Hardwood cleft grafting method for asexual propagation and seedling raising of Schisandra chinensis

After leaf fall and before bud break, collect 1-year-old branches as scions; before the ground freezes, lift 1- to 2-year-old seedling stock as rootstock, and store them at low temperature for cleft grafting during the next year's bud break period (or graft in place without lifting the seedlings). Before grafting, soak the scions and rootstocks in clean water for 12 hours. Cut off the bud-bearing portion at the hypocotyl of the rootstock. For scions, choose fully mature branches with a diameter greater than 0.4 cm, cut them to a length of 4-5 cm, keep 1 bud eye, leave 1.5 cm above the bud, and keep about 3 cm below the bud; use a grafting knife to cut down on both sides of the scion bud eye, making a wedge-shaped cut surface about 1-1.5 cm long. Wrap the prepared scions in a clean wet towel to prevent water loss.undefinedundefinedundefinedundefinedundefinedundefinedundefinedundefinedundefinedundefinedundefinedundefinedAccording to the length of the scion cut surface, make a cleft about 2 cm deep at the center of the rootstock, select a scion of roughly equal thickness and insert it into the cleft, ensuring that the cambium aligns on one side. Generally leave 1-2 mm of the scion cut surface exposed ("bai"). Then tie the entire graft union tightly with plastic film. Transplant the grafted seedlings into the nursery at a spacing of 5 cm x 20 cm. To prevent the scions from losing water and drying out, the upper cut end of the scion can be sealed with lead paint. After transplanting, callus tissue forms in 10-15 days, and sprouting can occur after 30 days. When about 30% of the grafted seedlings have sprouted, shade should be provided, because at this time the callus tissue of the scion and rootstock has not yet fully connected, and the water absorbed by the root system cannot well supply the needs of the scion; this can prevent large-scale death of scions from water loss caused by high temperature and sun exposure. When the new shoots begin to elongate and grow, pinching treatment is needed, generally leaving 2-3 leaves is more appropriate. When the temperature exceeds 30°C, water can be sprayed on the leaves to lower leaf temperature and reduce transpiration. When the new shoots sprout secondary shoots and begin second growth, it indicates that the grafting has survived, and the shading material can be removed.