Studies On Hard Wood Cutting Propagation Technology And Rooting Mechanism Of Liriodendron Chinese×L.tulipifera

This article is aim to study hard wood cutting propagation technology and rooting mechanism of Liriodendron chinese×L.tulipifera by its la branch.The main results are as following:(1)Cuttings from basel hard branch would be benefit for propagation than which from middle and upper hard branch with their rooting rate reached to 81.1%.(2)The results indicated that exogenous hormones took great effects on cutting propagation. The timespan of callusogenesis for hard wood cutting treated by NAA with 1000mg·L-1 for 60s was the shortest, which was 29d. Another, the timespan of rooting for hard wood cutting treated by IBA with 1000mg-L-1 for 60s was the shortest, which was 47d. Third, the rooting rate for hard wood cutting treated by NAA with 1000mg·L-1 for 60s was the highest, which reached to 72.4%.(3)Cuttings which were kept in cold storage with 0～5℃for 45d would achieve the better results, with their rooting rate reached to 70.2%. Their callus appeared in 28d and rooting in 35d after sticking. Bud picking was demonstrated could took great effects on cutting propagation The results showed that the cuttings picked buds would cullusing and rooting in 39d and 52d respectively after sticking, and their rooting rate reached to 68.9%.(4)The study of rooting mechanism indicated that some indexes which about the contents of nutrient such as soluble sugar, amylum and soluble protein revealed a given rule with the development of rooting, and much nutrient substance were consumed. The activity of SOD, POD and PPO was related to rooting significantly. More specifically, stronger activity of SOD and higher contents of MDA would restrain rooting, while strong activity of POD would be of advantage to rooting. Moreover, PPO could be in favor of the induction of root primordium and play an important role in rooting.(5)IAA could promote the formation of callus at low concentrations and promote rooting at higher concentration. ABA would restain rooting but could enhance the stress resistance of cuttings. Accumulation of GA3 and ZR in cuttings would contribute to callusogenesis.