What are the latest propagation methods for Coptis chinensis?
Coptis chinensis, also known as Weilian, Chuanlian, Jizhualian, etc., is a perennial herbaceous plant of the genus Coptis in the Ranunculaceae family. It grows wild or is cultivated in cool, damp, shaded dense forests in valleys at an altitude of 1000-1900 m. It is a common traditional Chinese medicinal herb. Its propagation is mainly by seed, and it can also be propagated by division. Let us take a look together below!
Growing conditions for Coptis chinensis
Coptis chinensis prefers cool, humid, shaded conditions and avoids high temperatures and drought. It cannot withstand strong sunlight and prefers weak light; when the light is too strong, shading is needed. It is suitable for loose, fertile topsoil rich in humus with a deep soil layer. The most suitable pH is 5.5~6.5.
Division propagation of Coptis chinensis
Select 3-4 year old Coptis chinensis. Yalian (that is, Coptis deltoidea) has 3-4 branches per plant, while Weilian has 10-20 per plant. These branches can be separated from the rhizome. Select and keep seedlings with a rhizome length of 0.5-1 cm as division seedlings. Dig holes at a row spacing of 15×15 cm, with a hole depth of 6 cm, and plant 1 plant per hole. After planting, cover with fine fertile soil or humus soil, press firmly, plant straight, plant stably, and water thoroughly to settle the roots so as to promote survival. In the same year after planting, 70% of the plants will flower and set seed, and all will flower in the 2nd year. Division propagation has the advantages of fast growth, high yield of seeds and rhizomes, and good quality, and is worth promoting.
Seed propagation of Coptis chinensis
1. Seed selection and collection: Seeds set by 2-3 year old Coptis chinensis plants develop poorly and have a very low germination rate, so they are not suitable for seed use. Seeds set by 4-5 year old plants should be collected. In early May around the Beginning of Summer, when the follicles turn yellow-green and cracks appear but have not yet fully split open, harvest plump, full fruits in time.
2. Seed treatment: Coptis chinensis seeds are of the low-temperature type and have a relatively long dormancy period of more than 9 months. They need to go through a low-temperature stage to break dormancy and germinate. At the same time, once the seeds dry, they lose their germination ability. Therefore, wet sand stratification treatment must be carried out and they must be stored under low-temperature conditions to complete the post-embryonic ripening stage. For example, first cut off the fruits that are about to split together with the fruit stalk, and spread them indoors in a ventilated and cool place to after-ripen for 2~3 days. After the follicles split, beat out the seeds, winnow away impurities, and blow away shriveled seeds. Then, mix the seeds evenly with 3 parts moist fine sandy soil, put them into a wooden box, and store them in a cave. If there are only a small number of seeds, they can be put fresh into a refrigerator and stored at a low temperature of 0-6 degrees C for 180 days, and the germination rate can reach more than 90%.
3. Sowing method: It is best to sow in autumn from October to November. For broadcast sowing, thoroughly and evenly mix fresh-preserved seeds with 20 times their amount of sieved fine humus soil and broadcast it on the seedbed surface. It should be sown evenly. After sowing, press slightly with a wooden board so that the seeds are in close contact with the soil, then spread a layer of finely crushed manure soil 0.5-0.7 cm thick, to the extent that the seeds are not visible. Finally, thinly cover the seedbed surface with a layer of rice straw to keep warm and moist so as to promote emergence. Remove it after the temperature rises in early spring of the following year. The seeding rate is 3-4 kg per mu, which can raise more than 500,000 seedlings.
4. Seedling management
1) Build a shed: After sowing, build a low shed over each seedbed, 50-70 cm high. Local materials can be used. Set up posts and crossbars on both sides of the seedbed, and cover the top with shading materials such as small bamboo poles, branches and leaves, so that the shade density in the shed is evenly distributed at about 80%. Using low sheds for seedling raising saves labor and materials, and can also reduce rainwater erosion of the seedbed, which is beneficial to the growth of Coptis seedlings.
2) Thinning: In March to April, when the seedlings grow 2 true leaves, carry out thinning, remove the weak and keep the strong, and maintain a plant spacing of about 1 cm.
3) Topdressing and earthing up: After thinning, apply 1000 kg of light human and livestock manure water per mu, or sprinkle 3 kg of urea mixed with 1000 kg of water. In June to July, apply the above fertilizer 1 more time. After application, spread a layer of fine humus soil about 1 cm thick around the seedling roots to stabilize the seedlings. In August to September, apply 50 kg of cake fertilizer powder mixed evenly with 250 kg of fine humus soil and sprinkle it on the seedbed surface. In spring of the 2nd year, from March to April, apply 1 more round of light manure water, or sprinkle 3 kg of urea mixed with 1000 kg of water, with very good results.