Cytological Characters Of The Rice Light And Temperature Sensitive Genic Male Sterile Line

By using techniques of fresh intact anther observation, fluorescence observation and investigation of paraffin section, an extensively cytological study was conducted on the pollen development of JIYUGENG ,a normal cultivar , and D18S, a photo-thermo sensitive genie male sterile line . On one hand , we respectively analyzed their change characteristics at every stage in the process of pollen formation. On the other hand, we summarized the cytological features and possible causes to lead to pollen abortion in D18S. The main results we obtained are shown as follow:1. Abnormality of microspore:At middle microspore stage , a serious of abnormal phenomenons began to appear in the microspore of D18S, including the shrink of cytoplasm, the disintegration of the container, the atresia of cytoplasm and nuclear, and the volume of microspore which only accouted for 2/3 as that of the normal pollen.2.Abnormality of tapetum :The tapetum in JIYUGENG began to break up at meiosis stage, and basically disintegrated at late microspore stage. In D18S, on the contrary, there is no apparent disintegration at meioses stage.,only in a few tapetum cells occurred some blank regions. At middle microspore stage, the tapetum agglemorated and looked concave and wavy in appearance . A thick band -shape structure existed at all the time of late microspore stage. Comparing to JIYUGENG, disintegration is postponed correspondingly at every stage in D18S.3.Stage of pollen abortion:With the fact that most of mature pollens are typical abortive pollens and the observation on the structure of microspore, we identified that the critical period for pollen abortion was from late microspore stage to early bicellular pollen stage , and many crucial changes occurred just at that period.