How to control potato late blight?

What are the hazards of potato late blight? Is there any way to prevent it? Also ask netizens to help guide the farming network to sort out the harm and control methods of potato late blight, which are listed below for netizens' reference. The harm of potato late blight: the late blight spreads quickly, the damaged stems and leaves rot and die quickly, and most of them occur after flowering; potato leaves, stems and tubers can all be damaged by late blight. At the initial stage of the disease, the leaf disease spots began to occur at the leaf tip or leaf edge. It expands rapidly when it is wet, it is rotten and black, and the edge of the spot is not clear. Emitting a special smell of decay, the edge of the leaf produces a circle of white mildew, and there is dense white mold on the back of the leaf, forming a mildew wheel. When the weather is dry, the disease spot is dry and brown, and there is no white mold on the back of the leaf. The field has high humidity, dew in the morning and evening, often overcast and rain, the temperature is not less than 10 ℃, and the late blight is serious. Prevention and control of potato late blight: after the central diseased plant was found in the field before and after flowering, the potato was deeply buried and sprayed with insecticides. 100 g / mu of Kelu can be evenly sprayed in the whole field for preventive and protective control. The interval of spraying with 40 g / mu of Yikuanjing is 5-10 days. Under normal weather conditions, medication is used at intervals of 7 to 10 days, 25% metalaxyl wettable powder 800 times, or 65% Dysen zinc wettable powder 500 times, 64% alum wettable powder 500 times, 40% aluminum ethyl phosphate wettable powder 500 times, 75% chlorothalonil wettable powder 600-800 times. Spray once every 7-10 days, 2-3 times continuously. If there is little rain and drought, the interval of spraying can be extended appropriately. Medication should be used at intervals of 5 to 7 days under high wet and rainy conditions. The frequency of medication can be adjusted appropriately according to the risk of the disease. Click to get more potato planting techniques click to get more vegetable planting techniques