Anthracnose is caused by Colletotrichum trifolii , a fungus which produces masses of tiny spores on infected stems and crowns. During periods of hot, rainy weather, spores are splashed from infected to healthy plants. Lesions develop on stems, causing stems to wilt and eventually die. The pathogen grows from stem tissue into the plant crown, and causes a crown rot which ultimately kills the plant.
Lesions have a straw-colored center with a dark brown border.
Black specks can often be seen within the center portion of the lesion. Anthracnose stem symptoms are relatively easy to differentiate from those caused by Verticillium and Fusarium wilts. With Verticillium and Fusarium wilts, the upper stem usually remains erect. Internodes are shortened and upper leaves are smaller than normal and are frequently curled or twisted. Figure 4 shows a comparison of anthracnose and Fusarium wilt symptoms from plants in the same field.