宜昌润楠（Machilus ichangensis)属樟科（Lauraceae)润楠属（Machilus)植物，常绿乔木，是中国传统的珍贵优质用材树种。对宜昌润楠的大、小孢子发生及雌、雄配子体发育过程进行了详细的细胞学观察。结果表明，宜昌润楠的雌蕊子房1室，单胚珠，倒生，双珠被，厚珠心。大孢子母细胞经减数分裂形成直线形排列的4个大孢子，合点端的发育成功能大孢子，其余3个退化，胚囊发育类型为蓼型。雄蕊花药多为二室，少三室、四室花药，变形绒毡层，小孢子四分体排列为四面体型，成熟花粉为二胞花粉。小孢子有少量败育及不育现象，雄性不育株绒毡层细胞延迟降解，使小孢子得不到营养而不能正常发育，最后败育。%Machilus ichangensis Rehd.et Wils is an unique high-quality timber species belonging to Lauraceae Machilus. The megasporogenesis,microsporogenesis and development of male and female gametophytes in the flower of Machilus ichangensis were observed at cellular level. The results showed that the ovary of Machilus ichangensi had 1-locules,with single ovule.The ovule was anatropous,bitegmic and crassinucellate with the endothelium.The megaspore mother cell formed a linear tetrad of 4 megaspores after meiosis. The chalazal megaspore developed the functional one and the other 3 at the micropylar pole were degraded. The development of embryo sac was of polygonum type. There were 2-locules,3-locules and 4-locules anther sac in flowers. The tapetum was amoeboid. The microspores tetrad was arranged in a tetrahedral. The mature pollen grains were of 2-celled types. There were little pollen abortion and male sterility since the tapetum of male sterile plants delayed degradation and the microspores could not obtain enough nutrition for normal development.
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