植物研究2024，Vol.44Issue(1)：27-33,7.DOI:10.7525/j.issn.1673-5102.2024.01.005
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
Sporogenesis and Gametogenesis of Messerschmidia sibirica L.(Boraginaceae)and Their Taxonomic Implications
摘要
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.关键词
花药/胚珠/胚囊/砂引草/天芥菜属Key words
Anther/ovule/Embryo sac/Messerschmidia sibirica/Heliotropium分类
农业科技引用本文复制引用
孙豪愽,孔冬瑞,胡德昌..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[J].植物研究,2024,44(1):27-33,7.基金项目
鲁东大学博士启动基金(LY2015014) （LY2015014）
山东省省委省政府重点项目(鲁财预指[2021]1号) （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). （重大科技创新工程）
