2007 Annual Report 1a.Objectives (from AD-416) The objective of this cooperative research project is to establish and maintain a 6-year planting of five replicates of an experimental subset of 120 vines from the cold hardy Vitis germplasm collection to be used in evaluation of disease resistance and other traits when grown in the environmental conditions of Fredonia, NY. These accessions have been propagated and planted for at least one year in a nursery. Establishment of the planting requires preparation of one-acre of land, laying out 2-wire trellising, liming the soil to at least pH 6.0, and planting the 600 vines. Maintenance activities will include installation of grow tubes as needed in the first season, standard fertilization, weed control, and pest control practices during all growing seasons, and pruning and tying vines during the spring, starting in 2006. 1b.Approach (from AD-416) Prepare 1-acre of suitable land at the Fredonia Vineyard Laboratory for planting 600 vines, including laying out 2-wire trellising, liming the soil to at least pH 6.0. Plant the 600 vines in the experimental design provided. Maintain the vines using standard practices, including installation of grow tubes as needed in the first seasonal; standard fertilization, weed control, and pest control practices during the spring, starting in 2006. 3.Progress Report This report serves to document research conducted under a specific cooperative agreement between ARS and Cornell University. Additional details of this research can be found in the report for the parent project 1910-21220-002-00 D, "Genetics and Genomics of Grape Rootstock and Scion Interactions with Pathogens." This SCA has the goal to establish and maintain a planting of five replicates of an experimental subset consisting of 120 vine accessions from the cold hardy Vitis germplasm collection to be used in evaluation of disease resistance and other traits when grown in the environmental conditions of Fredonia, NY. In the prior reporting period, we successfully completed the establishment of this unique vineyard. We completed the selection of diverse Vitis germplasm accessions representing North American, Asian, and European gene pools likely to express traits for variety improvement such as unique sources and mechanisms of disease resistance to economically important pathogens, including but not limited to powdery mildew (caused by Uncinula necator), downy mildew (caused by Plasmopara viticola), black rot (caused by Guignardia bidwellii), and phomopsis cane and leaf spot (caused by Phomopsis viticola). Following selection of these diverse accessions, we completed vegetative propagation and planting of the vines in Fredonia, NY, established the vines, and installed the structural framework and trellising of the vineyard. Five hundred seventy out of 600 vines survived their first two years in the vineyard and were trained to the top wire. The first set of disease resistance ratings were taken on the natural incidence of grape powdery mildew and grape downy mildew in 2006. Over 80% of the accessions in the experimental subset had no early season powdery or downy mildew infection in July 2006, while vines in the neighboring Concord vineyard showed frequent powdery mildew infection. Disease ratings were repeated in September 2006, with only 37 accessions being rated powdery mildew resistant and only 47 accessions rated resistant to downy mildew. The shift of individual accessions from being rated resistant early in the season to susceptible late season suggests selection for virulent isolates over the growing season and/or more favorable environment for infection during later months. Our current data supports the former hypothesis, as nearly half of the individuals rated powdery mildew susceptible in September 2006 were fully resistant to a single isolate of powdery mildew when controlled inoculations were conducted in controlled environments. Similarly, ten of the accessions susceptible to natural populations of downy mildew in September 2006 were resistant to a single isolate. Powdery mildew and downy mildew resistance data will be recorded again in 2007. This project was monitored through site visits.