Cultivation techniques of Radix Astragali

Astragalus mongolicus, also known as Astragalus membranaceus, perennial herbs, 40-150 cm high or slightly over, the main root is straight, cylindrical, 25-75 cm long, slightly woody, the root head is 1.5-3 cm straight, and the epidermis is light brownish yellow or dark brown. Stem erect, much branched, villous. Leaves odd-pinnate, alternate; petiole base has lanceolate stipules, about 6 mm long; leaflets 25-37, leaflets broadly elliptic, 4-9 mm long, apex slightly obtuse, mucronate, base cuneate, entire, white villous on both surfaces. Racemes axillary, with 10-25 flowers, loosely arranged; pedicels short, black hirsute; bracts linear-lanceolate; calyx tubular, ca. 5 mm, calyx teeth 5, villous; Corolla yellow, butterfly, less than 2 cm long, flag petals triangular-Obovate, unclawed, apex retuse, pterygoid and Yougu petals all have long claws; stamens 10, disomic; ovary stalked, smooth glabrous, style glabrous. Pods membranous, inflated, ovate-orchard, 11-15 mm wide, apex beaked, distinctly reticulate. Seeds 5-6, reniform, black. The flowering period is from June to July and the fruiting period is from August to September.

Planting techniques of Radix Astragali

Radix Astragali is a perennial herb of Leguminosae. The dried root is used as medicine, and the medicinal name is Astragalus membranaceus, which has the functions of replenishing qi and solidifying the surface, diuresis, removing poison and expelling pus, and producing muscle.

1 Botanical characteristics and environmental requirements

1.1 Botanical characteristics

The main root is long and stout, the stem is erect, and the 40~80cm is high. Leaves odd-pinnate, leaflets 12-18 pairs; leaflets broadly elliptic, elliptic or oblong, shortly pedicellate, leaves long 5~10mm, broadly 3~5mm, both ends subrounded, upper glabrous, lower pilose; stipules lanceolate. Racemes axillary, with 5 × 20 flowers; calyx campanulate, densely pubescent, with 5 calyx teeth; Corolla discoid, yellow to yellowish, long 18~20mm, flag oblong-Obovate, pterygoid and keel with long claws; 2-body stamens; ovary smooth glabrous, pods membranous, swollen, semiovoid, apex shortly beaked, base with long ovary stalk, all glabrous. The florescence is from June to July and the fruiting period is from July to September.

1.2 Environmental requirements

Like sunshine, drought, waterlogging, cool climate, cold resistance, can withstand low temperature below-30 ℃, afraid of heat, strong adaptability. Most of them grow on the arid sunny grassland or among the trees on the edge of the sunny forest in the mountainous or semi-mountainous area at an altitude of 800m to 1300m above sea level; the vegetation is mostly coniferous and broad-leaved mixed forest or mountain mixed forest; the soil is mostly mountain forest soil. Avoid continuous cropping, not with potatoes, chrysanthemums, Atractylodes macrocephala and other continuous cropping.

2 cultivation

2.1 Land selection and preparation

Astragalus mongolicus is a deep-rooted plant, flat cultivation should choose high-lying, well-drained, loose and fertile sandy loam, and mountain areas should choose slopes or wasteland with deep soil layer, good drainage and leeward to the sun. After selecting the land for soil preparation, it is better to turn the land in autumn. General ploughing depth 30~45cm, combined with ploughing soil base fertilizer, farm manure 2000~2500kg, superphosphate 25kg / mu; spring ploughing should pay attention to soil moisture conservation, then rake fine leveling, make ridges, general ridge width 40~45cm, high 15~20cm.

2.2 seed treatment

2.2.1 soak the seeds in warm soup after spring rain, immediately put the seeds in a container, add proper amount of boiling water and keep stirring for about 1 minute, then add cold water to adjust the water temperature to 40 ℃, place for 2 hours, pour out the water, stew the seeds with mulch for 8 hours and 10 hours, wait for the seeds to expand or the outer skin is broken, sow the seeds after the rain.

2.2.2 the dry seeds are mixed with the dry fine sand with a seed volume of 2ppm and pressed on a stone mill, and the seeds can be sown when the seed is crushed until the outer skin changes from brown-black to grayish brown. The combination of the two methods in production is better.

2.3 seed direct broadcast

It can be sown in spring, summer and autumn. In spring, the seeds can be sowed when the soil temperature reaches 5: 8 ℃, keep the soil moist, and seedlings can emerge in about 14 days, while summer sowing is carried out when the rainy season comes from June to July. If the soil moisture is sufficient and the temperature is high, seedlings can emerge 7-8 days after sowing, and autumn sowing is carried out when the soil temperature is stable at 1-6 ℃.

The sowing method is strip sowing or hole sowing. The row spacing of strip sowing is about 20cm, the furrow depth is 3cm, and the sowing rate is 2~2.5kg per mu. When sowing, the seeds were mixed with methamidophos or pyrethroids pesticides to control underground pests, and the soil was covered with 1.5~2cm after sowing. Diammonium phosphate 8~10kg and potassium sulfate 5~7kg were applied per mu. Keep the soil moist or add mulch from sowing to seedling emergence to promote seedling emergence. Most of the acupoints were sown according to the distance between 20~25cm acupoints, and 5-10 seeds were planted at each point, and 1.5cm was covered with soil, and the sowing rate was 1kg per mu.

2.4 Field management

2.4.1 seedlings and fixed seedlings were carried out when the seedling height was 6~10cm, and 5 after the appearance of compound leaves. When the seedling height is 15~20cm, the seedling is fixed according to the plant distance 20~30cm. The seedlings planted in holes were fixed according to 1 / 2 seedlings per hole.

2.4.2 loosening soil and weeding can be carried out for the first time when the seedlings come out. At this time, the small root of the seedling is shallow, which should be dominated by a shallow hoe. After that, weeding 2 or 3 times according to the condition of the field.

2.4.3 nitrogen and phosphorus fertilizers should be applied after topdressing seedlings, generally applying ammonium sulfate 15~17kg or urea 10~12kg, potassium sulfate 7~8kg and calcium superphosphate 10kg per mu. At flowering stage, calcium superphosphate 6~10kg and nitrogen fertilizer 7~10kg were applied per mu to promote fruiting and seed maturity. The land with fertile soil should apply less chemical fertilizer as much as possible.

2.4.4 Irrigation and drainage "like water but afraid of water", and pay attention to "irrigation and drainage" in management. It has two peak periods of water demand, namely, seed germination and flowering and podding. Irrigation at the seedling stage needs a small amount of irrigation, and appropriate watering is needed at the flowering and podding stage. Drainage should be paid attention to at all times during the rainy season.

3. Harvesting and processing

3.1 harvesting

The quality of 3 ~ 4 years old is the best. At present, it is generally mined in 1 ~ 2 years, which affects the quality of medicinal materials, and it is recommended to dig for 3 years. In order to dig in the dormant period and germination period, the content of astragaloside in Astragalus mongholicus is higher, so it should be harvested in late April and early May and late October and early November. When harvesting, you can first cut off the ground part, and then dig out the root. Be careful not to cut off the roots, so as not to affect the yield and quality.

3.2 processing

Will dig out the root, remove the soil, sun to 70% to 80% dry to remove the lateral root and fibrous root, grade into small bundles and then dry. The root strip is stout, the surface is light yellow, the cross section is white, the middle is light yellow and the taste is sweet, and the dry products are stored in a ventilated and dry place.