In recent years, black rot of cauliflower has been increasing year by year, which has seriously affected the yield and quality of cauliflower. The disease is a bacterial disease caused by Xanthomonas species. Besides harming broccoli, it also harms many kinds of cruciferous vegetables such as cabbage, cabbage, rape, mustard and radish. Heavy crops, frequent rainfall, partial application of nitrogenous fertilizers, and heavy pests cause severe disease. Symptoms Cauliflower seedlings were victimized and the cotyledons were immersed in water and gradually browned, withered, and spread to true leaves. The veins showed small strips of varying lengths. The onset was heavy during the mature period, which mainly harmed the leaves and expanded from the leaf margin inwards, forming a "V"-shaped yellow-brown lesion. The posterior leaf veins became necrotic and black, and the leaf margin appeared black rot. Yellow halos were formed on the edges of the lesions and the stems were Diffusion of the roots and roots causes the vascular bundles of the stems and roots to become black, and the flower balls appear as gray and black dry rot. In severe cases, the plants die. Prevention (1) Seed disinfection. The disease-free seeds were selected and soaked for 15 minutes with 200-fold solution of 50% Daisen ammonium hydroxide solution, washed and dried and sowed. (2) Seedbed disinfection. For each square meter of seedbed, mix 40% of Formamide WP and 8 to 10 grams of WP with appropriate amount of dry fine soil, one third of which is sprinkled on the surface and two-thirds of it is used to cover seeds. (3) The rotation is changed. Severe disease fields can be used for 2 to 3 years of rotation with non-cruciferous crops to reduce field sources. Before planting, deep soak the sun for 10 to 20 days to kill the bacteria in the soil. (4) Control pests. In addition to direct damage caused by pests, but also caused by wounds, is conducive to the invasion of bacteria, so pests and more fields of black rot also occur, to prevent disease must first pests, such as diamondback moth, cabbage caterpillar, beet armyworm, aphids, cockroaches Ye Jia, mantle and so on. (5) Strengthen management. Timely sowing, moderate seedlings; timely drainage after rain, to prevent excessive soil moisture; irrigation when flooding can not be flooded; reasonable fertilization, promote plant growth and robustness, and improve disease resistance. (6) Clean the countryside. After harvesting cauliflower, the stubble roots and leaves were promptly removed and taken out of the field and buried or burned. (7) Chemical control. After the occurrence of black rot disease in the field should be timely prevention and control, can choose to use 14% ammonia solution, can kill 77% copper hydroxide wettable powder, 50% agent ammonium water agent, 72% agricultural streptomycin sulfate Soluble powder and other drugs plus water spray, once every 7 to 10 days, continuous control of 2 or 3 times, severe disease field can increase the frequency of application according to the condition. Green Sencha,Sencha Powder,Sencha Tea Leaves,Private Label Sencha SHAOXING ROYAL TEA VILLAGE CO.,LTD , https://www.yccmatcha.com