2024年5月12日 星期日
乌蕨卵细胞发育的超微结构观察
Ultrastructural observation on egg development of Odontosoria chinensis
2023年 第32卷 第6期 页码[80-86]    下载全文[32MB]  
摘要

为了探究鳞始蕨科(Lindsaeaceae)代表种乌蕨〔Odontosoria chinensis (Linn.) J. Sm.〕的演化地位,采用透射电镜对乌蕨的卵细胞发育过程进行超微结构观察。结果表明:乌蕨的卵细胞发育过程主要包括幼卵、发育卵和成熟卵3个时期。幼卵时期,卵细胞与腹沟细胞以及腹沟细胞与颈沟细胞均通过胞间连丝紧密相连。发育卵时期,在卵细胞和腹沟细胞间形成分离腔,分离腔内含有不定形物质,分离腔自两侧向中央扩大延伸,卵细胞和腹沟细胞中间相连位置为孔区,最后孔区与腹沟细胞分离形成受精孔,受精孔位于卵细胞中央,其分离腔的形成方式较为进化,但受精孔位置较为原始;分离腔中的不定形物质沉积在卵细胞膜表面形成较为进化的网状结构卵膜;并且出现腹沟细胞具2个细胞核和颈沟细胞具4个细胞核的原始现象。成熟卵时期无核外突,表明乌蕨在有性生殖上表现出原始特征。因此,从有性生殖角度看,乌蕨的演化地位较为进化,但有一定的原始性。

Abstract

 In order to explore the evolutionary status of the representative species Odontosoria chinensis (Linn.) J. Sm. in Lindsaeaceae, the ultrastructural observation of egg development process of O. chinensis was conducted by using transmission electron microscope. The results show that the process of egg development of O. chinensis mainly includes three stages namely young egg, developing egg, and mature egg. At young egg stage, egg and ventral canal cell as well as ventral canal cell and neck canal cell are both closely connected via plasmodesmata. At developing egg stage, separation cavity forms between egg and ventral canal cell, the separation cavity contains amorphous substances and extends from periphery to the center, the connection site of cell and ventral canal cell is pore region and pore region is finally separated from ventral canal cell to form. fertilization pore, the fertilization pore is located in the middle of egg, and the formation of separation cavity is more evolutionary, but the location of fertilization pore is more primitive; the evolutionary net structure egg envelope is formed via deposition of amorphous substances in the separation cavity on the surface of egg membrane; the primitive phenomenon of two nuclei in ventral canal cell and four  nuclei in neck canal cell appear. There is no nuclear evagination at the mature egg stage, indicating that O. chinensis shows primitive features in sexual reproduction. Therefore, in terms of sexual reproduction, the evolutionary status of O. chinensis is more evolutionary, but with a certain primariness.

关键词乌蕨; 鳞始蕨科; 卵细胞发育; 超微结构
Key wordsOdontosoria chinensis (Linn.) J. Sm.; Lindsaeaceae; egg development; ultrastructure
作者孙锐1, 包家茜1, 曹建国1, 戴锡玲1, 卫勤2
所在单位1. 上海师范大学生命科学学院, 上海 200234; 2. 上海市奉贤区农业技术推广中心, 上海 201400
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基金项目上海市绿化市容管理局科学技术项目(G152430)