Efficient cultivation techniques of Citi leek in USA

From 2006 to 2007, Citi leek was introduced to Dafeng City, Jiangsu Province, and achieved great success through two years of cultivation. The average yield reached 9850kg per 667m2, and the benefit reached 8213 yuan. The introduction of this variety greatly promoted the planting benefit of vegetable farmers in the introduction area of Dafeng City, and became a new bright spot for vegetable farmers to get rich in Dafeng City. In the past two years, through the exploration of its cultivation characteristics and cultivation techniques, a set of practical cultivation techniques has been summarized, and the key points of its matching cultivation techniques are introduced as follows:

1 cultivation environmental conditions

Citi leek has strong adaptability and lax requirements on soil. It can be cultivated on sandy soil, loam and clay, but it is most suitable to be cultivated on slightly alkaline soil rich in organic matter, fertile and loose: upper and pH 7.7. Citi chives also have wide requirements for climatic conditions, which can withstand low temperature of-10 ℃ and high temperature of 38 ℃, but grow well in cool and humid climate, and the suitable growth temperature is 12-25 ℃. However, the drought and waterlogging tolerance of Citi leek in the United States is poor, so the cultivation site should be planted in the fields with high terrain and convenient drainage and irrigation.

2 raising seedlings

2.1 sowing

2.1.1 the determination of sowing time in open field can choose to sow seedlings in batches from March to June. If the cold bed in a small arch shed is used to raise seedlings, the sowing date can be advanced to mid-late February and the seedling age is 30-50 days. Sowing in autumn, overwintering with seedlings, bolting and flowering the following summer. Our cultivation mainly harvests seedling cultivation in small arch shed in spring.

2.1.2 the bed soil is prepared to choose the land with fertile soil quality, good drainage and irrigation, and no onion and garlic crops have been planted in the previous crop, and the soil will be ripe by turning deep frozen ridges before winter. 15 days before sowing, the seedling land was ploughed and raked evenly, and every 667m2 was applied with rotten barnyard manure 3000~4000kg, which was mixed with the soil to make a high border with a width of 1.2m to 1.3m, and then the seeds could be sown.

2.1.3 seed treatment seeds must select the new seeds of the current year, select the seeds before sowing, get rid of broken seeds and shrunken seeds, and choose full and disease-free seeds. Before sowing, the seeds were dried for 8 hours to facilitate the germination of the seeds. After drying, the seeds were soaked in 55 ℃ hot water, disinfected 10min, and picked up for sowing.

2.1.4 generally sowing 2~3kg in every 667m2 seedbed. When sowing, pour through the bottom water, sow the seeds evenly after the bed soil has enough moisture, and cover the seeds with a thin layer of dry fine soil after sowing. After emergence, it was covered with dry fine soil about 5mm thickness. If the seedlings are raised in a cold bed in a small arch shed, the support should be covered with film in time after sowing.

2.2 Seedling stage management

2.2.1 manage the shade before emergence, such as sowing in spring, sowing in autumn, covering grass or shading net after sowing, and often keep the soil moist.

2.2.2 after seedling emergence, the seedlings can emerge within 1 week after sowing, and the seedlings can be completed in about 8 days. After the seedlings are completed, the soil should be kept dry and wet, and weeds should be removed in time. In the 3-4 leaf stage, the seedling height 5~6cm time seedlings, foliar spraying 1% urea solution. When the seedling height was about 12cm, the urea solution of 5kg was applied every 667m2. When the seedling height reached 20cm, it was planted in the field. 5-8 days before planting, the seedlings were squatted under water control, and the vents were continuously enlarged to refine the seedlings until the shed was completely removed before planting.

3 colonization

When the seedling height is above 30cm and the false bolting 1cm is thick, the soil with rich organic matter and loose soil should be selected. Rake fine and flat before planting, apply rotten barnyard manure 4000kg per mu, urea 20kg, calcium superphosphate 50kg, potassium sulfate 20kg, mix with soil and rake fine. Make a high border or ridge according to 60~70cm row spacing, widen the furrow of 15cm, deep 10~12cm, single row, plant spacing 10~15cm. Root water was poured after planting. The soil was cultivated by ridge planting for 2 or 3 times during the growth period.

4 field management

The suitable temperature for the growth of leek is 18: 22 ℃ in daytime and 12: 13 ℃ at night. As the leek is not resistant to drought and waterlogging, so attention should be paid to timely watering and drainage in production. Watering seedling water in time after slow seedling, loosening soil to prevent hardening after rainfall, paying attention to drought resistance and drainage in high temperature and humidity season, watering and topdressing fertilizer in time after autumn, every 10 to 15 days, combined with urea 10~15kg per mu. Ridging cultivation, shoveling ridges and opening ditches before the rainy season to facilitate drainage. In the prosperous period, the soil was cultivated once every 10 to 20 days and continuously for 2 to 3 times in the prosperous period.

(5) Disease and pest control

The common diseases of leek are downy mildew and gray downy disease, etc., according to time and environmental conditions, we should actively do a good job in prevention and control of downy mildew. Botrytis cinerea can be controlled by spraying with 75% chlorothalonil wettable powder. Botrytis cinerea can be controlled with 50% carbendazim 600 times, and the common pests of leek are Liriomyza huidobrensis and onion thrips, which can be controlled with 2000 times of 2% avermectin EC.

(6) harvesting and seed retention

Seedling height can be harvested at 30~40cm, and it can be harvested 3 times or 4 times a year. The tools used in the harvest process should be clean, hygienic and pollution-free. If we want to collect seeds, we should adopt the cultivation method of sowing and raising seedlings in autumn, overwintering seedlings, transplanting them to the field in March, paying attention to watering and topdressing, bolting around the middle of May, watering less, increasing the amount of water in the period of flower ball formation and after flowering, and seed maturity in mid-late July. Should be harvested in time.