Powdery mildew is a common fungal disease affecting many plants, including chili and peppers. The disease is caused by various fungi species forming a white powdery coating on infected plants’ leaves, stems, and flowers. This coating reduces the plant’s ability to photosynthesize, causing stunted growth and reduced yield.Chili is one of the most important vegetable crops globally. It is used extensively in various cuisines for its unique flavor and health benefits.
A combination of cultural, biological, and chemical controls is necessary for managing powdery mildew in chili. Planting resistant cultivars, keeping the appropriate spacing between plants, and avoiding overhead irrigation are all examples of cultural control practices. The use of beneficial microorganisms that compete with the pathogen for resources is at the heart of biological management. To prevent the development of resistant strains, fungicides, which are used in chemical control methods, must be used carefully.
Powdery Mildew Management in Chilli Pepper
Causes/Pathogen of Powdery Mildew in Chilli
Powdery mildew in chili is caused by a fungus called Leveillula taurica. The fungus survives in leaf buds and other plant debris during winter and is spread by wind, water, and insects to nearby plants. Unlike most fungi, powdery mildew can thrive in dry conditions.
The Disease Cycle of Powdery Mildew in Chilli
The powdery mildew disease cycle in chili starts with the landing of spores, called conidia, on a chili leaf. These spores germinate and grow into the leaf, using the plant as a food source. The fungus remains unseen within the leaf for an 18-21 day latency period. Then, it grows out of the breathing pores on the leaf’s underside, producing spores singly on numerous fine strands or stalks called conidiophores.
These fungal strands become visible as white patches or mildew colonies on the underside of the leaf. Repeated powdery mildew cycles can lead to severe outbreaks that economically damage the crop. This disease cycle continues as the spores are transmitted by wind, water, or insects to nearby plants, continuing the cycle of parasitization and spreading.
Conditions Favorable for Powdery Mildew Spread in the Field
Powdery mildew thrives at around 30°C, although it can survive in temperatures between 10-12°C. Unlike downy mildew, powdery mildew is spread by small amounts of rainfall and regular morning dew, accelerating its growth and spread in the field.
Damage Symptoms of Powdery Mildew
Leaves with powdery mildew have a white powdery covering on their undersides. Yellow patches may also be seen on the upper surface. Severe infections lead to the drying and shedding of affected leaves. Powdery growth may also be observed on branches and young fruits, causing the premature dropping of diseased fruits that do not grow further.
Yield Loss due to Powdery Mildew on Chilli
Powdery mildew caused by Leveillula tauri