Start Date: Dec 15, 2008
End Date: Dec 14, 2011
Recent studies have identified an explosion of genetic and biological diversity in the Potato virus Y (PVY) population leading to a widespread distribution of damaging necrotic variants that were recently considered to be absent in North America. Nevertheless, the population structure, recombination potential, and pathogenicity of PVY strains in different environments and in prominent potato varieties remain poorly understood. Two of the co-PIs were the coordinators and principle scientists for a 3-year (2004-07) survey of PVY diversity in all U.S. and Canadian seed potato production areas. More than 4,000 PVY isolates were analyzed by multiplex RT-PCR to determine a molecular phenotype, by enzyme-linked immunosorbent assays using a panel of monoclonal antibodies to determine a serotype, by bioassays on tobacco and potato to determine a necrosis phenotype. All of this information was used to categorize isolates into strain groups. Additionally, there is a growing list of collaborators willing to share representative PVY isolates from other continents. The research objective is to sequence a minimum of 2500 isolates that represent multiple individuals within each of the distinct strain groups. We will utilize both the standard bioinformatics platforms and develop unique tools to address PVY genomic diversity, phylogeny and evolution of PVY strains, and to correlate molecular phenotypes with biological phenotypes relevant to potato production and international and domestic marketing and trade. The results of the proposed research will directly result in the identification of molecular markers and sequences that can be used to develop new methods to detect and differentiate various novel PVY strains, and to quickly identify biological phenotypes. This information will also be invaluable for potato breeding programs focused on developing PVY resistance in potato and other susceptible crops.