Ring spot, black blight

Symptoms

All aboveground portions of the plant may show symptoms. Individual lesions have dark concentric rings, from black fruiting bodies, with definite edges surrounded by a yellowish zone. Under severe attack, spots coalesce, and the entire plant may be affected and blackened. In seed stalks, the fungus causes a distortion similar to the injury caused by the herbicide 2,4-D. Dark lesions may develop on stored cabbage and may penetrate deeply.