Sharp eyespot of wheat
Sharp eyespot, also called spring blight, infects wheat in temperate regions of the U.S. It is caused by Ceratobasidium cereale. Tan, lens-shaped lesions with dark borders initially appear on the outer leaf sheath of lower stems, often between the crown and third node. Mature lesions eventually turn dark brown. Lesions result in formation of a hole in leaf sheaths. White fungal growth may be present in the lesion and light brown fruiting bodies may develop within fungal growth. Severe infection can result in the death of young tillers, lodging, and the formation of white heads. Wheat plants may eventually bend at infected nodes. Symptoms can be observed from stem extension stages through ripening.
Cool, damp weather near snow melt and continual wheat production under no-till systems increases disease risk. Conditions favoring wheat development do not generally favor sharp eyespot development.
Where available, use less susceptible wheat varieties. Crop rotation with a broadleaf plant or another non-host crop will reduce sharp eyespot risk.
Gallery images: J. Marshall