Abstract:On the basis of host plant reactions, serology and analyses of nucleotide sequence of 1554 bp cDNA in the virus RNA 3‘ end, a Tobamovirus isolate from an infected oilseed rape plant was identified and characterized as a strain of Oilseed rape mosaic virus (ORMV), namely Wh strain. ORMV-Wh infected oilseed rape Brassica napus, Chinese cabbage Brassica pekinensis and other vegetable plants in family Cruciferae, had less infectivity to tomato, Lycopersicum eaculentum, eggplant Solanum melongena and other in family Solanaceae. ORMV-Wh is serologically distinguishable from TMV in ELISA test. Sizes of mp, cp genes and 3‘UTR of ORMV-Wh were 798 nt,474 nt and 235 nt, respectively, with overlapped 77 nt between mp and cp genes. Sequence identity of mp, cp genes and 3‘UTR of ORMV-Wh is all less 60% to those of TMV, higher than 80% to those of Tobamoviruses infecting Cruciferae plants, and higher than 90% to those of RMV-CAB,,RMV-Sh, YoMV, YoMV-Cg, CTMV-W, which are the strains of ORMV.