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应用电子显微镜技术对芝麻(Sesamum indicum L.)小孢子发育进行了研究。在减数分裂前,小孢子母细胞含有丰富的细胞器。核膜有很多核孔,且有较大的通道。各小孢子母细胞之间通道明显,有强烈的物质交换作用。小孢子母细胞减数分裂为同时型。四分体小孢子中质体位于一侧,高尔基体含量增加。有丝分裂形成的营养细胞与生殖细胞由胼胝质壁隔开。生殖细胞中无高尔基体,少量质体呈退化状态。游离后的生殖细胞由两层质膜包围,这两层质膜有时膨大成很宽的隔间。营养细胞中细胞器在数量和大小上显著增长,在质体中迅速积累淀粉。花粉粒成熟时为2-细胞花粉粒。在四分体时小孢子形成原外壁,游离后原外壁上沉积孢粉素,形成外壁外层,在萌发沟处无外壁外层。
Microspore development of Sesamum indicum L. was studied by electron microscopy. Before meiosis, microspore mother cells are rich in organelles. Nuclear membrane has many nuclear pores, and a larger channel. Pathways between the microspore mother cells obvious, there is a strong role of material exchange. Microspore mother cell meiosis into simultaneous. Tetraploid microspores in plastids located on one side, Golgi content increased. Mitosis of vegetative cells and germ cells separated by the callose wall. Germ cells without Golgi, a small amount of plastid was degraded. The free germ cells are surrounded by two layers of plasma membranes, which sometimes expand into very wide compartments. Organelles in vegetative cells significantly increase in number and size, rapidly accumulating starch in the plastids. Pollen grains mature when the 2-cell pollen grains. In the tetrad microsphere formed the original outer wall, the original outer wall after deposition of sporopollenin, forming the outer wall of the outer wall in the germination groove without outer layer.