Bacterial spot (Xanthomonas campestris pv. vesicatoria)
Leaves, fruit and stems can be attacked by the disease. Leaf spots begin as circular, water-soaked that become necrotic with brown centres surrounded by yellowish borders. The spots are sunken on the upper leaf surface and slightly raised on the lower surface. On stems spots are elongated. Affected leaves turn yellow and drop. Affected fruits have raised brown spots that are wart-like in appearance. The disease has a wide distribution wherever peppers are grown. It spreads rapidly during warm, rainy conditions. High relative humidity with free moisture on leaves for long periods favours infection. Ideal temperatures for infection are above 20°C . The bacterium is seed-borne and survives in crop debris.
- Use of resistant varieties, if available.
- Use certified disease-free seed.
- Crop rotation.
- Copper sprays can reduce the rate of disease development.