Tobacco bacterial wilt, which is a kind of bacteria disease caused by Ralstonia solanacearum .E.F Smith and greatly affect tobacco product quality, is one of the most destructive disease on the threatening tobacco crop worldwild and is hard to control. So far using disease-resistant varieties is the most effective way to control this disease. Biovar, the physiological race and pathotype of R. solanacearum from native tobacco should be studied for breeding of disease-resistant tobacco varieties...