同源四倍体水稻雌雄配子体的多态性

同源四倍体水稻（2n＝4x＝48）由于其细胞内染色体数的倍增而导致生殖性状发生了明显变化．雄配子体中存在较少的正常花粉粒（13．35％～17．49％）和较多的败育花粉粒（82．51％～86．65％）．败育花粉粒包括典败、圆败和染败花粉粒．同源四倍体水稻APⅣ（4）的成熟胚囊内存在着正常蓼型（43．0％）、退化型（36．0％）和变异型（21．0％）胚囊．变异型胶囊中包括双卵卵器（71．4％）、三卵卵器（17．5％）和无助细胞（11．1％）胚囊．不同季节，APⅣ（4）颖花内的多卵频率存在着明显差异，同一季节强势颖花的多卵频率明显高于弱势颖花的多卵频率．由此认为，同源四倍体水稻的雌雄配子体表现出异常发育状态，有性生殖能力已明显变弱．

Polymorphism of male and female gametophytes in autotetraploidy rices

Due to the double chromosomes in the cell, the autotetraploidy rices showed obvious variance in reproductive characters. In the male gametophytes, there were less normal pollen grains (13.35 %-17.49%), but a lot of abortive ones (82.51%-86.65%), including 3 kinds of typical, spherical and stained abortions. The polygonum type (43.0%), the degenerated type (36.0%) and the varied type (21.0%) in the ripe sacs of autotetraploidy rice, APⅣ (4), were observed, which indicated the morphological variance of the female gametophytes.Three kinds of abnormal phenomena of double egg-apparatuses (71.4%), 3 egg-apparatuses (17.5%) and no synergids (11.1%) in the varied sacs were found. There were obvious differences in the poly-egg frequency in the caryopses of APⅣ(4) in different seasons. The poly-egg frequency of the strong caryopses was outstandingly higher than that of the weak catyopses. It was suggested that the female and male gametophtes of the autotetraploidy rices had abnormal morphotropy, and weaker sexually reproductive ability.