Artificial cultivation of Glycyrrhiza uralensis

Licorice, also known as sweet root, dense grass, there are 23 varieties in the world. China is the country with the largest distribution of licorice, with 12 varieties. Ural Glycyrrhiza uralensis (Glycyrrhiza uralensis) is the most widely distributed, the highest yield and the best quality of the six species of licorice listed in the Pharmacopoeia of China, and has enjoyed a high reputation in the international market for a long time. Licorice is a perennial herb, Leguminosae, whose roots and rhizomes are used to reconcile the effects of various medicines and antidotes in traditional Chinese medicine. In China, there are "ten square nine herbs" and "there is no grass without a square", so it is called the king of Chinese herbal medicine. The market demand of licorice has been on the rise, and relying on mining and digging wild resources is far from being able to meet the demand. The worldwide shortage of licorice has caused the price of licorice to rise in turn, from 700USD / t in 1981 to US $3000 / ton now. Therefore, artificial cultivation of Glycyrrhiza uralensis is imperative and has a broad prospect. Licorice can be cultivated in semi-arid and arid areas with an average temperature of 4 ℃ ~ 12 ℃ and sunshine hours of more than 2600 hours. Selecting sandy or water soil with deep soil layer, pH value 7 to 8, groundwater level below two meters and soil salt content not more than 0.5% can achieve the purpose of high germination, high seedling preservation rate, fast growth rate, bright color and good quality of root and rhizome and high economic benefits. Barren farmland can also be good licorice.

Seed treatment

Licorice seed coat is solid, water permeability is poor, the germination rate is only 4%-6%, need to be broken skin treatment. The method of scraping the seed coat by rotating the central wheel of the vertical centrifugal rice mill is simple, efficient, safe, low cost and high germination rate; if the number of seeds is small, the seed coat can be corroded with concentrated sulfuric acid, and then washed with clean water, the seed coat can also be broken. Sowing seeds at the right time can be sowed from April to August, especially from April to May. In areas without irrigation conditions and heavy wind and sand in spring, sowing can be postponed to after June. Strip sowing is the best, with row spacing of 30 cm, sowing depth of 2 cm ~ 3 cm, deeper water and shallower clayey soil. Sowing in a small area can cover the soil, or sow seeds in trenches with a hoe. The planting mode of licorice is mainly direct seeding and seedling transplanting.

1. The seed purity of direct seeding is high and handled well, the soil texture is sand or sandy soil, the soil moisture is good, the sowing amount is 2 kg per 667 square meters (1 mu). The seed treatment is not good, the worm-eating rate is high, the soil texture is heavy or saline-alkali content is high, the sowing amount should be increased to 2.5 kg ~ 3 kg per 667 square meters. 20000 × 25000 seedlings are retained per 667 square meters, and the planting specification is 30 cm × 10 cm.

2. The cultivation and transplanting has irrigation condition and the soil texture is loam or sandy loam. More than 4000 kg of farm fertilizer and 40 kg ~ 50 kg of diammonium phosphate were applied to the treated high quality seeds every 667m2, 80000 seedlings were preserved and more than 60000 seedlings were transplanted. After a year of cultivation, when the root head of the seedling reaches 1 cm in diameter and 40 cm in length, you can come out of the nursery and dig out the seedlings before the land is frozen in that year or after thawing the following year. While digging and selecting, the seedling diameter (1 cm ~ 2 cm below the root) 0.8 cm ~ 1 cm and length 30 cm ~ 40 cm are selected and bundled, and the excess length is cut off. The slim dug up at the end of autumn chose a place with suitable temperature and humidity to plant in the leeward direction. The seedlings dug up in spring can be planted at the same time. Seedlings with insufficient thickness and length can be planted in another plot. Select the land with fertile soil and easy to irrigate, apply enough farm fertilizer and diammonium phosphate, and transplant in early April. According to the ditch spacing of 18 cm to 20 cm, the transplanting ditch with a width of 30 cm ~ 40 cm and a depth of 8 cm ~ 10 cm was opened manually or mechanically. The prepared licorice slim was discharged into the ditch horizontally according to the plant spacing of 8 cm ~ 10 cm and then covered with soil, and 10000 trees were transplanted every 667 m 2. In the first year of field management, the seedlings of direct seeding licorice grow slowly and are easily affected by weeds, so it is necessary to strengthen ploughing and weeding, weeding once at 3 leaves and 15 cm in height, every two years and the third year according to weeds and soil conditions. 2 times a year. Irrigate the soil moisture for 2 or 3 times. Licorice should be irrigated immediately after transplanting, and then irrigated, fertilized and pulled up in time depending on seedling emergence and weed growth. In order to prevent bumping and burying slim, do not loosen the soil.

Pest control

1. Licorice carmine scale is an important pest that affects the growth of licorice. Its harmful site is in the root of 5 cm ~ 10 cm under the soil surface, and the nymph sucks licorice juice, which weakens the growth of the aboveground part, so that the whole plant dries up and dies. The control method is to spray 1000 times of phoxim EC on the roots during the nymph incubation period (from the end of March to the beginning of April), and to spray 50% phoxim EC or 1000 times of phoxim on the ground during the peak emergence period of adults (early and middle August) to reduce the population density of the following year.

2. During the sprouting period of early spring and winter buds, the rust diseased plants were ditched and irrigated with 25% Fanning EC 667 m 2 (1 mu) 0.17 kg or Nongkang 120 water agent 20.8 kg per 667 m. It can also be sprayed on the roots of the diseased plants with 400 times solution of 97% diazosporin sodium. If the area is small or only sporadic, the diseased plants can burn the stems and leaves. The best time for harvesting direct sown licorice is 3 to 4 years old, and the best time for picking is from March to April. Generally, the yield of 667 square meters is 300 kg ~ 500 kg (fresh goods). The licorice seedlings and transplanting grow fast, and the yield of fresh grass at 667 m 2 can reach 600 kg to 1000 kg in the second year.