The farmers in Yongnian County recently called to inquire about how to prevent spot blight of celery. Celery is one of the main varieties cultivated in the winter and spring protected fields. Spot blight of celery is the most serious disease in the protected area, which seriously affects the yield and quality of the celery. Generally, it can reduce production by 3% to 4%, and serious can reduce production. 6 %the above. The spotting of celery is also known as late blight and dead leaf disease, commonly known as "fire dragons." The celery leaf blotch usually occurs on the leaves first. The light brown oil-like spots appear on the leaf surface firstly. The outer edges of the lesions are tan and brown, and the middle yellow-white to gray-white. Afterwards, they develop into irregular patches. There are many small black spots on the lesions, which are the conidiospores of pathogenic bacteria. It is one of the important features to identify the disease. Spot blotch is a common disease on protected celery. As winter temperatures gradually decrease, The low-temperature and high-humidity environmental conditions in protected areas are conducive to the occurrence and epidemic of the disease and should be promptly prevented and controlled. The leaf blight of celery mainly damages the leaves, followed by the petiole and stem. The old leaf first onset, the lesion was light brown oil-like spots, the edge is obvious, the disease is a fungal disease, the optimum temperature is 20-25 °C, suitable humidity is more than 95%, the incidence of protective celery is heavier. Even cloudy days, frequent temperature fluctuations or hot during the day, dew condensation at night, weak plant growth, excessive irrigation, lack of timely ventilation, and the like can easily lead to rapid disease spread. Prevention and control of celery spot blight, should take comprehensive measures, chemical control, celery spot blight should be the main prevention, when the seedling height 2-3 cm, should be timely spraying 75% chlorothalonil wet powder and other targeted pharmaceuticals to prevent, and With the spraying of new high-fat membrane 800 times liquid to enhance efficacy, improve the utilization of effective pharmaceutical ingredients, consolidate the control effect. (1) Seed disinfection. The lethal temperature of celery leaf spot blight is about 49°C. Soaking seeds with hot water for 30 minutes before sowing may kill some germs. When soaking, it must be stirred continuously. (2) Balanced fertilization. The fully-fertilized organic manure was applied in the base plant. Phosphorus and potassium fertilizers were applied at the growth stage to control the amount of nitrogen fertilizer, and foliar fertilizer and micro-fertilizer were sprayed in time to enhance the plant's resistance to stress. (3) Cooling and dehumidification. Daytime temperature control in the 15-20 °C, more than 20 °C timely ventilation, night control at 10-15 °C, reducing the temperature difference between day and night, reducing condensation. Can not flood irrigation. (4) Remove the diseased body in the protected area in time to reduce the bacteria source. (5) Chemical control. The spraying of celery seedlings began at 3 cm height, 70% Mancozeb WP, 58% Metalaxyl Manganese Zinc Wettable Powder, 64% Methoracic Manganese Zinc Wettable Powder, 75% Bacterial WP, 50% carbendazim WP, etc., once every 7-10 days, continuous control 2-3 times. Early onset of disease prevention and control, try to avoid spray spraying, you can use 45% chlorothalonil smoke agent 200-250 grams per acre smoke, or per acre with 5% chlorothalonil powder 1000 grams to reduce the shed humidity. Warm Coat,Mens Sport Coat,Polyester Warm Coat,Polyester Fibre Coat Xinhui Jielide Garment Factory , https://www.ntgfwear.com