彩叶富贵竹叶绿素生物合成代谢的研究

Studies on the Chlorophyll Biological Synthesis in Dracaena sanderiana

[目的]探讨富贵竹色叶形成的生理原因,以便为观赏植物的栽培与育种提供新的试验依据。[方法]以金边富贵竹和银边富贵竹的叶片为材料,对绿叶部分与花叶部分的叶绿素a、叶绿素b、类胡萝卜素、叶绿素合成中间产物含量的变化状况进行分析。[结果]与绿叶部分相比,花叶部分的叶绿素含量显著下降,而类胡萝卜素含量下降幅度较小,2种试验材料表现了相同的倾向;在金边富贵竹的花叶与绿叶部分之间,叶绿素合成中间产物的含量显著不差异,但银边富贵竹花叶部分的Mg-原卟啉含量显著增加,而原脱植基叶绿素a显著降低。[结论]总叶绿素缺乏是引起富贵竹彩叶形成的主要原因,在金边富贵竹花叶部分的叶绿素合成代谢中由原脱植基叶绿素a转化为叶绿素a、或叶绿素a转化为叶绿素b的过程受到了阻抑,而在银边富贵竹中由Mg-原卟啉转化为原脱植基叶绿素a的过程受到了阻抑。

[ Objective ] The research aimed to explore the physiological reason of the etiolated leaf in Dracaena sanderiana, for providing the experimental basis for cultivation and breeding of ornamental plants. [ Method] The content changes of the chlorophyll a, chlorophyll b, carotenoids and intermediates products during chlorophyll synthesis in green and etiolated leaves have been analyzed by using Dracaena sanderiana cv. Virescens and Dracaena sanderiana for materials. [ Result] The same tendency of two tested materials showed that the contents of chlorophyll in etiolated leaves dropped significantly while the contents of carotenoids did not change so obviously compared with green leaves. On the other hand, the different variation of two materials manifested in the following aspect： the content of intermediates products during chlorophyll synthesis had no significant difference between green and etiolated leaves in Dracaena sanderiana cv. Virescens, but the content of Mg-proto- porphyrin increased markedly while pretochlorophyllide a decreased in Dracaena sanderiana. [ Conclusion ] It was suggested that the deficiency of total chlorophyll was the main reason for etiolated leaves formation. The metabolic block maybe emerges in the synthesis pathway from proto- chlomphyllide a to chlorophyll a, or chlorophyll a to chlorophyll b in Dracaena sauna cv. Virescens, but from Mg-protoporphyrin to proto- chlomphyllide a in Dracaena sanderiana.