Cultivation techniques of high yield and high quality of Chinese chive with plastic film

Leek is one of the most popular vegetables eaten by citizens in Northwest China all the year round. In recent years, due to the inadequate management measures of some farmers, the quality of fresh leeks and leek bolts has declined year by year, and some farmers have applied a large number of chemical pesticides indiscriminately, resulting in excessive pesticide residues in leek products, causing a serious threat to the health of consumers. In the past three years, in order to effectively implement pollution-free production and achieve high yield, high quality and high efficiency, through in-depth comprehensive production demonstration, a high quality cultivation and production base of pollution-free leek has been established in the demonstration area, and the following key cultivation techniques have been taken:

1. The suitable cultivation area was selected to establish the concentrated planting area of pollution-free leek, and the pollution-free producing area of production was identified.

2. Select excellent varieties. In the cultivation of leek covered with plastic film, Lanzhou early bolting and Malian leek with medium tillering ability, thick green leaf color, thick pseudostem, thick leaf, early bolting and good quality should be selected.

3. The seed propagation and seedling transplanting method should be adopted in the production, and the mother plant planting method should be put an end to as far as possible. Through the comparative observation in recent years, the seed seedling transplanting has the advantages of vigorous growth, good product quality and obvious yield advantage.

⑴ should take care of raising seedlings and cultivate strong seedlings. When sowing, choose pure and full seeds to sow. The seedling sowing field should apply 5000 kg of high-quality farm manure per mu last autumn and winter, and fully irrigate winter water, and apply 10 kg of urea, 50 kg of common phosphorus and 10 kg of potassium sulfate per mu in the following spring. Ploughing and ploughing flat to be sown. Dry seed sowing is used before and after March 20 to April 10 every year. The amount of seed used for transplanting is 0.5-0.8 kg per mu, and the seedling bed is 67 square meters. The soil thickness is 1-1.5 cm when sowing, and the soil surface is watered 3-4 days after sowing to ensure the soil surface is moist.

⑵ strengthens the management of seedling stage. The focus of seedling management is watering and weeding. When the leek is unearthed, it should be watered gently, and then watered after the surface is exposed. With the growth of the seedlings, the watering days will be gradually prolonged and the amount of water will be increased. From the seedling to the seedling height of 16 cm, about 7 days to irrigate a water, and follow the water to apply urea 5 kg per mu. After the seedling height is about 10 cm, the weeds in the seedbed should be pulled out 2-3 times in time to facilitate the growth of leek.

⑶ transplanting method and post-transplanting management. The northwest region is generally transplanted from late July to early August (for example, leek seedlings can be transplanted in the early spring of the second year). When transplanting, a single row of deep trench planting method is adopted, and the seedling pool is watered thoroughly before transplanting, the leek seedlings are cut off and the apex of fibrous root is left 2-3 cm, and the leaves are cut off to reduce foliar evaporation. The ditch is opened according to the row spacing of 40 cm, and the ditch depth is about 15 cm. The seedlings are placed in the ditch according to the plant spacing of 1-1.5 cm, and the soil is watered and covered with soil. it is appropriate to cultivate the soil without burying the leafy nodes during planting, and the leek ditch is 4-6 cm lower than that between the rows after soil culture. in order to cultivate soil year by year to achieve high yield. After planting, continuously irrigate 2 water, loosen the soil and squat seedlings in time, and then keep the soil dry and wet. Leek grows to 15 cm high, combined with watering diammonium phosphate 10 kg per mu, and then topdressing again at intervals of 20 days. The weather is cooler after the beginning of autumn, so it is necessary to timely control the water and pour enough winter water before the soil is frozen.

4. To promote the key technology of promoting strong and early germination. The purpose of plastic film mulching of leek in early spring is to promote early germination and supply to the market in order to achieve seasonal difference and high benefit, so three key measures should be implemented in cultivation measures: first, to carry out root-raising and health-promoting management measures for Chinese chives planted in the first year. The second is to stop harvesting fresh leek in autumn after harvesting 2-3 knives in spring and summer in each cultivation year, in order to accumulate nutrients and return to the leek root, to ensure early growth and rapid development after plastic film mulching in early spring, and good quality of fresh leek; third, to renew and rejuvenate after 4-5 years of production, and to replant seedlings and transplant seedlings, only in this way can we continue to maintain the yield and quality advantages of fresh leek and leek.

⑴ film mulching mode. In the second year, the whole field was covered with 1.8-2 m wide plastic film on the leek ridge in the middle of February, the plastic film was sealed between the rows with bricks and soil blocks, and the first stubble (knife) was harvested in the middle and late March. After harvest, the soil around the leek stubble was hoed loose, and the soil was gradually cultivated in the leek root. The plastic film can be covered with plastic film after the first stubble is harvested and dried for 1 day, and the plastic film is removed after the second knife harvest, and the third knife is harvested in the first ten days of May, and the leek stalks are harvested in early June and listed in the middle and late August.

⑵ water and fertilizer management. 2-3 days after each harvest, the leek wound healed and fertilized when the new leaves grew. 400 kg of rotten organic fertilizer, 10 kg of urea and 10 kg of compound fertilizer were applied per mu. During the period of harvesting leek bolts, attention should be paid to watering management, with the basic principle of seeing dry and wet.

⑶ strengthens the management of summer and autumn. Turn the leek root in time after stopping harvesting in the middle and late August. The method is to pick up the leek leaf with a stick to make it fall on one side of the row, and then turn it over on the other side of the row after half a month. After killing the leaves on the ground by early frost, the dry leaves on the ground will be cut off in the middle of October, that is, tillage and controlled fertilization will be carried out for the next year.

⑷ re-applied base fertilizer in winter. Before winter irrigation, 100 kg of ammonium bicarbonate per mu and 40 kg of calcium superphosphate were dug in the ditch, while the stuffy head fertilizer was re-applied, and 8 cubic meters of high-quality mature farm manure was applied per mu to provide sufficient nutrients for the germination of leek in early spring. it is helpful to improve the soil temperature and lay the foundation for high yield in the coming year.

6. Pest control. The control technology of diseases and insect pests is the key link in the production of pollution-free leek. We should thoroughly select chemical pesticides with safety, low toxicity and low residue, strictly control the appropriate period and effective dosage, and strictly grasp the safe interval between application and harvest.

The main diseases and insect pests of plastic film leek are leek maggot, Botrytis cinerea and blight.

Leek maggots: use vinegar to trap and kill adults; use sugar, vinegar, wine, water and 99% trichlorfon crystal 3 to 1, 10 to 0.6 to form a solution, put 2-3 pots per mu, and add it at any time, which can be trapped and killed during the epidemic period of adult seed flies. Chemical application in the field can be carried out 2 days after head knife harvest in mid-late March or in mid-late September in late autumn. 1000 times of phoxim EC or 1000 times of trichlorfon crystals are often used to irrigate the roots along the furrow (spray roots).

Botrytis cinerea: 1000 times of 50% Sukeling wettable powder and 1000 times of 50% prohydantoin wettable powder were sprayed on the second day after the leek was harvested.

Blight: 600-fold solution of 60% metalaxone wettable powder and 600-800-fold solution of 72.2% Pulicol water agent were sprayed on the second day after Chinese chive harvest.