花椒果实分泌囊发育过程的超微结构研究

电镜观察结果表明,花椒(Zanthoxylum bungeanum Maxim.)果实分泌囊是由裂生方式形成,由鞘细胞、上皮细胞和油腔构成。对分泌囊的原始细胞、油腔发生和扩大以及发育成熟3个时期的超微结构研究表明,其精油是在分泌囊油腔发生时开始积累,以油滴形态存在于上皮细胞的质体内及其周围的细胞质中。根据各细胞器的变化规律分析,质体是精油合成的主要场所,内质网参与精油的合成和转运,线粒体为上述活动提供能量。上皮细胞内积累的精油可能通过两种途径排出细胞,分泌至油腔内贮存。鞘细胞内也积累精油,其主要合成场所也与质体有关,以后转运至上皮细胞内。成熟分泌囊的质体由于功能改变,其内出现蛋白质结晶和淀粉粒。

ULTRASTRUCTURE OF THE SECRETORY CAVITY DEVELOPMENT IN THE FRUIT OF ZANTHOXYLUM BUNGEANUM

It was proved by electron microscopic observation that the secretory cavity which was found to be formed schizogenously was consisted of an oil chamber lined with epithelial cells and sheath cells in the fruit of Zanthoxylum bungeanum Maxim. The ultrastrueture of the secretory cavity in different stages of development showed that the essential oil started to be accumulated in the oil chamber when it appeared in the form of oil droplets in the plastids and cytoplasm of the epithelial cells. Based on the character of changes in various organelles, the authors inferred that the plastids were the main organelle where oil was synthesized. Endoplasmic reticulum participated in the process of oil synthesis and oil transportion, while mitochontrion was the energy provider. It seems that oil droplets were synthesized by the plastids in the sheath cells and were transported to the epithelial cells where oil was accumulated. The epithelial cells then excreted the oil droplets in two ways into the oil chamber for accumulation. In the mature secretory cavity owing to the functional change of the plastids, protein crystals and starch grains were also found in the plastids.