Six Improvements in No-Till Cultivation of Autumn Potatoes with Rice Straw Mulching

Autumn potatoes can be harvested in December and marketed as vegetable potatoes, giving relatively good returns. Adopting no-till cultivation of autumn potatoes with rice straw mulching not only saves labor and time, reduces labor intensity, and prevents environmental pollution caused by burning rice straw, but also yields about 1500 kg per mu, an increase of more than 10% over plowed and sown crops. Especially in recent years, in conjunction with production demonstrations, agricultural technicians have made some improvements to this technology, making it further mature. Specifically, these are the "six improvements":

Switch to early-maturing excellent varieties. The effective growth period of autumn potatoes is short, generally only 80 to 90 days, so seed potatoes should be switched to varieties with early maturity, fast tuber expansion, and good yield and disease resistance, such as Dongnong 303, Holland 15, and others.

Change late sowing to timely sowing. When autumn potatoes are planted following mid-season rice, sowing is often too late, causing a shortened growth period and low yields. Of course, sowing too early must also be avoided.

Generally, sowing is appropriate when the daily average temperature steadily drops below 15 degrees. In low mountain areas at 500-800 m altitude, sowing in late August is appropriate; in areas below 500 m altitude, the suitable sowing period is from late August to early September. Therefore, mid-season rice fields with an earlier maturity period should be selected for planting.

Change sowing without sprouting to sowing with sprouting. At autumn sowing time, the temperature is still relatively high, which is unfavorable for seed potato sprouting; sowing without sprouting often results in late and extremely uneven emergence. In view of this, 7-10 days before sowing, seed potatoes should be soaked in "920" solution to promote sprouting (if spring potatoes used as seed have already sprouted, sprouting is not necessary). For small whole seed potatoes, soak in "920" solution at a concentration of 4 parts per million for 20-30 minutes; for large potatoes, cut them into 2-4 pieces, first soak in 1% potassium permanganate solution for sterilization, take them out and drain off the water, then soak in "920" solution at 1 part per million for 5-10 minutes. Take out the seed potatoes, air-dry them, and then use a sand bed to promote sprouting. That is, on the indoor floor, spread a 4 cm thick layer of moist fine sand (moist enough to hold together when squeezed by hand and to crumble when touched), place seed potatoes on it, and spread a second 1 cm thick layer of moist sand. After laying 3-4 layers of seed potatoes in this way, cover with 4-6 cm thick moist fine sand, then cover with rice straw and plastic film to maintain moisture. After sprouting, they can be sown.

Change wide beds with shallow furrows to narrow beds with deep furrows. With wide beds and shallow furrows, drainage is poor during autumn rains, and rice straw soaked in water causes tuber rot; in autumn drought, it is also inconvenient to irrigate against drought. When harvesting rice, cut the rice level with the mud, make narrow beds, and open deep furrows. Divide beds at a width of 1.6 m, with furrows 15 cm wide and 20 cm deep; at the same time, open main furrows and surrounding furrows well, so that the three types of furrows are fully matched. When sowing, according to a row spacing of 30 cm and a hill spacing of 23 cm, place the seed potatoes on the bed surface so that they are in close contact with the soil. After sowing, if drought occurs, pay attention to irrigation to resist drought; if autumn rain occurs, drain water to prevent waterlogging.

Improve the fertilization method. After placing the seed potatoes, apply 50-60 kg of ternary compound fertilizer evenly between the rows, keeping a distance of 7-8 cm from the seed potatoes, and it must not contact the seed potatoes; apply 1500 kg per mu of high-quality, thoroughly decomposed farmyard manure as covering fertilizer for the seed potatoes. Then use 1000 kg per mu of rice straw to cover the bed surface, keeping it perpendicular to the bed surface, so that it is uniform with no light leakage and no exposed soil. During the growth period, pay attention to foliar topdressing 2-3 times with a mixed solution of 0.2% potassium dihydrogen phosphate and 0.5% urea.

Change no pest and disease control to pest and disease control. In autumn, attention should be paid early to using 10% imidacloprid (imidacloprid, Yibianzheng, Dagongchen) to control aphids, and using 5% Junduqing or 20% Virus A to control viruses.