Abstract
Potato virus caused 83% yield losses in potato crops of Pakistan. Potato virus X (PVX) is in the list of the top ten damaging plant viruses in the world. Thirty yhree varieties/advanced lines of potato were screened against potato virus A (PVA), potato leaf roll virus (PLRV), potato virus M (PVM), potato virus S (PVS) and PVX. CIP-72-Y-3 was infected with PVA, PVM, PVS and PVX while Sahiwal-3, 34-1-Y, Sahiwal-4, 34-2-Y, Sahiwal-5, Sahiwal-6 and CIP-72-Y-4 showed reaction against PVA, PVS and PVX. 34-Y-3 found positive against PVA and PVX while PVM and PVX were confirmed in 34-4-X and CIP-72-Y-1. Azado-3, 34-6-X and 36-2 were positive with PLRV and PVM. 36-1, 34-S-1, 34-S-3-H and 42-1(Rusal Invary) were infected with PLRV and PVX while PVS and PVX were detected in Sahiwal-2, Azado-2, 42-2 (Rusal Invary) and CIP-72-Y-2. Eleven, one, nine, two, eight and two varieties/advanced lines of potato were highly resistance, highly susceptible, moderately susceptible, resistance, susceptible, against PVX respectively. Coat protein (CP) gene specific primes successfully amplified a 750 bp fragment of PVX in infected samples.
