High-yielding cultivation methods of Radix Isatidis

Radix Isatidis is a perennial cruciferous plant, its roots and leaves can be used medicinally, it is commonly used as a large variety of traditional Chinese medicine, and it is also one of the first choice of antiviral traditional Chinese medicine. The plant has strong adaptability, likes warm and sunny environment, and is cold-tolerant. It can be planted in the north and south of our country except low-lying waterlogged land and heavy clay soil. The high-yield cultivation techniques of this medicinal material are introduced as follows:

1. Soil preparation and fertilization

Because Radix Isatidis is a deep-rooted plant, it is appropriate to choose a flat, well-drained, fertile and loose sandy loam. Combined with soil preparation, each mu should be treated with rotten compost or barnyard manure 2000 kg / mu, plant ash 100 kg, calcium superphosphate 20 kg / mu, or compound fertilizer 50 kg, turning more than 30 cm deep, shallow ploughing once, raking fine and leveling to make a flat bed 1 to 1.5 meters wide. In case of drought, it should be watered to make moisture before sowing.

Second, sowing seeds at the right time

Spring sowing is divided into summer sowing. Spring sowing is in the first and middle of April and summer sowing is in late May. Spring sowing should not be premature, because the seeds will go through the vernalization stage, bolting and flowering ahead of time due to the influence of early spring cold after emergence, which leads to planting failure. Soak the seeds in 30 ℃ ~ 40 ℃ warm water for 4 hours before sowing. Fish it out to dry. Strip sowing and hole sowing can be done. Strip sowing method is often used to trench the border according to the row spacing of 20 cm to 30 cm and the ditch depth to 1.5 cm. The seeds mixed with fine sand are evenly scattered into the ditch, and the soil is pressed after covering 0.5 cm to 1 cm to keep the border soil moist. When the temperature is 18 ℃ ~ 20 ℃, seedlings can emerge in 10 days, and the row spacing of hole sowing can be 25 cm. The germination rate of Radix Isatidis seeds is 80%, with 4 kg of seeds per mu, sowing seedlings is poor, thus affecting the yield.

III. Field management

1. Miao. Seedling height 5 cm 7 cm time seedling, seedling height 10 cm 15 cm fixed seedling, inter-seedling and fixed seedling should be weak and strong, replenish seedlings in time, and keep the soil moist at this stage.

two。 Ploughing and weeding. After finishing the seedlings, one time should be ploughed and weeded in time, and then once every half a month or so. After the plants are closed, the weeding should not be carried out.

3. Top dressing. From May to July, 500 kilograms of human feces and urine or 10 kilograms of urea were applied per mu, and 10 kilograms of superphosphate was added and watered after application. Apply 5kg of ammonium sulfate per mu after each leaf harvest (do not use ammonium bicarbonate).

4. Water and drain. It should be watered in time when the summer weather is dry, and pay attention to ditch drainage in the rainy season to prevent rotting roots.

5. The method of reproduction. When propagated with seeds, Radix Isatidis harvested but did not bear seeds in that year. When planing and harvesting Radix Isatidis in late October, select the root strips that are disease-free, sturdy and non-branching of the main root, transplant to the fertile seed field according to the row spacing of 50 cm × 30 cm, water in time after planting, and strengthen field management; the seeds are harvested, dried and threshed in stages from May to June in the second year, and stored in a ventilated and dry place, the roots of Radix Isatidis that have been harvested can no longer be used as medicinal materials.

IV. Pest control

1. Disease. There are mainly downy mildew and root rot. Downy mildew leaves showed light green disease spots, white or gray mildew was produced on the back of the leaves, and died in severe cases; root rot mostly occurred in the rainy season, resulting in root rot, resulting in the death of the whole plant. Prevention and control methods: give priority to agricultural control, reasonable rotation and close planting with Gramineae and leguminous plants, improve ventilation and light transmission conditions, and find diseased leaf disease plants removed out of the field in time, concentrated and buried deeply; 65% zinc or 77% can also be sprayed or irrigated with wettable powder.

two。 Pests. There are mainly cabbage worm and diamondback moth. Plutella xylostella bites leaves, causing holes and holes in the leaves, leaving only veins in serious cases; Plutella xylostella bites leaves, causing "skylight" at the initial stage, and holes and holes in the later stage, leaving only reticular veins. Diflubenzuron 3, BT emulsion and 1000-fold spray were used to control trichlorfon.

V. harvesting and processing

1. Daqingye. Spring sowing is harvested 2 to 3 times a year, the first in early June and the second in early August, but it is not suitable to harvest in the hot season in summer, so as not to cause the death of plants. The third harvest is from mid-October to before digging roots. When harvesting, you should choose a sunny day, the knife edge is 1cm away from the ground, pick out the withered and yellow leaves and impurities after cutting, dry them immediately, and avoid stacking them in the drying process, so as not to heat, blacken and deteriorate the leaves. About 200 kilograms of dried leaves are produced per mu and placed in a ventilated and dry place after drying to prevent mildew.

two。 Radix Isatidis. Digging roots in late October, because the roots are deep in the soil, we should first dig deep ditches at one end of the border and dig along the ditches to avoid breaking the roots, remove the stems, leaves and soil on the ground, dry them into small bundles, and then dry them to the whole dry, and put them in a dry place to prevent mildew, producing 200 kilograms of finished Radix Isatidis per mu.