Detailed Explanation of Key Points for Pollution-Free Cultivation Techniques of Salvia miltiorrhiza

1. Scope

This standard applies to pollution-free open-field production of Salvia miltiorrhiza in Hebei Province. This standard specifies the environmental technical conditions of the production area for pollution-free Salvia miltiorrhiza with a yield of 4500 kg to 5200 kg per hm2, the principles and requirements for fertilizer use, production management and a series of other measures.

2. Pollution-free production management measures

Salvia miltiorrhiza is mainly propagated by root division. Varieties propagated by root division for many years are prone to degeneration, so after several years of root division propagation, seed propagation is needed to facilitate variety purification and rejuvenation. Propagation by rhizome buds (which can set seed in the same year) and cuttings can also be used.

2.1 Propagation

2.1.1 Root division propagation

When harvesting Salvia miltiorrhiza each autumn, select thick, red, non-rotting, well-developed annual root strips with a diameter of 0.7 cm to 1 cm and no pests or diseases as seed roots, and store them in wet sand until planting the following year. Alternatively, select robust, pest- and disease-free plants and leave them in place without digging them up as seed plants, then dig and plant them as needed the following year. Root division propagation is harvested in the autumn of the same year or the spring of the following year.

2.1.2 Seed propagation

Sow around April 20. For the sowing site, choose a plot with relatively high terrain and loose soil. Deeply plow before sowing, apply 2500 kg of decomposed organic fertilizer per 667 m2 as base fertilizer, break up the soil finely and rake it level, make beds 1.2 m wide, level the bed surface, open furrows on the bed surface at a row spacing of 33 cm and a depth of 1 cm, mix the seeds with fine sand, sow them evenly into the furrows, and cover with fine soil just until the seeds are no longer visible. The seeding rate is about 0.5 kg to 1 kg per mu. After the seedlings emerge, thin and fix the seedlings in combination with intertillage and weeding. When the seedlings have 2 to 3 true leaves, apply the first topdressing, applying 1500 kg of decomposed human and livestock manure water per 667 m2. In late July, apply the second topdressing, with 15 kg of urea plus 10 kg of diammonium phosphate per 667 m2. Water during drought and drain promptly after rain. In addition, except for seed-production fields, flower bolts should be cut off promptly. Seed propagation can be transplanted in the same year, or the roots can be used as seed roots for root division propagation the following year.

2.2 Planting techniques for root division propagation

2.2.1 Site selection

Choose a plot where the previous crop was a grass-family crop, the soil is relatively fertile, the soil layer is deep, the terrain is relatively high, and drainage is good. Sandy loam is better.

2.2.2 Land preparation

Plow the plot to a depth of more than 20 cm, rake it fine and level it, make beds 1.2 m wide, and open drainage ditches around them.

2.2.3 Fertilization

Base fertilizer is mainly high-quality organic fertilizer, commonly used chemical fertilizers, compound fertilizers, etc. Under medium fertility conditions, in combination with land preparation, apply 2000 kg of high-quality organic fertilizer, 5 kg of nitrogen fertilizer (N) (equivalent to 10.9 kg of urea), 6 kg of phosphate fertilizer (equivalent to 50 kg of superphosphate), and 4 kg of potassium fertilizer (k2o) (equivalent to 8 kg of potassium sulfate) per 667 m2. 2.2.4 Planting Plant at the appropriate time in late March. On the well-prepared and finely raked beds, open furrows or holes at a row spacing of 20 cm, plant spacing of 25 cm, and depth of 5 cm to 7 cm. Cut the seed roots into small sections of 5 cm to 7 cm and plant them in their original orientation; they must not be inverted. Place one section per hole, cover and press flat. Each hm2 requires 1200 kg to 1500 kg of seed roots, and about 6000 plants are retained per 667 m2.

2.2.5 Intertillage and weeding

Generally carried out 3 times. The first time is when the seedlings are about 10 cm tall, and subsequent times depend on weed growth. Intertillage should be shallow hoeing.

2.2.6 Topdressing

After planting Salvia miltiorrhiza, when sufficient base fertilizer has been applied, generally topdress once, and in special cases twice. In late June, during the vigorous growth period of the plants, apply 20 kg of urea per 667 m2. In mid-to-late July, spray the leaves with 50 kg of 0.1% potassium dihydrogen phosphate or 2% superphosphate extract.

2.2.7 Drainage and irrigation

Salvia miltiorrhiza dislikes waterlogging. After rain, ditches should be cleared promptly to remove standing water in the field and prevent waterlogging, which can cause root rot. May to July is the vigorous growth period of Salvia miltiorrhiza, when water demand is relatively high. If drought occurs, water promptly.

2.2.8 Bud removal

Except for seed-production fields, remove buds in stages and batches after early to mid-July. It is better to do this early than late, so that nutrients are concentrated in root growth. When picking, be careful not to damage the stems and leaves.

3. Pest and disease control

3.1 Root rot

3.1.1 Agricultural control

3.1.1.1 Reasonable crop rotation can inhibit the accumulation of soil fungi.

3.1.1.2 Use disease-free planting material.

3.1.1.3 Fertilize reasonably, apply sufficient base fertilizer, apply more organic fertilizer, increase phosphorus and potassium fertilizer, topdress promptly, cultivate strong seedlings, and adopt health-promoting cultivation.

3.1.2 Chemical control

3.1.2.1 Soak seed roots before planting: dip the roots in 800-fold liquid of 50% carbendazim or 70% thiophanate-methyl for 10 min, then plant after drying.

3.1.2.2 Chemical control: during the disease period, drench the roots with 800-fold liquid of 50% carbendazim or 1000-fold liquid of 70% thiophanate-methyl, applying about 250 ml of medicinal liquid per diseased plant, then drench again after 7 d to 10 d, for 2 to 3 consecutive times. The following agents can also be sprayed: 1000-fold liquid of 70% thiophanate-methyl or 1000-fold liquid of 75% chlorothalonil, using 50 kg of medicinal liquid per 667 m2 each time, spraying once every 10 d, for 2 to 3 consecutive sprays. Be sure to spray the base of the stems.

3.2 Root-knot nematode

3.2.1 Agricultural control

3.2.1.1 Implement crop rotation, preferably with grass-family crops.

3.2.1.2 Use disease-free planting material.

3.2.1.3 Cultivate strong seedlings, improve the stress resistance of the plants themselves, and adopt health-promoting cultivation.

3.2.2 Chemical control In combination with land preparation, apply 45 kg of 3% phoxim granules per hm2, scatter them on the ground, and turn them into the soil for soil disinfection; or use 3 kg to 3.75 kg of 50% phoxim emulsifiable concentrate diluted with 10 times water into 30 kg to 37.5 kg of medicinal liquid, spray it onto 375 kg to 450 kg of fine soil and mix well to make “toxic soil”, scatter it evenly on the ground in combination with land preparation, and turn it into the soil; or scatter this “toxic soil” along the ridges near Salvia miltiorrhiza. If it can be applied before rain, the effect is even better.

3.3 Leaf spot

3.3.1 Agricultural control

3.3.1.1 Rotate crops; do not plant Salvia miltiorrhiza in the same plot for more than two cycles.

3.3.1.2 After harvest, promptly clear dead branches and fallen leaves from the field and burn them in a centralized manner.

3.3.1.3 Increase phosphorus and potassium fertilizer or spray 0.3% potassium dihydrogen phosphate on the leaves, 50 kg per 667 m2, to improve the disease resistance of Salvia miltiorrhiza.

3.3.2 Chemical control

In the early stage of the disease, use 50% wettable carbendazim powder made into 800-fold to 1000-fold 50 kg medicinal liquid per 667 m2 each time and spray the leaf surface, once every 7 d to 10 d, for 2 to 3 consecutive sprays.

3.4 Underground pests (white grubs, wireworms)

3.4.1 Agricultural control

3.4.1.1 Intensive and meticulous farming, deep plowing and repeated harrowing, reasonable crop rotation, and reasonable fertilization and irrigation can all reduce pest population density and lessen damage.

3.4.1.2 Apply fully decomposed organic fertilizer.

3.4.1.3 Carry out manual capture in combination with land preparation and deep plowing

3.4.2 Physical control

Use black light traps at night to kill adult insects.

3.4.3 Chemical control

3.4.3.1 In combination with land preparation, use 15 kg to 22.5 kg of 5% phoxim granules per hm2, mix evenly with 225 kg to 450 kg of fine soil, and scatter.

3.4.3.2 When a large number occurs, use 50% phoxim emulsion diluted to 1000-fold to 1500-fold liquid or 1000-fold liquid of 90% trichlorfon, 100 kg, remove the sprayer nozzle, and pour along the ridges at the roots.

4. Harvesting

4.1 Seed harvesting

In early to mid-October, when two-thirds of the fruit shells of the Salvia miltiorrhiza seed spikes turn withered yellow, cut off the seed spikes with scissors, remove the immature part at the top of the seed spikes, tie them into bundles, place them in a ventilated place to dry for 2 d to 3 d, and thresh promptly. Then clean and select to remove shriveled grains and impurities, and store for future use.

4.2 Harvesting of the medicinal (root) part

When Salvia miltiorrhiza has grown in the field for one year (autumn of the same year) or more than one year (spring of the following year), and the chemical components of the root (the root is used as medicine) meet the quality standard (tanshinone content not less than 0.3%, salvianic acid A content not less than 1.2%), dig in early November, when the aboveground part begins to wither and the soil moisture is suitable, choosing a sunny day. Leave the dug Salvia miltiorrhiza in place to sun-dry until the soil on the roots is slightly dry, cut off the aboveground parts such as stems and rhizome heads, remove soil, load into baskets and transport to the drying yard for air-drying, or use a dryer for drying. When digging, dig as deeply as possible; do not pull by hand. During loading and transport, do not squeeze, do not tread on it, and do not let it contact water or be exposed to rain.