX 5.4 cX Agarical sp. 71.0 a b 54.6 a Amanita sp. 69.4 a b -Y Agaricus arvensis 63.7 b 7.0 c Calvatia cyathiformis 46.2 b 17.0 b Tricholoma scalpturatum 29.4 c 9.4 b c Suillus granulatus 29.0 c - Bjerkandera adusta 23.4 c d 10.0 b Tricholomatacea sp. 19.4 d 7.8 b c Laetiporus sulphureus 18.6 d 6.2 c Agaricus xanthodermus 17.8 d 5.6 c Macrolepiota rhacodes 16.6 d e 28.8 a Agaricus sp. 12.1 d e 6.4 c Paxillus panuoides 10.6 e 13.0 b Russula nothofaginea 5.6 e - Means followed by the same letter in each column are not different according to Fisher´s LSD (p≤0.05). Not tested for the inhibition of the germination of conidia. X Y Table 2. Inhibition (%) of the mycelial growth and germination of conidia of Penicillium expansum by the ethanolic extracts of wild mushrooms. Mushroom species Inhibition (%) Mycelial growth Germination of conidia Agarical sp. 35.3 aX 4.4 d Agaricus arvensis 34.5 a 87.0 a Suillus luteus 29.9 b 46.6 b c Calvatia cyathiformis 28.3 b c 5.6 d Laetiporus sulphureus 26.1 c 71.0 a b 25.7 c d 3.0 e 23.3 d 25.2 c Macrolepiota rhacodes 18.9 e 2.8 e Tricholoma scalpturatum 17.7 e f 0.8 f Agaricus sp. 13.0 f 57.6 b Bjerkandera adusta 12.9 f 4.4 d Paxillus panuoides 4.9 g 3.2 e Suillus granulatus 0.0 h -Y Amanita sp. 0.0 h - Russula nothofaginea 0.0 h - Tricholomatacea sp. Agaricus xanthodermus Means followed by the same letter in each column are not different according to Fisher´s LSD (p≤0.05). Not tested for the inhibition of the germination of conidia. X Y POSTER PRESENTATIONS 166 7th International Table Grape Symposium Discussion and Significance of the Study The results obtained showed that most of the mushroom studied had some inhibitory effect on the development of the grape pathogens studied, confirming results obtained in similar studies (Domínguez, 2013; Ngai, 2003; Türkoğlu et al., 2011). The effects are dependent on the pathogen and indicate that there is a variety of compounds that are acting with high levels of specificity on the different pathogens. There is a high potential for the development of both natural fungicides as well as the discovery of new molecules that could be synthesized and used in the development of new synthetic fungicides. References Domínguez V. 2013. Evaluación de extractos de macrohongos con acción inhibitoria de patógenos de importancia agrícola. Santiago. Chile. Tesis Magister en Ciencias Agronómicas e Ingeniero Agrónomo mención Sanidad Vegetal, Universidad de Chile. 46p. Ngai P. 2003. Lentin, a novel and potent antifungal protein from shitake mushroom with inhibitory effects on activity of human immunodeficiency virus-1 reverse transcriptase and proliferation of leukemia cells. Life Sciences 73: 33633374. Stadnik M, Bettiol W, Saito M. 2003. Bioprospecting for plant and fungus extracts with systemic effect to control the cucumber powdery mildew. Journal of Plant Disease and Protection 110(4): 383-393. Türkoglu A, Guler P, Araz A, Kutluery F, Kunduz I. 2011. Antifungical effects of Clitocybe odora (Bull. Fr) Kum. against the plant pathogens, Fusarium culmorum and Fusarium moniliforme. Hacettepe The Journal of Biological Chemistry 39(1): 5-60. 167 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 21 The effects of elevated CO2 and a rise in air temperature on commercially grown grapevines Dale J. Unwin1, Everard J. Edwards3, Karl J. Sommer1, Mahabubur Mollah2 and Rachel L. Kilmister1* Department of Environment and Primary Industries, Mildura, Australia Department of Environment and Primary Industries, Horsham, Australia 3 CSIRO Plant Industry, Adelaide, Australia * Corresponding author: Email: [email protected] 1 2 Background and Aims The report by the Intergovernmental Panel on Climate Change (IPCC) in 2007 states that the largest driver of temperature elevation is atmospheric carbon dioxide (CO2) concentration (Carter et al., 2007). CO2 in the atmosphere is currently 401ppm and it is predicted that it will reach 550 ppm by 2050. The IPCC predicts global average temperature to rise to between 1.1°C and 6.4°C by the end of the century (Solomon et al., 2007). Data collected over multiple vintages indicate warming of viticultural regions is occurring in both the Northern and Southern Hemispheres (Jones et al., 2005, Webb et al., 2011). In Australia this has had an effect on the phenology of grapevines (Vitis vinifera L.) with harvest dates advancing by approximately eight days per decade over the last 30 years in Australia (Webb et al., 2011). Consequently, vineyard management techniques with regard to yield, water use efficiency, phenology, and pest and disease incidence are likely to be impacted by a future climate. Field based studies of the effects of elevated CO2 on grapevines have been conducted in the past (Bindi et al., 2001, Mountinho-Pereira 2009, Goncalves et al., 2009) but have been limited in scope and have not previously been combined with the control of air temperature. Recent studies have examined the effects of elevated temperature on mature grapevine performance using open top chambers with active heating facilities (Sommer et al., 2012). The aim of this study was to investigate the combined impacts of elevated CO2 and temperature on grapevine phenology, vine growth, carbohydrate status, canopy physiology, nutrition and productivity. Preliminary results of leaf conductance, photosynthesis, sap flow and carbohydrate reserves will be reported in the poster. Experimental Procedure and Results A field experiment was established using open top chambers in a Shiraz (Vitis vinifera L.) vineyard in the Sunraysia region of Victoria in July 2013. The experiment consisted of five treatments: elevated CO2 > 550ppm at ambient temperature (eCO2); ambient CO2 at elevated temperature > ambient + 2°C (eT); combined elevated CO2 > 550ppm and elevated temperature > ambient + 2°C (eCO2eT); ambient CO2 at ambient temperature in an open top chamber (OTC); and an ambient CO2 at ambient temperature with no chamber (Control) replicated four times in a randomised complete block design. Each open top chamber was 2.4m high and enclosed three mature commercially grown Shiraz vines and a ducted air-unit which directed high-volume low-velocity air below the grapevines. The elevated temperature treatments incorporated a series of finned heating elements added to the air-unit, heating the air before it was expelled through 100 mm ducts facing the ground. The elevated CO2 was introduced into the open top chambers using two horizontal fumigation tubes spaced at 800mm within the canopy at a height of 1.3m. A CO2 sensor at 1.7m controlled the amount of CO2 gas within the open top chambers. Results from year 1 of this study found that an approximate 2°C increase in temperature accelerated cap fall by 5 – 9 days and véraison by 7 – 12 days. However, while the phenology shifted due to eT, there was no change in leaf conductance (Figure 1). These results confirm previous work on the effects of eT on a white grape variety and two red grape varieties (Sommer et. al. 2012). The addition of elevated CO2 at ambient temperature reduced leaf conductance (Figure 1), which may lead to improved water use efficiency (Ziska and Bunce 2006). The effect of elevated CO2 and elevated temperature on leaf conductance was inconsistent (Figure 1). POSTER PRESENTATIONS 168 7th International Table Grape Symposium Figure 1. The effects of elevated CO2 (eCO2), elevated air temperature (eT) and the combination of elevated CO2 and air temperature (eTeCO2) on leaf conductance of Shiraz vines at pre-véraison (16/12/2013) and veraison (2/01/2014). Error bars represent the standard error. Discussion and Significance of the Study The results shown here suggest that although elevated CO2 decreased leaf conductance there is the potential for an increase in carbohydrate reserves. However, the results are only preliminary and it is uncertain how higher CO2 levels will affect grapevine productivity and grape and wine quality. Without such knowledge it is difficult for the industry to put in place adaptive strategies to enhance positive or overcome potentially negative impacts. This study will continue and identify any changes in vegetative growth, photosynthesis, carbohydrate storage, yield, grape and wine quality over multiple seasons. Acknowledgements Department of Environment and Primary Industries, CSIRO and the Australian Grape and Wine Authority (previously Grape and Wine Research and Development Corporation). References Bindi M, Fibbi L, Miglietta F. 2001. Free air CO2 enrichment (FACE) of grapevine (Vitis vinifera L.): II.Growth and quality of grape and wine in response to elevated CO2 concentrations. European Journal of Agronomy 14: 145-155. Carter TR, Jones RN, Lu X, Bhadwal S, Conde C, Mearns LO, O’Neill BC, Rounsevell MDA, Zurek MB. 2007. ML Parry, OF Canziani, JP Palutikof, PJ van der Linden, CE Hanson eds. New assessment methods and the characterisation of future conditions. Climate Change 2007: Impacts, adaptation and vulnerability’. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. (Cambridge University Press: Cambridge, UK) pp.133 -171. Gonçalves B, Falco F, Moutinho-Pereira H, Bacelar E, Peixoto F, Correia C. 2009. Effects of elevated CO2 on grapevine (Vitis vinifera L.): volatile composition, phenolic content, and in vitro antioxidant activity of red wine. Journal of Agricultural and Food Chemistry 57: 265-273. Jones GV, White, MA, Cooper RO, Storchmann K. 2005. Climate Change and Global Wine Quality, Climate Change 73 319-343. Moutinho-Pereira J, Gonçalves B, Bacelar E, Cunha JB, Coutinho J, Correia CM. 2009. Effects of elevated CO2 on grapevine (Vitis vinifera L.): Physiological and yield attributes. Vitis 48, pp. 159–165. Sommer KJ, Edwards EJ, Unwin DJ, Mazza M and Downey MO. 2012. Strategies to maintain productivity and quality 7th International Table Grape Symposium 169 POSTER PRESENTATIONS Solomon S, Qin D, Manning M, Alley RB, Berntsen T, Bindoff NL, Chen Z, Chidthaisong A, Gregory JM, Hegerl GC, Heimann M, Hewitson B, Hoskins BJ, Joos F, Jouzel J, Kattsov V, Lohmann U, Matsuno T, Molina M, Nicholls N, Overpeck J, Raga G, Ramaswamy V, Ren J, Rusticucci M, Somerville R, Stocker TF, Whetton P, Wood RA, Wratt D. 2007. S Solomon D Qin, M Manning, Z Chen, M Marquis, KB Averyt, M Tignor and HL Miller eds. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Technical Summary. in a changing environment-Impacts of global warming on grape and wine production. Final Report, Department of Primary Industries, Irymple, Victoria, http://research.agwa.net.au/completed_projects/strategies-to-manage-theimpacts-of-global-warming-on-winegrape-production/ Ziska LH, and Bunce AB. 2006. JIL Morison and MD Morecroft eds. Plant responses to rising atmospheric carbon dioxide. Plant Growth and Climate Change (Blackwell Publishing.Ltd: Oxford, UK) pp. 24. POSTER PRESENTATIONS 170 7th International Table Grape Symposium ID 22 Effect of NAA on the sucrose metabolism and expression of some related genes in grape fruit Xicheng Wang*, Weimin Wu, Minzhen Zhao, Yaming Qian and Zhuangwei Wang Institute of Horticulture, Jiangsu Academy of Agricultural Sciences, 50 Zhongling street, Nanjing, 210014, P. R. China Background and Aims The effects of the plant growth regulator Naphthaleneacetic acid (NAA) on total soluble sugars and spatiotemporal expression of related genes in the grape variety ‘Qinlongdasui’ were investigated in this study. Experimental Procedure and Results Naphthaleneacetic acid (NAA) solutions of 0, 50, 100 and 200mg/L were applied ton ‘Qinlongdasui’ grape fruit at véraison, when berry colour was changing. The result showed that glucose and fructose were the main components of the soluble sugar in ‘Qinlongdasui’ grape. Content of glucose and fructose increased from véraison until harvest. Accumulation of the soluble solids and total sugar was inhibited, and the maturity period delayed by the use of NAA although the treatment had little effect on berry weight. It was found that the expression of neutral invertase gene (NI), sucrose synthase gene (SS) and sucrose phosphate synthase gene (SPS) was inhibited by NAA to varying extents. The inhibitory effect of NAA on the related gene expression of sucrose metabolism was more noticeable with increasing NAA concentration, but it has little effect on the expression of fructokinase gene (FRK). Discussion and Significance of the Study The results of the study indicate that NAA might be involved in the regulation of ripening and sucrose metabolism in grape, and inhibited the synthesis and accumulation of sugar. NAA shows promise as a tool for growers to delay ripening and extend the harvest season. 171 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 23 Effects of natural auxin-based Ecklonia maxima seaweed product on reduction of postharvest berry drop in table grape cv. Thompson Seedless Victor Giancaspero1 and Pedro Larrain2* Prokambium Consultancies & Research, Av. Manuel Montt 1680, Providencia, Santiago, Chile Kelp Products International (Pty) Ltd – Latin America. Av. El Golf de Manquehue 9755-13 Lo Barnechea, Santiago, Chile * Corresponding author: Tel: 56 993252638, Email: [email protected] 1 2 Background and Aims Postharvest berry drop is a serious problem in many table grapes. Thompson Seedless is one of the most sensitive, causing marketing problems that can significantly reduce grower income. One known reason for berry drop is GA3 treatments applied to achieve the required berry weight (Retamales, et al., 1995). Application of CPPU, mainly in a mix with GA3 for berry size-weight reported an increase of berry drop, possibly due to a reduction of the pedicel flexibility (Navarro et al., 2001). Many products are tested to reduce postharvest berry drop without consistent results or negative collateral effects. Application of the synthetic auxin 4-CPA significantly reduced berry drop but delayed ripening (Ben-Tal, 1990). Treatment with the seaweed product Kelpak®, could possibly help reduce berry drop, as it is seen as an auxin-dominant product (Crouch and Van Staden, 1991). The objective on this study was to validate the berry drop reduction reported in previous reports on Kelpak® applied for berry sizing. These reports indicated that significant reduction of postharvest berry drop can achieved with a very early spray of Kelpak® at 2-3mm berry size stage. Experimental procedures Trials over seasons 2010-11 and 2011-12 were conducted in Viluco, Metropolitan Region, Chile on table grape cv. Thompson Seedless with Kelpak® a natural auxin-based seaweed product extracted from the seaweed species Ecklonia maxima. Season 2010-11: Control (T0) was the standard farming practice with four GA3 applications, 20ppm @ 2-3mm berry size, 30ppm @ 4, 6 and 8mm, plus a CPPU spray at 2g.ha-1 applied together with GA3 at 6mm berry size. The Ascophyllum nodosum seaweed product Goëmar Calibra® at 3L.ha-1 was also applied at 6mm separate from the tank mix of GA3 and CPPU. Kelpak treatment 1 (T1) was 3 sprays of 7L.ha-1 at 4, 6 and 8mm and treatment 2 (T2) was 4 sprays of 4.5L.ha-1 at 2-3mm, 4, 6 and 8mm. Kelpak sprays were done as a tank mix with GA3 and CPPU same rates as Control. Season 2011-12: Two controls were tested, control 1 with GA3 20ppm @ 2-3mm, 30ppm @ 4mm, 40ppm @ 6 and 8mm. Control 2 was the same as control 2, but with Goëmar Calibra® at 3L.ha-1 at 6 and 12mm. The Kelpak treatments were one spray of 4.5L.ha-1 at 2-3mm and three sprays of 7L.ha-1 at 2-3, 4 and 8mm. All treatments were done with an electrostatic machine (ESS) with 70L of water per hectare. The blocks in which the trials were conducted had a history of high postharvest berry drop. The trial design was completely randomised with 4 replicates of 8 vines of which the middle 6 vines were used for measurements. Number of shot berries per bunch, berry size, weight, colour and firmness (FirmTech®) were recorded at harvest. Postharvest berry drop were recorded after packing as percentage by weight of berries without pedicels in the export 8.2kg boxes (USA standard). Results and Discussion POSTER PRESENTATIONS In the first year the Kelpak 4x4.5L.ha-1 treatment had a significant reduction of postharvest berry drop, 2.3% vs 4.2% of the control. The Kelpak 3x7L.ha-1 showed a similar trend with 3.4% berry drop, but was not statistically different to the control (Table 1). The increase of internal brush length had a high correlation with the berry drop, recording 1.2mm over the control (12.7 vs. 13.9mm) with the treatment of Kelpak 4x4.5L.ha-1. Kelpak 3x7L.ha-1 had no effect on brush length, the tendency to less berry drop was probably caused by an increase in flexibility of the rachis and pedicels flexibilities from this treatment. With these results we can predict that the most effective spray to reduce the berry drop is the 1st early spray at 2-3mm berry size. 172 7th International Table Grape Symposium Table 1. Effects of seaweed products on postharvest berry drop, season 1 (2010-11). Treatment Berry Drop (%) Brush length (mm) Control (GA3+CPPU+Calibra®) 4.2 a 12.7 b Kelpak 3x7L.ha 3.4 ab 12.7 b Kelpak 4x4.5L.ha-1 2.3 b 13.9 a -1 Values with same letters do not differ statistically significant at the 95% confidence level Due to the results of 1st year, it was decided to have controls with and without the Ascophyllum nodosum seaweed product (Calibra®) and a treatment with only one Kelpak spray (4.5L.ha-1) at 2-3 mm in the second season. Kelpak 1x4.5L.ha-1 at 2-3mm showed a similar reduction on berry drop to Kelpak 3x7L.ha-1 with the first spray starting at 2-3 mm (Table 2). Calibra® showed a tendency to increase the berry drop against control and significantly higher than the Kelpak treatments. Table 2. Effects of seaweed product on postharvest berry drop, season 2 (2011-12). Treatment Berry Drop (%) Control (GA3+CPPU) 6.0 bc Control (GA3+CPPU+Calibra ) 6.8 c Kelpak 1x4.5L.ha 3.5 a Kelpak 3x7L.ha 3.8 ab ® -1 -1 Values with same letters do not differ statistically significant at the 95% confidence level Conclusion The results show that Kelpak application at the early stage of 2-3mm berry size can be an effective tool to reduce the incidence of postharvest berry drop in certain table grape varieties without any collateral effect as: reduction on quality, harvest delay or postharvest condition. Acknowledgements We thank the technical assistant of Maria Alejandra Carreno and Agricola Los Acacios Ltda for all their help to successfully conduct this research. References Ben-Tal Y. 1990. Effects of Gibberellin treatments on ripening and berry drop from Thompson Seedless grapes American Journal of Enology and Viticulture 41(2): 142-146. Crouch IJ and Van Staden J. 1991. Evidence for rooting factors in a seaweed prepared from Ecklonia maxima. Journal of Plant Physiology 137: 319-322. Navarro M, Retamales J and Defilippi B. 2001. Efecto del arreglo de racimo y aplicación de CPPU en la calidad de uva de mesa Sultanina tratada con dos fuentes de giberelinas. Agricultura Técnica 61(1): 15-25. Retamales J, Cooper T, Bangerth F and Callejas R. 1995. Effects of CPPU and GA3 on fruit quality of Sultanina table grapes. Acta Horticulturae 394: 149-157. 173 POSTER PRESENTATIONS 7th International Table Grape Symposium ID 24 Abscisic acid (S-ABA) and sucrose effects on skin colour, anthocyanin content and antioxidant activity of ‘Crimson Seedless’ grape berries Giuseppe Ferrara1*, Andrea Mazzeo1, Angela Maria Stella Matarrese1, Andrea Pacifico1, Cesare Lasorella2, Rossana Punzi1, Antonio Trani1 and Giuseppe Gambacorta1 Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti - University of Bari ‘Aldo Moro’, via Amendola 165/A - 70126 Bari (Italy) 2 Dipartimento di Scienze Agro Ambientali e Territoriali - University of Bari ‘Aldo Moro’, via Amendola 165/A - 70126 Bari (Italy) *Corresponding author: Email: [email protected] 1 Background and Aims ‘Crimson Seedless’ is a table grape cultivar grown in several countries, which some years does not reach an adequate and commercially valuable red colour, probably as consequence of high temperatures in summer which negatively affect the synthesis of anthocyanins (Spayd et al., 2002). Cultural practices influence the colour of the berry skin, such as pruning, fertilisation, girdling, irrigation (Dokoozlian et al., 1995). Abscisic acid (S-ABA) is a plant growth regulator which has showed to be useful to overcome skin colour problems of ‘Crimson Seedless’ (and other cultivars) in various pedo-climatic conditions when applied from véraison onward (Peppi et al., 2007; Ferrara et al., 2013). Sucrose seemed to play an important role in the pathway of anthocyanins in grape cell suspensions and tissue cultures (Larronde et al., 1998; Hiratsuka et al., 2001), but probably with different mechanisms than S-ABA. The objective of this study was to verify the applications of S-ABA and sucrose, either alone or in combination, on the skin colour and the overall quality of ‘Crimson Seedless’ table grape. Experimental Procedure and Results Five-year-old ‘Crimson Seedless’ grapevines grafted onto 1103 P (V. berlandieri × V. rupestris) of similar vigour and crop load were used in the study. The experiment was carried out in the year 2012 in a commercial table grape vineyard located in the territory of Rutigliano (Puglia, Italy). A randomised block design was used with three blocks and six treatments (Table 1), and each treatment in the block consisted of three grapevines selected with a uniform number of bunches. Abscisic acid (400mg.L-1), as a commercial formulation of S-ABA (ProTone®), and sucrose (10%) were tested in two different times of application (at the beginning of véraison and one week later). At harvest, the following parameters were determined: commercially harvestable bunches (%), skin colour, chemical characteristics, S-ABA concentration either in the skin or the pulp of the berry, anthocyanin content, and antioxidant activity. Table 1. Treatments and time of application. Treatment Véraison T1 Control T2 400 mg.L-1 S-ABA T3 T4 400mg.L-1 S-ABA 400mg.L-1 S-ABA + 10% sucrose T5 T6 Véraison + 1 week 400mg.L-1 S-ABA + 10% sucrose 10% sucrose At first harvest, 60-80% of bunches were picked up from T2 up to T6, whereas only 30% from control. Better coloured bunches were obtained after treatments T2 and T4. Visual data were confirmed also by the colour meter measurements, with the h° lowest values (more red colour) for T2 and T4. Both treatments with S-ABA and sucrose did not influence the berry firmness at harvest. °Brix values did not show differences among treatments and at harvest ranged from 14.2 (T1) to 15.0 (T6). Titratable acidity and pH presented similar values among the treatments. S-ABA concentration was higher in skin than in pulp, as expected, with higher values in treated bunches but always below 1,000 ng/g f.w. of skin. S-ABA seemed to have also positive effects on the antioxidant activity of the berry and significantly increased the anthocyanin content, in particular the peonidin forms. POSTER PRESENTATIONS 174 7th International Table Grape Symposium Discussion and Significance of the Study The application of S-ABA and sucrose improved the colour of the berries and increased the amount of harvestable bunches at the first pick. Ripening parameters (°Brix, pH, titratable acidity) were not affected either by S-ABA or sucrose application, so the advanced harvest was due to colour improvement. Some bunches treated with sucrose (10%) resulted a little sticky, but this was probably a problem of the handheld sprayer and with the normal sprayers used in the vineyard this problem should be overcome. The results of this experiment seemed to confirm that applications of S-ABA at the right physiological stage (beginning of véraison) positively affected the skin colour of the berry. The effects of sucrose indicated its role in the biosynthesis of anthocyanins, but probably influencing a pathway different from the one involving S-ABA. In conclusion, S-ABA and sucrose improved the colour of the berry skin, with better results obtained when S-ABA was applied alone at the beginning of véraison. Positive effects were also measured for antioxidant activity and anthocyanin content. Acknowledgements The natural isomer of S-ABA used in these experiments was obtained from Valent BioSciences USA. The authors wish also to thank the Agriproject Group (Rutigliano) for its technical support in the field. References Dokoozlian NK, Luvisi DA, Schrader PL and Moriyama MM. 1995. Influence of trunk girdle timing and ethephon on the quality of Crimson Seedless table grapes. California Agriculture 49: 36-40. Ferrara G, Mazzeo A, Matarrese AMS, Pacucci C, Pacifico A, Gambacorta G, Faccia M, Trani A, Gallo V, Cafagna I and Mastrorilli P. 2013. Application of abscisic acid (S-ABA) to ‘Crimson Seedless’ grape berries in a Mediterranean climate: effects on colour, chemical characteristics, metabolic profile, and S-ABA concentration. Journal of Plant Growth Regulators 32:491-505 Hiratsuka S, Onodera H, Kawai Y, Kubo T, Itoh H and Wada R. 2001. ABA and sugar effects on anthocyanin formation in grape berry cultured in vitro. Scientia Horticulturae 90: 121-130. Larronde F, Krisa S, Decendit A, Cheze C and Merillon JM. 1998. Regulation of polyphenol production in Vitis vinifera cell suspension cultures by sugars. Plant Cell Reports 17: 946–950. Peppi MC, Fidelibus MW and Dokoozlian N. 2007. Timing and concentration of abscisic acid affect the quality of ‘Crimson Seedless’ grapes. International Journal of Fruit Science 7: 71-83. Spayd SE, Tarara JM, Mee DL and Ferguson JC. 2002. Separation of sunlight and temperature effects on the composition of Vitis vinifera cv. Merlot berries. American Journal of Enology and Viticulture 53: 171-182. 175 POSTER PRESENTATIONS 7th International Table Grape Symposium Author unable to attend Fumigation and cold treatment disinfestation methods CPF DeLima1,2 AgHort Analytics, 84 Queenscliffe Rd. Doubleview WA 6018, Australia. Tel. (+618) 63369516 Email: [email protected] 2 Formerly: Department of Agriculture and Food Western Australia 1 Background and Aims To access to high value overseas markets it is necessary to disinfest table grapes against quarantine pests. Cold treatments were researched over a number of years to find effective temperature x time combinations against fruit flies acceptable to overseas quarantine authorities and suitable for Australian industry. Because cold treatments were not effective against other quarantine pests, fumigation methods were developed using ethyl formate + carbon dioxide. Experimental Procedure and Results Test fruits: Red Globe (RG), Thompson Seedless (TS) and Crimson Seedless (CS) grapes were sourced from vineyards in NSW, VIC, SA and WA. Test insects: Mediterranean fruit fly (MFF), Queensland fruit fly (QFF), light brown apple moth (LBAM), red back spiders (RBS), long-tailed mealybug (LMB), two spotted spider mite (TSM), plague thrips (PT), and western flower thrips (WFT). Bioassay procedures were used to estimate doses and time exposure periods required for >99.9% effectiveness of cold treatments and fumigation. The selected doses were tested in semi-commercial trials. Assessments of toxicity of fumigant and cold treatment bioassay data were made by probit analysis (Finney 1971) using the GenStat package (GenStat 2008) with a generalised linear procedure. In large scale trials the upper 95% confidence limits for survival in the reefer tests were estimated using the methods of Couey and Chew (1986) in the cumulative Poisson distribution. Cold treatments: Trials were conducted on QFF and MFF at 1, 2 and 3°C against MFF and QFF. 90,000 grapes were infested for testing for cold exposure periods from 1 to 20 days to estimate LD50 and LD99 at each temperature to determine the most tolerant stage for each species. POSTER PRESENTATIONS Figure 1. Results of large scale disinfestation of Mediterranean and Queensland fruit flies at 1°C, 2°C and 3°C in Red Globe (RG), Thompson Seedless (TS) and Crimson Seedless (CS) grapes. There were no survivors in more than 100,000 treated insects at each temperature. 176 7th International Table Grape Symposium Large scale cold trials to prove efficacy at probit 9 (LD99.99683) were conducted to assess the most tolerant species. MFF disinfestation required 16 days at 1°C, 18 days at 2°C and 20 days at 3°C; whereas for QFF 12 days at 1°C and 14 days at both 2°C and 3°C were sufficient. MFF was found to be more tolerant to cold treatment than QFF as shown in tests required to achieve complete mortality in >100,000 insects (Figure. 1). The required temperatures for cold disinfestation were effectively maintained for 16, 18 and 20d at 1, 2 and 3°C respectively for large scale trials (De Lima et al., 2011) proving efficacy at probit 9. Verification trials using slightly higher temperatures requested by Japanese quarantine authorities to provide additional security were conducted from March to October 2012 and proved effective at 1.2, 2.2 and 3.2°C (Table 1) giving confidence in the methods and resulted in approval by Japan (February 2014) for import of Australian table grapes. Table 1. Number of pupae in treated and control fruits obtained in verification trials (March to September 2012) for cold disinfestation of Red Globe table grapes against Mediterranean fruit fly Ceratitis capitata (Wiedemann) at 1, 2 and 3°C. Actual average temperature of trial No. of fruits infested Total No. of pupae in control fruits Total No. of pupae in treated fruits Estimated % mortality (95% C.L.) 1.2 °C 1,600 28,295 0 99.9894 2.2 °C 1,600 28,173 0 99.9893 3.2 °C 1,600 31,001 0 99.9903 1.4°C 1,600 33,154 0 99.9909 2.2°C 1,600 21,296 0 99.9859 Cardboard cartons Polystyrene cartons Fumigation treatments: Laboratory fumigations were conducted to evaluate the relative tolerance of the stages of LBAM, TSM, WFT, PT, LMB and RBS likely to be found in exported grapes (De Lima, C.P.F. 2010). Tests were done in individually calibrated 6.5 to 7.1 litre glass desiccators fitted with magnetic stirrer bars at 10 and 15°C using at least 9 doses of ethyl formate + 10% CO2 to provide data on relative tolerance of selected stages. The temperatures in the cool chain considered most suitable for fumigation of grapes were 10 and 15°C. The LD50 and LD99 estimates provided the basis for dosages subsequently used in large scale tests. The decision on dose and time required for large scale trials was made by taking the LD99 upper 95% confidence level and increasing both by 25%. The large scale fumigation trial was conducted in a 40ft/12m (68m3) ISO refrigerated shipping container using Vapormate® in pressurised cylinders (16.7% EF + 83.3% CO2 BOC Gases Ltd.). Plastic or glass tubes (2cm diameter 5 - 15cm long fitted with plastic caps with 0.5cm vent hole sealed with filter paper) containing live insects were placed throughout the fruit held in open top cartons before fumigation. The insect tubes were retrieved after venting and reared to assess mortality. Fumigations were successful when final concentration was approximately 50% of the applied treatment dose. The refrigerated container satisfied the tests for gas tightness (De Lima 1994) with drop of applied pressure from 200 to 100 Pascals >15 seconds and was suitable for fumigation with Vapormate®. Comparison of LD50 and LD99 of the stages most likely to be found in exported produce provides an assessment of the relative toxicity of fumigation treatments (Table 2). In LD50 estimates, the LABM 1st - 3rd instars had about the same tolerance as RBS 1st - 3rd instars; both species were approximately 5-9x more tolerant than LMB, 3-4x WFT and PT, and 2x times TSM; but at LD99 TSM required the highest EF dose. The 15°C LD99 upper CL95% doses (g/m3) required were: RBS 32.35, LBAM 34.8, LMB 11.42, TSM 39.55, WFT 14.13, and PT 13.58. LMB crawlers were the least resistant spp. and stage and an assessment of relative toxicity of the other spp. showed that at 15°C LABM was x3.05, RBS x2.83, TSM x3.46, WFT x1.24 and PT x1.19 more resistant than LMB to the treatment. At 20°C, generally less EF was required to kill arthropods than at 15°C, but this was not the case for RBS where tolerance was slightly higher at 20°C than at 15°C due perhaps to indifference of RBS to the 15-20°C temperature range. 177 POSTER PRESENTATIONS 7th International Table Grape Symposium Table 2. Toxicity of ethyl formate + carbon dioxide to insects and spiders fumigated in the laboratory at 15 and 20°C for 2h at the stages likely to be present in table grapes. Relative toxicity ratios are given with respect to the doses required to kill LTMB at the LD99 upper 95% CL. Species and stages tested were: RBS 1st - 3rd instars; LBAM 1st - 3rd instars; LTMB crawlers; TSM adults; WFT adults; PT adults. Test species LBAM RBS LTMB TSM WFT PT Test °C No. tested Slope ±SE LD50 (g.m-3) ±95% CL LD99 (g.m-3) ±95% CL 15°C 15,492 10.05±1.99 18.25 (16.91 - 19.42) 32.16 (30.17 - 34.80) 20°C 12,842 4.34±1.46 15.80 (14.41 - 16.90) 24.51 (22.79 - 27.15) 15°C 2,400 8.42±1.76 18.54 (17.38 - 19.57) 29.95 (28.16 - 32.35) 20°C 2,384 8.44±1.75 17.64 (16.40 - 18.74) 31.04 (29.11 - 33.58) 15°C 11,295 4.91±0.71 3.75 (3.44 - 4.05) 10.17 (9.23 - 11.42) 20°C 15,148 5.55±0.98 1.80 (1.52 - 2.05) 4.85 (4.28 - 5.68) 15°C 11,065 2.55±0.55 9.30 (8.15 - 10.41) 33.99 (29.96 - 39.55) 20°C 12,723 3.19±0.59 10.59 (9.37 - 11.76) 31.93 (28.20 - 37.21) 15°C 19,224 4.81±0.74 5.38 (4.95 - 5.79) 12.75 (11.70 - 14.13) 20°C 24,226 5.73±0.91 4.83 (4.39 - 5.25) 11.36 (10.34 - 12.73) 15°C 19,825 4.84±0.75 5.42 (5.00 - 5.83) 12.26 (11.25 - 13.58) 20°C 24,935 5.27±0.83 4.58 (4.11 - 5.01) 9.69 (8.77 - 10.99) Since adult TSM were the most tolerant species and stage present in the export simulation it was decided to use 40g.m-3 EF for 2h at 15°C as a basis for the large scale test and increase both dose and time by 25%, thus requiring 50g.m-3 EF for 2.5h fumigation at 15°C. The applied dose was 36kg Vapormate® introduced as 2 lots of 18kg (nominal dose 88.4g.m-3 EF) in a 68m3 reefer intended to obtain 50g.m-3 EF (about 56% of initial applied dose) in free space after sorption. The treatment time was 2.5h and total time was 240 minutes including equilibration time of 60min and venting time of 30min. The loading was 432 x20 litre cartons each containing 10kg grapes giving 12.7% by volume and 63.5kg.m-3 by weight in 68m3. The applied Vapormate® temperature was volatilised to 142°C at the entry point into the reefer. The average amount of fumigant in air was 52.6g.m-3 EF and 21.6% CO2 and the final concentration was 26.8g.m-3 EF and 17.5% CO2 giving a cumulative dose of 687.17g.h.m-3. The treatment was conducted during the cool chain simulation cooling from 20°C to 15°C. Average initial temperatures were: air 18.1°C and fruit 21.8°C; final temperatures were: air 14.5°C and fruit 16.2°C. All insects were killed (Table 3) and the estimated mortality at 95% CL was > 99.91%. Table 3. Large scale fumigation of table grapes. Test fruit in cartons containing insects and spiders at the stages likely to be present in table grapes were fumigated with Vapormate® in a refrigerated shipping container (68m3) for 2.5h starting at 20°C and cooling to 15°C. The applied dose was 52.6g.m-3 EF + 21.6% CO2.Treatment time was 2.5h plus 1h equilibration and 0.5h venting (cumulative dose 687.17 g.h.m-3). Species Stages Number Treated Number Surviving Estimated % mortality (95% C.L.) Red back spiders 1st - 3rd instars 3,739 0 99.92 Light brown apple moth 1 - 3 instars 4,124 0 99.93 crawlers 3,682 0 99.92 Two spotted mite adults 5,163 0 99.94 Western flower thrips adults 3,506 0 99.91 Plague thrips adults 3,771 0 99.92 Long tailed mealybug POSTER PRESENTATIONS 178 7th International Table Grape Symposium st rd Discussion and Significance of the Study The results show that quarantine pests in harvested grapes can be killed without disrupting the cool chain process and that optimum quality can be maintained. The results provide new information on quarantine application of EF+CO2 and cold disinfestation for access of Australian table grapes to overseas markets. Acknowledgements The technical assistance of Emma Mansfield, Phillip Jackson, Tracey Liebregts, Caroline Lee, Simon Linacre, Mirjana Banovic and Jenny Lynch is gratefully acknowledged. Statistical advice was provided by Ms Jane Speijers. This project was funded by the Department of Agriculture and Food Western Australia, the Australian Table Grapes Association, Horticulture Australia Limited, and the Department of Agriculture Fisheries and Forestry Australia. References Couey HM and Chew V. 1986. Confidence limits and sample size in quarantine research. Journal of Economic Entomology 79: 887-890. De Lima CPF. 1994. Improved procedures for fumigation of oaten hay in shipping containers. In: Highley, E., Wright, E.J., Banks, H.J., and Champ, B.R. (Eds.). Proc. 6th Int. Wkg. Conf. Stored Prod. Prot., Canberra, Australia, vol. 1: 71-77. De Lima CPF. 2010. Fumigation of table grapes for export. Final project report TG04003. ©Horticulture Australia Limited. 52p. De Lima CPF, Jessup AJ, Mansfield ER, Daniels D. 2011. Cold treatment of table grapes infested with Mediterranean fruit fly Ceratitis capitata (Wiedemann) and Queensland fruit fly Bactrocera tryoni (Froggatt) Diptera: Tephritidae. New Zealand Journal of Crop and Horticultural Science 39:2 95-105. Finney DJ. 1971. Probit analysis. 3rd Ed., Cambridge University Press, Cambridge, U.K. GenStat 2008. Release 11.1 VSN International Ltd. Rothamsted, UK. 179 POSTER PRESENTATIONS 7th International Table Grape Symposium Author Index A Daus, A 47, 101, 105 H Abuzar, M 106 Davies, C 68 Halaly, T 93, 96 Achampong, AK 96 Degani, O 47 Hamacek, Edward L 65 Acucci, C 74 DeLima, F 118,176 Hashim-Maguire, Jennifer 56 Adams, Caroline 123 Deltondo, Angelo 112 Henriquez, JL 62, 124, 153, 165 Amendolagine, Antonio Maria 28, 97 De Tommaso, Bartolomeo 43 Hopkins, Rick 82 Dias, JP 134 Arroyo, JC 62, 124 Hurley, JM 139 Di Gennaro, Domenico 28, 97 Di Lorenzo, Rosario 24, 43 J Dixon, Christopher 114 Bahar, A 105 Jessup, A 118 Domingos, Sara 70 Bennett, Richard 20 Jones, Gregory V 17 Dry, Ian B 35 Jones, TM 139 Bhattarai, SP 130 E K Boss, P 68 Edwards, Everard J. 168 Kania, E 153 Böttcher, C 68 Espindola, Rodrigo 53 Kaplunov, T 47, 101, 105 B Berkowitz, Oliver 85 Bustos, Lisando 53 C F Kilmister, Rachel L. 168 Feechan, Angela 35 Callejas, R 153 KoilKonda, P 96 Fernandes Moura, Mara 132 Cameron, Ian 39 Konnerup, D 87 Ferrandino, Alessandra 127 Cardoso, Vânia 70 Ferrara, G 26, 74, 174 L Carlomagno, Antonio 127 Ferreyra, Raúl 146 Langer, A 124 Carreño, I 37 Fidelibus, Matthew W 56, 94 Larrain, P 172 Carreño, Juan 37 Fioretti, Michele 145 La Sorella, Cesare 26, 43 Casanova, Francisco 80 F Lourens, Adriaan 143 Learmonth, Stewart 136 Casieri, Arturo 145 Foyer, CH 87, 91, 109 Leesch, JG 139 Cecilia Peppi, M 153 Fracchiolla, M 26 Leitão, António E. 70 Clark, John R 48 Fritts Jr, Robert 80, 82, 154 Lichter, A 47, 101, 105 Clingeleffer, Peter 39, 102 Coêlho de Lima, Maria Auxiliadora 141 Coelho de Souza Leão, Patricia 84, 134, 141 Collie, Helen 136 Colmer, TD 87 Considine, JA 85, 87, 91 Considine, Michael 85, 87, 91, 109 Corena, Pat 35 Crane, O 96 D Dahal, Kishor C 130 Da Trindade, DC 134 180 Kedrina, Olga 127 7th International Table Grape Symposium G Lima, MAC 134 Lopresti, John 120 Gallo, V 74 Lourens, Adriaan F 143 Gambino, C 24 Lurie, S 105 Gentilesco, Giovanni 28, 97 Luvisi, Donald A. 56 Gil, Pedro 53 Gispert, Carmen 33, 60 M Golding, J 118 Mackenzie, Don 35 Gomes da Trindade, Danielly Cristina 141 Maldonado Araneda, Eduardo 114 Gordon, Colin 39, 87, 109 Goulao, Luis F. 70 Maldonado Cortes, Katerina 114 Maoz, I 47, 105 Masi, Gianvito 28 Mastropirro, A 26 Matarrese, AMS 74 Maturana, Gonzalo 80 Mazzeo, A 26, 74 Q U McAllister, A 106 Qian, Yaming 171 Ugalde, P 165 McCarthy, Belinda 39 Quiroz, P 124 Unwin, Dale J 168 McConchie, Cameron 39 R V McCormick, Roy 154 Raban, E 47, 105 Valdivieso, V 124 McWaters, Allan D 149 Racsko, Jozsef 80, 82 Valentim, Marcella Setúval 141 Medicamento, Umberto 145 Ramalho, José C. 70 Van Jaarsveld, Alwyn 123 Meitha, K 87 Reuveni, M 62 Vasquez, Stephen J. 94 Midmore, DJ 130 Reynolds, Schalk 80, 82 Vega Mayor, Sergio 53 Missenden, Brendan P 65 Rolshausen, Philippe E. 60 Velappan, Y 91 McClymont, L 106 Mollah, Mahabubur 168 Villalta, Oscar 120 Montemurro, P 26 S Montenegro, F 147 Scafidi, Pietro 24, 43 W Morales, Michelle 146 Scaloppi Júnior, Erivaldo José 132 Walker, Rob 39 Muhareb, JS 139 Schröder, Michael 154 Walsh, KB 130 Mujica, MF 147 Sellés, Gabriel 146 Wang, Xicheng 171 Mundaca, Sergio 53 Sheffield, K 106 Wang, Zhuangwei 171 Singh, Davinder 102 Weksler, Hovav 51, 101 N Smilanick, Joseph L 33, 139 Whitfield, D 106 Nóbrega, Hugo 70 Somma, Stefano 43 Wu, Weimin 171 Novello, Vittorino 127 Sommer, Karl J. 168 O Sosnowski, Mark R. 59 X Strydom, Janéne 76 Xu, HY 158 Oag, David R 39, 65, 130, 149, 151 Sun, L 158 O’Connell, M 106 Sun, XR 158 Y Oliveira, Cristina M. 70 Swinburn, Garth 162 Yan, AL 158 T Z Tarricone, L 28 Zhang, GJ 158 Tarricone, Luigi 97 Zhao, Minzhen 171 Pacucci, C 74 Tebbets, JS 139 Zheng, C 93, 96 Paioli Pires, Erasmo José 132 Tecchio, Marco Antonio 132 Zhu, BQ 158 Parron Ojeda, David 154 Terra, Maurilo Monteiro 132 Zutahy, Y 47, 101 Partington, Debra 120 Zutchi, Y 105 Peacock, William L 33 Thalavaisundaram, Swaminathan 112 Perl, A 47 Thomas, Mark R 35 Pienaar, Johan 80, 82 Tomkins, Bruce 120 Pinto, Manuel 146 Tornello, Giuseppe 143 Pitt, Kristen 102 Tornel, M 37 Pugliese, Franco 53 Treeby, Michael 102 Or, E 93, 96 Oren, O 96 P Pugliese, María Beatriz 53, 147 7th International Table Grape Symposium 181 Notes 182 7th International Table Grape Symposium Notes 7th International Table Grape Symposium 183 Notes 184 7th International Table Grape Symposium A big thankyou to our sponsors Platinum Gold Welcome Function Sponsor Victorian Technical Tour Sponsor Bronze Symposium Gala Dinner Sponsor Poster Session Sponsor Palms Vineyard Tour Luncheon Sponsor Delegate Satchel Promotional Inserts Product Donations In Kind Support Dinner Cruise Sponsor Paringi Morning Tea Sponsor Thank you for attending the 2014 symposium. We hope you have enjoyed your stay in Mildura and look forward to seeing you at the 8th International Table Grape Symposium.
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