Cercospora Leaf Blight and Purple Seed Stain of Soybeans
Field Facts by Steve Butzen
Cercospora leaf blight and purple seed stain is caused by the fungal pathogen Cercospora kikuchii, which attacks both the leaves and the seeds of soybeans. As a leaf blight, Cercospora is one of many diseases that can infect soybeans in late summer, usually with only minor effects on yield. As a seed disease, Cercospora diminishes seed appearance and quality, but usually does not decrease yields significantly.