With designed specific primers based on Potato leafroll virus(PLRV) coat protein(CP) gene sequence,one PCR fragment(about 0.6 kb) was amplified by reverse transcription polymerase chain reaction(RT-PCR) using the total RNA as template extracted from virus infected potato plant collected in Zhaotong,Yunnan province.The fragment was cloned into pGEM-T easy vector and sequenced.The sequence was compared with that of homologous gene of other PLRV isolates.The results showed it had high homology with the other isolates(the highest homology reached 99.2% of nucleic acid).Based on CP amino acid sequence the phylogenic tree of PLRV was established and the isolates were clustered into many groups.
