Sweet potato virus disease is one of the common diseases of sweet potato, which starts from the seedling stage of sweet potato, and the disease of regenerated potato seedlings after cutting is more serious. The typical symptoms of diseased seedlings are: yellow leaves, atrophy, mosaic, rolled leaves, thinner stems and vines, and obviously weakened growth potential. After the diseased potato seedlings are planted in the field, the growth is weak and the yield is low, and the yield is generally reduced by more than 60%