Distribution and molecular characterization of potato virus Y (PVY) strains infecting potato (Solanum tuberosum) crop in Kashmir (India)

Virusdisease. 2021 Dec;32(4):784-788. doi: 10.1007/s13337-021-00722-2. Epub 2021 Jul 31.

Abstract

For breeding resistant cultivars, understanding the nature and distribution of PVY strains is indispensable. In present study, during the course of survey two hundred potato samples showing symptoms of vein clearing, mosaic, stunting, mottling, curling and vein banding were collected from 4 major potato growing districts of Kashmir valley. The disease incidence ranged from 16 to 27.33% with maximum in district Srinagar (27.33%). All the samples were serologically tested for PVY infection using DAS-ELISA and 74 tested positive for PVY infection. Out of 74 positive samples forty samples were re-confirmed by RT-PCR by amplifying 900 bp using coat protein (CP) gene specific primers. The PCR-positive samples were further characterized into different strains using strain specific primers. The strains NTN, N and O were reported and among them NTN strain was found to be most prevalent throughout the valley. The phylogenetic analysis of selected isolates carried out with known PVY strains also confirmed that the isolates belong to the N, NTN and O strains of PVY. The study will help in developing point of care strain specific diagnostics and also in devising the strategy for developing PVY resistant varieties, because when we have the complete information about the virus and its strains it will help us in screening the germplasm against each strain and, therefore, eventually development of a multi-strain resistant variety.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-021-00722-2.

Keywords: Distribution; Potato; Potato virus Y; RT-PCR; Strain.