裸粒水稻小穗异常形态结构及败育分析

对经过１５ 年分蘖繁殖的裸粒水稻小穗及颖花的雌雄蕊发育观察发现，从小穗原基起即显示出多花形态性状，颖花中内外稃伸长不钩合。在小孢子发生过程中，许多细胞在减数分裂初期存在穿壁现象。这可能导致染色体数目变化，结构异常，减数分裂不正常，从而产生大小不等的小孢子。这些小孢子在二核或三核花粉时停止发育并解体成为无生活力花粉，导致裸粒水稻败育。此外，雌蕊结构也有多种异常

Study on the abnormal morphology and structures of spikelet and the abortive processes of pollen in naked-seed rice

The developmental process of spikelet and floret of naked seed rice was observed after having been tillering propagation for 15 years.It was found that the structure of spikelet was different from that of rice and was similar to that of wheat with 3 florets usually.The lemma and palea extended and bidivided.During micro sporogenesis,the chromosome migration between pollen mother cells appeared frequently at the early stage of meiosis.This could result in the variation of chromosome numbers and structures and abnormal behavior of meiosis.Subsequently unequal pollens were produced.The plasmolysis of microspores at the late mononuclear stage finally resulted in abortive pollens.There were also some abnormal structures in the pistil,e.g.ovary semifused,two ovules developed in one ovary,nucellus degenerated.