Survival of Flue-cured Tobacco TMV Through the Winter in Guizhou

The survival of tobacco mosaic virus (TMV) in different flue-cured plant residues and other host plants in Guizhou was studied. The result indicated that TMV was easier to survive when inhabiting inside soils than on soil surfaces. TMV survived longer in large roots than in leaves and stems, and it lived longer in stems than in leaves. TMV in stems and leaves submerged by water lost its infectivity after 10 months. Stems and stakes with TMV stored inside houses during the winter or in fields caused temporarily transplanted seedlings to be infected severely. The tobacco suckers with TMV lost its infectivity after 6~11 months, while they kept a lot of TMV as a cooked pig food. Regularly, the seed shells from tobacco plants with TMV had some virus to live, but it was not harmful to tobacco seedlings. TMV was just found in other host plants such as tomato, pimiento, cabbage and Solanum incanum. So we suppose that the over wintering hosts of TMV include tobacco stems and roots mostly, but the Solanum incanum is the wild and noticeable one. Therefore the main measures including taking tobacco residues away with reason, rotation and using sucker agents are very effective to prevent TMV.