Pepper Diseases


Stem Rot (Southern Blight)
Sclerrotium rolfsii

Worldwide in warm to tropical climates

Damage Symptoms

The disease occurs as a sudden wilt of individual plants. Scattered about the field. Initially there is no foliar discoloration, but later the leaves may turn yellow. The cortical tissue at the base of the stem is brown and decayed above and below the soil line. White mycelial growth usually is visible on the base of the stem and on the soil around the base of the plant, creating a collar rot. Brownish sclerotia about the size of mustard seed are produced in the mycelial mat. Fruit or branches may become infected at the point of soil contact.

Conditions for Development

The disease has a wide geographic distribution in warm climates. High soil moisture and temperature favor disease development, although symptom expression may be more severe during dry conditions following a wet period. The fungus has an extremely broad host range and is a good saprophyte. Sclerotia are its principal means of long-term survival in the absence of a host or suitable substrate.

Control

Allow ample time for breakdown of green manure or plant debris before planting the crop. Plow deeply to bury sclerotia and plant debris. Soil fungicides or fumigants are beneficial in areas where the disease is severe.