Detailed Guide to Pollution-Free Production Techniques for Bupleurum

Bupleurum: Bupleurum is the root of the Apiaceae plant Bupleurum chinense DC. The taste of Bupleurum is bitter and pungent, with a slightly cold nature. It enters the Liver and Gallbladder meridians. It has the functions of dispersing and reducing fever, soothing the liver and relieving depression, and raising yang and lifting prolapse, and is mainly used for cold and fever, alternating chills and fever, chest and hypochondriac distention and pain, irregular menstruation, uterine prolapse, rectal prolapse and other conditions.

Suitable growing conditions for Bupleurum. Bupleurum prefers a warm and humid climate and is suitable for growing at an altitude of 600 m to 800 m in shallow mountain areas on relatively dry hillsides, forest edges, gaps in forests, grassy areas and beside ditches. It has strong cold resistance, is drought-resistant, and fears waterlogging. The ideal soils are loam, sandy loam or humus soil. Selection of a Bupleurum planting base. Establishing a Bupleurum production and planting base must be in the most suitable area for Bupleurum growth and must have environmental conditions compatible with it. According to GAP requirements, the atmospheric environment should conform to the GB 3095—2012 "Ambient Air Quality Standard"; soil environmental conditions should conform to the GB 15618—1995 "Soil Environmental Quality Standard"; and irrigation water should conform to the GB 5084—2005 "Irrigation Water Quality Standard for Farmland". It should be far from main roads and pollution sources, with convenient transportation, and cultivated on hillside fields with sandy loam or humus soil. Clay and areas prone to water accumulation are not suitable for planting. If sowing on reclaimed wasteland, stones, branches and other debris in the field should be cleared away.

I. Planting management

1.1 Site selection and land preparation. Select a sandy loam plot with good drainage. Apply 2000 kg to 3000 kg of fully decomposed farmyard manure per 667 sq m, or apply 70 kg of fermentation bacterial biological fertilizer. Spread the base fertilizer evenly, turn it into the soil, then deep plow and harrow finely.

1.2 Variety selection and requirements. Use the Apiaceae plant Bupleurum chinense DC. recorded in the "Chinese Pharmacopoeia" as the species source, and select seeds with plump grains and a germination rate of not less than 70%.

1.3 Sowing

1.3.1 Sowing period. Spring sowing is carried out in mid-March, before Qingming; autumn sowing is carried out around Frost's Descent.

1.3.2 Sowing method. Open furrows at a row spacing of 20 cm, with a furrow depth of 1.5 cm to 2 cm, evenly scatter the seeds into the furrows, then cover with soil 1 cm to 2 cm deep, and lightly compact. The sowing rate per 667 sq m is 1.5 kg to 2.0 kg.

1.4 Field management

1.4.1 Mulch. For spring and autumn sowing, choose wheat straw or thatch grass for mulching, with mulching to the extent that the soil is not exposed, then press branches on top. After sowing, inspect once every 5 d to observe soil moisture. If dry, spray water on the mulch. After seedlings emerge, gradually remove the mulch multiple times on cloudy days or in the evening on sunny days.

1.4.2 Thinning to a stand. When seedlings are 2 cm to 5 cm tall, thin to a plant spacing of 5 cm to 6 cm. In places with missing seedlings, thin out strong seedlings and replant on cloudy days or in the evening on sunny days.

1.4.3 Cultivation and weeding. Carry out cultivation and weeding together with thinning to a stand. After watering or rain, cultivate promptly to keep the field soil loose and free of weeds.

1.4.4 Irrigation and drainage. Control moisture during the seedling stage, irrigate promptly during the green-up stage and after topdressing, and irrigate as appropriate before harvest. In the rainy season, clear drainage ditches and drain accumulated water from the field.

1.4.5 Topdressing. In early August, apply 20 kg of diammonium phosphate per 667 sq m by opening furrows and applying it into them.

1.4.6 Pinching and removing buds. From July to August, pinch the growing tips and remove buds promptly. For plants grown for more than 2 years, in the early stage of flower bud formation, cut off the stem tips with a sickle.

2 Main types of pests and diseases and their occurrence conditions. The main types of pests and diseases of Bupleurum and their occurrence conditions are shown in Appendix A.

3 Pest and disease control

3.1 Control principles. Implement the plant protection policy of “prevention first, integrated control”, and through measures such as selecting resistant varieties, cultivating strong seedlings, strengthening cultivation management, and scientific fertilization, comprehensively adopt agricultural control, physical control and biological control, together with scientific and rational use of chemical control, to keep pest damage within the allowable range. The pesticide safety interval shall comply with GB 4285-1989. For pesticide varieties without a stated pesticide safety interval, use shall be stopped 30 d before harvest. For pesticide mixtures, the safety interval of the active ingredient with the greatest persistence shall be followed.

3.2 Aphids

3.2.1 Physical control. Trap and kill aphids with yellow boards. In the early occurrence period of winged aphids, commercial yellow boards sold on the market may be used; or use 60 cm×40 cm rectangular cardboard or wooden boards, etc., coated with yellow paint, then coated with a layer of machine oil, and hung between rows and plants, with 30 to 40 boards hung per 667 sq m.

3.2.2 Biological control. When aphid numbers are low in the early stage, protect and utilize natural enemies such as ladybugs for natural control. In the early occurrence period of wingless aphids, spray 0.3% matrine emulsion at 800 times to 1000 times dilution, or natural pyrethrin at 2000 times dilution for control.

3.2.3 Chemical control. Spray alternately with 10% imidacloprid wettable powder at 1000 times dilution, or 3% acetamiprid emulsifiable concentrate at 1500 times dilution, or 25% pymetrozine wettable powder at 3000 times dilution, or other effective agents for control.

3.3 Red spider mites. In the early occurrence period, spray 1.8% abamectin emulsifiable concentrate at 2000 times dilution, or 0.36% matrine aqueous solution at 800 times dilution, or natural pyrethrin at 2000 times dilution, or 73% propargite emulsifiable concentrate at 1000 times dilution, or hexythiazox (5% nissorun emulsifiable concentrate) at 1500 times to 2000 times dilution for control.

3.4 Black cutworm

3.4.1 Poison bait trapping. Per 667 sq m, use 0.5 kg of 90% trichlorfon crystals, add 8 kg to 10 kg of water, and spray onto 40 kg of roasted cottonseed cake or roasted wheat bran to make poison bait. Scatter it around the seedlings in the evening to trap and kill larvae.

3.4.2 Chemical control. Use 200 g/L chlorantraniliprole suspension concentrate at 5.0 to 6.0 g per 667 sq m, sprayed during the 1st to 2nd instar stage of black cutworm, which has a good control effect on it.

3.5 Yellow swallowtail butterfly (golden swallowtail)

3.5.1 Biological control. During the peak egg-laying period or peak egg-hatching period, spray 10 billion/g live spore Bt wettable powder at 200 times dilution, or Qingchongjun (containing 10 billion/g spores) at 300 times dilution, or flufenoxuron (5% cascade) at 2500 times dilution. Spray once every 7 d, generally for 2 to 4 consecutive sprays.

3.5.2 Chemical control. Spray lambda-cyhalothrin (2.5% kung fu emulsifiable concentrate) at 4000 times dilution, or bifenthrin (10% talstar emulsifiable concentrate) at 1000 times dilution, or 50% phoxim emulsifiable concentrate at 1000 times dilution, or 90% trichlorfon crystals at 800 times dilution.

3.6 Root rot

3.6.1 Agricultural control. Select plots with deep sandy loam soil, slightly higher terrain and smooth drainage for planting to prevent water accumulation; implement rational crop rotation; fertilize rationally, apply nitrogen fertilizer appropriately, increase phosphorus and potassium fertilizers, and improve plant disease resistance; promptly pull out diseased plants and burn them.

3.6.2 Chemical control

3.6.2.1 In the early stage of disease, drench holes or irrigate roots with thiophanate-methyl (70% topsin wettable powder) at 700 times dilution, or 58% metalaxyl-mancozeb at 600 times dilution, or 3% guangkuling (hymexazol + metalaxyl) at 600 times to 800 times dilution. Irrigate once every 7 d, for 2 to 3 consecutive irrigations. For plots with a relatively high disease incidence, irrigate roots with thiophanate-methyl (70% topsin wettable powder) at 1000 times dilution along with watering, or irrigate holes with 5% lime milk, and remove diseased plants.

3.6.2.2 After pulling out diseased plants, irrigate the diseased holes with the above agents to prevent spread.

3.7 Leaf spot

3.7.1 Agricultural control. Before winter begins, thoroughly remove diseased residues from the field and burn them in a centralized manner or bury them deeply; strengthen cultivation management, cultivate and weed promptly, fertilize and irrigate rationally, and drain promptly after rain.

3.7.2 Chemical control

3.7.2.1 Before disease onset, spray Bordeaux mixture at 1:1:150.

3.7.2.2 In the early stage of disease, spray 50% carbendazim at 800 times dilution, or 65% mancozeb at 1000 times dilution, or thiophanate-methyl (70% topsin wettable powder) at 800 times to 1000 times dilution and other agents for control, spraying once every 10 d to 15 d depending on disease severity.

4 Harvesting. Harvest can be carried out after 2 full years of planting, digging from October to November when the aboveground stems and leaves begin to wither. Before digging, first cut off the aboveground stems 3 cm to 5 cm above the ground, then dig a ditch about 25 cm deep beside the bed, and then dig along the bed. For the harvested Bupleurum, remove soil, rhizome heads and stems and leaves completely, and dry in a ventilated and cool place.