We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spike...We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spikelets are absent and the terminal spikelet displays variegated structures in the mutant. An F2 population from the cross between the lax mutant and a japonica variety, W11, was constructed and analyzed. Using microsatellite and CAPS markers, the lax locus was mapped on the long arm of chromosome 1, co-segregated with a CAPS marker, LZ1, within an interval of 0.28 cM between a CAPS marker, HB2, and a microsatellite marker, MRG4389. RT-PCR analysis revealed that the expressions of the rice B-function MADS-box genes OsMADS2, OsMADS4, OsMADS16 and OsMADS3 were significantly reduced, whereas the expression of the rice A-function gene RAP1A was not altered.展开更多
基金This work was supported by the State High Technology Research and Development Project(Grant No.2001AA21108101).
文摘We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spikelets are absent and the terminal spikelet displays variegated structures in the mutant. An F2 population from the cross between the lax mutant and a japonica variety, W11, was constructed and analyzed. Using microsatellite and CAPS markers, the lax locus was mapped on the long arm of chromosome 1, co-segregated with a CAPS marker, LZ1, within an interval of 0.28 cM between a CAPS marker, HB2, and a microsatellite marker, MRG4389. RT-PCR analysis revealed that the expressions of the rice B-function MADS-box genes OsMADS2, OsMADS4, OsMADS16 and OsMADS3 were significantly reduced, whereas the expression of the rice A-function gene RAP1A was not altered.
文摘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。
