Carrot leaf blotch, also known as leaf spot disease. The carrots cultivated in the open field in the autumn usually begin to develop in the early winter. If the control is not timely, it is easy to spread rapidly. When the disease is severe, the leaves of the field are yellow and fire-like, which can cause a significant reduction in carrot production. The following describes the pathogenesis of carrot leaf spot disease and control methods. The lesions on the main symptoms of diseased leaves are irregular or near-circular, and the boundaries between diseased and healthy tissues are clear. The lesions are yellowish-green on the edge, brown or dark brown on the center, dense black particles on the lesions, and small particles buried or semi-buried. On the petiole, a blackish-brown, irregularly shaped lesion with slight sag was formed. Small black particles were scattered on the lesion. When the onset was severe, the leaves were covered with lesions or lesions, resulting in premature yellowing of the leaves. Characteristics of the disease The pathogens of the disease are scattered over the surface and in the soil as the diseased bodies are scattered over the winter, and the seeds can also be carriers of bacteria, which are the primary sources of infestation. The pathogenic conidia of the pathogenic fungus spewed out of the conidia after being absorbed by water and spread through wind and rain and irrigation water, and penetrated through the stomata or penetrating the epidermis. The disease re-infested frequently and the disease developed rapidly. The bacteria is warm and wet. Especially with extensive management, the incidence of declining growth is the heaviest. In the early stage of disease prevention and treatment, 70% of mancozeb WP can be used for every 666.7 square meters, 500 times of 80% of new Wansheng WP, 40% of Dafentan WP, or 40% of WP. 500 times of polysulfide suspending agent, or 77% can kill 800 times of wettable microparticle powder, or 50 to 60 kilograms of 1:1:160-200 Bordeaux mixture, spray every 7 to 10 days, and even spray 2 ~ 3 times. Poly-Lok Ligating Clips,Weck Hemoclip Applier,Ligating Clips Use,Polymer Ligation Clips Qingdao DMD Medical Technology Co., LTD , https://www.conston-tech.com