Identification Of Tobacco Potato Virus Y In Heilongjiang Province

Potato virus Y (PVY) is main diseases in tobacco in HeiLongjiang province. PVY can cause vein necrosis and seriously affecte the qulity and yield of tobacco. Few studies have been carried out to identificate PVY strains in China, even blankly in HeiLongjiang province.In this study, PVY isolates from HeiLongjiang province were divided into 4 strains by mainly using molecular methods combining serological method and biological method. The main results are as follows.1. PVY isolates from HeiLongjiang province were divided into 4 strains PVYNW, PVYN, PVYNTN and PVYNTN-NW by using multiplex RT-PCR. The PVY NTN-NW strain distributed most widely and was most predominant in HeiLongjiang province.2. The complete sequences of four PVY isolates (HLJ-SH8, HLJ-SC2, HLJ-SC6, HLJ-MDJ4) were obtained which contain 9698,9702,9702,9698 bases respectively and only one ORF composed of 9186 bases encoding a polyprotein including 3061 amino acids.3. The complete sequences of four PVY isolates and PVY strains registered NCBI were blasted, Phylogenetic trees were made, four PVY isolates were classified as PVYNW, PVYN, PVYNTN, PVYNTN-NW. It gives the same result as the multiplex RT-PCR.4. PVY isolates HLJ-SC2, HLJ-SC6 reacted with 1F5, revealing N serotype. HLJ-SH8, HLJ-MDJ4 reacted with MAb2, revealing O serotype.5. All of the four potato virus Y strains can cause vein necrosis at different degreeon of susceptible-infected tobacco. The virulence of the four PVY isolates were HLJ-SC2>HLJ-SC6>HLJ-MDJ4>HLJ-SH8.