Studies On The Cutting Propagating Technology And Rooting Mechanism Of Toona Ciliata Var. Pubescens

Toona ciliata var.pubescens, a broadleaf tall tree species, belongs to Toona genus of Melialeae family. It had the" The Chinese mahogany "reputation in the international market, and had been listed as the state-protected the second class rare and endangered plants by the state. Based on Toona ciliata var. pubescens materials in this paper, the cutting propagate technology and rooting mechanism were researched and discussed, so as to expand it’s breeding methods and means, provide some theories and evidences for establishing good asexual nursery system.The main conclusions were as follows:1、Through the experiment of the different types of cuttings to the rootings of Toona ciliata var. pubescens。The results showed that:the rooting rate、the longest root length、new sought length and new sought parameters to root cutting>hardwood cutting> softwood cutting、root efficiency index to hardwood cutting> root cutting> softwood cutting, and the rooting rate of hardwood through the winter storage>the hardwood of none storage. The variance analysis showed that:The rooting rate of the root cutting75.23%was significant the softwood of36.84%; The root efficiency index of hardwood cutting2.80was significant with the index of root and softwood of2.03and1.75; The longest root length of root cutting21.00cm was significant with the softwood of15.45cm; The new sought length of the root cutting18.80cm was significant with the hardwood and softwood of16.00cm and15.60cm; The rooting rate of hardwood of could be improved significantly under the winter storage. Rooting rate was75.25%higher than that of70.65%with no storage.2、Using exogenous hormones treatment the root of cuttings was improved significantly. The rooting rate of root cutting upped to82.81%under the management of200mg/L IBA, more than CK54.98%increased by27.83%; and that of hardwood cutting upped to77.93%, more than CK45.02%increased by32.91%. There were significant differences among different growth regulator, showing IBA> ABT6>NAA>CK. And there also had significant differences with the longest root length, root efficiency index and new sought length among the treatments.3、Using the different substrates type (yellow soil、perlite、yellow soil:perlite (2:1)、yellow soil:sand (2:1)); different hormone type (IBA、NAA、ABT6、IBA: NAA(1:1)); different hormone treatment (500mg/L soaking4h、100mg/L soaking2h、250mg/L soaking0.5h、400mg/L10s) for root and hardwood cutting, The orthogonal experiment results showed that:The best root effect of root and hardwood cutting was the250mg/L IBA soaking0.5h then cutting in yellow soil:sand (2:1), rooting rate upped to87.90%、86.73%, and the root efficiency index upped to2.25、 2.90.4、Using the different substrates type A (yellow soil、yellow soil:perlite (2:1)、 yellow soil:sand (2:1)); different hormone type B (IBA、ABT6、IBA:NAA(1:1)); different hormone treatment C (50mg/L soaking3h、100mg/L soaking1h、200mg/L soaking0.5h) for softwood cutting. The orthogonal experiment results showed that:The best root effect of softwood cutting was100mg/L IBA soaking one hour then cutting in yellow soil: sand (2:1), rooting rate upped to41.26%, the root efficiency index upped to0.95.5、Through the physiological indexes in the process of cutting of hardwood cutting were experimented, the results show that:The contents of soluble sugar, starch and soluble and the activity of POD and PPO in hardwood cuttings were positively correlated with the rooting rate. The contents of soluble sugar, starch and soluble protein were changing during rooting process. Lots of nutrient materials were consumed during the root formative period. The activity of POD increased before the adventitious form, then declined gradually in the root formative period but picked up slightly during the root elongating period. The activity of PPO increased gradually during the root primordia inducement and morphogenesis, with the elongation of adventitious root, the activity of PPO declined gradually.250mg/L exogenous hormones IBA could boost the activity of POD and PPO, so as to shorten the rooting time of cuttings.6、Through the experiment of inhibiting things in hardwood of Toona ciliata var. pubescens. The results showed that:There existed some materials which influenced and inhibited rooting of cuttings in hardwood phloem of Toona ciliata var. pubescens. relatively higher in the basal part cutting. The higher of soaking concentration, the lower of sprouting rate of white rapeseed, when more than50%, the ability of rooting dropped quickly.7、The external morphology of hardwood cutting in rooting process was observed, Discovering both the callus and skin department can taken root, so the rooting type of Toona ciliata var. pubescens is a mixed type.