Genetic analysis and gene mapping of a floral organ number mutant in rice （oryza sativa l.） | 一个水稻花器官数目突变体的遗传分析与基因定位

中国人. 摘　　要：水稻颖花突变体是开展鉴定和克隆水稻花器官发育基因研究的重要材料,在水稻重组自交系构建过程中,发现一个水稻花器官数目突变体,暂命名为fon6（floral organ number）。首先对突变体的花器官性状进行鉴定,然后利用F2群体进行遗传分析和基因定位。该突变体的特征为浆片颖壳化,内外稃和雌蕊增多,雄蕊减少并外露,雌雄配子均可育,但在自然条件下不能正常结实。突变体与正常品种杂交,F1代个体的表型与正常品种一致,F2群体表型分离比例符合3：1,说明该突变性状由一对隐性核基因控制。利用分布于水稻染色体上的分子标记,将突变位点定位在第3号染色体上的SSR标记RM14591与RM14464之间,遗传距离分别为0.24cM和10.5cM。

英语. The rice spikelet mutant is just the most important material for the identification and cloning of floral organ development genes in rice. A rice floral organ number mutant was found in development of a recombinant inbred lines （RIL） population, and temporarily named as fon6 （floral organ number）. The phenotypic traits of mutant floral organ were identified, and F2 segregation populations were used to precede genetic analysis and gene-mapping. The mutant was characterized with the phenotype of glumes-like lodicules, more glumes and pistils, and fewer stamens out of hull. Female and male gametes were fertile in the mutant, but no seeding in the natural condition. The F1 progeny crossed between mutant and normal varieties revealed a normal phenotype, and the segregation ratios showed a goodness of fit to 3：1 in F2 segregation populations. The result indicated that the mutant was controlled by a single recessive nuclear gene. Then molecular markers were developed and fon6 was located between SSR markers RM14591 and RM14464 on chromosome 3 with genetic distances of 0.24 cM and 10.5 cM, respectively.