冬季沙冬青细胞质中一种高电子密度结构的电镜观察

用透射电子显微镜观察了冬季沙冬青的叶肉细胞。观察表明,其细胞质中有一种电子密度很高的结构,分布广,主要位于有一定解体现象并含有较多嗜锇小球叶绿体附近,有的甚至与叶绿体被膜贴在一起,很少存在于发育良好的叶绿体附近和液泡中。其大小不同,通常为椭圆形,有时也近似圆形。表面没有包围膜,泡状结构少,常有突起。这种结构的电子密度很高,染色较均匀,冬季大量出现可能与提高植物的抗寒性有关.

Electron microscopic observation on electron-dense structure in cytoplasm of Ammopiptanthus mongolicus

Transmission electron microscopic observations on the mesophyll cells of Ammopiptanthus mongolicus showed that in winter time, there was a kind of electron dense structure widely distributed in cytoplasm. This kind of structure mainly located around the chloroplasts which had generally been disintegrated and had many osmiophilic globuli. Some of this structure even pasted with chloroplast envelope membranes, and few existed in well developed chloroplasts and vacuoles. The structures were different in size, usually ellipsoidal shaped or semicircular shaped. The surface of the structures did not possess a layer surround membrane and vesicular shaped structures, but a few of radiate protuberances. The structures were very dark in electron dense and their staining was quite even. The formation of a great quantity of the structures may be related with increasing coldness resistance of plants.