Planting technology of Chinese yam

Chinese yam is a plant of the genus Dioscorea in Dioscorea zingiberensis, one of the four major yam (Huai yam, Achyranthes bidentata, Radix Rehmanniae, Huai chrysanthemum), produced in ancient Huaiqing (now Jiaozuo City, Henan Province), and is also known as Ma Yam in Hebei and other places. Chinese yam is a perennial herb, stem trailing, often purplish, root cylindrical, leaves opposite, ovate or oval, flowers milky white, dioecious. The root tuber contains starch and protein and is edible. Production: Henan, Hunan, Hubei, Shanxi, Yunnan, Hebei, Shaanxi, Jiangsu, Zhejiang, Jiangxi, Guizhou, Sichuan, Shandong and other places. On the banks of Sihe River, Taiping Town, Shandong Province, the output of yam is small, but the quality is very high, and it has a long history. It was a tribute in Qing Dynasty. It can cook porridge with Qiongzhen Ganoderma lucidum. It can be stewed with spareribs and can lower blood sugar. It is an ideal food for diabetic patients.

Soil preparation and trenching

Chinese yam is a shallow root crop with a long growing period and one crop a year. It is generally planted in the field when the ground temperature reaches 10 ℃ in spring. The cultivation of yam should choose sandy loam or light loam with high dry terrain, good drainage, deep soil layer and soft loam, which requires the same soil quality and the soil should be slightly acidic to neutral. It is not suitable for continuous cropping of yam. Generally, yam should be rotated once every 2-3 years.

When digging cultivation ditches, it is generally about 1 meter apart, 0.6-1.0 meters deep and 25 centimeters wide. When digging ditches, the topsoil and the subsoil are stacked separately so that the soil can be fully weathered. After the soil is thawed in spring, the lower soil is first filled into the ditch, and then the topsoil is filled so that the soil layer is not disturbed. Combined with the general soil filling, 1000 Mu of miscellaneous fertilizer will be applied to 1500kg, phosphate fertilizer 50kg-70kg, ammonium bicarbonate 25kg-30kg, potassium sulfate 25kg-30kg. Do not apply a large amount of immature organic fertilizer to prevent root burning and tuber bifurcation.

Seed block treatment

The hard root head at the top of the disease-free block was selected 20-25 days before planting, and one end of the root was dipped in hydrated lime powder, and then exposed to the sun for a few days to sterilize and promote germination. In order to increase the reproduction coefficient, the root tuber must be cut off and propagated. That is, select a thinner root with a length of about 1m and a transverse diameter of 2.4-4.5cm, cut it into several small segments with a length of 15-20cm, and write down the upper and lower ends with a brush, then dip each section in lime and dry the seeds in the sun horizontally until there are fine cracks at the end of the section. Handle gently during the sowing period to prevent bruising. At the same time, we should do a good job in preventing wind, rain and frost.

Chinese yam planting

After the yam cultivation ditch is filled with soil fertilizer, the ditch is made into a flat bed about 1 meter wide. When planting, open a planting ditch about 10 cm deep in the middle of the flat bed, and then water it. When the water seeps down, the yam plant will be spread in a single row according to the plant spacing of 15 cm to 20 cm into the ditch, planting-4000 plants per mu. Cover soil 8cm, then cover with plastic film to preserve soil moisture, increase soil temperature and promote seedling emergence. The use of "yam beans" to breed yam seeds can be planted in two rows in a row to improve the reproduction coefficient, with a row spacing of 40 cm to 50 cm and a plant spacing of about 10 cm. Plant about 12000 plants per mu.

Post-planting management

The stems and leaves of Chinese yam prefer high temperature and dry environment and are not resistant to frost. The daily average temperature of root tuber began to germinate above 10 ℃, and the optimum temperature for germination was about 25 ℃. 25 ℃-28 ℃ was the best for stem and leaf growth, and 20 ℃-24 ℃ was the fastest for tuber expansion. It takes 35 days for Chinese yam to emerge after planting.

1. Framing and drawing vine: the aboveground stem of Chinese yam is delicate, and the vine should be supported in time after emergence. According to the right-handed characteristics of the stem of Chinese yam, the vine spirals up, and the height of the frame is about 1 meter. If there are too many lateral branches at the base of the main vine, they can also be removed properly to facilitate ventilation and light transmission. When a large number of "yam beans" are formed in the axils of the leaves, some of them can also be removed as early as possible to save nutrients.

2. Medium ploughing and soil cultivation: in the early stage of growth, the weeds should be ploughed and weeded on duty, usually once every half a month, until the stem has been on the upper shelf, and then the weeds will be pulled out. It is necessary to dig up a part of the soil between the rows outside the shelf and fill it into the inner row, so that a high border is formed inside the shelf, and a furrow of deep 2Ocm and wide 3Ocm is formed between the outer row of the shelf, so that it can be drained in the rainy season.

3. Timely chemical control: paclobutrazol can obviously inhibit the growth of aboveground part of Chinese yam, inhibit the occurrence of residual seeds, and increase the yield of Chinese yam by more than 10%. The best time to spray paclobutrazol is when the Chinese yam is full of vines. In the early stage of bud flowering, 60-70 grams of 15% paclobutrazol wettable powder per mu and 50 kg of water are sprayed evenly. Overgrown fields can be sprayed for the second time every 7-10 days.

4. Reasonable topdressing: topdressing 1 times when the stem vine has been on the top shelf, generally applying 2535 kg high concentration compound fertilizer per mu. Or 20 cm from the plant to open a ditch to apply rotten organic fertilizer 500 kg to 1000 kg. Fertilize and water. In the future, when the stem is full of vines, if there is a phenomenon of yellow weight loss, urea 10kg/ mu can be applied again. In the later stage of growth, combined with disease prevention and insect control, 0.3% potassium dihydrogen phosphate solution 2Murray was sprayed outside the root for 3 times to protect leaves and prevent aging.

5. combination of drainage and irrigation: Chinese yam is a drought-tolerant crop, but it should be watered properly in order to achieve high yield. Generally before and after the first topdressing, if there is no rain for a long time and the soil is fully whitened, it should be lightly watered 1-2 times until the soil surface is moistened. From now on, at the turn of summer and autumn, if the dry and hot weather lasts more than a week, you should also pour cold water in the early morning to fight the drought. Chinese yam is more afraid of waterlogging, rainy season should timely clear ditches and drainage, so that there is no stagnant water in the field.

Timely harvest

After the first frost, the aboveground stems and leaves gradually withered and yellow, and the underground tubers went into a dormant state, which can be harvested and sold or stored in the vegetable cellar. You can also cultivate soil on the planting bed to prevent frost, and keep the land for use and harvest.

Pest control

Golden needle worms, mole crickets, grubs, the yam underground tuber drilled many holes, sometimes hidden in the tuber dormancy. Golden needle worm itself has a layer of membrane, the drug is not easy to penetrate its body contact, stomach poison is better. Comprehensive measures should be taken to prevent them as follows:

1. Turn the land 25-30 cm deep before winter, turn the overwintering adults and larvae to the surface, make them freeze to death, sun to death or be preyed on by natural enemies.

2. Fertilizing mature organic fertilizer fully mature organic fertilizer can change the aeration and permeability of soil, make crops grow healthily, and enhance disease resistance and insect resistance. Crop rotation is also a powerful measure to prevent disease and insect pests, and it is generally better to rotate every 3-4 years.

3. Poison Valley is made of 0.15 kg 90% trichlorfon 30 times liquid, mixed with blighted grain, 1.5-2.5 kg per 667 square meters. Sprinkle it on the surface of the soil and loosen the topsoil with a hoe so that some medicine is in the soil and some is on the soil surface.

4. Poison erbium 0.15 kg 90% trichlorfon 30 times liquid, mixed with 5 kg of fried wheat bran or bean cake (or cottonseed cake) to make poison erbium. The effect is good in the stifling evening, and 1-1.5 times the weight of erbium should be added when mixing. Or use 40% 50% dimethoate 100 grams mixed with 5 kg of water to stir-fry 50 kg of erbium materials (wheat bran, bean cake, corn crumbs, etc.), planing every 2 meters, every 3-4 meters planing a large hole, put a pinch of poisonous erbium and then cover the soil, 1.5-2.0 kg of poisonous erbium every 667 square meters. This method is very good for the control of mole cricket and grubs.

5. 1500 times of 40% methyl isophosphates EC was used for root irrigation, and 0.15kg to 0.2kg per plant. Or use 2% methyl isosinophos powder, 3-4 kg per 667 cubic meters, sprinkle on the near-plant topsoil, and then mix the soil and powder well with a hoe. This method has a special effect on the control of grubs and golden needle worms. Or use 90% trichlorfon 800 times solution, 0.15-0.2 kg per plant.