Examining potato Virus Y (PVY) in the first field season of the University of Minnesota potato breeding program

University of Minnesota M.S. thesis. December 2013. Major: Applied Plant Sciences. Advisor: Christian A. Thill. 1 computer file (PDF); viii, 69 pages.Potato virus Y (PVY) reduces yield and tuber quality of potatoes. In potato breeding, PVY can compromise evaluation of germplasm by masking the genetic potential of potato genotypes. If PVY incidence is high among hybrids grown in their first field season (nuclear seed), genotypes with potentially desirable traits may be discarded because of PVY infection; thus, reducing the genetic variability in this population. Prior to this study, the University of Minnesota Potato Breeding Program had not tested nuclear seed for PVY. This study investigated PVY incidence at three field locations from 2007 to 2009. Following leaf sampling and serological testing, PVY incidence was high (greater than 0.5%) at all locations in all years. The average PVY incidence was greatest in samples collected late in the growing season from samples near PVY inoculum. Grand Forks, MN (leaves collected 30 Sept. 2008) had the highest number (32.7%) of samples positive for PVY