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.
3. Progress Report
Field trials were planted in New York, Wisconsin, and Idaho to screen potato breeding lines for PVY resistance. Fourteen breeding lines from nine breeding programs across the U.S. will be evaluated for foliar symptoms during the growing season and then at harvest for any necrotic tuber symptoms. The trials are set up to evaluate three strains of PVY, one of which is known to cause tuber necrosis. Samples of PVY infected potato cultivars from Idaho fields were collected and typed to PVY strain using an RT-PCR assay. This part of the research is to develop PVY symptom photos specific to cultivar and PVY strain that will be used to educate the industry to recognize the range of symptoms caused by PVY. This research addresses objective 4 of the in-house project to characterize potato cultivar response to new strains of Potato virus Y (PVY) and to identify new sources of resistance useful to potato breeders. Monitoring methods include meetings, reports, and correspondence through e-mail and phone.