Greenhouse comparison of two detection methods for potato virus YN-Wi at four potato growth stages

Abstract

Potato virus Y (PVY) causes significant crop and monetary losses. Owing to the prevalence of newly emerging strains of PVY such as PVYN-Wi, which often cause asymptomatic to mild reactions on certain potato cultivars, accurate tools are required to detect the virus in potato production. This study compared the sensitivity of a rapid field detection method (immunostrips) with a common laboratory detection method (triple antibody sandwich ELISA) on cultivar Chieftain, grown under isolated conditions in a greenhouse and mechanically inoculated with PVYN-Wi, at four potato growth stages (emergence, preflower, postflower, and senescence). Plants inoculated at emergence displayed severe symptoms of mosaic, veinal necrosis, and leaf drop. Plants inoculated at preflower, postflower, and senescence had veinal necrosis but low or no incidence of mosaic and leaf drop. Overall, few or no tuber symptoms were observed, but a trend of lower tuber yield occurred for emergence-inoculated plants. Low variability in PVYN-Wi detection occurred in both tests for emergenceinoculated plants, whereas those inoculated at preflower and postflower had more variability. Because symptom expression may differ depending on the growth stage when a plant becomes infected, these variations should be heeded with either detection method when collecting samples for PVY testing.