On Southern peas, sulfur or fixed copper can be used. When the disease is first noticed, sprays or dusts of sulfur are recommended for use on snap and green beans only. Do not use sulfur on young plants. Apply chemicals according to directions on the label. This fungal disease, caused by Cercospora species, occurs primarily on the lower leaves of plants as irregular, tan spots.
Severe infection causes excessive leaf drop and stunting of the plant.
Remove all debris in the garden after harvest. Do not plant beans in the same area for two to three years. There are no resistant varieties or recommended chemicals for this disease in the home garden. These spots enlarge rapidly under cool, moist conditions, and run together, girdling the stem. Infected pods turn into a soft, watery mass, before dying out and turning brown.