水稻稀穗突变体的遗传分析及其基因的初步定位

Genetic Analysis and Gene Mapping of a Lax Panicle Mutant Oslp in Rice(Oryza Sativa L.)

水稻的穗形与其产量关系密切,也是研究的一大热点。利用60Co-γ射线辐射诱变水稻68902B,筛选到一个水稻稀穗突变体,暂命名为Oslp(Oryza sativa lax panicle)。研究了该突变体的主要农艺性状与稀穗的遗传方式,并对稀穗突变基因Oslp进行了分子定位。结果显示稀穗突变体Oslp的每穗粒数为104粒、二次枝梗数目为7个,它们都显著地少于原品种68902B每穗粒数的124粒和二次枝梗数目的 20个。遗传分析揭示突变体Oslp的稀穗性状受一对隐性核基因控制。将(籼稻品种261S×稀穗突变体Oslp)F2代中的稀穗个体作为定位群体,结合BSA和SSR分子标记技术,将基因Oslp定位在第7号染色体短臂的2个分子标记FR-3和FR-4之间,基因Oslp与FR-3和FR-4的遗传距离分别为0.6 c M和0.8 c M。

Panicle morphology is closely connected with rice yield, which is one of the hotspots in rice research.A lax-panicle mutant was selected from rice 68902 B by the radiation of60Coγ-ray, and named as Oslp(Oryza sativa lax panicle) temporarily. In this study, the main agronomic traits and inheritance of the mutant Oslp were performed, as well as the Oslp gene was mapped. The mutant Oslp had 104 grains per panicle and 7 secondary branches, which were significantly less than 124 grains per panicle and 20 secondary branches of 68902 B. Genetic analysis revealed that the mutant type was controlled by a single recessive nuclear gene. F2(indica rice 261S×the mutant Oslp) population was developed for Oslp gene mapping. Based on the combination of the SSR markers and BSA analysis, the Oslp gene was mapped on the short arm of chromosome 7 of rice and flanked by FR-3 and FR-4. The genetic distances of FR-3 and FR-4 to Oslp gene were 0.6 c M and 0.8 c M, respectively.