Method for isolation and identification of potato virus M, S, X, Y

The common procedure for isolation of potato virus M, S, X, Y, based on precipitation with PEG (final concentration of 6%) and purification by gel filtration on the Sepharose 2B is decribed. Identification of individual viruses is performed on the basis of electrophoretic analysis of viral coat protein, extracted from purified virus fraction. In electrophoresis coat proteins give single bands with the relative mobility of 1.0, 0.97, 0.94, and 0.80 for PVY, PVS, PVM and PVX respectively. Determination of protein or RNA content in virus fraction after chromatography allows the quantitative estimation of virus in plant material