Phytophthora root and stem rot is a significant disease in many areas where soybeans are grown. In the early season, seedlings may be attacked and killed in the ground or soon after emergence. At seedling and later vegetative stages, infected stems appear bruised and soft, secondary roots are rotted, the leaves turn yellow, and brown and plants can wilt and die. It is important to recognize that Pythium is a related pathogen that causes similar damage and symptoms in seeds and seedlings. In the mid or late season, plants may die throughout the season. On infected plants, brown lesions form on the roots, the roots rot and degrade, and a dark chocolate-brown discoloration of the stem often extends from below the soil line upward into the lower parts of the plant. Leaves turn yellow, wilt, and typically stay attached after plant death. Plants are often killed in patches or in sections of rows.