Classification of Virus Disease Symptoms, Kinds of Virus Species and Types of Infection of Virus on Maryland Tobacco

Wufeng county in Hubei province is the only Maryland tobacco planting area in China. Maryland tobacco virus diseases were investigated there in 2011. The symptom types of virus diseases could be divided into 4 main kinds, including mosaic, distortion, vein necrosis, etching, which were identified through indication plants for virus species. DAS-ELISA was applied to identify the virus species to the collected 57 samples. It demonstrated that the virus species which infected Maryland tobacco included TMV, CMV, PVX, PVY and TEV. The detection rate of TMV was maximal among all the tested samples, and PVY took the second place. Meanwhile it commonly occurred that two and more kinds of virus co-existed, and TMV+PVY, TMV+CMV+PVY were the main patterns.