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Collector's Edition WINES&VINES 145 WINE EAST GRAPEGROWING disks several times or use different strains of powdery mildew spores to test each one of the individual samples. These multiple "snapshots" allow us to characterize how robust the ob- served resistance is with better accuracy. A eureka moment! Phomopsis resis- tance identified The ability to use inexpensive sequencing tech- niques to identify thousands of markers and associate them with desired traits has already resulted in four newly released varieties in France with two powdery mildew and two downy mildew genes (see "ls Europe Starting to Embrace Hybrid Wine Grapes?" Wines & Vines, August 2018). It is interesting to note that information from one of these mapping populations also resulted in other surprising results beyond the VitisGen2 project's focus on powdery mildew. Technician Steve Luce was pruning a map- ping population at Cornell AgriTech for Bruce Reisch, professor of plant breeding and genet- ics in Cornell's department of horticulture, and noticed that another disease — phomopsis cane and leaf spot — varied in intensity. He recorded which siblings in the mapping popu- lation had severe disease symptoms and which had no symptoms. Because the project already had a marker-based map of the vineyard, graduate student Paola Barba was able to use his observations to identify two strong DNA loci for phomopsis resistance on the same day, literally within a few hours of receiving the data. This unanticipated, rapid and useful re- sult further demonstrates the power of having the detailed genetic information available. To date, the VitisGen project has identified more than 70 new marker-trait associations not only for disease resistance, but also for fruit-quality attributes such as anthocyanin modifications, skin color, sugar and acid con- tent. Inexpensive DNA sequencing techniques, establishment of 12 mapping populations, and field/laboratory phenotyping are the resources that made it possible. The payoff of these new markers will be better tools for breeders and more high-quality, disease- resistant varieties in the pipeline for current and future generations of grapegrowers. This research was supported by the USDA-NIFA Specialty Crop Research Initiative (Award No. 2017-51181-26829). Dr. Tim Martinson is senior extension associate at Cor- nell University. Dr. Lance Cadle-Davidson is a research plant pathologist with the USDA Agricultural Research Service's Grape Genetics Research Unit, based at Cor- nell AgriTech. To see references and acknowledgements for this article, go to winesandvines.com and search under Magazine › Features › December 2018. DISTRIBUTOR MARKET SERVICE A new data service from Wines Vines Analytics Looking to improve your distribution strategy? Make better, more informed decisions with Distributor Market Service. WINES VINES ANALYTICS DISTRIBUTOR MARKET SERVICE Contact us for a free demo or to learn more (707) 940-3922 • DMS@winesandvines.com • www.winesandvines.com/marketing/dms • Over 1,400 North American distributor profiles containing contact info, corporate linkage and more. • Identify potential distributors based on the demographics of their winery portfolio. • View winery and distributor performance in a state based on quarterly IRI off-premise sales summary data. • Advanced search and export capabilities via online user interface.