2. Sweet potato varieties: the varieties with large potato pieces are heavy.
3, sweet potato infection: stem nematodes, endangering potato pieces, causing cracking. Sweet potato stem nematode is mainly transmitted through seed potato and soil, and both potato pieces and potato vines will suffer. If the potato is damaged, if it is spread by diseased seedlings, the skin generally has no obvious symptoms, but the inside turns brown and white; In case of soil transmission, nematodes invade the potato cuticle, and the cuticle of the affected area first fades, then turns green, slightly droops or has small cracks, and the subcutaneous tissue turns brown and shrinks, and then gradually develops into small cracks. With the growth of roots, nematodes damage from all sides to the center, forming chaff rot inside, forming large cracks and dark brown halo or water stains in the stratum corneum.