Tobacco mosaic is a viral disease spread by aphids, thrips and whiteflies. Use mushroom proteoglycan (or lentinan) plus natural brassinolide plus octylamine acetate (or chlorobromoisocyanuric acid) plus zinc sulfate plus thiamethoxam (or acetamiprid) for prevention and control, and spray it on the leaves every 7~ 10 day for 2~3 times in a row to inactivate the virus, weaken its activity, inhibit its reproduction, and kill the virus and aphids, thrips and rice planthoppers that spread the virus.