Film mulching cultivation techniques of Winter planting Potato in Nanyang Basin

Potato is a grain and vegetable crop. Winter potato is one of the ideal winter crops at present. In Nanyang Basin, there are few disasters in spring potato production, and it can ensure the supply of vegetables in early summer and off-season, so the economic benefit is relatively high. In recent years, the cultivation area is increasing, and potato has become the main cash crop of local farmers in some places. Nanyang basin winter potato cultivation techniques are described as follows.

1. Select fine varieties. The effective growth period of mulched potato planted in Nanyang Basin in winter is about 90 days after full seedling. Seed potato should be selected from vegetable, virus-free and high-yield varieties suitable for local growth, such as "Dabaihua". Select the potato pieces with sunken bud eyes, no disease spots, no wormholes and no wounds. Each 667 square meters (1 mu) requires 150~200 kg of seed.

2. Land selection and preparation. Nanyang Basin is dry and rainy in spring, so it is necessary to select plots with convenient irrigation and drainage, deep tillage layer, medium fertility and no potato and other solanaceous crops planted in 3 years. Deep plough the soil 20~25 cm after harvest. In the first ten days of December, 20 kg urea, 25 kg calcium superphosphate and 20 kg potassium sulfate were applied to every 667 square meters, and shallow tillage, harrowing, raking and ridging were carried out. Ridge width 110 cm, ridge width 80 cm, furrow width 30 cm, furrow depth 25 cm.

3. Sowing. The suitable sowing time of potato covered with plastic film in Nanyang Basin in winter is from the end of December to the beginning of January. Before sowing, cut the seed potato into pieces according to the size of the potato pieces, generally cut into 20~30 grams per piece. Cut the pieces lengthwise so that each piece has a bud. After the potato seeds are cut into pieces, spray and disinfect with 0.2% carbendazim or chlorothalonil (50kg water plus 100g medicine) solution, and spray wet. Each ridge hole planting two rows, row spacing 40 cm, hole spacing 20 cm, angle arrangement, density per 667 square meters 6000 plants. 30kg of ternary compound fertilizer containing 15% nitrogen, phosphorus and potassium and 100kg of plant ash were applied to every 667 square meters of holes, and planted after mixing well with hole soil. Sowing depth 6~8 cm, watering after sowing, covering soil, sealing with herbicides and then covering tightly.

IV. Field management. (1) Assisting seedlings to emerge from membrane. At the end of February and the beginning of March, the seedlings break the membrane in time after kernel emergence to help the seedlings emerge from the membrane. Specific methods: in the seedlings will be above the plastic film pound L small hole, carefully take out the seedlings with soil after the plastic film at the base of the seedlings sealed tightly. (2) Water drainage. Generally, the relative moisture content of soil is maintained at 60%~80%, which is suitable for potato growth. In Nanyang Basin, 4 times of watering were needed in the middle and late stage of plastic film mulching potato planting in winter, one time in seedling stage, rosette stage, bud stage and tuber stage respectively. When watering, the ridge surface should be infiltrated evenly. During the tuber setting period, flood irrigation should be prevented to avoid potato rot. Stop watering 1 week before harvest. To low-lying land, furrow catchment should be timely drainage. (3) Cultivation and cultivation. After potato emergence, timely weeding of furrows: kernels and protection of ridge surface and plastic film integrity. The late growth to film, combined with cultivating soil. The functional leaves should not be damaged when removing film and cultivating soil. (4) Control overgrowth. If the soil fertility is high and the humidity is high, the plant has the tendency of excessive growth of internode length, large leaves and significantly tender branches and leaves, paclobutrazol with a concentration of 0.005%~0.01% can be sprayed at the middle stage of plant development and bud stage, which can not only inhibit the growth of plants, but also promote the enlargement of tubers. (5) Pest control. In the middle and late stages, 28 star ladybugs were controlled in time and underground pests were trapped. For fields prone to late blight, Bordeaux mixture (1∶2∶200) can be used to control it early in the early stage of disease, and field inspection should be strengthened to remove diseased plants immediately to prevent disease spread. Chemical control: spray with mancozeb 1000 times or 75% chlorothalonil 600~800 times solution.

5. Harvest. Plastic film potato planted in Nanyang basin should be harvested in time at the later stage of expansion. Harvesting should be done when the weather is clear and the soil is dry. Harvest in mid-May can increase 0.2~0.3 yuan per kilogram. The harvest should be finished by the end of May at the latest, so as not to affect summer harvest and summer planting.