荔枝雌花发育过程中花药败育的超微结构观察

应用扫描电镜、透射电镜和DAPI荧光染色方法对荔枝雌花发育过程中花药败育进行了研究,结果发现:败育的花药在减数分裂之前其药壁细胞即开始解体,减数分裂后,药壁组织发生细胞程序性死亡,导致对营养物质竞争力的减弱;发生凋亡的细胞,细胞核染色质固缩,其电子密度高于正常,核仁消失,染色质趋边化的双层核膜降解,有的核变形而凹陷,核膜破裂,在核膜破裂处可见到由核物质组成的凋亡小体.正在凋亡的细胞中,几乎都可观察到细胞核周围有许多线粒体,一些线粒体变形拉长,嵴肿胀,有的线粒体发生缢缩,线粒体膜降解而变得模糊,有的已破裂.表明线粒体与细胞凋亡可能有直接的关系.

Observation on Ultrastructure of Anther Abortion in the Process of Litchi (Litchi chinensis Sonn.)Femal Flower Development

Anther abortion during litchi female flower development were studied by applying scanning electric microscope,transmission electron microscope and DAPI fluorochrome methods.The results are as follows: the epidermic cells in the abortive anthers begin to deteriorate before meiosis,after meiosis programmed cell death(PCD) takes place in the anther wall which leads to weakened competition ability for nutriment.In the apoptosis cells,nuclear chromatin condenses and the electron density is higher than normal cells.Nucleolus disappear,the chromatin trends to the verge of nuclear membrane and double nuclear membrane degrades.Some nucleus deform and dish,the nuclear membrane breaks and apoptotic body made of nuclear substance can be seen around the place where nuclear membrane cracks.Many mitochondria can be observed around the nucleus in most of apoptosis cells.Some mitochondria deform and prolong,cristae swell,some constrict and its membrane degrade and become vague,others have ruptured already.The above showed that mitochondria may relate to cell apoptosis directly.