Planting green onions and doing a good job of field management in autumn

The center of autumn field management of scallion is to promote roots, strengthen trees and cultivate soil softening, strengthen fertilizer and water management to create suitable environmental conditions for the formation of scallion white, and improve the yield and quality of scallion. 1. Watering: After planting, the management center of scallion is to promote roots. Watering should be controlled. Drainage and waterlogging prevention should be carried out after rain to prevent rotten roots, yellow leaves and dead seedlings. At the same time, intertillage should be strengthened to promote root growth. Between the beginning of autumn and white dew, irrigation should master the principle of light irrigation and watering in the morning and evening. After white dew, scallion enters the peak growth period, watering should master the principle of frequent watering and re-watering, watering once every 4-6 days. Spraying 800 times of new lipid film solution to keep moisture, prevent evaporation of water and isolate invasion of airborne bacteria; after frost, the temperature decreases, the onion basically grows, the water demand decreases, and the watering should be stopped 5-7 days before harvest, which is beneficial to harvest and storage. 2. Topdressing: Scallion should be topdressed in stages on the basis of applying sufficient base fertilizer. After the beginning of autumn, when the growth of plants is accelerated, topdressing "leaf attack fertilizer" is applied, and decomposed farm manure 1500-2000 kg and calcium superphosphate 20-25 kg are applied per mu to promote leaf growth. After the white dew festival, it enters the peak growth period of scallion white, which is the key period for the formation of onion yield. It should be combined with watering and topdressing twice. Urea 15- 20kg and potassium sulfate 10- 15kg should be applied to each mu each time. The topdressing should be sprinkled between rows. Watering after shallow cultivation, and spraying new lipid film to improve the utilization rate of effective components of fertilizer. 3. Cultivate soil: Cultivate soil is an important measure to soften leaf sheath, prevent lodging and improve yield and quality of onion. From the beginning of autumn festival to before harvest, generally cultivate soil for three times, the first two times combined with cultivation, the ridge soil will be blocked into the onion ditch, after summer heat will fill the ditch; The height of soil cultivation for each time of onion shall be determined according to the growth height of false stem, 3-4 cm each time, soil cultivation shall be carried out to the leaf outlet of the uppermost leaf, and the heart leaf shall not be buried to prevent the leaf from rotting. In combination with soil cultivation, strong stem spirit shall be sprayed in time to make garlic plant stem thick, leaf plump, fresh leaf color, natural taste thick and high commodity value. 4. Seed collection. There are two kinds of seed collection methods: adult plant and semi-adult plant. Seed collection of adult plants: use spring onions fully grown in autumn as seed plants, which is convenient for strict seed selection, but the cost is high, and is used for breeding original seeds; seed collection of semi-adult plants: sow and cultivate semi-grown plants in summer as seed plants, and transplant them before winter, with low cost and shortened cycle by one year. Scallion is easy to cross-pollinate, and seeds should be isolated among varieties. Spring onion harvested in early winter, after harvest planing and drying, arranged into bundles, discharged in the shade of shallow ditch. It can be stored at low temperature below 0℃ for more than 100 days. During storage, keep the onion bundle slightly frozen and avoid repeated thawing. The air humidity should be about 80%, and it can be covered with grass to keep moisture and rain. Welsh onion has no natural dormancy. Although pseudostems can be stored for a long time at room temperature, they are worn out greatly.