Breeding and Pest Control Cultivation Techniques of Baikal Root

Propagation and Pest Control and cultivation techniques of Scutellaria baicalensis Georgi

1 morphological characteristics

Scutellaria baicalensis Georgi is a perennial herb with branched roots, several stems clustered on one root, long and thick, cylindrical, solid in the new root, hollow in the old root, dark yellow in the inside and dark brown in the outer skin. The whole plant is 30mm 30 (50) cm tall, the stem is pinstriate, obtusely four fusiform, curved up to spreading puberulent or glabrous, often purplish or green. Leaves alternate, sessile, leaf blade orbicular to linear-lanceolate, 1.5-3.5 cm long and 3-9 (13) mm wide, entire, base subrounded, apex obtuse, surface puberulent or glabrous, dark green, abaxially pilose along midvein, light green, densely black sunken glandular spots. Racemes terminal or axillary, 7-15 cm long, inclined to one side; bracts subglabrous, 7-12 mm long, leafy, ovoid-lanceolate to lanceolate; calyx purplish green, 2-lipped, with peltate appendages on the back of the upper lip, enlarged when fruiting, membranous Corolla purplish red or blue-purple, 2-lipped, upper lip emarginate, helmet-shaped, lower lip 7.5 mm wide, middle lobe triangular-ovoid, bilateral lobes close to upper lip, Corolla tube slender, base curving; stamens 4, slightly exserted; ovary 4, glabrous, born on annular disk, brown, parted; style slender, apex lobed. Nutlets 4, black, ovoid, 1 mm in diameter, 1.5 mm long. The florescence is 7 Mel in August and the fruiting period is 8 mi in September.

2. Habitat distribution

The total annual radiation of Scutellaria baicalensis Georgi is 459.8-564.3 kJ/cm2, and 501.6 kJ/cm2 is suitable for its growth. It is more resistant to barren and suitable for growing in deep and fertile neutral and slightly alkaline loam or sandy loam environment, and soil pH 7 or slightly greater than 7 is suitable. The most suitable annual average temperature is 2: 4 ℃, cold-tolerant, the underground part of its adult plant can survive the winter safely at-35 ℃, 35 ℃ will not die, but can not withstand a continuous high temperature of more than 40 ℃, it is more drought-tolerant, and the annual precipitation of 400 mm can grow normally. Shady wetlands are rare in mid-temperate mountain forests, commonly distributed on plateau grasslands or sunny slopes at an altitude of 600 to 1 500 m above sea level, and are often associated with some weeds in the central distribution area, such as Artemisia, Gramineae weeds and so on.

Wild Scutellaria baicalensis Georgi resources are widely distributed in China, growing in the range of 110 °E 130 °E and 34 °N 57 °N, mainly concentrated in Shaanxi, Shanxi, Hebei, Liaoning, Jilin and other provinces of North China. The reserves of wild resources in China are about 150,000 tons, including Wutai in Shanxi, Shide, Arqin and other 27 county flags in Inner Mongolia, Longhua, paddock, Fengning and Chicheng in Hebei Province. Bashang area of Hebei Province is the main producing area of authentic Scutellaria baicalensis, known as "rehe Scutellaria baicalensis"; 500,000t is Durbert Mongolian Autonomous County in Heilongjiang Province and Zhalantun in Inner Mongolia. 1 000 to 5 000 tons are Yakeshi in Inner Mongolia, Oroqen Banner, Ergunazuo Banner and other places.

3 cultivation techniques

3.1 Land selection and preparation

In view of the habit that Scutellaria baicalensis Georgi is afraid of waterlogging and likes light, we should choose sandy loam or light chestnut soil with sufficient light, no tree shading, leeward to the sun, high and dry terrain, low groundwater level, good drainage, loose soil, deep soil layer and rich in humus. In the determined plot, 450 kg/hm2 calcium superphosphate, 75 t/hm2 high quality and mature farm manure and proper amount of potassium fertilizer were used as base fertilizer. The deep ploughed land was ploughed for 25 cm, raked finely and then made into a flat bed with a width of 1.2m for sowing.

3.2 seed propagation

3.2.1 seed selection. As the florescence of Scutellaria baicalensis Georgi is as long as 2-3 months, the seed ripening period is very inconsistent, and it is easy to fall off, so it needs to be harvested with ripening. Finally, the seeds can be cut off with fruit branches, sun-dried and harvested to remove impurities. In order to reduce the harm of diseases, pests and weeds in the field, high-quality seeds should be selected for sowing, and such seeds have high germination rate, strong germination potential, neat growth and easy management. The specific seed selection criteria are: excellent characteristics of the original variety, uniform size, full grain, bright color, no diseases and insect pests.

3.2.2 seed direct seeding. The sowing time should be for the purpose of achieving the whole seedling and be properly controlled according to the local conditions. Generally, spring sowing is carried out in May in April, summer sowing in August in July in the rainy season (suitable for places without irrigation conditions), and winter sowing in October. Generally, strip sowing is used, and a shallow trench with a depth of 2 cm and 3 cm is opened according to the row spacing of 25: 30 cm. The seeds are evenly sown in the ditch, covered with soil for about 1 cm, and gently pressed after sowing. Because the seeds of Scutellaria baicalensis Georgi are small, in order to sow evenly, it can be mixed with 5-10 times fine sand and then mixed, and the sowing rate is 7.5-11.25 kg/hm2. Seedlings emerge after sowing for 5-7 days in the rainy season, and seedlings can emerge in about 15 days if the soil moisture is moderate in other periods.

When preparing the soil, the soil must be ploughed and raked deeply, and the soil is fine. This is because the covering soil should not be too thick when sowing, and the seedlings often appear incomplete because of uneven surface soil or soil drought, resulting in continuous lack of seedlings and ridges. If there is drought during sowing, the soil should be watered in time after sowing, and the soil should always be kept moist before and after seedling emergence for a period of time. In order to shorten the time of seedling emergence, the best germination treatment should be carried out during sowing (soaking the seeds in warm water of 40-45 ℃ for 5-6 h, then thinly spreading them on a wooden budding plate covered with double-layer skimmed gauze, washing with clean water twice a day for moisturizing under the condition of 20-25 ℃, and then sowing most of the seeds after the germ germinated). As the budding seedlings are fragile, they should be sowed in soil with good soil moisture to resist drought and protect seedlings. Spring sowing in arid areas can be covered with plastic film to retain moisture and preserve soil moisture. The method of raising seedlings in nursery and transplanting in field is suitable for some particularly arid slopes.

3.2.3 Seedling and transplanting. Generally, the ratio of field transplanting area to seedling area is 5 ∶ 1. In late April, the leeward and sunny plot was selected as the nursery for sowing, the amount of seed was 22.5 kg/hm2; after emergence and time seedlings, the plant spacing was about 5 cm, strengthen fertilizer and water management, pay attention to moisture and heat preservation, and immediately transplant to the field after soil thawing in the next spring, with a row spacing of 9 cm × 18 cm.

3.3 Cuttage propagation

The Scutellaria baicalensis Georgi planted by cutting seedling method has high yield and good quality, and the selection of breeding season and cutting position are the key factors for the success or failure of cutting propagation. The cuttings of Scutellaria baicalensis can be carried out in spring, summer and autumn, but the survival rate of cuttings is higher in May and June in spring. The survival seedlings are transplanted in the rainy season and large seedlings are formed before entering winter, which can survive the winter safely. Cuttings can not use the middle and lower part of the stem, should choose any treatment of the stem tip semi-lignified tender part, the survival rate can reach more than 90%. When cutting, sand, sandy loam or sand mixed with vermiculite is used as substrate and cut into the prepared seedling bed according to the row spacing of 10 cm × 5 cm. The long and tender stems of 6 cm at the end of the stem are cut as cuttings, the leaves of the following 2 sections are removed and 3 leaves are reserved. The best time for cutting is cloudy days, and cutting before 10:00 or after 4:00 in sunny days is appropriate. In order to keep the cuttings fresh, they should be cut and watered every morning and evening after cutting, but in order to avoid causing cuttings to rot, the amount of water should not be too large; a shading shed with a canopy of 50% to 80% should be built to improve the survival rate; it can be transplanted to the field 40-50 days after cutting, and the suitable row spacing is 15 cm × 30 cm.

3.4 ramet propagation

Ramet propagation not only has the advantages of fast growth and short production cycle, but also has a high survival rate. The high-yield and high-quality plants were selected during harvest, the root head was cut off for propagation, and the main root was reserved for medicinal use. It can be planted as it is dug in spring, and the harvested roots can be buried in the cellar for the winter, and then split in the following spring. When dividing a plant, the root head can be split into several individual plants according to its natural shape, leaving 3 or 4 bud holes on each single plant, and then planted in the field according to the row spacing of 20 cm × 30 cm, so as to improve the propagation coefficient.

4 field management

4.1 fixed seedlings

After emergence, it is necessary to remove the weak seedlings from time to time. When the seedling height is 6-7 cm, the seedlings should be fixed according to the plant distance of 12-15 cm, and replenish the seedlings where the seedlings are missing. The overdense seedlings can be transferred to replenish the seedlings, and the replanting should be carried out in cloudy days or in the afternoon. Be sure to transplant with dirt and water after planting.

4.2 ploughing

It needs to be ploughed for 2 to 3 times in spring, and shallow ploughing should be needed so as not to hurt the medicinal root.

4.3 topdressing

The first topdressing was carried out after setting seedlings, 7.5 t/hm2 of rare human feces and urine, 450 kg/hm2 diammonium phosphate in July, 7.5-15.0 t/hm2 of human feces and urine in the second and third years after turning green and before closure (late June) respectively, and foliar spray fertilization was carried out in sunny days with potassium dihydrogen phosphate for 9 kg/hm2 in three times.

4.4 drainage and irrigation

Scutellaria baicalensis Georgi is drought-resistant and does not need watering except in case of persistent drought. In the rainy season, stagnant water in the field should be eliminated in time to prevent dead seedlings from rotting roots and reduce quality and yield.

(5) Disease and pest control

5.1 Diseases

5.1.1 Leaf blight. The pathogen is a semi-known fungus that damages leaves. The disease occurs frequently and seriously in rainy and high temperature season. It extends inward from leaf tip or leaf edge to irregular dark brown disease spot, spreads rapidly from bottom to top, and finally leaves die. The spot film occurred at the beginning, and it can spread to the whole field if it is not prevented in time. The source of overwintering bacteria should be eliminated in winter, and the disease residue in the field should be treated. 1 ∶ 120 Bordeaux solution or 50% carbendazim wettable powder 1000 times solution should be sprayed at the initial stage of the disease.

5.1.2 powdery mildew. High humidity in the field can easily lead to the occurrence of powdery mildew. The disease mainly infects the leaves, with white powdery spots on both sides of the leaves, gradually converging and covering the whole leaf, and finally small black particles scattered on the disease spots. Field management should be strengthened for prevention and control. 0.1%-0.2% wettable sulfur powder or 50% Dysenamine 1000-fold solution can be sprayed.

5.2 main pest-Scutellaria baicalensis

As an important pest of Scutellaria baicalensis, Scutellaria baicalensis overwinters as pupae on the remnant leaves, the larvae make thin silk nests on the back of the leaves, and the worms feed on the mesophyll in the silk nests, leaving only the epidermis. First of all, the garden should be cleared for prevention and control, and 90% crystal trichlorfon 800 times liquid should be sprayed during the occurrence period.

6. Harvesting, processing and storage of Scutellaria baicalensis

6.1 harvesting and processing

Scutellaria baicalensis Georgi can be harvested after growing for 2-3 years. Because the content of baicalin in fresh and dry roots of 3-year-old is higher than that of 2-year-old, and the content of baicalin is the highest after defoliation in autumn, it is generally the best harvest time after the aboveground withered in autumn. The root system of Scutellaria baicalensis Georgi is deep and long, and it needs to be dug deeply during harvest to avoid cutting off the root; remove the residual stem, sun until semi-dry, peel off the skin, tie it into small handfuls, and continue to dry or dry. Because Scutellaria baicalensis turns green when exposed to water and turns red if it is exposed to excessive sun exposure, so in the process of drying, it is necessary not only to prevent wet rain, but also to avoid excessive exposure to the sun to ensure quality.

6.2 Storage

Scutellaria baicalensis Georgi is generally stored in a dry and ventilated place of about 30 ℃ by stack or piece by piece, with a safe moisture content of 11% 13% and a relative humidity of 70% and 75%. Scutellaria baicalensis Georgi is easy to be eaten or discolored by moisture in summer high temperature season. Once damp or mildew is found, it should be ventilated, turned and dried in time. It can also be cured with CO2 or N2 in the closed warehouse, which can not only prevent mildew and insect pests, but also have no obvious effect on the composition of Scutellaria baicalensis. In addition, it was found that the mold content of Piper longum volatile oil fumigated with 10000 ∶ 1 volatile oil for 6 days was greatly reduced, which indicated that fumigation and anti-mildew with volatile oil from Piper longum eggplant had the advantages of economy, practicality and no residual poison.

7 Market analysis

As one of the large varieties of traditional Chinese medicine commonly used in China, Scutellaria baicalensis has a long history of application and has a great demand [3]. It is not only used as a TCM formula for analgesia and anti-inflammation, purging fire and clearing heat, but also widely used as raw materials for proprietary Chinese medicine industry. its extracts baicalin and baicalein as pharmaceutical raw materials have opened up a new way for the further development and utilization of Scutellaria baicalensis. The famous Chinese patent medicine Shuanghuanglian series preparations are produced with Shuanghua, Scutellaria baicalensis and Forsythia suspensa as raw materials, and Qinbaohong series products with Scutellaria baicalensis, Scutellaria baicalensis and Manshanghong as raw materials have also become famous products at home and abroad.

The growing social demand has strongly stimulated the development of Scutellaria baicalensis market. According to statistics, in the 1950s and 1960s, the purchase and sales of Scutellaria baicalensis increased from 3 million kg;70 in 20 million to 4 million kg;1983 in 4 million. The purchase volume of Scutellaria baicalensis increased sharply to 2 1 million kg, and the sales increased to 8 million kg. In the 1990s, the price of Scutellaria baicalensis Georgi has been maintained at 1215 yuan / kg, and has shown an upward trend in recent years. The commodity of Scutellaria baicalensis in China mainly comes from wild resources, but after long-term predatory mining, especially the over-purchase in 1983, most of the mountain and grassland Scutellaria baicalensis were excavated, and the resources of Scutellaria baicalensis Georgi in most areas were on the verge of extinction. Most of the remaining wild resources are in remote areas, with inconvenient transportation, poor conditions, sparsely populated and difficult to dig. In addition, in the past decade, the northern region has been dry and little rain, and the recovery of wild resources is slow. Moreover, due to the high profits of Scutellaria baicalensis, wild resources are still being excavated, continue to shrink, and product quality continues to decline.

The unoptimistic market supply creates good conditions for the development of Scutellaria baicalensis production. We should seize the opportunity to establish Scutellaria baicalensis Wild Resources Reserve in authentic producing areas, gradually restore the wild Scutellaria baicalensis community, and mainly take measures of artificial planting and wild growth. We should conscientiously implement the policy of both mining, protection and cultivation, and plan to harvest while planting. After several years of less mining, diversity and more cultivation, the resources of Scutellaria baicalensis Georgi have formed a dynamic balance and entered the track of virtuous circle and sustainable development. In addition, we should popularize and apply high-yield and high-quality cultivation techniques to guide the production of Scutellaria baicalensis, establish artificial planting bases, and select excellent varieties, so as to improve the yield and quality of Scutellaria baicalensis, create higher economic benefits for drug farmers, and meet the needs of domestic and foreign markets.