Purple Seed Stain of Soybean


Purple Seed Stain of Soybean

Cercospora kikuchii


In a Nutshell

    Mottled purplish to brown discoloration of the upper leavesRed-brown spots may also appear on stems and podsPink to purple discolorations varying in size (from spots to large patches) on the seedsGermination rates and seedling emergence may be affected

Hosts: %1$s

· Soybean


Visual symptoms appear during later growth stages, flowering and podding. The disease is characterized by a mottled purplish to brown discoloration of the upper leaves and their sunburned appearance. Red-brown spots may also appear on stems and pods. The infected seeds may look healthy or have pink to purple discolorations varying in size from spots to large patches on the seed coat.This may not have a negative impact on yields, but germination rates and seedling emergence may be affected.


Cercospora leaf spot is caused by Cercospora kukuchii. This fungus overwinters in plant debris in soils and on seeds. High relative humidities, warm temperatures (around 22 to 26°C), wind and splashes of rain favor the spreading of the fungus onto the leaves and the development of the disease. Initial infections are often latent and do not appear visible until flowering or pod formation stages. The fungus gradually enters the pod and grows on the seeds, giving them the characteristic mottled purplish or brown colour.

Biological Control

Sorry, we don't know of any alternative treatment against Cercospora kikuchii . Please get in touch with us in case you know of something that might help to fight this disease. Looking forward hearing from you.

Chemical Control

Always consider an integrated approach with preventive measures together with biological treatment if available. On lots with a high percentage of discolored seeds treat the seeds with fungicides. This may provide some control on the spreading of the disease. Consider applying foliar fungicides during early pod stages to prevent leaf blight and pod infections.

Preventive Measures

    Use certified pathogen-free seedsTolerant varieties are availableRotate with nonhosts to limit the incidenceTillage and exposure to solar radiation and wind reduce the survival of these fungi on plant residuesRemove plant debris after harvest and destroy them


Regional Weather

Get detailed forecast and actual weather data.

Plantix offers detailed weather information on the following issues:



Air Pressure


Wind speed

Plantix Community

Get in touch with experts around the world.

Post your questions

You can post your questions and pictures and get feedback from other farmers or gardeners. Plantix' experts will answer your questions related to plant diseases and pests.


Exchange with Plantix users around you, in your language and related to the crops you grow.

Global Community

Connect to farmers, gardeners, experts and interested people around the world that discuss plant diseases, remedies and best practice for sustainable farming.

AI-Driven Disease Detection

Instant diagnostics and solutions based on your picture

Image Recognition

Plantix analyzes your picture within a few seconds and gives you instant feedback on your plant problem.

Customized Management Options

On top of the detection result, Plantix offers you a detailed description of possible solutions - both biological and conventional.

Preventive measures

Plantix offers information on preventive measures to protect your crop from the next attack.