How are Bupleurum seeds planted? A detailed introduction to the planting method
Bupleurum is a medicinal herb included in the Pharmacopoeia of the People's Republic of China, also known as Di Xun, Shan Cai, Gu Cao, etc. The medicinal part is the dried root of the Umbelliferae plant Bupleurum chinense or Bupleurum scorzonerifolium. It prefers a warm and humid climate, is cold-tolerant, drought-tolerant and afraid of waterlogging, and is suitable for planting in deep, fertile sandy loam soil. In production, either seed propagation or seedling transplanting can be used. Let's take a look below at how Bupleurum seeds are planted!
How are Bupleurum seeds collected?
1. Selecting plants for seed: Choose robust 2-year-old Bupleurum plants free of pests and diseases to keep for seed. Do not remove the bolting stems or tillers from the retained Bupleurum plants, and remove all tillers and bolting stems from the plants not kept for seed. For the seed plants, apply extra phosphorus and potassium fertilizer in field management.
2. Spraying foliar fertilizer: During the flowering and bud stage, potassium dihydrogen phosphate can be sprayed on the leaves at a concentration of 0.2-0.3%, once every 5 days for 2 consecutive times, which can promote fruit development and plump seeds.
3. Collection and storage: From September to November, when the fruits turn from green to brown, collect the upper seed-bearing parts together with the branches and stalks, air-dry them in a ventilated and dry place, then thresh and sun-dry, winnow out the plump and mature seeds, and store them sealed in jars or earthenware pots for later use.
How are Bupleurum seeds treated?
1. Chemical treatment: Soak the seeds in a 0.8-1.0% potassium permanganate solution for 10-15 minutes, which can increase the emergence rate by 15.4%.
2. Hormone treatment: Soak the seeds in 0.5x10-6-1.0x10-6 cytokinin (6-8A) for 1 day, take out the seeds, rinse them clean with water, and then sow, which can increase the seed emergence rate by 12.6%.
3. Warm water and sand stratification: Soak the seeds in warm water at 35-40°C for 1 day, remove the shriveled seeds floating on the water surface, then mix 1 part seeds with 3 parts wet sand and place them at 20-25°C to promote germination. After about 10-12 days, when some seeds have cracked open, sow to ensure a sufficient number of seedlings.
How are Bupleurum seeds planted?
1. Land selection and preparation: For Bupleurum, choose loam and sandy loam or gentle sloping land with deep, loose, fertile soil and good drainage. Before planting, plow and harrow several times, apply 30,000 kg/ha of decomposed barnyard manure, and build raised beds 120-130 cm wide, 25 cm deep, and 30 cm wide for sowing.
2. Ditching and sowing: Before sowing Bupleurum, open horizontal ditches 10 cm deep on the prepared bed surface at 20 cm row spacing, then sow at 15 cm hill spacing or in drills. Spring sowing is from early April to early May, and autumn sowing is from after the seeds are dried after ripening to before the soil freezes in early November.
3. Timely thinning: Bupleurum emerges 12-15 days after sowing. When the seedlings reach 4-5 cm, carry out the first thinning, removing overly dense seedlings and weak, diseased seedlings. When the seedlings reach 8-10 cm in height, carry out final thinning, with a suitable final stand of 675,000-825,000 plants/ha.
4. Replanting and weeding: If there are missing plants in the Bupleurum field, they should be replanted, and the replanted seedlings should be watered promptly. After the plants close the rows, no more intertillage is carried out; only hand pulling of weeds is done to avoid root damage and yield reduction. Generally, chemical herbicides are not used for weeding.
5. Reasonable fertilization: During the growth period of Bupleurum, topdressing should be applied multiple times. The first seedling fertilizer is applied at the first thinning together with intertillage and weeding, the second seedling fertilizer is applied at final thinning together with intertillage and weeding, and the third topdressing is applied when the seedlings are 30-40 cm tall. For a separate potassium supplement, organic potassium fertilizer can be sprayed on the leaves.
6. Clearing ditches and draining moisture: Bupleurum likes to grow in a humid environment, but it is most afraid of water accumulation and soaking in the field. Before the rainy season arrives, the bed ditches should be cleared in time to ensure smooth drainage in the bed ditches and reduce the occurrence of field diseases.
7. Removing tillers and bolting stems: The aboveground part of Bupleurum grows vigorously. Half of the first-year plants can bolt and flower, and all second-year plants can bolt and flower. Removing tillers and newly grown flower bolting stems and buds in a timely manner in several rounds can promote the accumulation and expansion of nutrients in the plant roots.
8. Pest and disease control: For pest and disease control in Bupleurum, follow the principle of not applying heavy-metal pesticides or highly toxic, high-residue pesticides, insist on giving priority to agricultural preventive measures, and adopt control methods using biological pesticide formulations or high-efficiency, low-toxicity pesticides.