High-yielding cultivation techniques of Platycodon grandiflorum

Platycodon grandiflorum is the dry root of Platycodon grandiflorum of Platycodon grandiflorum family, wild or cultivated, and is produced in most areas of our country.

Platycodon grandiflorum is not strict on the climate environment, but it is suitable for mild and humid, sunny and rainfall-rich environment, and can withstand cold. The best soil is sandy loam which is deep, fertile, well drained and rich in humus.

Before sowing, the seeds are soaked in warm water for 24 hours or 0.3% potassium permanganate for 12 hours, which can also be treated with ultrasonic wave, which can significantly improve the seed germination rate.

Cultivation techniques

1 selection and preparation of land

Platycodon grandiflorum is a deep-rooted perennial crop, like sunny, cool and humid environment, cold resistance, avoid stagnant water. Choose the hills of Pingchuan with an altitude of 450m and 1500m, and choose mountains to avoid the wind and the sun, loose and fertile sandy soil or sandy soil with high humus content. The soil that is too loose, dry or yellow mud is not easy to grow, and the roots are bifurcated. In the selected plot, deep ploughing about 35cm, combined with the application of bottom fertilizer, can apply farm manure of 60000-75000 kg/ ha, break the soil block, and form a flat border with a width of 1.3m and 1.7m. The areas with more Rain Water and convenient irrigation can also make high borders, with a width of 1.5m, a high 15--20cm and a ditch of 15mur20m.

2 sowing

Platycodon grandiflorum can be sowed in spring, summer and autumn, and the autumn sowing is the best from late October to early November. The seedlings emerge in the same year after sowing, the growth period is long, and the fruiting rate and root diameter are significantly higher than those of spring sowing. In the northern region, wheat stubble can be sown in summer, the land utilization rate is high, and the seeds are easy to germinate, so it is worth advocating. Direct seeding is generally used, but seedling transplanting is not recommended, because the yield of direct seeding is higher than that of transplanting, and the root quality is obviously better than transplanting. During strip sowing, horizontal trenches were opened on the border according to row spacing 15--20cm, deep 5--7cm, sowing width 10cm or so; when burrow sowing, one hole was dug every other 8--10cm, and the seeds were scattered. Cover with fire ash or fine soil after sowing.

(3) fixing and replenishing seedlings

The seedlings are fixed when the seedlings are high and 2cm. During strip sowing, one strong seedling was kept at the distance between seedlings (8--10cm), and two seedlings were kept at each hole interval (6cm). Seedling replenishment and seedling fixing are carried out at the same time, and planting with soil is easy to survive for ridges or holes lacking seedlings.

4 topdressing and weeding

The first weeding was carried out at inter-seedling stage, first inter-seedling, then weeding, then applying calcium superphosphate 150.0kg/ ha, and then applying light human feces and urine water 12000 kg/ ha in the ditch or hole, and avoiding seedling cover fine soil. The second fertilization was carried out 60 days after the first topdressing. 25000 kg/ ha of farm manure and 18000 kg/ ha of human and animal feces and urine were applied to the cave and weeded to cultivate the soil. In the third topdressing, about 23000 kg/ ha of human feces and urine and 75.0--105.0kg/ ha of urea were applied at the height of seedlings in the second spring and before flowering, and weeding was carried out.

(5) sprouting and bolting

The flowering period of Platycodon grandiflorum is longer, and the growth and development of flowers and fruits consume a lot of nutrients. Sprouting and bolting is a measure to increase production. Except for the selected seed plants, the spraying concentration of 0.1% ethephon at full flowering stage and bolting stage can basically achieve the purpose of flower removal. In order to promote the growth of the main root, the branch buds must be knocked off, only two main buds are left in each plant, and the rest are removed and eaten.

(6) Disease and pest control

6.1 when the root nematode disease is damaged, there are diseased protuberances in the root, and the aboveground stems and leaves wither early. Control method: applying 1500kg/ hectare tea seed cake fertilizer as base fertilizer can reduce the harm and disinfect the soil with lime nitrogen or dibromochloropropane before sowing.

6.2 purple stripe feather disease

The damage was serious in the middle of September and the root rotted in October. The damaged roots turned red at the initial stage and were covered with reticulated reddish-brown hyphae. In the later stage, the purple sclerotia of mung bean was formed, and the stems and leaves withered and died. Prevention and control methods: avoid continuous cropping, implement crop rotation, remove diseased plants and burn them, and disinfect the diseased points with 5% lime water.

6.3 anthracnose

7Mel-August, when the temperature and humidity were high, it was easy to occur and spread rapidly, and the plants lodged and died, which mainly harmed the base of the stem. At the initial stage, brown spots appeared at the base of the stem, and gradually expanded around the stem. In the later stage, the disease contracted and the plant lodged. Prevention and cure method: spray with 500 times solution of 20% bacillus special wettable powder before the seedling is unearthed, spray 1% 100 Bordeaux solution or 50% methyl thiophanate wettable powder 800 times liquid at the initial stage of the disease, once every 10 days, spray 3 Mel 4 times in a row.

6.4 Ring streak and spot blight

Damage to the leaves, spray 1vl 100 Bordeaux liquid or 50% carbendazim wettable powder 1000 times at the initial stage of the disease, spray 2 Mel 3 times in a row.

6.5 paraphernalia

To harm the roots of Platycodon grandiflorum, it can be sprayed with 1000 times of 90% trichlorfon or 50% phoxim EC during 3-April adult mating period and 5-month larval stage.