Black spot of sweet potato mainly harms potato seedlings and tubers. At the initial stage of infection of potato seedlings, spindle-shaped or rectangular slightly concave black spots were produced in the underground part or stem base of young stems, which gradually spread underground and became longitudinal lesions, and continued to expand, making the stem base of seedlings completely black. Soon after the diseased seedlings were planted, the leaves turned yellow and the plants were short, and finally the diseased plants rotted in the ground. The initial lesion site of potato is a round or nearly round concave gypsum-like lesion with solid and clear boundaries, with gray mold layer or black hair in the middle. In severe cases, the lesions merge into irregular shapes. The pathogen goes deep into the lower layer of potato meat, making potato meat dark green and bitter. The affected part is lignified, hard and dry.

If it is black spot disease, it should be bitter, and there will be symptoms of deterioration and mildew. The black spots on your sweet potato skin are not necessarily black spots. But in order to ensure safety, it is best not to eat. . After all, health is more important. Be nice to yourself.