摘要
采用透射电子显微镜、组织化学和荧光显微镜相结合的方法对华南忍冬(LoniceraconfusaDC.)不同发育阶段的花结构差异及其绿原酸积累规律进行系统分析。结果显示:随着花的发育,花冠筒叶绿体结构逐渐完善并积累淀粉粒,幼蕾期叶绿体已有基粒和基粒片层出现,但没有明显的淀粉粒出现;绿蕾期叶绿体结构完整,积累有一至数个淀粉粒;白蕾期叶绿体数量少,含有丰富的淀粉粒;银花期和金花期叶绿体极少;花冠筒木质部导管细胞壁逐渐木质化加厚。在花冠筒中,幼蕾期和绿蕾期绿原酸含量丰富;白蕾期薄壁细胞内绿原酸含量开始减少,维管束仍积累较多的绿原酸;银花期和金花期薄壁细胞绿原酸含量进一步减少且分散分布,维管束累积的绿原酸也减少,主要分布在木射线中。在花萼筒—子房中,不同发育阶段,其薄壁细胞、维管束、中轴胎座和胚珠都有绿原酸分布。表明绿原酸可能在叶绿体内合成,然后转至细胞液中聚合,最后在液泡内积累;叶绿体中淀粉粒数量与绿原酸合成呈负相关。
Lonicera confusa is the main source plant producing lonicerae flos in South China. In the present study,transmission electron microscope（TEM）,histochemical methods and fluorescence microscope were employed to investigate the ultrastructure and accumulation law of chlorogenic acid in Lonicera confusa flower at different developmental stages. The results showed that,with the development of the flower,the structure of chloroplast in corolla tube gradually became perfect,and the starch grains began to accumulate in the chloroplast. The grana and grana lamella appeared in the chloroplast with no starch grain at the stage of young alabastrum. The chloroplast with perfect structure at the stage of green alabastrum accumulated one or numbers of starch grains. A small amount of chloroplasts containing abundant starch grains existed at the stage of white alabastrum. At the stages of silvery and golden flower,there was nearly no chloroplast in corolla tube. Lignification gradually thickened in the cell wall of vessels in the xylem of corolla tube.Abundant chlorogenic acid accumulated in the corolla tube at the stages of young and green alabastrum. The chlorogenic acid content in parenchyma cells at the stage of white alabastrum began to decrease,with relatively high level of chlorogenic acid accumulation in vascular bundle. The chlorogenic acid content in parenchyma cells at the stages of silvery and golden flower further decreased,with scattered distribution. The chlorogenic acid accumulation level in vascular bundle began to decrease,with the main distribution of chlorogenic acid in the xylem ray. Additionally,the chlorogenic acid was examined to be distributed in parenchyma cells,vascular bundle,axial placentation,and ovule in the calyx tube-ovary of the flower at different developmental stages. The present study demonstrates that chlorogenic acid is biosynthesized in the chloroplast,transferred to cytoplasm,and finally accumulated in the vacuole. The number of starch grains in the chloroplast is negatively related with the biosynthesis of chlorogenic acid.
出处
《园艺学报》
CAS
CSCD
北大核心
2012年第11期2206-2216,共11页
Acta Horticulturae Sinica
基金
国家自然科学基金项目(30800077)
广东省自然科学基金项目(5006633)
关键词
华南忍冬
发育阶段
花超微结构
绿原酸
积累规律
Lonicera confusa DC., developmental stage, flower ultrastructure, chlorogenic acid, accumulation law
