Southern blight is a fungal disease that attacks the base of a plant and can move quickly when conditions are hot, humid, and poorly ventilated.
Growers should watch for white fungal growth, small sclerotia, sudden collapse, and problems around the root crown. Prevention depends on airflow, drainage, sanitation, and avoiding long periods of wet soil.
Once symptoms appear, isolate the plant, remove affected material when possible, and treat the surrounding growing area carefully so the problem does not spread.