水稻光温敏核雄性不育系培矮64S花粉败育的细胞学机理(英文)

Cytological Mechanism of Pollen Abortion in Photoperiod Temperature Sensitive Genic Male Sterile Line Peiai 64S in Rice (Oryza sativa L.)

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.