Dry celery is known as medicinal celery, celery, and parsley. An annual or biennial herb of the Umbelliferae family. Take the stem or root into the medicine, with the effect of reducing blood pressure, diuresis, cooling blood and stopping bleeding, which is widely cultivated throughout China. This article will introduce the pesticide control methods for celery blight, for your reference. Symptoms: Leaves, petioles, stems can be infected. The leaf is infected, one is the first disease of the old leaves, and then spread to the new leaves. The lesions on the leaves are scattered and vary in size. The diameter is 3-10 mm. The initial spots are light brown oily spots, which gradually enlarge. The middle part is brown and necrotic. The outer edge is mostly dark reddish brown and obvious. Black spots. The Other one is not easy to distinguish from the former. The center is yellowish white or grayish white. The edges are clustered with many black small spots. The lesions often have a yellow halo outside, and the lesions vary in diameter. The petiole or stem is infected, the lesion is brown, the oblong is slightly sunken, and the central part is scattered with black dots. At present, the disease has become an important disease of celery in winter and spring protection, which has a great impact on yield and quality. The pathogen celery is a fungus of the genus Aspergillus. The conidia are buried under the epidermal tissue, the size is 87-155.4×25-56 (μm), and the spore angle and spores are escaped from the orifice of the water. The spores are colorless and transparent, long linear, with a blunt tip and a septum. 0-7, mostly 3, size 35-55×2—3 (μm). When the conidia spores germinated, the membrane increased or broke into several sections, and the growth was good, and the developmental temperature was 20-27 °C, and the growth and development was slower than 27 °C. Only attack celery. The route of transmission and the pathogenesis of the disease mainly depend on the wintering of the seedlings in the seed coat or the diseased body, and survive for more than one year. The seeds are sown, and the disease is infected after emergence, and the conidia are produced and spread in the nursery. The pathogens that overwinter on the diseased body, in the condition of suitable temperature and humidity, produce conidia and conidia, and spores are transferred to the celery by wind or rain splash. The spores sprouted to produce germ tubes, which were invaded by stomata or penetrating the epidermis. After 8 days of incubation, the diseased part produced conidia for reinfection. The disease is prone to occur under cold and high humidity conditions, the temperature is 20-25 ° C, and the incidence is heavy when the humidity is high. In addition, even rainy or dry during the day, fog or dew at night and too high temperature, plant resistance is weak on the incidence. Control method (1) Select resistant varieties. Such as Jinnan real parsley, winter parsley, Xia Qin, Jin Qin, Tianma, Shanghai Daqin, Ventura, American glass crisp, Celery No. 3, Chunfeng and so on. (2) Select disease-free seeds or disinfect the diseased seeds. Seeds are collected from disease-free plants or stored for 2 years. If new seeds are used, they should be soaked in warm soup, that is, immersed in warm water at 48-49 °C for 30 minutes, stirred while dip, then transferred to cold water for cooling, dried and then sown. (3) Strengthen field management, apply enough base fertilizer, look at seedlings and topdress, and enhance plant disease resistance. (4) Protected cultivation should pay attention to cooling and dehumidification. During the day, the temperature should be controlled at 15-30 °C. If it is higher than 20 °C, it should be released in time. At night, it should be controlled at 10-15 °C to reduce the temperature difference between day and night, reduce condensation, and avoid flooding. (5) When the celery seedlings are protected by 3cm, the 45% chlorothalonil fuming agent should be applied. The dosage: 200-250g per 667m2, or 5% chlorothalonil dust, lkg per 667m2 . The open field can be sprayed with 75% chlorothalonil wettable powder 600 times liquid or 53.8% to kill 2000 dry suspension agent 1200 times liquid, 64% antivirus hydrazine powder 500 times liquid, 40% more. Sulfur suspension 500 times solution, 12% green milk copper emulsion 500 times solution, 47% Jiaruinong wettable powder 500 times solution, once every 7-10 days, continuous prevention and control 2-3 times. kaiping aida sanitary ware technology co.,ltd , https://www.kpaidafaucets-jm.com