Propagation methods of planting jujube seedlings

Jujube tree is an important fruit tree in China. Its root system is developed. Some roots close to the ground can grow vigorous tiller seedlings. It is an important method to develop jujube tree by using tiller seedlings. The ramet propagation of jujube root tillering seedlings is divided into the following two steps.

I. Root cutting and seedling promotion

Although jujube can self-produce tiller seedlings, but the number is small, in order to stimulate the formation of tiller seedlings can be used to cut roots. The specific method is as follows: when the ground temperature rises in spring and the root system begins to move, dig a ditch on one side of the crown projection area of the superior jujube tree. The ditch depth is 50 cm and the width is 30 cm. The ditch direction is parallel to the row direction of the jujube tree, and cut off the jujube root with a diameter less than 1.5 cm (the big root does not move, so as not to affect the tree vigor of the mother tree).

After tree root is cut off, bud of concealed on small root germinates quickly, extend ground upward, develop into seedling. When the seedlings are about 30 cm high, thin them out and leave strong ones. Then cultivate the soil, the depth to reach 1/4 of the seedlings is appropriate, in order to promote the emergence of new roots at the base of the new shoots, combined with soil cultivation, fertilization and irrigation, to accelerate the growth of seedlings, generally the seedlings can grow to 60-100 cm high. The size of tillers was related to the thickness of roots.

II. Returning to nursery for seedling raising

Tillering seedlings are generally irregular in size, sometimes less fibrous roots, low survival rate of direct planting, irregular growth, difficult to manage. Nursery nursery nursery is the root tiller seedlings will be concentrated in the nursery, according to the size of separate, and then re-cultivate seedlings of a method. Jujube seedlings grow for another year in nursery, seedlings grow strong, root system is good, quality is high, seedling size is uniform, planting survival rate is high.

1. Nursery selection and soil preparation. Nursery should choose flat terrain, irrigation and drainage facilities, fertile sandy soil plots, nursery land can not be continuous cropping. Deep ploughing shall be carried out after applying sufficient base fertilizer, and irrigation and drainage channels shall be repaired according to the direction of water source. Dry areas should be cultivated in low beds, and places with much rain should be cultivated in high beds.

2. Selecting seedlings. Tillering seedlings should be strictly selected without leprosy, scale insects and other diseases and insect pests of seedlings to nursery. It is best to root and shoot seedlings with stem diameter of 0.4-0.6 cm (too thin or too thick seedlings have low emergence rate and poor growth after returning to nursery). After strict selection, the seedlings are pruned, and branches, branches or too long roots are cut off. Each plant retains a new shoot about 35 cm long, and the rest are cut off. Then according to the seedling size classification, first carry on false planting.

3. Plant seedlings. After finishing the land, dig a long longitudinal ditch, the ditch length can be determined according to the nursery land, the ditch width is 30 cm, the ditch depth is 20 cm, and the distance between the ditch and the ditch is 60-70 cm. Take out the seedlings and plant them in the ditch. The plant spacing is about 30 cm. Plant 3000-4000 plants per mu. Because jujube has secondary branches, branch angle is large, plus root tiller seedling growth is fast, so density should not be too large, more than 4000 plants, poor growth, branches and leaves closed, easy to suffer from jujube rust and other diseases. After planting seedlings, soil sealing, solidity and irrigation are carried out.

4. Seedling management. After seedling planting, the stubble is flattened, the aboveground part is cut off at 2-3 cm away from the ground, one bud with strong growth is selected after the basal bud germinates, other buds are wiped off, and then intertillage weeding, topdressing, pest control and the like are carried out according to the conventional method of seedling cultivation. Generally, after one year, the seedlings are about 1 meter high and many new roots are grown, they can be planted out of the nursery.