More than 8,000 species of fungi cause disease in plants. In fact, most diseases found in both cultivated and wild plants are caused by fungi. Some pathogenic fungi grow and multiply in their host plants; others grow and multiply on dead organic matter and host plants. Fungi that are pathogenic to plants can occur below the soil surface, at the soil surface, and throughout the body of a plant. Fungi are responsible for leaf spots, blights, rusts, smuts, mildews, cankers, scabs, fruit rots, galls, wilts, and tree diebacks and declines, as well as root, stem, and seed rots.