The Seedling technique of Oil Purple spot Tree Peony covered with Sand in High bed

Seedling raising technique of oil purple-spotted peony on high bed covered with sand

Paeonia suffruticosa Andr. var. Papaveracea), also known as Gansu peony, northwest peony, belongs to the genus Paeonia of Ranunculaceae, deciduous shrub. Peony is named for its obvious color spot at the base of petals, which has high ornamental value. Although wild species are distributed in Gansu, Shaanxi, Henan and Hubei, cultivated varieties are mainly distributed in Sichuan, Gansu, Qinghai, Shaanxi and Ningxia provinces (autonomous regions). The branches of the purple peony are short and thick. Leaves are usually bi-tertiary compound leaves, surface green, glabrous, back light green, sometimes with white powder, flowers solitary branch top, petals 5 or double, rose, reddish purple, pink to white, flowering May, fruit 8 to September mature.

Peony bolleana is an excellent variety in Chinese peony variety group. It has drought resistance, cold resistance, saline-alkali resistance and slow aging. It originates from the damaged forest in Gansu alpine area and grows normally on the mountain with an altitude of 1100~3200m. The lowest temperature in winter in this area generally reaches minus 30℃, and in some areas it can reach minus 38℃, so this variety is naturally cold resistant. In Gansu Zhongchuan annual rainfall only 280mm can grow, adapt to the soil range is large, from slightly acidic to slightly alkaline (pH 6.5~8.2) sand to clay can grow well. Hillside, ditch bottom, terrace, sandy land can be planted.

1. Selection of seedling sites

Choose a sandy loam with flat terrain, easy irrigation, good drainage, loose soil and fertile soil.

2. Make a bed

After selecting the seedling site, apply decomposed organic fertilizer 37500kg/hm2, compound fertilizer 600kg/hm2, and apply soil insecticides and fungicides before sowing. After fine harrowing in sunny days, leveling, irrigating sole water, making seedbed with length of 5~ 10m, width of 1.2m, height of 0.15m and footpath of 0.3m when the ground surface is slightly dry and the soil is loose. The seedbed is required to be level without ponding and fine soil particles.

3 Seed treatment

3.1 seed picking

To cultivate high-quality and high-yield seedlings of peony, we must select new seeds with full seeds and no diseases and insect pests, and absolutely not use old seeds. There is epicotyl dormancy in M. aurea. Therefore, seed should be harvested from early August to September after the pericarp turns brown.

3.2 disinfection soak

Soak seeds with 0.5% potassium permanganate solution for 0.5h, remove them, wash them with clean water, select seeds with clean water, store them in wet sand for about 7 days, sow them, germinate at low temperature in winter.

4 sowing

4.1 seeding rate

The sowing rate of peony is determined according to the soil fertility and seed weight of seedling land, generally 750 kg/hm2.

4.2 sowing time

The epicotyl dormancy of seed of M. aurea L. is observed. The seed should be sown immediately after maturity. The sowing time of oil peony is generally from late August to early and middle September, and the most suitable sowing time is late August in Liupan Mountain area of Ningxia. Sowing late or in the spring of the following year often delays germination by a year.

4.3 sowing method

Sowing adopts horizontal wide drilling, sowing width is 10 cm, sowing depth is about 3 cm, row spacing is 10 cm, and three people are in a group when sowing, that is, one person furrows, one person sows seeds and one person covers sand. The specific operation is that the trencher uses a special wooden rake (rake head length: 1m, rake tooth width: 10 cm, tooth spacing: 10 cm) to horizontally open a sowing ditch with a depth of about 3 cm on the seedbed; the seed sower will evenly spread the seeds in the ditch; the sand covered person will then spread sand cover, covering the thickness of about 3 cm. After a plot is sown, it is necessary to divert water for flood irrigation. The speed of flood irrigation is not to wash away sand and seeds. The amount of irrigation is to submerge the bed surface, but it is not allowed to accumulate water. Seeds germinate about 1 month after they are laid on the ground, and radicles grow. The seedlings were unearthed from late March to early April of the following year.

5 Post-sowing management

The seeds germinated and took root 20~30 days after sowing. If the weather is dry in winter, cover the garden with straw 2 cm thick to protect it from overwintering. At the end of March and the beginning of April of the next year, after the seeds were released from epicotyl dormancy by winter low temperature, the buds sprouted one after another. Give seedlings moderate shade depending on weather conditions.

5.1 intertillage weeding

To do there is grass that hoe, avoid weeds after weeding. In rainy seasons in spring and summer, weed should be weeded every time the ground dries after rain. The newly unearthed sprouts are fragile and easy to break. Be careful not to bruise the sprouts when weeding.

5.2 fertilization and watering

In spring, according to the moisture content, timely irrigate three times or so, and combine irrigation topdressing urea 75~150/hm2, weeding when the soil is white and slightly dry after each irrigation.

5.3 flood prevention and drainage

Rainy weather should be timely clear ditch drainage, prevent nursery water, so as not to cause seedlings flooded root rot.

5.4 thinning

In order to cultivate strong seedlings, seedlings should be thinned in time. 750 000 plants/hm2 was suitable for seedling production.

5.5 antifreeze

After winter, straw should be covered in time to prevent frostbite of seedlings.

6 Pest control

When the temperature rises to 18~25℃ in spring, it is the rapid growth period of seedlings. At this time, attention should be paid to the occurrence and harm of fungal diseases. Bactericide, foliar fertilizer 0.3% potassium dihydrogen phosphate and growth promoter can be used together or separately, and they can be used continuously for three times between March and April, with good results.

7 out of nursery transplanting

The seedlings of oil peony can be planted in late August to early September in Liupan Mountain area of Ningxia. Transplanting too early, because the temperature is high, the survival rate of transplanted seedlings is low; transplanting too late, it is difficult to form new roots in the year, and the growth is weak in the coming year. Seedlings should be transplanted in moderate soil moisture, preferably in windless weather. Do not touch the sprouts and damage the roots when seedling. Peony is a fleshy root, easy to break, should be graded seedlings placed in the shade for 1~2 days, until the fleshy root slightly soft can be planted. Before planting, roots of seedlings were treated with 1‰ potassium permanganate and 0.1% APT rooting powder solution, which could reduce the occurrence of diseases and insect pests, promote the healing of roots and improve the survival rate.