应用石蜡切片技术和脱氧核糖核苷酸转移酶介导的缺口末端标记法(TUNEL),对光敏核不育水稻农垦58S和可育水稻农垦58N的花粉及花药壁发育过程进行了研究。结果表明:农垦58S雄性败育起始于花粉母细胞形成期,在发育过程中持续进行,终结于单核晚期,形成典败型花粉;TUNEL检测显示,农垦58S的绒毡层细胞在花粉母细胞时期启动细胞程序性死亡(PCD),但解体过程缓慢,一直持续到花粉发育后期,使单核花粉无法获得所需的营养物质而败育。
A systematic cytological comparison of the anther development of the PSGMS rice with its normal fertility counterpart was conducted. The results showed that pollen abortion in the PSC-MS rice occurred first no later than the pollen mother cell (PMC) stage and continued during the entire process of pollen development till pollen degradation. This abortive process was closely associated with the abnormal behavior of the tapetum. Although tapetum degeneration in the PSGMS rice initiated as early as at the PMC stage, it proceeded slowly and did not complete until the breakdown of the pollen, in sharp contrast to the rapid disintegration of the tapetal layer during late microspore to bicellular pollen stage in the fertile rice. Such cytological observation was supported by the results of the TUNEL (TdT- mediated dUTP Nick End Labeling) assay that detects DNA fragmentation resulting from programmed cell death (PCD),indicating that the tapetum degeneration Occurs in the process of PCD.