Control techniques of anthracnose in Capsicum

Anthracnose is a common disease in spicy (sweet) pepper, which is distributed all over the world. Can cause pepper leaves, rotten fruit, seedling death. Generally speaking, the harm is not serious, but in rainy years, the disease is serious. According to its symptoms, it can be divided into black anthrax, black spot anthracnose and red anthrax.

Black anthracnose occurs in Northeast, North China, East China, South China, Southwest and other regions. The general diseased fruit rate is about 5%. In severe cases, the diseased fruit rate reaches 20% to 30%, which has a certain impact on the quality and yield of hot pepper. Black spot anthracnose only occurs in Zhejiang, Jiangsu, Guizhou and other places. Red anthrax is less common.

The disease not only harms pepper, but also infects eggplant and tomato. The main harm to the fruit, especially the near-mature fruit is more likely to occur, but also infect leaves and fruit stalks. Fruit disease, the initial spot is water-stained, brown, oblong or irregular, enlarged spot sunken, spot raised irregular ring, the ring on the dense black or orange small spots (conidia disc). When it is wet, there is a moist discoloration ring around the disease spot, and when it is dry, the disease spot often shrinks and easily breaks. Leaf disease, the primary faded green water stains, enlarged into brown, round, gray in the middle, and in the later stage there are small black spots arranged in wheel on the disease spot. Stems and pedicels are sometimes killed, forming brown sunken spots, irregular, and easy to crack when dry. There is also a diseased fruit in the field, the symptoms are similar to the above, but the black grains produced on the spot are large and dark, which is often called black spot anthracnose.

Control measures of anthracnose in capsicum

1. Select disease-resistant varieties: disease-resistant varieties can be selected according to specific conditions, and generally spicy varieties are more resistant, such as Hangzhou chicken claw pepper, sweet pepper varieties, such as Changfeng, eggplant pepper No. 1, Tiepiqing and so on.

2. Select disease-free seeds and seed disinfection: establish disease-free seeds or seeds from disease-free fruits. If the seeds are infected, soak the seeds with 55 ℃ warm water 10min or 50 ℃ warm water 30min before sowing. After taking out, cool with cold water, accelerate germination and sow seeds. You can also soak the seeds in cold water for 10 hours, then soak 5min with 1% copper sulfate solution, and then neutralize the acid with a small amount of plant ash or quicklime before sowing.

3. Crop rotation and strengthening cultivation management: the seriously affected plots should be rotated with Solanaceae and Leguminosae vegetables for more than 2-3 years. We should apply nitrogen, phosphorus and potassium fertilizer on the basis of sufficient organic fertilizer, avoid planting in overdense and low-lying land, raise seedlings in nutrition bowl, cultivate healthy seedlings of appropriate age, prevent fruit sunburn, remove disease residues in the field and reduce the source of bacterial infection.

4. Chemical control: spraying at the initial stage of the disease or fruit coloring, the effective agents are: 50% Baogong, 80% Dasheng mmur45, 75% Dakening, 65% Dysen zinc, 80% Punol, 60% Tuofu, 70% thiophanate methyl, 80% anthrax Fumei, Bordeaux solution (0.5 Freund 100), 50% carbendazim, etc., once every 7 days and 3 times in a row.