Sclerotinia cucumerinum is an important disease in cultivated cucumber. Greenhouses and greenhouses occur from autumn to spring in the following year, with serious diseases in some areas and large yield losses. The disease also affects cabbage, cabbage, radish, tomatoes, peppers, beans, and other vegetable crops. The symptoms of damage mainly damage the fruits, stems and leaves, but cucumbers can be affected at each growth stage. The incidence of plants was mostly at the base of stems, and water-spotted lesions appeared. Gradually, the diseased stems became light brown and soft rot, resulting in white cotton flocculent mycelia and black sclerotia. The epidermis was longitudinally divided and the plants were dry. Most of the fruit occurs from the top of the stump, spreading into water spots, and finally the whole melon is rot or rot. Control methods strictly control the introduction of diseased seedlings: newly opened greenhouses, greenhouses and protected areas without disease, to ensure the disease-free seedlings transplanted, do not have diseased greenhouses and greenhouse nursery. Seed treatment: The sclerotia were floated with 10% saline and eliminated. Seeds were soaked in warm water at 50° C. for 10 minutes. The seeds were germinated after cooling with clear water. Strengthen cultivation and management: The soil should be turned over 15 cm deep to prevent sporangial discs from unearthing and flood irrigation should be avoided to control the soil temperature and humidity. The air is released in a timely manner to reduce the humidity of the air. The average temperature of the greenhouse in the early spring is controlled at 29°C to 31°C, and the relative humidity does not exceed 65%. If the soil moisture content is too large, the irrigation interval may be appropriately extended. The diseased melons and diseased leaves are removed in time and cleared out of the ground or incinerated to prevent the spread of the disease. Chemical control: Spray 50% Suo Ke Ling wettable powder 1500 to 2000 times liquid, or 50% Propionine wettable powder 1000 times, or 20% Membrane Liquor 1000 times, or 50% agri Ling wettable powder 1000 times, or 40% seedling net wettable powder 1000 to 1500 times, or 50% carbendazim wettable powder 500 times. Sprayed once every 7 days during flowering period, spraying 3 to 4 times. The protected area can be sprayed with 5% chlorothalonil dust at 1 kg/mu, or 45% chlorothalonil aerosol and 10% quick-drying aerosol for smoking in the evening-sealing greenhouse. 250 g/mu .