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

Liriodendron chinese×L.tulipifera belongs to Liriodendron genus of Magnoliaceae family, it is an excellent commercial and ornamental tree species. In order to meet the needs of nursery stock and provide the technological basis for effective cultivation and utilization of Liriodendron chinese×L.tulipifera,we studied the cutting propagation technology and rooting mechanism of Liriodendron chinese×L.tulipifera. The following results were documented:The results of cutting propagating experiment showed external hormone played an important role in rooting of plant significantly, and the effect of NAA+IBA(1:1) powder was the best, the rooting rate for softwood cutting treated by NAA+IBA(1:1) with 1000mg·L-1 for 30s reached to 76%; the cutting propagating was better at the time of the middle of June approximately; cuttings come from upper to middle shoots would be benefit for the propagation .The studying of rooting mechanism indicated that some indexes about the contents of nutrient manifested a given rule with the development of rooting, such as soluble sugar, amylum, soluble albumen, total nitrogen, total phosphor and the ratio of C/N etc. During adventitious root formation, most of the content of nutritive substance declined with the emergence of cullusing and rooting. The content of nutritive substance of cuttings treated with ABT6 was higher than CK; the ratio of C/N manifested the rooting ability in some extent, the higher ratio of C/N of softwood cuttings was favorable to root.IAA, ABA, GA3 and ZR had different change rules during rooting process. The contents of IAA, GA3 and ZR in soft wood cuttings are positively correlated with rooting rate, the contents of ABA is negatively correlated with rooting rate, the changes of IAA content were contrary to ABA, The ratio of IAA and ABA can be as a scale estimating softwood cutting rooting capacities, it is favor that there is the high ratio of IAA/ABA advantaged the rooting process.The experiment of the activity of POD and PPO indicated that the activity of POD and PPO correlated with rooting significantly. The activity of POD had two peaks during rooting process; the activity of PPO increased gradually during the root primordial inducement and morphogenesis. The exogenous ABT6 could increase the activity of POD and PPO of cuttings.