水稻籽粒长、宽快速增长期为花后 0～ 6天 ,粒型 (长 /宽 )形成期为花后 1 5天 ;抽穗后 0～ 3天粒重发育缓慢 ,之后迅速增长 ,至第 1 8天粒重发育基本完成 ;受季节影响 ,水稻晚季粒型值大于早季 ,尤其是籼稻品种其早、晚季粒型值的差异达极显著水平 ;淀粉粒在胚乳中形成的时间为子房受粉后 2～3天 ,并于边缘的胚乳细胞中最先出现 Grain length and breadth of rice increased from 0 to 6 days after anthesis, and the formation period of grain type (length and breadth) was 15 days after anthesis. Grain weight developed slowly from 0 to 3 days after heading, and then increased rapidly to 1 The development of grain weight at 8 days was basically completed. According to the seasons, the late grain type of rice was more than that of early season, especially the early and late grain types of indica rice. The time of formation of starch grains in endosperm was Ovary powder after 2 to 3 days, and in the marginal endosperm cells first appeared