Abstract: The early period of symbiotic growth in the Acacia glauca nodule cells is characterized by an increase in the number of rhizobia-bac-teroid and host cytoplasm and organelles. The bacteroids increase by fission until they occupy most region of host cytoplasm. Surrounding bac-teroid membrane envelopes contain one or more bacteroids. The late period of symbiotic growth involves changes in the structure of bacteroid cells as well as the number of host cell organsllos. The symbiotic nitrogen fixation of the nodules is also discussed.

Key words: Acacia glauca nodules, Bacteroid cell fission, Host organel-les, Ultrastructure

摘要： 根瘤细胞早期发育阶段,以宿主细胞器和根瘤菌转化类菌体的数量增多为特征。随后类菌体增殖到填满宿主细胞内的大部分区域。各个类菌体周膜内含有1至几个类菌体。晚期共生发育阶段,类菌体细胞结构和宿主细胞器数量发生了变化。文中还讨论了根瘤的共生固氮作用。

关键词: 灰金合欢根瘤, 类菌体细胞分裂, 宿主细胞器, 超微结构