How to propagate jujube trees? Introduction to common propagation methods

The jujube tree is an important economic tree species in our country. The tree can be used for landscaping, and the fruit it bears can be made into various candied fruits or preserved fruits. Currently, it is being planted in many regions, so how do you propagate jujube trees?

1. Grafting

The main grafting methods include wood bud grafting and scion grafting (scion grafting mostly uses bark grafting). The key technical points of grafting can be summarized in six characters: “fresh” - the scion should remain fresh without water loss. “flat” - the cut surface of the scion should be flat. “accurate” - the cambium layers of the scion and rootstock should be aligned. “tight” - after grafting, it should be wrapped tightly and securely. “fast” - the operation speed should be fast. “moist” - after grafting, soil should be mounded or plastic bags should be used to maintain humidity. At the same time, 5-7 days before grafting, irrigate the rootstock nursery to make the bark easier to separate.

2. Root cutting

Select own-rooted plants of excellent varieties. Before sprouting, dig a trench around the outer edge of the tree canopy that is 30-40 cm wide and about 50 cm deep, cut off roots with a diameter of 2 cm or less, apply organic fertilizer in the root-cutting trench, and then backfill immediately. During the growing season, root suckers can emerge. In the spring of the following year, dig out the root suckers, treat them with ABT rooting powder or other hormones, plant them back in the nursery, and cultivate strong seedlings.

3. Root cuttings

In late autumn, in combination with autumn plowing, collect roots from robust jujube trees, cut them into root segments 20-30 cm long and 1-4 cm in diameter, and store them in sand in a cellar. In the spring of the following year, open trenches for seedling cultivation, insert the root segments into the trench at a 45-degree angle, with 2 cm exposed above the ground, and water immediately after insertion. If the root segments are treated with rooting hormones and covered with plastic film, the results are even better.

4. Tissue culture

As of 2008, Gansu Province had achieved results in tissue culture seedling cultivation. The Department of Horticulture of Gansu Agricultural University and scientific research extension departments in Wuwei, Jingtai, Jiuquan and other places already possess the technology, equipment and conditions for producing tissue-cultured seedlings.

Through analysis and research on several factors affecting the rapid in vitro propagation of jujube, the most suitable explant for rapid in vitro propagation was selected - the stem segments of young branches from early-spring water culture. The initiation medium was H94 + IBA 0.1 mg/L + NG15 mg/L solid medium with H66 nutrient solution added for solid-liquid two-phase culture. The subculture medium was H66 + NG20 mg/L + IBA 0.1 mg/L. After 30 days of subculture, the average multiplication coefficient was 4. The rooting medium was H94 + NG3-8 mg/L + IAB0.1 mg/L, and the rooting rate was 90%. After 20 days of culture in the tissue culture room, they were placed in a solar greenhouse for another 10 days or so, then the bottle stoppers were opened for hardening off for 3-4 days, and transplanted using the Qinghe sand transitional transplanting method, with a survival rate of up to 96%.

When the test-tube plantlets have grown on the rooting medium for about 20 days, reached a height of 4-6 cm, and have more than three roots, place them in a solar greenhouse for another 10 days or so, open the bottle stoppers for hardening off for 3-4 days, and transplant them into a sterilized seedling bed (the method for the seedling bed is the same as that for the green branch cutting bed in the experimental method). The transplanting depth is 3 cm, and the survival rate can reach 96%.

Using the root system of tissue-cultured seedlings as cutting material makes it easy to survive. In field cuttings, however, the conditions are harsh, and the thickness must reach more than 1 cm and the length 15-20 cm; even with rooting agent treatment, the rooting rate is still very low.

5. Cuttings

Cutting process: Before cutting, first moisten the sand bed. The standard for moistening is that after holes are made in the sand bed, the holes do not collapse. When cutting, use a small wooden stick to make holes in the sand bed while dipping the cuttings in slurry and inserting them. The diameter of the small holes should be larger than the diameter of the cuttings after dipping in slurry, so as to prevent the medicinal solution from being squeezed off by the walls of the small holes and reducing its efficacy. The cutting depth is about 3 cm. Too deep makes it easy to cause basal rot, while too shallow causes the cuttings to fall over and the roots to be exposed after rooting. After cutting, the holes should be pressed tightly so that the river sand and cuttings are closely combined.