I. Symptoms: At the beginning of the disease, there are small spots of watery yellowish yellow spots on the leaves. After the lesions are enlarged, they are limited to form a polygonal yellowish-brown to brown spot. When the humidity is high, the gray and black moldy layer grows on the back of leaves. In severe cases, the lesions are contiguous and the whole leaf is yellow. II. Control methods: 1. The varieties resistant to downy mildew of resistant varieties include Jinchun No. 5, Jinlu No. 2 and Jinyou No. 30. 2, cultivation of disease-free seedlings to improve cultivation techniques, nursery greenhouse and production greenhouses separate, reduce seedling infection. 3. Strengthen field management Strengthen ventilation and reduce humidity, increase phosphorus and potassium fertilizers, and increase plant disease resistance. 4. In the early stage of the disease prevention and control, spray 72.2% Preclosure 800 times, or 75% chlorothalonil wettable powder 600 times, or 25% Rhodoxypora WP 750 times, or 72% grams. 800 times exposed fluid. Body Care,Antibacterial Body Wash,Natural Skin Care,Organic Skin Care Guangzhou Lingxue Cosmetics Co., Ltd , https://www.gzlxgj188.com