Systemic Study On Rapid Propagation Technology Of Platanus Acerifolia

In order to promote quickly new species in Platanus acerifolia, improving ecological environment of urban, with different clone of Platanus acerifolia as material, adopting branching and bud grafting technology, the experiment was done;,The softwood cuttings propagation for three yeas old has been done, with softwood cutting of Platanus acerifolia as material , softwood cutting was treated with different cutting way and different concentrations and times, several endogensis hormone included AuxinIAA,abscisic acid ABA, cytokinin ZR and gibberelin3 GA₃with cutting and their mother trees were analyzed by using the enzyme-linked immunosorbent assays(ELISA) technique, The tissue culture experiment was done with sprouting branching of dormant branching as explants ,Effect of grafting way and different clone to survival grafting, and effect of different cutting time and cutting way to survival of softwood cutting in Platanus acerifolia, and effect of ABT1 to the survival of softwood cutting in Platanus acerifolia, the change of endogensis hormone during rooting process and their mother tree, and developing tissue culture technique were studied. The main conclusion shows as follow1) The survival rate of branching grafting higher than that of budding grafting in grafting experiments; clones of 4 and 7 is better in graft survival and growth..2) The best period of softwood cutting is in late May to late June in Platanus acerifolia; the best cuttings way is preserving lower leaf and internodes on May 20; the best cuttings way is preserving higher leaf and internodes and preserving lower leaf and node on June 5; the best cuttings way is preserving higher leaf and internodes or preserving lower leaf and internodes on June 20.3) There was differences between effects of ABT1 rooting powder to the survival of softwood cutting in different cutting time in Platanus acerifolia; there is no effecting in effects of ABT1 rooting powder to the survival of softwood cutting on May 20 and July 10; there is obviously effecting in effects of ABT1 rooting powder to the survival of softwood cutting on June 5 and June 20, the effect of different cutting way to the survival of softwood cutting is obvious. The 300mg/L of ABT1 rooting powder is not only increasing survival rate of softwood cutting on June 5 and June 20, but also advancing root length and doing not restrain elongation and leaf number of softwood cutting seeding, the best cuttings way is preserving higher leaf and internodes on June 20; effects of time of ABT1 rooting powder to the survival of softwood cutting is not obvious. The best treatment of experimentation is 300mg/L- preserving higher leaf and internodes-5s, the survival rate of this treatment is ninety three point three percentages. 4) The change IAA, ZR and ABA content of leaves is higher, different parts of GA₃ content higher than the ZR, ABA and the IAA, ZR and ABA content higher than the IAA, after June, the IAA, ZR and ABA content of leaves is basically slightly higher than the top, node and internodes. Before June, in addition to the IAA content of top and internode, endogensis hormone content of different parts is quickly increased, then starting reducing, endogensis hormone content of different parts have no bigger change from June to Angust, excluding the IAA and ABA content, After Mid-Angust, The IAA, GA₃, ZR and ABA content of leaf and top was increasing, but the IAA, ZRand ZR content was reducing, excluding ABA. 5) The relationship between IAA,GA₃,ABA,IAA/ZR and survival rate are close, The lower content of IAA can promote rooting, but the higher content of IAA inhabit rooting, higher content of GA₃ and ABA inhabit rooting, the ratio of IAA and ZR is low, the survival rate is high. The IAA content of 151.3 ng.g^-1.fw^-1 and GA₃ no higher than 8337.5 ng.g^-1.fw^-1 are suitable for cutting to survive, The cuttings has entered dormant In mid-July, at this time Lignifications is the key factor of cuttings survival rate. 6)According IAA / ABA and the IAA / ZR as choosing cutting way indexes, the ratio of IAA / ABA and the IAA / ZR of internode is higher than node, the survival of preserving upper leaf and internode is higher than preserving upper leaf and node from May20 to June 20, vice versa, but the trend of preserving upper leaf is opposite for preserving lower leaf, the ratio of IAA / ABA and the IAA / ZR of internode is higher than node,the survival rate of preserving lower leaf and node is higher than preserving lower leaf and internode,in July,but the survival rate of preserving lower leaf and internode is higher than preserving lower leaf and node in Angust. 7) Ten day after cutting is the critical period of survival, higher IAA inhibit cutting healing, lower IAA do not promote wound healing, there must be an appropriate concentration, and the cutting IAA content of 214 ng.g^-1.fw^-1 was suitable for the cutting healing, boosting ZR content can promote the cutting healing. Ten day-twenty day is critical period of root growth, higher IAA inhibit the length of root, but lower content of IAA promote the length of root, the appropriate content is 90.8 ng.g^-1.fw^-1,ZR is the main endogensis hormone of promoting the length of root, higher content of ZR can boost the length of root, however, the higher content of ABA can inhibit the length of root, Twenty day-forty day is the crucial period of increasing root number, increasing content of ZR can increase root number in the early time, IAA is the main factor of boosting rooting in after time, the lower content of ZR can increase the number of root.8) The results indicated that the best sterilization way for explants were 75%, ethanol10s+0.1% HgCl₂ 8min, 75% ethanol 10s +0.1%HgCl₂10min+ 75% ethanol 20s+0.1% HgCl₂ 6 min; Induction buds of the optical medium was MS+IBA 0.2mg/L+6-BA 0.5 or 1.0 mg/L, induction buds percentage was one hundred percentage, MS + IBA 0.1 mg/L + 6-BA1.0mg/L was the best bud proliferation, bud proliferation coefficient was 3.5,the best of rooting medium was 1/2 MS+IBA 0.1mg/L,rooting coefficient is one hundred percentage.