银杏小孢子和花粉发育过程的超微结构观察  

Ultrastructural observation of the microsporogenesis and pollen development in Ginkgo biloba L.

作　　者：陆彦[1] 王頔[1] 张敏[1] 蒋小雪[1] 陈鹏[1] 王莉[1,2] 

机构地区：[1]扬州大学园艺与植物保护学院,江苏扬州225001 [2]中国科学院植物研究所,北京100093

出　　处：《电子显微学报》2011年第3期265-273,共9页Journal of Chinese Electron Microscopy Society

基　　金：江苏省研究生培养创新工程项目(苏教研[2009]10号);扬州大学高层次人才科研启动基金项目(2008-31)

摘　　要：利用透射电子显微镜技术对银杏(Ginkgo biloba L.)小孢子发生与花粉发育过程进行超微结构观察。结果表明:(1)在小孢子母细胞减数分裂期间,细胞内发生了"细胞质改组",主要表现在核糖体数量在历经不同发育时期逐渐减少,质体和线粒体形状与结构发生了规律性变化。第一次减数分裂完成后,两子核间无胼胝质壁沉积,而是被内质网和小泡所分隔,四分体呈四面体型,被胼胝质壁包围,胞质分裂属于同时型;(2)花粉发育的整个过程中,细胞内均含有丰富的线粒体、质体、高尔基体和内质网等细胞器。成熟花粉的四个细胞之间被各自独立的细胞壁分隔,壁上不具有胞间连丝,生殖细胞和管细胞内含有丰富的线粒体和质体,其遗传方式均有双亲遗传或单亲父系遗传的潜能;(3)花粉壁沉积始于减数分裂I早期,最早表现在小孢子母细胞质膜上沉积了少量的壁物质,减数分裂I末期形成初生花粉壁,游离小孢子后期,花粉外壁基本发育完成,有丝分裂开始后,花粉内壁发育形成。花粉壁的各层除外壁的覆盖层由绒毡层分泌外,其它均由小孢子自身发育而成。The ultrastructure of microsporogenesis and pollen development in Ginkgo biloba L.were investigated by transmission electron microscopy（TEM） in detail.Our results indicate that：（1） Cytoplasmic reorganization occurred during meiosis of microsporocytes and resulted in decreased ribosomes and regular changes of plastids and mitochondria.After the first meiosis,some organelle such as endoplasmic reticulum and vesicle were observed between two nuclei but no callosic wall.The tetrahedral tetrad wrapped by callose is of simultaneous type;（2） Rich cellular organs such as mitochondria,plastids,golgi and endoplasmic reticulum were present in the cells within the whole process of pollen development.The cell of mature pollen separates by respective cell wall,which shows no plasmodesmata.Many mitochondria and plastids existed in the generative cell and tube cell which show the potency of amphilepsis or single paternal inheritance;（3） At the early of meiosis I,some deposits of wall were observed on the plasma membrane of microsporocyte.Up to the late of meiosis I,pre-exine began to develop.Then,the exine rapidly developed,and was essentially completed by late microspore stage.And the intine formed at the beginning of mitosis.The microspore formed all layers of pollen wall except tectum of exine,which was secreted by tapetum.

关 键 词：银杏 小孢子 花粉 超微结构 

分 类 号：S792.95[农业科学—林木遗传育种]