沙冬青叶肉细胞中一种特殊内含物的发育

DEVELOPMENT OF SPECIFIC INCLUSION IN THE MESO PHYLL CELLS OF AMMOPIPTANTHUS MONGOLICUS

用透射电镜观察了沙冬青（Ａｍ ｍ ｏｐｉｐｔａｎｔｈｕｓｍ ｏｎｇｏｌｉｃｕｓ）叶肉细胞中一种电子密度很高的近似椭圆形的特殊内含物的发育． 它始于中央液泡外侧，起初只是少量的泡状成分和电子密度很高的物质，然后两种成分逐渐增多，并随液泡膜内吞形成突起，不断伸向液泡中央，有的突起占据了液泡很大一部分体积． 接着突起中的泡状成分开始解体，电子密度很高的物质越来越多，直至充满整个突起． 当突起继续内伸时，它的尾部不断收缩变小，最后完全脱离液泡膜而游离在中央液泡里面． 这种内含物一般只出现在严冬季节，里面含有大量的脂．

The development of specific inclusion in the mesophyll cells of Ammopiptanthus mongolicus was observed by means of transmission electron microscopy. The inclusion is approximately oval shaped with very high electron density. It originates from outside of the central vacuole. During its early development it only contains small amount of vesicle like elements and electron dense materials. Then the two kinds of components gradually increase in amount and form a protuberance by endocytosis of the tonoplast. The protuberance becomes larger and larger, sometimes even occupies a great part of the vacuole. Later, the vesicle like elements gradually decrease as the electron dense materials rapidly increase, eventually filling up the protuberance. The protuberance gradually contracts and finally detaches from the tonoplast and immerses freely in the central vacuole. However, such inclusions were never found in small vacuoles. The inclusions usually appear in cold season and contain large quantity of lipid.