Study on Cutting Propagation of Robinia pseudoacacia Clones

Study on cutting propagation technology of black locust clones was carried out in Henan province in order to improve the qualified rate of seedlings. Survival rate, qualified rate, ground diameter and height of seedlings was studied under diameter and length of root segments and planting methods, obtained the following results and conclusions: The ground diameter of clonal seedlings by three planting methods including buried, oblique cuttage and vertical cuttage was the same. The seedling height planted by vertical cuttage increased 11.5% and 4.5% respectively than that by buried and oblique cuttage, and the survival rate of seedlings by buried was significantly lower 10.45%11.23% than that by oblique cuttage and vertical cottage. Different diameter and length of root segments had great influences on survival rates but had no influences on growth for clonal seedlings. The diameter and height of root segments was larger, the survival rate and qualified rate of clonal seedlings was higher. Using root segments that diameter was larger than 0.5 cm, length was 10 cm to propagation, it could obtain much higher qualified rate which was about 60% at the end of growing season. Using root segments that diameter was larger than 0.5 cm, length was 8 cm to propagation, the qualified rate was about 50%. Using root segments that diameter was less than 0.5 cm, length was less than 6 cm to propagation, the qualified rate was lower than 40%. Therefore, for cutting propagation of black locust clones, should use vertical cuttage, and length and diameter of root segment should be more than 0.8 cm, and 0.5 cm, in this way, the qualified seedling can reach more than 50%.