| Bothrocaryum controversum Hemsl. belongs to the Cornaceae, is a good ornamental tree of landscape application prospect. With hard and dense seed coat and long seed dormancy, Bothrocaryum controversum Hemsl.'s seedlings propagation from seed is complex, but it is mainly propagated from seed. Therefore, it was necessary to establish the system of micropropagation of Bothrocaryum controversum Hemsl. The emphasis of this thesis was to establish the system of micropropagation of Bothrocaryum controversum Hemsl. for rapid propagation and genetic transformation. The major results were as follows:1. The explants were the apical buds of 1-year branch. They were surface sterilized with 20% 84 disinfectant solution for 15min. The optimum induction medium was Woody plant medium (WPM) supplemented with 0.5mg/L 6-benzylaminopurine (BA), 0.2mg/L indole-3-butyric acid (IBA) and 1mg/L gibberellin (GA3).2. The highest shoot proliferation rate of 4.4 times was obtained on the medium M (the concentration of CaCl2·2H2O in Murashige and Skoog (MS) medium was 1200mg/L) supplemented with 1mg/L BA, 0.2mg/L IBA and 2mg/L GA3.3. Vitrification was one of the problems which affected the growth of microshoots. Plant growth regulators(PGRs), AC, sucrose, agar with different densities were studied in this experiment, the results showed that, supplementing with 0.1mg/L AC, decreasing the concentrations of the PGRs and increasing the concentrations of sucrose and agar, vitreous shoots could change to normal ones.4. 1/2M medium with 3mg/L IBA was the optimum shoot rooting medium, on which the shoots cultured 10 days in dark then transferred to the light condition had the highest rooting efficiency (60.0%).5. The optimum medium for transplant was vermiculite.perlite1 :1 (volume ratio), the survival rate was up to 70.0%.6. The optimum medium for callus induction from leaves of microshoots is MS supplemented with BA 0.5mg/L and NAA 0.2mg/L, where 100% of cultured leaves produced callus and grew well. The calli were loose, soft and off-white to greenish. Basal section of leaf responded better than middle section and apical section in terms of callus induction efficiency and growth performance. |
