【作者】 徐青；

【导师】 田惠桥；

【作者基本信息】 厦门大学 ， 发育生物学， 2006， 硕士

【摘要】 应用电镜和细胞化学技术,分别对宁夏枸杞(Lycium barbarurn L.)花药发育及营养物质积累特点,做了超微结构研究和组织化学分析。主要实验结果如下:1.细胞质等变化特点枸杞小孢子发生和雄配子体发育过程中,主要细胞器发生了2次”细胞质改组”现象。第一次在小孢子母细胞减数分裂的前期Ⅰ--末期Ⅱ,核糖体数量减少,线粒体结构简化,到末期Ⅱ以后,核糖体数量增加,线粒体结构逐渐恢复;第二次在小孢子液泡化以后,核糖体和线粒体数量减少,质体肿胀,到二胞花粉早期,这些细胞器再度渐渐恢复正常。这些现象表明,在枸杞小孢子的发生、发育过程中都存在着“细胞质改组”现象,并且两次“细胞质改组”幅度有所不同。减数分裂过程中的“细胞质改组”是孢子体向孢子转变过程中,清除一些孢子体信息物质的过程;而小孢子发育过程中的“细胞质改组”则是孢子向配子体转变过程中清除孢子信息物质,是为雄配子体的分化做准备的过程。2.液泡的变化从小孢子母细胞至花粉粒成熟的过程中,液泡经历了3次明显的消长。第一次是在小孢子母细胞形成胼胝质壁的过程中,液泡贴着母细胞的细胞壁形成了一层液泡环,它的功能可能是消化原来的纤维素细胞壁;第二次是在小孢子母细胞减数分裂前,小孢子母细胞胼胝质壁内形成了体积较大的液泡环,它可能是将细胞质压缩到很小的程度以达到一定的核质比,启动减数分裂开始;第三次是在小孢子发育后期形成了一个大液泡,使小孢子具有了明显的极性。这既增加了小孢子的核质比,以启动小孢子进行第一次分裂,也造成了未来的不对称分裂,对两个细胞的命运有着重要的作用。小孢子发生和发育过程中液泡参与调控的现象以前很少有报道。3.花粉壁发育枸杞花粉原外壁原基在四分体中出现,四分体末期分化出了花粉原外壁。花粉外壁的内层在小孢子液泡化早期形成,而花粉内壁是在二胞花粉时期形成。最后,外壁覆盖层沉积了绒毡层细胞的降解物而形成了花粉覆盖物。花粉壁结构形成的时、空特征也反映出不同的花粉壁结构合成的机理差异。枸杞花粉原外壁的更多还原

【Abstract】 The ultrustructural featers of anther of Lycium barbarurn L. was studied using transmission electron microscope technique during microsporogenesis and the development of male gametophyte. The characteristic of distribution of nutriment during the development of anther was also studied using cytochemistry technique. The results as following:1. The characteristic of cytoplasm changeDuring the microsporogenesis and the development of male gametophyte some organelles displaied quantitative and structural change which means cytoplasm taking place“cytoplasmic reorganization”: from the prophase I to the telophaseⅡof meiosis, ribosomes decreased in number and the structure of mitochondria became reduced. It shows that the cytoplasm has happened dedifferentiation. After the meiosis the number of ribosomes increased and the inner structure of mitochondria became complex, suggestting a redifferentiation process of cytoplasm. At the vacuolation stage of the microspore, ribosomes and mitochondria of microspore toke place decreased in number again, and plastids became swell in shape reflacting a dedifferentiation process of microspore, and then resumed again at the early of bicellular pollens suggesting a redifferentiate process. It means that there were the“cytoplasm reorganization”phenomena in both the microsporogenesis and the development of male gametophyte, but the purpose of both“cytoplasm reorganizations”between the microsporegenesis and the development of microspore was different. Tthe former“cytoplasm reorganization”was to eliminate the sporophytic communicating material preparing microspore development, and the later“cytoplasm reorganization”was to eliminate the microspore’s communicating material preparing male gametophytic development.更多还原