与相应的二倍体水稻相比，同源四倍体的生殖特性发生了明显的变化，有性生殖能力明显变弱。在其花药内正常花粉粒数比较少（１５．６９％～２９．９８％），而败育花粉粒数比较多，它们的自交结实率（１７．７１％～３１．９５％）明显下降。ＡＰＩＶ（４）正常胚囊（４３．０％）数少，而退化胚囊（３６．０％）和变异胚囊（２１．０％）数多。ＡＰＩＶ（４）的花粉管在其花柱中的伸入速度明显变慢，双受精频率下降而单受精频率增加，在其自然群体中存在着胚自发现象。同源四倍体水稻有性生殖的异常可能为无融合生殖基因的表达创造了条件。 Compared with the corresponding diploid rice, the autotetraploid reproductive characteristics of a significant change in sexual reproduction was significantly weakened. In the anthers, the number of normal pollen grains was less (15.69% -29.98%), while the number of aborted pollen grains was more, their selfed seed setting rate (17.71% ~ 31.95%) decreased significantly . The number of normal embryo sacs (43.0%) was lower in APIV (4) than in degenerated embryo sacs (36.0%) and mutated embryo sacs (21.0%). The pollen tube of APIV (4) penetrated into the style significantly slower, the frequency of double fertilization decreased and the frequency of single fertilization increased, spontaneous embryo existed in its natural population. Abnormalities in sexual reproduction of autotetraploid rice may create conditions for the expression of apomictic genes.