Prevention of cabbage black rot
Cabbage black rot is an important disease that damages cabbage, and it can be attacked from the seedling stage to the bulbous stage. After harming the leaves and flower bulbs, the curd loses its commercial value, resulting in a reduction in yield and serious damage to the vegetable farmers. Therefore, it is imperative to prevent cabbage black rot in a timely manner so that early cure, minor cure and cure can be achieved. 1, symptom recognition. Cabbage black rot mainly damages leaves, leaves or bulbs. At the seedling stage, the cotyledons were immersed in water and quickly died or spread to true leaves. At the time of onset, the first step was to start from the leaf margin, and a "V"-shaped yellow-brown band appeared at the tip of the leaf marginal vein. If 5-10 true leaves at the time of onset, the lowest leaf begins to wilt and turn yellow, and then the whole plant gradually withered; if it occurs in the rosette period, cabbage balls appear black spots, the ball is loose and loose, and it completely loses the value of the goods. . Once the disease occurs, the area of ​​infection is larger and the incidence is faster, which will result in serious reduction of production. 2, the law of occurrence. The pathogenic bacteria on the seed or with the diseased body in the winter in the soil, from the leaves of the seedlings or leaves of the true leaves, water holes or wounds invasion, and quickly into the vascular tube caused by the base of the disease. Germs can spread through farm tools and rainwater. High temperature and high humidity, repeated cropping, and unbalanced soil microbial environment are conducive to the survival and reproduction of pathogens. 3, control methods (1) Agricultural control. Soaking in warm water at 50°C for 20-30 minutes or soaking in 0.1% copper sulfate solution for 156 minutes. Severely affected plots and cruciferous vegetables have a 2-3 year rotation. Improve soil supply and drainage conditions, increase organic fertilizer, phosphorus and potassium fertilizers and trace fertilizers. (2) Chemical control. The seedbed was sterilized by spraying the soil with 50% dexsenimine 800-1000 times, or 50% carbendazim 800 times. At the beginning of the disease, use 14% solution of ammonia-copper water bath agent 600 times, or 77% copper hydroxide wettable powder 500 times, or 72% agricultural streptomycin soluble powder 500 times, once every 7-10 days, even spray 2 -3 times. Office Safe,Office Digital Safe,Security Office Safe,Electric Key Safe Box Ningbo Reliance Security Technology CO.,Ltd , https://www.reliancesafes.com