How to control potato late blight in winter?

What are the hazards of potato late blight? How to control potato late blight in winter? Are there any netizens who know about it to help introduce the harm and control methods of potato late blight through the farming network? The following is listed for netizens' reference. Harm of potato late blight: potato leaves appear water-immersed disease spots, which will be necrotic within a few days, turn brown when dry and turn black when wet. Under dark and humid conditions, mildew-like sporangium can be seen on the back of potato leaves, usually forming a yellowish greenish edge around the spot, which is black or brown on the stem or petiole. The disease spot on the potato stem is very fragile, and the stem is often broken from the spot. Under some conditions, the stem with disease spot may wilt, which will affect the growth of potato, and the yield will be low and the harvest will be lost. Prevention and control methods of potato late blight in winter: method 1. Potato late blight is mainly carried by seed potato. Seed soaking has a certain delaying effect on the occurrence of late blight, but it can not control the occurrence of the disease. Field growth period chemical spray to control the occurrence of late blight has a good effect. Method 2. Immediately after the potato plants with late blight appeared in the early flowering stage, 25% metalaxyl WP500 solution and other agents were sprayed to control the late blight. Metalaxyl has the best control effect on late blight. Secondly, Lemicol, metalaxyl manganese zinc and metalaxyl copper all have certain control effects. It is suggested that metalaxyl should be used to control potato late blight in a large area. Click to get more potato planting techniques click to get more vegetable planting techniques