Green bean leaf spot disease control notice

Mung bean leaf spot is a serious disease harmful to mung bean, which can dry up mung bean leaves, decrease quality and reduce yield. the following is to introduce the symptoms, ways of transmission, conditions and control methods of mung bean leaf spot disease. The symptom of mung bean leaf spot is mainly harmful to mung bean, and the damage site is the leaf. Mung beans suffer heavily during the flowering and podding stage. In the early stage of the disease, there were water-stained brown spots on the leaves, which expanded to form reddish brown to reddish brown on the edge and light gray to light brown in the middle. When the humidity is high, there is a dense gray mold layer on the disease spot, that is, the conidiophores and conidia of the pathogen. When the condition is serious, the disease spot fuses into a piece and soon dries up. The light ones reduced production by 20% to 50%, and the serious ones by as much as 90%. The route of transmission is that mycelia and conidia overwinter in seeds or diseased bodies, becoming the source of infection at the beginning of the next year. The growing season is harmful to the leaves, which expands rapidly before and after flowering and spreads by wind and rain. Under the hot and humid conditions, the pathogens accumulated many times after the conidia were re-infected, and became prevalent when there were suitable conditions. High temperature and humidity are beneficial to the occurrence and prevalence of the disease, especially in rainy autumn, continuous cropping or out-of-season cultivation. Control methods 1. Select varieties resistant to leaf spot disease, such as Qindou 4, Qindou 6, Zhonglu 1, Luyin 1 and so on. The disease-free plants were selected and disinfected by soaking the seeds in 45 ℃ warm water for 10 minutes before sowing. 2. Deep ploughing should be carried out after harvest, and rotation should be carried out if possible. 3. Spraying 50% carbendazim (carbendazim plus ethamyl) wettable powder 1000-1500 times or 75% chlorothalonil 600 times, 12% green copper EC 600 times, 80% Dasheng M-45 wettable powder 600 times, 47% Carrinone wettable powder 1000 times, 50% mixed sulfur suspensions 500-600 times, 30% alkaline copper sulfate suspensions 400 times, 1ther 1ther 200 times Bordeaux. Once every 7-10 days, prevention and treatment for 2-3 times.