Rhizoctonia Root Rot

(click image to enlarge) Symptoms:
• Can be observed at crown or below soil line
• Circular to oval, dark lesions merging together over time
• Cracking
• Rot progresses inward with sharp defined margin between healthy and diseased tissue
• Decay of the root is enhanced by secondary fungi and bacteria

Epidemiology:
• Grows between 54-95° F
• Optimum temperatures 68-91° F
• Does not require high soil moisture
• Severe in heavy, poorly drained soils or wet areas

Control:
• Tolerant varieties
• Crop rotation without dry beans, corn, or weeds
• Fungicide applications at planting and when soil temperatures become favorable
• Irrigation management