Early preparation for disease prevention of autumn Chinese cabbage

Before and after the Beginning of Autumn, Chinese cabbage was sown in North China, but soft rot, dry heartburn, downy mildew, black spot and other diseases affect the yield and quality of Chinese cabbage every year, which is a major heart disease for farmers. Most farmers spray medicine only when they find diseased plants, but the results are often not ideal. One dose of medicine can last up to a week at most, otherwise the disease will continue. In this way, in a growing season, farmers should spray medicine once a week, at least three times, which is time-consuming and costly, resulting in high drug residues. In fact, comprehensive prevention and control is the best control plan. Select varieties with good resistance and good quality, try to choose cannon-type Chinese cabbage varieties with strong disease resistance and good quality, represented by Beijing Xin No. 3. Chinese cabbage cultivated by plot selection and ridging is not tolerant to drought or waterlogging, and the high humidity environment is very beneficial to the occurrence of soft rot, downy mildew and black spot. The land with sandy loam and convenient drainage and watering should be selected as far as possible, and ridging cultivation can obviously reduce the occurrence of diseases. Balanced fertilization is very important. Chinese cabbage likes both nitrogen and potassium. About 100 jin of potassium sulfate type nitrogen, phosphorus and potassium compound fertilizer per mu was applied as base fertilizer, and high quality potassium nitrate was applied at rosette stage to supplement nitrogen and increase potassium, as well as 30 jin of urea and 20 jin of potassium sulfate per mu. Apply as much organic fertilizer as possible, but it must be fully mature organic fertilizer. Timely sowing wrong development disease date properly postpone the sowing date and avoid the period of high temperature and humidity in the rosette stage, which can obviously reduce the occurrence of the disease. Early-maturing varieties can be postponed by about a week after the Beginning of Autumn, medium-maturing varieties can be postponed to three days after the Beginning of Autumn, and late-maturing varieties the Beginning of Autumn can be sown on the same day. Seed treatment to reduce the amount of bacteria before sowing, mix seeds with 3% Zhongshengmycin wettable powder according to 1% of seed weight, or more than 40% bromine wettable powder, mix seeds according to 0.3% of seed weight. Spraying in advance to prevent diseases Chinese cabbage seedlings were sprayed three times in a row, once every 7 days or so. Agricultural streptomycin, Zhongshengnin, 30% copper succinate suspension and other agents can be selected to prevent bacterial diseases such as soft rot and black rot. When the diseased plant is found to have soft rot disease after spraying and pulling out the diseased plant, the diseased plant is first removed and taken out of the field for deep burial, and immediately sprayed for treatment. 72% frost urea manganese zinc wettable powder and enyl morpholine can be selected for downy mildew, difenoconazole, nitrile and other fungal diseases such as black spot and anthracnose can be selected, and for dry heartburn, foliar fertilizer containing calcium and zinc-iron-boron multi-element fertilizer should be sprayed twice.