How to prevent and control pepper powdery mildew? These measures need to be mastered

Pepper powdery mildew is a fungal disease caused by powdery mildew fungi. This disease has become one of the serious diseases of peppers, severely harming the yield and quality of peppers. Below, the editor brings you the symptoms, occurrence patterns, and prevention and control methods of powdery mildew. Let's take a look.

1. Disease symptoms

Powdery mildew mainly harms the leaf parts of peppers, and also harms tender stems and fruits. When leaves are affected, chlorotic spots of varying numbers and irregular shapes appear, and a sparse mold layer appears on the back of the leaves. The chlorotic spots begin to continuously spread, causing large-area chlorosis of the leaves. This disease hinders leaf photosynthesis and affects the normal growth of the plant. In severe cases, the leaves wither and necrose.

2. Occurrence patterns

The powdery mildew pathogen is an endoparasitic fungus. After the disease occurs in the field, the hyphae continuously spread within the mesophyll tissue, and conidia extend from the stomata on the back of the leaves and disperse under dry conditions. It mainly spreads through spores carried by airflow, continuously invading new leaves, and then produces new spores at the diseased sites. After the spores mature, they fall off and spread by wind, repeating this cycle, causing the entire field to become infected in a short time. In the early stage, powdery mildew conidia are mainly parasitic as internal hyphae. Generally, when disease spots are found on leaves, it is already the late stage of the disease, which brings certain difficulties to prevention and control.

3. Agricultural control

Strengthen fertilizer and water management in the field. Before planting, apply decomposed organic fertilizer or farmyard manure as base fertilizer, which can prevent pathogens and insect eggs from being brought into the field. During the plant growth period, increase the application of phosphorus and potassium fertilizers, apply less or no quick-acting nitrogen fertilizer, plant at a reasonable density, irrigate appropriately, ventilate frequently, pay attention to the soil moisture content, and avoid alternating dryness and wetness. When watering, try to choose sunny mornings, and drip irrigation is preferable. Remember not to use flood irrigation or irrigation outside the film. Watering is generally done once every 10-20 days, and the watering interval varies in different seasons.

4. Chemical control

In the early stage of the disease, when there are only a few chlorotic disease spots on the leaves, the pathogenic hyphae are still in the germination stage within the leaf tissue. At this time, promptly spray agents such as triadimefon, ningnanmycin, and wuyiencin, once every 7-10 days, for 2-3 consecutive sprays, which can effectively control the disease. In the middle stage of the disease, when white disease spots appear on the plant leaves, tender stems, and fruits, the pathogenic bacteria have already developed externally and will begin to spread under suitable environments. At this time, the control agents should be increased by 15%-20%, and spraying must be comprehensive. Control agents can include flusilazole emulsifiable concentrate, kresoxim-methyl water-dispersible granules, pyraclostrobin emulsifiable concentrate, etc.

The above is an introduction to the prevention and control measures for pepper powdery mildew. I hope it can help you. For more related knowledge, please stay tuned to us.