Garlic blight mainly damages leaves. At the beginning of the disease, white to yellow water-soaked spots appear at the tip or middle of the leaves. When the humidity is high, the spots spread rapidly, and then half of the leaves die to the whole leaves. . Different chemicals such as mancozeb, metsulfuron-methyl-manganese-zinc, alkenyl-manganese-zinc, cymoxazine-urea, propamocarb, propamoxicillin, Yinfali, yikuaijing and cyazofamid can be selected for continuous prevention for 2-3 times, once every 7 days.