GW3-1和IND109标记对普通小麦粒重的QTL定位分析

摘要

应用一个由115个系组成的W7984/ Opata85的重组自交系(RIL)群体,建立了一个由394个(292个RFLP、94个SSR和8个特殊的基因杂交探针)DNA分子标记组成的遗传连锁图,对小麦千粒重进行了单个标记的回归分析和复合区间作图的QTL定位,在单个标记的回归分析中检测到11个千粒重的QTLs(P<0.01);复合区间作图分析结果表明,其中4个标记bcd348a、GW3-1、IND109和Rz2的遗传效应较大,其贡献率分别为9.1%、19.0%、8.07%和8.14%,分别位于小麦的2BS、4AL、5BL和7DS上,特别是在水稻第3条染色体上控制籽粒大小的GW3-1和IND109分别位于小麦4A和5B染色体的长臂端.研究结果对小麦应用分子标记辅助选择或分子克隆基因有重要的参考价值.%Quantitative trait loci (QTL) analysis for thousand-kernel weight (TKW) was conducted using a set of 115 recombinant inbred lines (RILs) derived from a cross between the synthetic hexaploid wheat W7984 and the spring wheat cultivar Opata 85.Synthetic W7984 has larger kernels,especially in length,compared to Opata 85.Genotyping used 394 (292 RFLP,94 SSRs and 8 gene-specific hybridization probes) polymorphic markers.Eleven markers were linked to QTL corresponding to single marker regression analysis(P<0.01).Based on composite interval mapping(LOD>3.2),four intervals with contributions of 9.1%,19.0%,8.07%,8.14% were found to be linked to high thousand kernel weight on chromosomes 2BS,4AL,5BL and 7DS.The two markers adjacent to the rice gene mapped to the QTL intervals on chromosomes 4AL and 5BL.Some of the markers identified in this study may prove useful for marker-assisted selection in TKW and facilitate molecular cloning of this gene for wheat seed size.