In severe infestations, scattered plants or groups of plants show premature ripening (whiteheads) and stunting. The plants are easily pulled because the roots have rotted, in contrast to common root rot. Roots are blackened and usually a shiny black lesion extends up the stem. Less severely infected plants do not die prematurely but have brown to black lesions on the crown and roots.
Yield loss occurs because severely infected plants produce no grain or severely shrivelled grain. Less severely infected plants produce fewer heads and kernel weight is reduced.