Lamination of asexual reproduction of Cornus officinalis

Dogwood, also known as jujube bark, jujube medicine, jujube, to the core of the pericarp called dogwood pulp, dogwood pulp, it is China's unique woody Chinese herbal medicine, widely used, medicinal value, economic value and ornamental value are very high, has always been a hot medicine in the domestic and foreign pharmaceutical market, in recent years due to the increase in export volume, the price per kilogram rose to 140- 180 yuan. For many years, dogwood has been using seed seedling propagation, from sowing to fruit, often takes 8-10 years, even if the management is fine, strong growth of plants, it takes about 7 years to bear fruit. Foping County of Shaanxi Province is one of the three major cultivation bases of Cornus officinalis in China. After more than 10 years of exploration, the author and scientific and technological workers have adopted the asexual propagation method-layering, which not only keeps the excellent characters and characteristics of the selected mother plants, but also makes Cornus officinalis bear fruit earlier, grow fast and produce high yield. Self-rooted seedlings cultured by layering on 10- 15-year-old mother plants can blossom and bear fruit after two years, 6- 8 years earlier than seed-bred seedlings, and the fruits are large, thick and of good quality. Cornel layering is characterized by water and nutrients needed before layering takes root, which can be supplied by mother plant, reliable rooting, simple method and high survival rate. The layering time can be carried out after fruit picking in autumn or after soil freezing in spring and before bud germination.

I. Layering method

1. Ground layering. Select 10-15 years old, healthy, no diseases and insect pests, early fruit, high yield, good quality trees as mother plants. Twist and bend the branches close to the ground, 2-3 years old, about 1 cm in diameter and 100- 150 cm high to the ground, or parallel to the ground, cut the shady surface of the branches (i.e. the parts close to the ground) to the depth of 1/3 of the xylem (do not cross the center to prevent the branches from breaking), bury the branches in the soil plowed in advance and applied with organic fertilizer, or after circular peeling, fix the buried parts, compact the upper parts with soil, and expose the top of the branches to the ground. This treatment can promote the pressed parts to take root. Fibrous roots can be formed after half a year.

2. Air layering. This method is suitable for dogwood trees with tall tree bodies and difficult sprouting branches at the lower end. its method is: choose 2-3 year old branch, cut or peel that base of the pressed branch in a circular way, peel the width of 2-3 cm, then fill wet soil in the opened bamboo tube or earthen jar, bury the layering in the middle, and keep the soil in the bamboo tube or earthen jar wet constantly. After rooting, cut off from the lower end of the root for planting.

II. Management after layering

After layering, the moisture content of soil should be maintained to 60%-80% of the maximum water holding capacity. In addition, the soil permeability near the layering position is also very important. If it is clay or sandy loam with poor structure, it should be improved. In addition to applying sufficient base fertilizer during layering, a small amount of decomposed organic fertilizer should be applied in the spring of the following year, which can promote the healthy growth of layering seedlings.

III. Planting

In the late autumn of the second year of layering (before the leaves fall, the leaves are used for photosynthesis to produce and transport nutrients for the roots) or in the third spring, the part connected with the mother plant can be cut, and the separated self-rooted seedlings can be taken out with soil. In the selected plot, the pit is planted according to the specified method.