欢迎访问《植物研究》杂志官方网站,今天是 分享到:

植物研究 ›› 2024, Vol. 44 ›› Issue (1): 27-33.doi: 10.7525/j.issn.1673-5102.2024.01.005

• 系统与进化 • 上一篇    下一篇

砂引草(紫草科)大小孢子发生和雌雄配子体发育及其分类学意义

孙豪愽, 孔冬瑞(), 胡德昌   

  1. 鲁东大学生命科学学院,烟台 264025
  • 收稿日期:2023-07-03 出版日期:2024-01-20 发布日期:2023-12-27
  • 通讯作者: 孔冬瑞 E-mail:drkong@163.com
  • 作者简介:孙豪愽(2001—),男,本科生,主要从事植物生殖生物学研究。
  • 基金资助:
    鲁东大学博士启动基金(LY2015014);山东省省委省政府重点项目(鲁财预指[2021]1号);山东省重点研发计划(重大科技创新工程)项目(2021LZGC023)

Sporogenesis and Gametogenesis of Messerschmidia sibirica L.(Boraginaceae) and Their Taxonomic Implications

Haobo SUN, Dongrui KONG(), Dechang HU   

  1. College of Life Science,Ludong University,Yantai 264025
  • Received:2023-07-03 Online:2024-01-20 Published:2023-12-27
  • Contact: Dongrui KONG E-mail:drkong@163.com

摘要:

砂引草属(Messerschmidia L.)在紫草科(BoraginaceaeJuss.)分类系统里位置不稳定,为更好地理解砂引草属的分类学位置,利用常规石蜡制片技术结合光学显微镜观察了砂引草(Messerschmidia sibirica L.)的大小孢子发生及雌雄配子体发育特征。结果如下:(1)花药4室,成熟花药壁由表皮、药室内壁、1层中层和绒毡层共4层细胞构成,双子叶型花药壁发育类型,分泌型绒毡层,成熟绒毡层细胞含2核,表皮宿存,药室内壁不规则2层,具纤维性加厚;(2)小孢子母细胞减数分裂过程中胞质分裂为同时型,小孢子四分体四面体型排列,成熟花粉粒为2-细胞型;(3)胚珠倒生,单珠被,珠孔狭长,具珠被绒毡层,假厚珠心,部分珠心组织宿存至成熟胚囊时期;(4)胚囊发育类型为蓼型,成熟胚囊梭形,极核在受精前融合,反足细胞退化早。砂引草胚胎学特征与天芥菜属(Heliotropium)其他种类胚胎学特征十分相似,稍有不同,鉴于胚胎学特征在属内较为稳定,支持分子系统中将砂引草属置于天芥菜属的分类学处理。

关键词: 花药, 胚珠, 胚囊, 砂引草, 天芥菜属

Abstract:

The systematic position of Messerschmidia L. has been problematic which was ever moved into Tournefortia L. or Heliotropium L. Sporogenesis and gametogenesis in Messerschmidia sibirica were observed using conventional paraffin sectioning and light microscopy to provide embryological data for a better understanding of the systematic position of Messerschmidia. The results were as follows: (1)The anther was tetra-sporangiate, the primarily matured anther wall comprised four layers: the epidermis, endothecium, a middle layer and tapetum, the development of the anther wall was of the Dicotyledonous type, the tapetum with two-nucleate cells was secretary, the epidermis was persistent and the endothecium was irregularly 2- layered with fibrous thickening; (2)Microsporocyte undergone a meiotic division with a simultaneous cytokinesis resulting in a tetrahedral microspore tetrad, the mature pollen grains were 2-celled; (3)The ovule was unitegmic, anatropous and crassinucellate with a long thin micropyle and weak integument tapetum, some of the nucellar tissue was persistent at the stage of mature embryo sac; (4)The development of the embryo sac was of a Polygonum type, the shape of the mature embryo sac was fusiform with polar nuclei fused before fertilization and antipodal cells already degenerated. The embryological characters of Messerschmidia sibirica might be very similar to those of Heliotropium. Considering the stability of embryological characters within genus, the results suggested that it might be suitable to classify Messerschmidia into Heliotropium based on the molecular phylogenies.

Key words: Anther, ovule, Embryo sac, Messerschmidia sibirica, Heliotropium

中图分类号: