小麦茎基腐病抗性QTL的分析

Analysis of QTLs for the Resistance to Crown Root in Wheat

为挖掘更多的茎基腐病抗性QTL用于分子标记辅助育种,以中抗茎基腐病品种CI12633和感茎基腐病品种扬麦158的重组自交系群体为材料,采用SSR和SNP等分子标记对群体中的94个家系进行基因型分析,绘制遗传连锁图,并结合3次室内群体的茎基腐病抗性鉴定结果对小麦茎基腐病抗性QTL进行定位。结果表明,与小麦茎基腐病抗性相关的QTL分布在1D、2B、3B(2)、7A和7D染色体上,可解释9.2%~14.6%的表型变异;1D和3B染色体上的抗性QTL来自CI12633,2B、7A和7D染色体上的抗性QTL来自扬麦158;1D、2B和3B(与Chr3B479785994紧密连锁)染色体上的抗性QTL为茎基腐病抗性主效QTL。发现的QTL及其紧密连锁的分子标记可为今后开展抗茎基腐病小麦分子标记辅助育种提供帮助。

In order to explore more QTLs resistant to wheat crown root(WCR) for molecular marker-assisted breeding, a medium resistant variety CI12633 and a susceptible variety Yangmai 158 were used to develop the recombinant inbred lines(RILs) population. SSR and SNP markers were generated to construct the genetic linkage map of the 94 RILs. Based on the linkage map and the evaluation data of WCR resistance of the RILs in three laboratory experiments, the QTLs resistant to WCR were mapped on the chromosomes of wheat. The result showed that 6 QTLs were detected on 1 D,2 B,3 B(2),7 A and 7 D chromosomes of wheat, which individually explains the phenotypic effect from 9.2% to 14.6%. Among them, the QTLs on 1 D and 3 B chromosomes were from CI12633,and those on 2 B,7 A and 7 D chromosomes were derived from Yangmai 158. QTLs on chromosomes 1 D,2 B and 3 B(tightly linked molecular marker Chr3 B479785994) with stable resistance to WCR were the major QTLs. The QTLs developed in this research and the tightly linked molecular markers will be beneficial to marker-assisted breeding for WCR resistance of wheat in the future.