在水稻转基因后代中,筛选到1个与雌配子育性相关的突变体,该突变体自交后代群体外源标记基因(潮霉素磷酸转移酶hpt)保持1∶1的分离规律,连续6代自交没有得到纯合株系；正、反杂交以及测交分析显示,潮霉素抗性基因只能通过雄配子进行传递；结实率统计分析表明具有外源标记基因hpt的单株有近乎一半的雌配子发生败育,胚囊的育性与外源基因hpt共分离；Southern-blot分析表明该突变体T-DNA是以单拷贝方式整合到水稻染色体上.这些分析表明该突变体是1个T-DNA插入导致的雌配子体不育突变体(暂定名为female gametogenesis sterile 1,fgs1).细胞学观察显示,突变体fgs1花粉育性与野生型明恢86近似,但是其雌配子发育受阻,突变基因型雌配子体在8核胚囊时期,卵细胞、助细胞、反足细胞团以及中央极核依次解体退化,无法完成授粉受精.%We isolated a female gamete to a fertility-related mutant, from a T-DNA insertional population of indica rice. The transgenic plants carrying a T-DNA insertion displayed phenomena that hygromycin resistance and sensitivity segregation ratios showed 1 ∶1 by x2-test and the homozygous progeny was not found in 6 successive generations. Reciprocal crosses between heterozygous plants and the wild types showed that the allele could not be transmitted through the female. Statistical analysis showed that the ripening rate of exogenous marker gene hpt with the plant has occurred almost half of the female gamete abortion, embryo sac fertility and closely linked to the hpt gene. Southern-blot showed that the mutant carried with a copy of T-DNA insertion. All of these indicated that the mutant is a gametophyte ovary sterile mutant caused by T-DNA insertion (tentatively named as female gametogenesis sterile 1, fgsl). Cytologic observation showed that pollen fertility of fgsl was as normal as the wild type minghui 86, but the development of female gamete was blocked. In the female gamete of fgsl mutant, we found that egg cell (E), synergids (S), antipodal cells (A) and polar nuclei (P) appeared disaggregation one by one during the 8 nucleuses period and the fertilization halted.
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