Shi Yinlian, Zhao Sha, Yao Jialing
College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
J Integr Plant Biol. 2009 Aug;51(8):774-81. doi: 10.1111/j.1744-7909.2009.00849.x.
Photoperiod-sensitive genic male-sterile (PSGMS) rice (Oryza sativa L.), a natural mutant found in the rice cultivar Nongken 58, is very useful for the development of hybrid rice cultivars. Despite its widespread use in breeding programs, the initial stage of the abortive development of PSGMS rice and the possible cytological mechanisms of pollen abortion have not been determined. In the present study, a systematic cytological comparison of the anther development of PSGMS rice with its normal fertile counterpart is conducted. The results show that pollen abortion in PSGMS rice first occurs before the pollen mother cell (PMC) stage, and continues during the entire process of pollen development until pollen degradation. The abortive process was closely associated with the abnormal behavior of the tapetum. Although tapetum degeneration in PSGMS rice initiates already at the PMC stage, it proceeds slowly and does not complete until the breakdown of the pollen. Such cytological observations were supported by the results of the TUNEL (TdT-mediated dUTP Nick End Labeling) assay, which detects DNA fragmentation resulting from programmed cell death (PCD), indicating that the premature tapetum degeneration is in the process of PCD.
光周期敏感型雄性不育（PSGMS）水稻（Oryza sativa L.）是在农垦58水稻品种中发现的一种自然突变体，对杂交水稻品种的培育非常有用。尽管其在育种计划中广泛应用，但PSGMS水稻败育发育的初始阶段以及花粉败育可能的细胞学机制尚未确定。在本研究中，对PSGMS水稻及其正常可育对照的花药发育进行了系统的细胞学比较。结果表明，PSGMS水稻的花粉败育首先发生在花粉母细胞（PMC）阶段之前，并在花粉发育的整个过程中持续，直至花粉降解。败育过程与绒毡层的异常行为密切相关。虽然PSGMS水稻的绒毡层退化在PMC阶段就已开始，但进展缓慢，直到花粉解体才完成。TUNEL（TdT介导的dUTP缺口末端标记）检测结果支持了这些细胞学观察结果，该检测可检测由程序性细胞死亡（PCD）导致的DNA片段化，表明过早的绒毡层退化正处于PCD过程中。
