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Cercospora leaf blight

Area of impact: Leaves pods and seeds

Description: Red-brown spots on leaves stems and pods that can merge to form large lesions. Leaves look "sunburned." Seeds develop purple or pink spots and patches known as purple seed stain. However, infected seeds do not always show symptoms.

Pathogen involved: Cercospora kikuchii (a fungus)

Timing/Conditions: Occurs from flowering to maturity during warm humid weather.

Contributing factors: Overwinters in soybean tissue and infected seeds.

Management practices: Use pathogen-free seeds foliar and seed treatment fungicides and rotation out of soybeans

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