Several important diseases can occur during the pepper growing season, from planting to harvest. The most significant disease is pepper blight.
Pepper Blight (lat. Phytophthora capsici)
The first symptoms of the disease appear in the root collar area. The root becomes dark black, followed by necrosis and wet rot. Affected plants wilt and dry out quickly. The damage is greatest after heavy irrigation, as water is necessary for the fungus to develop. The fruits can be attacked directly or through the stem. If a dry period follows the infection, the fruits shrivel, and in wet conditions, a watery spot appears on the fruits, covering the entire fruit, and white mycelium develops on it. Symptoms on the leaves manifest as necrotic spots, which, in the presence of high humidity, can be covered with white mycelium. The fungus overwinters in infected plant debris or soil without a host plant and requires high temperatures up to 35°C. Water is necessary for the infection to occur.
White Rot (lat. Sclerotinia sclerotiorum)
Peppers are susceptible to this fungal disease. Symptoms are most often found on the stem at ground level, where an elongated watery spot gradually spreads, encompassing the stem. The leaves above the affected area lose their firmness and dry out. The affected parts are covered with snow-white fluffy mycelium. Fruits can also be infected. The fungus can survive in the soil for many years. It prefers light, airy soils where water does not accumulate (excess water in the soil increases CO2 levels, and in such soils, white rot develops poorly).
It is important to implement preventive measures to reduce the incidence of this parasite.
Preventive measures include:
- Crop rotation
- Soil tillage with plowing, which buries the fungus deeper into the soil where conditions are not conducive to the development of fruiting bodies
- Infected plants should be removed from the plantation and burned before the sclerotia (the form in which the fungus overwinters) develop
- Soil sterilization (thermal or chemical)
Other diseases that can be problematic in pepper cultivation include: concentric leaf spot (lat. Alternaria spp.), powdery mildew (lat. Leveillula taurica), and verticillium wilt (lat. Verticillium dahliae).
