Abstract: Under natural conditions with long day and high temperature or short day and low temperature,the plant morphology,including leaf collar,ear length and days to heading,and the morphological changes of cells during fertility abortion were observed on the rice,SE21S.The relationship between the plant characteristics and microspore development was established.The results showed that(1) light and temperature were the significant climatic factors affecting the fertility when plant morphological characteristics were-1.0-4.5cm long on leaf collar,12.5-14.6cm long on young panicles,6.4-9.6 days before heading and in the single nucleus stage of the microspore development;and(2) the sterile pollen microspores appeared shrunk and irregular,while the fertile microspores smooth and regular.But during the stage from motrecyte to tetracyte,there was no significant difference in their cellular morphology observed in comparison with the normal rice(control).