2010 Annual Report 1a.Objectives (from AD-416) Potato virus Y (PVY) is a serious disease problem in the seed potato crop. The seed potato industry set goals to reduce PVY incidence and to eliminate where possible the new tuber necrotic isolates. Our objectives are to assist seed certification agencies in methods for detecting and eliminating PVY from seed stocks, assist breeding programs in identifying PVY resistance, and to assist growers in developing cost effective, on-farm virus control strategies. 1b.Approach (from AD-416) Training materials will be developed to help inspectors better identify virus infections. Improvements to post harvest test procedures will focus on lighting systems that may allow operations to move out of the field and into controlled environments that would allow more uniform growth and faster testing. An economic analysis of various post harvest test methods will provide certification agencies with cost savings projections if they choose to implement new testing procedures. Field and greenhouse evaluations of existing cultivars and breeding lines for their susceptibility to tuber necrosis and their reactions to all PVY strains will provide valuable risk assessment information. Regional trials of material should also identify new sources of resistance to PVY that can be introduced into breeding populations. Cost-benefit analyses will be conducted for each of the scientific recommendations in order to assist agencies in evaluating any proposed changes to the National PVY Management Plan. Proposal Co-Investigators will meet annually with stakeholders to ensure the research continues to address relevant issues and to discuss research findings and potential recommendations to modify the current PVY Management Plan. Documents Reimbursable with CSREES. Log 38903. Specialty Crop Research Initiative. 3.Progress Report This research addresses objective 4 of the in-house CRIS to characterize potato cultivar response to new strains of Potato virus Y (PVY) and to indentify new sources of resistance useful to potato breeders. A set of putatively resistant PVY clones and cultivars was established from nine potato breeding programs in the U.S. Agreements were set up with the breeding programs to produce minitubers of these potatoes to be supplied in the fall of 2010 for replicated field trials in 2011. The objective of these field trials is to screen for PVY resistance in three locations across the U.S. Results will be used to identify useable resistance in the U.S. potato breeding programs and to better characterize new cultivar response to PVY.