What are the key points for sowing and raising seedlings of Atractylodes macrocephala?
1. Seed treatment: Carefully remove all debris from the seeds, then use a 1000-fold solution each of thiophanate-methyl + carbendazim + abamectin (that is, 100 jin of water plus 1 liang of the pesticide), mix the above three pesticides into an aqueous solution, soak the Atractylodes macrocephala seeds in the solution for 36 hours, then scoop them out and dry them in the shade (until the outer skin is dry) before sowing.
2. Land selection and preparation: For flat land, choose virgin wasteland or sandy loam soil where crops have not been planted for more than 3 years; for mountain land, choose sandy soil with deep soil layers and no or few root weeds, and the slope of the land should not be too steep; clay land or heavily alkaline land must not be planted. Apply 3000 kg of farmyard manure or soil-mixed manure per mu as base fertilizer. If there is no or little farmyard manure, you can apply 80 kg of potassium sulfate-type compound fertilizer (chlorine-containing types must not be used) + 50 kg of superphosphate. If there are underground pests in the soil, pesticide for killing insects must also be applied before plowing; after fertilizing, plow the soil 20 cm deep, rake it fine and level, and make beds 1-1.2 m wide.
3. Sowing time: Depending on the region, generally during the period from Qingming to Guyu, from late March to early May, when the ground temperature at 5 cm stabilizes above 12 degrees, this is the best sowing time.
4. Sowing method: Generally drill sowing is used, with row spacing of 15 cm, opening furrows on the bed surface, furrow depth 3 cm, furrow width 5 cm, and the furrow bottom should be flat. Evenly scatter the treated Atractylodes macrocephala seeds by hand in the furrows, striving to keep the seed spacing at about 1 cm, and cover with soil just enough to cover the seeds (1-2 cm); according to soil moisture conditions, if the soil moisture is high, press down lightly, and if the soil moisture is low, press down more firmly. For large areas, a drill seeder or mechanized sowing can also be used (which can increase sowing speed 10 times). After sowing, cover with rice straw or leaves to keep the soil moist. When the temperature reaches about 20 degrees, seedlings can emerge 7-10 days after sowing. The seeding rate per mu is 5-8 kg.
5. Field management: When about 80% of seedlings have emerged, remove the covering grass. When the seedlings are 10-15 cm tall, shallowly loosen the soil once together with weeding, and at the same time thin the seedlings to a plant spacing of 3-4 cm (this should not be done after rain or when dew has not dried). In dry weather, water frequently with a small amount of water. After thinning, apply 25 kg of urea per mu; in the mid-growth period from June to July, apply 20 kg of urea + 20 kg of potassium sulfate compound fertilizer per mu; in August to September, apply another 30 kg of potassium sulfate compound fertilizer. Water immediately after each fertilization.
6. Pest and disease control:
(1) Damping-off: Drain promptly and prevent soil crusting. Spread 5 kg of gypsum powder per mu to improve soil permeability. In the early stage of the disease, water the plants with 5% lime water, once every 7 days, for 2-3 consecutive times.
(2) Iron leaf disease: It is most severe from mid-June to early July. When diseased leaves are found, remove them promptly and burn them. Or use 1:1:100 Bordeaux mixture for spray control, once every half month, spraying 3 times consecutively. If it rains after spraying, spray once again.
(3) Rust disease: Apply more phosphorus and potassium fertilizer to improve disease resistance, or in the early stage of the disease spray with a 400-fold solution of triadimefon or fenaminosulf.
(4) Southern blight: This is one of the main diseases of Atractylodes macrocephala. A 1000-fold solution of 50% carbendazim can be used to irrigate the affected area.
(5) Root rot: In the early stage of the disease, use a 1000-fold solution of 50% thiophanate-methyl and a 1000-fold solution of 50% captan for spray control.
(6) Insect pests of Atractylodes macrocephala: They can be controlled with malathion emulsifiable concentrate, dimethoate and pyrethroid pesticides. Before the adults lay eggs, spray a 300-fold solution of 50% dichlorvos, once every 7-10 days, spraying 2-3 times consecutively.
7. Harvesting and seed reservation:
In the same year, from Frost's Descent to the Beginning of Winter, when the leaves of Atractylodes macrocephala seedlings turn yellow and withered, choose a sunny day, dig up the rhizomes (that is, the planting stock), cut off the stems (leaving 1 cm) and the fine roots at the tail, remove diseased and damaged plants, spread them in a cool and ventilated place for 1-2 days, and store them after the surface of the planting stock turns white.
For storage of the planting stock, choose an indoor mud floor that is cool, dry and protected from sunlight, spread fine sand with 20% moisture content 5 cm thick, place the planting stock 8-12 cm on top, then add another layer of fine sand, pile in this way to a height of 30-40 cm, then cover with 4 cm of sand or fine soil. Insert a bundle of straw every 50 cm in the center of the pile to release moisture and heat. In severe winter, cover with rice straw to prevent freezing. During storage, check once every 20 days, turn the stock over from top to bottom, and promptly remove diseased stock when found. Do not light a fire indoors, and do not sprinkle water on the pile of planting stock.
In warmer regions, they may not be dug up, and before sprouting in February of the following year, plant them while digging.