American Citigroup leek

Leek also known as sea garlic, garlic seedlings, flat leaf onion, lily family onion, biennial herbs. Originated in central and southern Europe, it was introduced into China at the end of the 19th century. Because leaves, pseudostems and flower buds are edible and rich in carbohydrates, they are often used instead of garlic sprouts for food or export after dehydration processing. The economic benefits are very significant. In 1992, our institute introduced "American Citi Leek" from abroad. In the past 8 years, it has been popularized in Fujian, Guangxi, Guizhou, Sichuan, Shanghai, Zhejiang, Hubei, Hunan and Shaanxi, with a cumulative area of 6500 hm2, which is very popular among vegetable farmers and consumers. The characteristics and cultivation techniques are described as follows.

I. Characteristics

Strong growth potential, plant height about 70cm, pseudostem white as onion, leaf body flat like garlic, leaf long lanceolate, single leaf alternate, wax powder outside, width 2.5~ 5 cm, length 30~50cm, round leaf sheath to generate pseudostem, outer skin membranous, white, flower bolt solid, round section, base thick 1 cm, length 80cm. Rarely pest, cold tolerance, wide adaptability, can tolerate high temperature of 38℃ and low temperature of-10℃, suitable day temperature for growth is 18~22℃, night temperature is 12~13℃. The root system distributes shallowly, does not endure drought, also does not endure waterlogging, must irrigate and drain in time in the production. Leek belongs to green vernalization type. It needs 4~5 leaves seedling stage to change from vegetative growth to reproductive growth. After a long period of low temperature of 5~8℃, flower bud differentiation occurs, and then it encounters long day, and flowers sprout at 18~20℃. The flower stalk is an umbel with an involucre outside. When flowering, the involucre is unilaterally cracked and shed. There are 800~3000 florets, pale purple or pink. The flowers generate balls, bright and beautiful. The seeds are angular, black and have a thousand grain weight of about 2.8g. After sowing, it can be harvested continuously for 7~8 years (the harvest situation is the same as that of leek), and the annual yield of tender seedlings and flower buds is 6500~8000kg per 667m2.

II. Key points of cultivation techniques

1. The sowing time is suitable for harvesting the annual plants for production purposes. In northern areas, seedlings are generally raised in mid-March, planted in mid-June, and harvested in late October. Before seedling preparation, apply basal fertilizer, make seedling bed 6~8m long and 1~ 1.5 m wide, planting 667m2 leek needs seedling bed 100~130m2. Water is poured on the surface of the ridge, seeds are evenly spread after water infiltration, and the soil is covered with a thickness of 1cm. To harvest tender seedlings for the purpose of production, can be sown in late spring and early summer, the tender seedlings can be harvested in the same year market.

2. Cultivate strong seedlings and keep the topsoil moist after sowing to facilitate seedling emergence. After seedling emergence, sprinkle a layer of sieved fine soil on the surface of the ridge to preserve moisture and promote rooting. Irrigate in case of drought, keep the surface of the ridge dry and wet, and weed in time. When seedlings had 3~4 leaves, combined with irrigation, ammonium sulfate 10kg/667m2 was applied to promote rapid growth. If the seedlings are dense, the seedlings should be thinned in time. If there is a tendency of excessive growth, irrigation should be controlled. Irrigation should be done once 1~2 days before planting to facilitate seedling emergence.

3. Rational close planting, removal of residual plants and weeds of previous crops, leveling of land, spreading of farm manure 5000~7000kg per 667m2, deep harrowing, uniform mixing of manure and soil, making 20cm wide beds, 20 cm spacing between beds, planting 3 rows per bed according to row spacing of 7cm, plant spacing of 7cm, planting 126 seedlings per m2, 84 thousand seedlings per 667m2. Planting depth should not be buried to the heart leaf, irrigation immediately after planting. This planting method due to high density, small plant, rely on population yield.

4. After planting management, when the leaves begin to grow, irrigate once, and loosen the soil when the topsoil is dry and wet, so as to promote root growth. July, August temperature is higher, rainfall is heavy, in addition to keeping dry and wet, after the rain should be timely drainage waterlogging prevention. After September, the climate conditions are suitable, the growth is rapid and vigorous, irrigation and topdressing should be timely, the soil should be kept moist frequently, combined with irrigation for topdressing, urea 10kg should be applied every 667m2 in the vigorous growth period, and urea 10kg should be applied half a month later. And cultivate soil twice, soften pseudostem, improve yield and quality.

5. The flower stalks of cultivated leek are very similar to garlic stalks, except for slightly lighter pungency and smaller involucre, there is no big difference between them in morphology and nutritional components, so they can be marketed as garlic stalks.

Special production of flower sprouts, in the open field can be safe winter areas can be autumn sowing, adopt the same cultivation density as garlic, winter irrigation, to ensure safe winter. After germination and growth in spring, due to the vernalization stage, high temperature and long sunshine were encountered in May, and bolting was carried out quickly. When the flower sprouts grow to a certain extent and the quality and yield reach the best, they can be cut on the ground and peeled off the leaves and leaf sheaths. The yield of garlic sprouts is higher than that of garlic sprouts. This mode of production has lower cost and higher benefit.