How are grafted Schisandra chinensis seedlings cultivated? A detailed explanation of the key technical points
Schisandra chinensis is a wild fruit tree distributed in Northeast China. Its fruit can be used both as medicine and for brewing wine and making juice to produce beverages. It is a multifunctional, multi-purpose wild economic plant with high development and utilization value and very broad application prospects. Since the 1990s, in response to the continuous decline of wild Schisandra chinensis resources and growing market demand, our institute has carried out research on domesticated high-yield techniques and new variety selection and breeding, summarized a complete set of domesticated high-yield cultivation techniques mainly including artificial orchard establishment, shaping and pruning, soil management, and pest and disease control, and bred the new variety "Hongzhenzhu" and a group of new strains. This achievement has already been promoted on a large scale in the three provinces of Northeast China, and is of great significance for developing genuine medicinal materials of northern China and raw materials for brewing and processing, and for building a distinctive, efficient, and ecological agriculture.
In order to meet the large demand for superior Schisandra chinensis seedlings, the cultivation techniques for grafted seedlings are introduced as follows:
1 Selection of scions
After leaf fall and before germination the following spring, collect 1-year-old branches from superior plants as scions and store them in sand at low temperature; use 1-year-old seedling plants as rootstocks, with a rhizome thickness of more than 0.5 cm; before grafting, soak the reserved rootstock seedlings and scions in clean water for 12-24 hours in preparation for grafting.
2 Grafting
Grafting is carried out by the cleft grafting method during the germination period (late April). For scions, choose branches of moderate thickness that are fully mature, cut them to a length of 4-5 cm, leave 1 bud eye, cut and leave 1.5 cm above the bud, and retain about 3 cm below the bud. The specific method is: use a grafting knife to cut a 3 cm long wedge-shaped slant on both sides of the scion bud eye, and place the cut scions in a basin of water for later use; at the rhizome of the rootstock seedling (below the part where creeping stems are produced), cut off the aboveground part, insert the knife from the center of the cross-section of the rootstock and cut vertically downward about 3 cm to make a cleft opening, select a scion roughly the same thickness as the rootstock and insert it into the cleft opening, ensuring that the cambium on one side is aligned, with the upper end of the cut surface of the scion exposed by 1-2 fen ("exposing the white"), then wrap the graft union of the scion with plastic film strips. The nursery land should be deeply plowed, harrowed fine, fertilized, and ridged.
3 Transplanting
When planting seedlings, handle them gently and place them down gently, and do not let the graft union move. Use a flat hoe to break the ridge and open a 15 cm furrow, apply mouth fertilizer, place the grafted seedlings in the furrow at a plant spacing of 5-10 cm, fill with fine soil, water thoroughly, and then close the ridge. If grafting in place is adopted, the grafting survival rate is higher.
After the grafted seedlings are moved into the nursery, water them promptly when the soil is dry, and frequently hoe weeds and loosen the soil. In mid-June, apply 30-40 g of ammonium nitrate and 10-15 g of potassium sulfate per linear meter of ridge; in early August, apply 40 g of diammonium phosphate and 10-15 g of potassium sulfate.