Planting a Problem: Examining the Spread of Seed-Borne Potato Virus Y

Potato virus Y (PVY) is among the most economically impactful potato pathogens, yet the spread of PVY from infected seed potatoes within commercial potato fields has not been adequately studied. Test lots containing various seed-borne PVY levels were created by mixing different proportions of seed pieces from healthy and infected tubers drawn from the same seed source. These seed lots were planted in commercial potato fields near the Teton Seed Potato Management Area from 2010 to 2012. Regression analyses on data from these test plots produced models of the in-season spread of PVY originating from infected seed. Conventional ordinary least squares techniques were supplemented with the use of quantile regression; the resulting models indicate the significance of seed-borne PVY on end-of-season infection levels and highlight the need of seed potato buyers to review postharvest testing results.