榕樹皮孔發育過程中微細構造的研究

Ultrastructural Study on the Development of Lenticels of Ficus microcarpa L. f.

本文研究榕樹枝條上皮孔發育過程中微細構造的變化。皮孔內尚存活的前充塞細胞、填充細胞、皮孔形成層細胞與封閉層細胞均含有大液胞、細胞核、粒線體、色素體與高爾基體。皮孔分化與發育過程中封閉層細胞、前充塞細胞與填充細胞的細胞壁均會漸漸地木栓化。以電子顯微鏡觀察木栓化的細胞壁可看到層狀的構造。成熟封閉層細胞之木栓化的外切面細胞壁與初生細胞壁分離，而在其液胞內具有纖維狀片段。酸性磷酸酶的次細胞分布，主要是在細胞壁及液胞內近液胞膜處，而在封閉層細胞則只分布於胞間連絲。

The ultrastructural changes of lenticels on the branches of Ficus microcarpa L. f. during the developmental stages were studied. All the living precomplementary cells, complementary cells, and cells of the lenticel phellogen and the closing layer contained a large vacuole, nucleus, mitochondria, plastids, and dictyosome. During the differentiation and maturation of the lenticels the cell walls of the closing layer, precomplementary cells, and complementary cells were progressively suberized. The electron microscopic examination of the suberized layers in the cell walls showed lamellar appearance. The suberized outer tangential walls of the mature cells in the closing layer were found to be separated from their primary walls, and in the central vacuole fibrous fragements were observed. The subcellular localizations of acid phosphatase were mainly distributed in the cell walls and vacuoles near the tonoplast In the closing layer, acid phosphatase was detected only in the plasmodesmata.