鹅毛竹花药发育的超微结构观察

以鹅毛竹为材料,采用透射电子显微镜技术对花药发育的超微结构进行了系统研究。结果表明:鹅毛竹花药具4个药室,花药壁由表皮、药室内壁、中层和绒毡层组成。花药壁发育为单子叶型。造孢时期的造孢细胞胞质较浓厚, 线粒体、高尔基体丰富,含有大量的小泡,有少量油滴; 小孢子母细胞分裂期超微结构特征明显,分裂前期小孢子母细胞内含大量小泡、环状片层、高尔基体及线粒体,分裂期的小孢子母细胞胞质中的小泡、线粒体更加丰富,高电子致密颗粒的数量明显增加; 二分体细胞内具有丰富的线粒体,个别细胞壁上有胞质通道,胼胝质壁加厚; 刚释放出的小孢子壁薄,线粒体、环状片层丰富; 中央期小孢子形成期呈圆球形,细胞质稠密,具有丰富的线粒体、内质网、高尔基体等细胞器。随着小孢子的发育,其外壁逐渐增厚,在质膜外侧形成了3条宽窄不等的电子致密带,即外壁表层、基粒棒层和外壁内层,此时形成萌发孔; 成熟花粉粒充满淀粉粒。在花药发育期间出现雄性败育现象,主要表现为绒毡层细胞过早解体和小孢子母细胞及单核小孢子形态畸形,这些异常是雄性败育的主要原因之一。

The ultrastructure of anther development in Shibataea chinensis Nakai (Bambusoideae)

Shibataea chinensis belongs to the Bambusoideae, a large plant family with more than 1 000 bamboo species. Lacking of normal pollen development is one of the bottlenecks of bamboo molecular breeding. In order to provide additional data on this blossomed bamboo family, the ultrastructure of anther of S. chinensis was investigated with the methods of TEM in this study. The results are as follows: The anther wall consists of four layers. They are epidermis, endothecium, middle layer and tapetum. The development of anther wall belongs to the monocotyledonous type. The secondary sporogenous cells have some vesicles, annulate lamella, Golgi bodies and mitochondria. There are a plenty of vesicles, mitochondria and black high electron-dense cytoplasm in microspore mother cells. Dyad produces after the first meiosis, there are cytoplasmic channels on the cell wall with the thick callus. Pollen mother cells undergo the second meiosis to give rise to tetrad. Three electron-dense bands(the outer wall surface, the grana layer and the endexine)develops outside the pollen cell membrane during later central nucleus microspore,and the pollen germination aperture also develops at this time. When the pollens mature, many white plasmids and starch grains are in them. Male sterility phenomenon occurs during the process of anther development, such as the phenomena that the tapetum disintegrated earlier, the pollen mother cells and microspores are abnormal. So the abnormality of pollen is associated with the abortion of microsporocyte and microspore.