How to propagate Cornus officinalis seedlings

Cornus officinalis is a famous medicinal tree species in China, its pericarp contains a variety of amino acids, trace elements and vitamins, which has the function of warming and tonifying the liver and kidney, consolidating essence and absorbing sweat. In addition, Cornus officinalis is an excellent urban and rural greening tree species with bright yellow flowers in early spring, green leaves in summer, red fruit in autumn and vigorous branches in winter.

Cornus officinalis is a small deciduous tree with a height of 3 meters to 5 meters, flowering from late February to early April, flowering first and then leaves, fruit maturing from September to October, generally red at maturity, and a few varieties are bluish white. Cornus officinalis grows best in deep, fertile, loose and organic matter-rich sandy loam with pH between 5.0 and 6.5. Cornus officinalis is more shady but likes sufficient light, so it can be planted on shady and semi-shady slopes, and sunny slopes can be planted at high elevations.

Seed reproduction

The excellent seed-collecting mother trees with strong growth and no diseases and insect pests were selected and began to be collected around September when the seeds were fully mature. The fruits with large color and full grains were selected from the collected fruits and dried for 3 to 4 days. After they were softened, the flesh was peeled off and dried.

The seeds of Cornus officinalis have the characteristics of deep dormancy, hard kernels, containing a transparent mucus resin, impervious to water and air, affecting seed germination. If directly sown, seedlings will not emerge until the second year or even the third year. Therefore, seed germination must be carried out before sowing. The treatment methods include chemical treatment method, stratification sprouting method, human feces and urine heap method, nursery surface burning method and so on.

The sandy loam soil with flat topography, fertile soil and good drainage is selected as the nursery land, which is ploughed deeply with sufficient bottom fertilizer in winter, and the base fertilizer is better with stable fertilizer and plant ash. Make a bed after shallow ploughing and raking before raising seedlings in spring. Soil disinfection should be carried out in the nursery land where mole cricket, grub and other underground pests are easy to occur.

Sowing is divided into autumn sowing and spring sowing, and spring sowing is mostly used in production. Spring sowing is usually carried out after soil thawing from February to March, while autumn sowing is usually carried out before soil freezing from September to November. Using strip sowing method, row spacing 20 cm to 30 cm, ditch depth 4 cm to 5 cm, watering and sowing in the ditch, covering soil 2 cm to 3 cm, covered with wet grass.

The seedlings can emerge about 25 days after sowing, and when the seedlings are unearthed up to 70%, the covered grass on the seedbed should be removed 2 to 3 times. During the period of seedling growth, loosen the soil and weed in time, control diseases and insect pests. Seedlings with a height of more than 10 cm can be fixed between seedlings and fertilized appropriately when 20 cm. After the seedlings enter the fast-growing period in July, it is necessary to strengthen fertilizer and water management. In September, in order to accelerate its Lignification, we should stop applying nitrogen fertilizer and increase the application of phosphorus and potassium fertilizer. When the seedlings are as high as 60 cm to 100 cm, they can come out of the nursery.

Vegetative reproduction

The seedlings of Cornus officinalis can only blossom and bear fruit after 6 years of afforestation, while the good characters of the mother plant can be maintained by using vegetative propagation seedlings, which can blossom and bear fruit in 4 years. The common vegetative propagation methods are cutting, grafting and striping.

Cutting propagation is generally selected from April to May. On the excellent type of mother tree, the 2012 branches with strong growth and no diseases and insect pests are selected and cut into cuttings 15 cm to 20 cm long. The upper incision is cut into a flat cut, and the lower incision is cut into an oblique notch. About 4 leaves are retained on the cuttings, and the rest of the leaves and petioles are all cut off. Use humus and fine sand in equal proportion to make a cutter, trench according to 20 cm row spacing on the cutter, cut 8 cm to 10 cm plant spacing in the ditch, and cover the soil at the same time. Pour water once after insertion and cover the agricultural film. Remove the agricultural film in mid-June and put it in a shade with a transmittance of 10%. It will take about 90 to 100 days to take root and survive.

Grafting propagation of Cornus officinalis is generally carried out by seedling grafting, and other species of the same family, such as smooth bark tree, lampstand tree, Sizhao flower, etc., can be used as rootstocks. For the seedlings used as rootstocks, it is best to grow in 2012 and the stem is 0.6 cm to 1 cm. Select an excellent type of middle-aged mother tree that is strong and disease-free, collect fully developed annual branches in the middle and upper part of the crown, cut them into 10 cm to 15 cm long, and seal the upper and lower incisions of the scion with paraffin wax. After sealing the wax, store the scion in a low temperature place for grafting. The suitable grafting period is from April to September.

Striping propagation every autumn in October, select the excellent type of mother tree with strong growth and about 10 years old, bend the sprouting branches around the rhizosphere or the branches close to the ground to the ground, and carve them to the xylem where they are ready to take root. Then it is buried in a 15cm hole, compacted with soil, the branches exposed above are fixed on the wooden stake, and the management is strengthened, and the new roots are cut and planted with the mother plant.