How to prevent and cure cabbage virus disease in summer?

How to prevent and cure cabbage virus disease in summer? Please give guidance on the prevention and treatment of summer Chinese cabbage virus disease. In general, the heart leaves are yellowed and wrinkled at the seedling stage, the heart leaves cannot be wrapped into balls, the leaves at the adult stage are brittle, shrinking, the core is not solid, and grayish-brown patches are formed on the leaves, affecting yield and marketability. High temperature and drought, especially the weak growth of vegetable plants under the condition of high night temperature, is an important external condition of infection. Watering frequently, do not squat seedlings adhere to the principle of three-water seedlings, five-water seedlings, and then water every 2-3 days, one to the end, watering time in the evening is the best. To control nitrogen and increase phosphorus and potassium and promote the growth of strong seedlings, it is appropriate to apply 5 kg biological potash fertilizer, 50 kg potassium sulfate compound fertilizer and 15 kg ammonium bicarbonate per mu. Timely control of aphids, elimination of toxic sources and immediate spray control of aphids. Adding 0.3% potassium dihydrogen phosphate during spraying can improve the efficacy and enhance the disease resistance of vegetable plants. When it is found that the diseased strains in the center should be removed immediately to prevent infection, and spray 500 times of virus A500 times or 500 times of Zhanling 800 times for prevention and control. Click to get more cabbage planting techniques click to get more vegetable planting techniques