Molecular Detection of Potato Leaf Roll Polerovirus through Reverse Transcription Polymerase Chain Reaction in Dormant Potato Tubers

A Reverse Transcription-Polymerase Chain Reaction (RT-PCR) technique was applied for the detection of Potato leaf roll polerovirus (PLRV) in dormant potato tubers. A primer pair was designed from the coat protein-encoding fragment of the PLRV genome that amplified a 336-bp product. The amplified product was detected in nucleic acid preparations from leaves and tubers of 5 cultivars and from purified virions. The specificity of the RT-PCR product was confirmed through southern blot analysis. The primer pair used in the RT-PCR did not produce any nonspecific product from 7 other potato viruses. Sensitivity of RT-PCR was confirmed by detecting PLRV from known mixture of PLRV and randomly selected potato virus. Dilution of 1:1000– 1:4000 and 1:200–1:1000 were used to detect viral load from foliage and tuber, respectively. RTPCR efficiently detected PLRV in sprouting tubers as well as dormant tubers stored at 20– 25°C for 4 months.