Potatoes often suffer from various diseases throughout the reproductive period. Autumn sowing (sowing in September) and sowing in spring (planting in January) can all cause the disease. After the occurrence of major diseases, the output is generally reduced by more than 30%, and the quality of the disease is reduced. The severely affected fields will die in pieces and even result in the loss of production. The main disease prevention techniques are as follows. Potato late blight Potato late blight, also known as blight and potato clams, is a devastating disease for potatoes. In low-lying areas, poor drainage, high humidity in the field, or excessive nitrogen fertilizer application, the incidence is more serious. When the temperature and humidity are appropriate, the disease rapidly expands and spreads, and the diseased plants die. The diseased leaves initially had round or irregular shapes at the tip and the leaf edge. The spots were dark green and stained spots. They turned brown and became large spots. When the humidity was high, a white mold layer grew in the diseased and healthy junctions. . Injuries to the stems, resulting in a slight dingy brown streaks, when wet, also produce white mold, damaged potato blocks, resulting in brown pits. Control methods: In addition to selecting disease-resistant varieties and disease-free seed potatoes, they should also: 1. Rotation of severe disease fields and non-sweet potato vegetables should be carried out for more than 3 years. Spring potato and tomato fields should be separated by 300-500 meters. 2. To strengthen the cultivation and management of reasonable application of nitrogen, phosphorus, potassium fertilizer, appropriate potassium fertilizer, and enhance disease resistance. Drain the drainage, reduce the humidity in the field, remove the diseased plants in the field, burn them in a concentrated manner, and reduce the incidence. 3. In the early stage of onset of drug control, spray the drug immediately to control its spread. Spray once every 5 to 7 days, and spray 2 or 3 times. The commonly used agents are: 64% antiviral 500 to 750 times solution, or Ledomil-manganese 58% wettable powder 500 to 600 times, or 80% wettable powder 500 times, or dakkon 40% suspension 500 to 600 times liquid agent. Rongcheng Jingyi Oceanic Technology Company Limited , https://www.jingyifoods.cn