How should field management be carried out after planting yam?

YamThe roots go into the soil relatively shallowly, so deep intertillage is generally not carried out to avoid damaging the roots; weeds can be removed as needed. After routine watering, soil can be appropriately hilled up along with loosening the soil. To increase soil temperature, watering is generally done after the seedlings emerge evenly, but the soil moisture at planting time should be suitable. After the yam seedlings emerge, only 1 strong bud is kept per plant, and all the other buds are removed. Topdressing is carried out in mid-June; if sufficient soil manure and bean cake were not applied, shallow furrows can be opened between the rows for fertilization. In early July, fertilizer is applied together with watering according to growth. During this period, no basal fertilizer can be applied; before rain, apply about 15 kg of urea per mu. A 0.2% potassium dihydrogen phosphate or 0.2% urea solution can also be sprayed, and during the vigorous growth period, plant growth regulators can be sprayed as appropriate. From early August to early September, appropriately spray expansion agent.

Pest and disease control

(1) Yam pest and disease control must adhere to the principle of giving priority to prevention, with prevention more important than cure, in order to achieve twice the result with half the effort. Once yam pests and diseases occur, they are relatively difficult to control. Therefore, pesticides should be applied before the disease occurs, and trellis poles used in previous years should be soaked in fungicide before being inserted for trellising. In mid-to-late May, when yam seedlings are about 1 m tall, pesticide can be sprayed to prevent disease.

(2) Anthracnose, leaf spot, brown spot, and white astringent disease can be controlled with 70% mancozeb at 500-600 times dilution, or 50% thiophanate-methyl at 700-800 times dilution, or 80% carbendazim-anthracnose wettable powder at 800 times dilution, sprayed once every 7-10 days for 2-3 consecutive sprays, with timely re-spraying after rain. For white astringent disease, in early June, foliar spraying can be done with basic copper sulfate suspension concentrate at 400-500 times dilution, or 50% thiram wettable powder at 500-600 times dilution, or 75% chlorothalonil wettable powder at 700-1000 times dilution.

(3) Stem rot and fusarium wilt can be treated by drenching the roots with 50% carbendazim at 400 times dilution, or 75% chlorothalonil at 600 times dilution, or 95% dexon at 200-300 times dilution 2-3 times, once every 10-15 days. For fusarium wilt, root drenching can be done with 50% carbendazim wettable powder at 600-700 times dilution, or 70% mancozeb wettable powder at 500 times dilution, once every 10-15 days for 5-6 consecutive drenchings.

(4) Yam sawfly can be controlled with 50% dichlorvos at 1000 times dilution, or 50% phoxim at 1200-1500 times dilution.

(5) Red spider mite can be controlled with 40% omethoate emulsifiable concentrate at 1000 times dilution.

(6) If underground pests such as cutworms, white grubs, mole crickets, and wireworms are found, use targeted pesticides mixed with poison bait for control.