| The main contents of this experiment were as follows:establishment of rapid rapid propagation in vitro of Honghuashantao(Prunus davidiana (carr.) Franch var.), Zhubo5(Prunus persica var.) and Guanghetao(Prunus mira Koehne); establishment of efficient regeneration system in vitro of Honghuashantao (P. davidiana (carr.) Franch var.), by using its hypocotyls, cotyledons, leaf from proliferation, and leaf from regeneration as explants; changes of the endogenous hormones during regeneration. The main results were described as follows:1. Stems of Honghuashantao, Zhubo5and Guanghetao were used as explants in this study. The best disinfection method chosen was infiltrating the explant with75%of alcohol for30s, then treated with0.1%HgCl2+0.01%Tween for7min, and washed with water for6times Higher percentage of bud germination was found when explants of Honghuashantao and Zhubo5were sampled on March to April, and April to May respectively. but for Guanghetao, no significant difference of bud germination was found when sampled from March to May. According to the results of proliferation medium selection, similar optimal medium,LP+6-BA1.0mg/L+IBA0.2mg/L, for proliferation of Honghuashantao and Guanghetao was found. While different medium for Zhubo5, MS+6-BA2.0mg/L+IBA0.2mg/L, was selected. The shoots could grow healthily and proliferate rapidly in these selected medium, and more shoots were proliferated when the transplantation times of the shoots increased. The rooting medium selected for Honghuashantao and Guanghetao was1/2MS+IAA1.0mg/L+NAA1.0mg/L. No adaptable rooting medium was selected out for Zhubo5because of its less rooting ability.2. Efficient regeneration system in vitro of Honghuashantao (P. davidiana (carr.) Franch var.) was established in this experiment by using the hypocotyls, cotyledons, leaf from proliferation, and leaf from regeneration as explants found here. No significant difference of hypocotyls regeneration was found. Hypocotyls’ morphology upper part has the higher ability of regeneration. Hypocotyls of Honghuashantao were placed onto shoots induction medium LP+TDZ3.0mg/L+NAA0.1mg/L, followed by a7days initiall culture in darknesson, then transferred to light culture. A maximum of46.53%shoots showed multiplication. Cotyledons of Honghuashantao were placed onto shoots induction medium MS+TDZ4.0mg/L+NAA0.5mg/L, follow by21days of pre-culture, A maximum of30.76%shoots showed multiplication. Using the leaf from proliferation of1.0-2.0cm as explant, inoculated on LP+TDZ3.5mg/L+IBA0.05mg/L+Glucose30g/L with abaxial axial contact medium, followed by a21days initiall culture in darknesson, then transferred to light culture on medium without auxin LP+TDZ3.5mg/L, the highest regeneration frequence and average number of adventitious shoots per leaf were found to be29.70%, and1.87respectively. Using the leaf from regeneration1.0-2.0cm as explant, inoculated on LP+TDZ3.5mg/L+NAA0.05mg/L+Glucose30g/L with abaxial axial contact medium, followed by a21days initiall culture in darkness, then transferred to light culture on medium without auxin LP+TDZ3.5mg/L, the highest regeneration frequence and average number of adventitious shoots per leaf were found to be36.34%and2.18respectively.3. Because the explants of peach were difficult to regenerate adventitious buds during in vitro culture, we studied the contents of endogenous hormones in explants at different developing stages to explore the relation between adventitious bud differentiation and endogenous hormones and factors that limit the formation of adventitious buds. Use of enzyme-linked immunosorbent assay (ELISA) revealed that, the amount of endogenous hormones varied among peaches, and those which had high amount of endogenous hormones grew and propagated quickly. The combined function of GA and IAA could promote callus growth. The differentiation of adventitious buds was tightly related to the ratio of ZR to IAA, high rate of ZR/IAA was favorable to bud differentiation. |
PDF Full Text Request