Potato Disease Prevention and Control Methods and Key Technical Points

Disease is one of the important factors affecting the yield and seed quality of winter potatoes. The main diseases of winter potatoes in Yunnan Province and their prevention and control methods are introduced as follows:

Virus disease prevention and control methods: select virus-resistant varieties and virus-free seed potatoes; pull out diseased plants in the field; control aphids in a timely manner.

Fungal diseases: first, late blight. Prevention and control methods: select disease-resistant varieties and disease-free seed potatoes; promptly pull out central diseased plants and carry out intertillage and weeding; chemical control. Second, early blight. Prevention and control methods: select disease-resistant varieties; chemical control.

Bacterial diseases: ring rot prevention and control methods: select disease-resistant varieties and disease-free seed potatoes; promptly remove diseased plants when found; practice crop rotation and pay attention to controlling underground pests. Bacterial wilt prevention and control methods: agricultural control mainly includes: rational crop rotation. Select disease-free and disease-resistant varieties, prevent diseased and rotten potatoes from mixing into fertilizer, increase the application of phosphorus and potassium fertilizers, clear weeds in the field, promptly pull out central diseased plants when found, disinfect diseased holes with lime, and drain water promptly from low-lying land: drench the roots with 50% copper bis(gluconate) wettable powder at 500 times dilution or 14% copper ammonia complex aqueous solution at 400 times dilution, drenching once every 7-10 days, for 2-3 consecutive times. Soft rot prevention and control methods; agricultural control measures include strengthening intertillage and hilling before harvest, and paying attention to field drainage; for mature tubers during harvest and transport, avoid manual and mechanical damage. For blackleg prevention and control, seed dressing can be done with dexon at 7.5kg/hm2 or Bingkejing at 400 times dilution, or foliar spraying with 0.1% copper sulfate solution. For scab prevention and control, seed potatoes can be treated with 18% mancozeb powder or the soil can be fumigated, or seeds can be soaked in unheated formalin at 200-250 times dilution for 20-30 minutes, then removed and kept covered for 6-8 hours.