What are the methods of planting Chinese yam to control diseases and insect pests?

What are the ways to control pests? Please give an introduction to the method of planting yam can be used to control diseases and insect pests in the following ways: 1. Agricultural control 1. The selection of disease-resistant varieties is an effective way to control yam diseases and insect pests. When planting disease-resistant varieties, rational distribution should be made, varieties should be rotated every 2~3 years, and attention should be paid to the purification and rejuvenation of varieties. 2. Crop rotation can reduce or avoid stem rot and root knot nematode damage of yam. Rotation with corn, wheat, radish, watermelon and other crops that are not infected shall be carried out at least once every 3 years; rotation shall be carried out once a year in old areas where yam is cultivated all the year round; rice-drought rotation can be carried out in areas where conditions permit, so as to achieve better control effect. 3. Soil preparation can directly eliminate pathogenic bacteria overwintering in soil. Selecting fertile loose sandy loam with high dry terrain and low humidity for soil preparation in autumn can turn over the sick and disabled bodies left on the ground into soil, accelerate the decomposition and decay of the sick and disabled bodies, and make some pathogens lose their vitality after winter freezing and spring drying. 4. Fertilization, irrigation yam is a fertilizer-loving crop, in the preparation of soil must apply decomposed organic fertilizer. Generally, phosphorus and potassium fertilizer are beneficial to the formation of yam mechanical tissue and enhance the ability to resist pathogenic bacteria. Too much nitrogen fertilizer, easy to cause excessive plant growth, stem and leaf tissue soft, easy to get yam anthracnose. The principle of watering is "no drought, no watering". Clean water should be used when watering. It must be watered thoroughly. There should be no accumulated water in the field. Drainage should be carried out in time in rainy season to avoid root rot. 5. Field surface cleaning field weeds had better be eradicated manually. Removing the leaves and stems of diseased yam in time can reduce the reinfection of pathogens. When yam is harvested, the sick bodies, weeds and rotten stems left on the ground should be burned or buried deeply outside the field to reduce overwintering pathogens. Second, chemical control 1. yam anthracnose harm stems and leaves caused by stem blight, deciduous. Control method: seed potato with 1∶1∶150 wave of multi-solution soaking for 10 minutes. 50% carbendazim 600 times solution was sprayed for the first time when seedling was complete, and the second time was sprayed after 10 days. From July to August, 500-fold solution of 65% manineb WP, 800 - 1000-fold solution of 50% tuijunte WP and 700 - 800-fold solution of 50% thiophanate-methyl were sprayed alternately for 2 - 4 times according to the severity of the disease. Every time 8~10 days interval, after the rain should be sprayed liquid medicine. 2. Short body nematode disease causes dwarfing of plants, yellow and dead in severe cases; tuber damage causes small nodules of different sizes, affecting yield and quality. Control method: Before sowing, treat the soil with pesticide, mix 5kg of 5% methamidophos granules with 100kg of moist fine soil per mu, ditch evenly spread on both sides of seed potato, or evenly spread in combination with soil preparation, 25~ 30cm into the soil. 3. Tenthreds bite yam leaves, causing serious leaf loss, affecting photosynthesis and reducing tuber yield. Kill with 2% trichlorfon 3000 times solution or 90% crystalline trichlorfon 1000 times solution stem spray. 4. Grubs bite tubers, making them not rotten and bitter. Control by soil treatment, 50% phoxim 250- 300ml per mu, 25kg fine soil mixed and then scattered into the ridge, after application immediately inserted into the 20cm soil layer, and then planted yam seeds. Click for more yam growing techniques Click for more vegetable growing techniques