Serological Identity of Potato Virus X (PVX) and PCR Characterization of Its Coat Protein (CP) Gene

Potato virus X (PVX) is among top ten most economically damaging plant viruses in the world and its increasing incidence is getting an alarming situation in potato crop of Pakistan. During two consecutive years (2010-11 and 2011-12), the incidence of PVX was recorded in potato fields at Rawalpindi, Islamabad, Faisalabad and Sahiwal. The samples were collected and subjected to Double Antibody Sandwiched (DAS) Enzyme Linked Immunosorbant Assay (ELISA) and average incidence of PVX was determined about 16.86% (OD 405nm 1.38) during 2010-11 and 27.10% (OD 405nm 0.479) in 2011-12. The infectivity of the virus was assayed through mechanical inoculation on Nicotiana tabacum cv. Samsun, N. rustica, Datura stramonium, Chenopodium sp. Gomphrena and Capsicum annuum producing local lesion, mosaic and mottling symptoms. Coat protein (CP) gene specific sense and antisense primer successfully amplified a 750bp fragments through Polymerase Chain Reaction (PCR) assay.