Abstract: By using the methods of semi thin and thin section, the process of pollen development was comparatively studied in Peiai 64S, a photoperiod temperature sensitive genic male sterile line (PTGMS) and IR36, a fertile cultivar in rice. The development of Peiai 64S and IR36 did not differ up to microsporocyte formation stage; but since meiosis stage, male reproductive cells of Peiai 64S underwent several structural changes and ultimately terminated by early bicellular stage. These abnormal changes mainly occurred at two stages: (1) at meiotic prophase, almost half of Peiai 64S microsporocytes exhibited aberration, with sparse free ribosomes, underdeveloped mitochondria and many swollen endoplasmic reticula. These abnormal cells became dramatically vacuolated and hereafter disintegrated completely at later stage. (2) After the early uninucleate stage, nearly all of Peiai 64S microspores possessed malfunctional exine that was deviod of electron transparent region between sexine and nexine, and no intine was established. But, the development and disintegration of tapetum in Peiai 64S resembled those of IR36. The results proposed that the abnormalities of microsporocytic cytoplasm or pollen exine, rather than the tapetal development caused the pollen abortion of Peiai 64S.

Key words: rice, photoperiod temperature sensitive genic male sterile line (PTGMS), pollen, development, abortion, cytology

摘要： 采用半薄切片及薄切片技术, 对水稻光温敏核雄性不育系培矮64S 与正常水稻品种IR36 的花粉形成发育过程进行了比较研究。结果表明, 小孢子母细胞减数分裂之前, 培矮64S 与IR36 的发育过程基本相似。但从减数分裂开始, 培矮64S 的雄性性细胞出现一些异常变化, 并最终发育至二胞花粉早期败育。这些变化主要发生在两个阶段: (1) 减数分裂前期,约半数的小孢子母细胞的胞质出现异常, 游离核糖体稀少, 并具有不发育线粒体和大量泡状内质网。这类异常的小孢子母细胞在随后的发育中逐渐液泡化并最终解体。(2) 早期小孢子形成之后, 几乎所有小孢子外壁均发育异常, 表层与里层之间界限不清, 缺少中间透明带, 同时内壁没有形成。但是, 在花粉发育的整个过程中, 培矮64S 与IR36 绒毡层的发育和降解过程基本相似。据此认为, 培矮64S 的花粉败育可能是由小孢子母细胞或花粉外壁的异常发育造成的, 而不是由绒毡层发育引起的。

关键词: 水稻, 光温敏核雄性不育系, 花粉, 发育, 败育, 细胞学