Cercospora Leaf Blight - Agronomic Impact

Cercospora leaf blight and purple seed stain generally do not affect yields in the North Central region. Photo credit: L. Giesler, University of Nebraska

Cercospora leaf blight, caused by Cercospora kikuchii, is generally not yield limiting in the North Central region.

Seed infection by Cercospora and the resulting purple discoloration does not reduce yield directly. However, a high percentage of stained seed may reduce the value of the crop, result in grain dockage, or in denial of seed certification.

Planting seeds infected by Cercospora kikuchii, or it's close relative C. sojina (frogeye leaf spot) may result in delayed or reduced germination and poor seedling vigor.