Detection of Potato Viruses Y and A in Tubers by Enzyme‐Linked Immunosorbent Assay after Natural and Artificial Break of Dormancy

Abstract

AbstractThe effects of natural and artificial break of dormancy on the detection of potato viruses Y (PVY) and A (PVA) in tubers of field‐grown potato cultivars with primary and secondary infections were studied by enzyme‐linked immunosorbent assay (ELISA). Both viruses were at low concentration and unevenly distributed in dormant ‐tubers. Four to six weeks after treatment with Rindite, maximum concentrations of PVY and PVA were detected at both tuber ends with generally higher values at the rose end than at the heel end. Slower and smaller virus increase and a retarded and/or limited virus translocation were observed in treated tubers of resistant cultivars. Consequently, detectability of PVY and PVA was higher in tubers of susceptible cultivars than in those of the resistant ones. Detection of both viruses was very difficult and unreliable in tubers after natural break of dormancy. The very low concentration of PVY and PVA in dormant tubers and their drastic multiplication in Rindite‐ treated tubers appear to be characteristic of potyviruses and are unique among the major potato viruses.