山农01-35×藁城9411重组自交系遗传图谱构建及粒重QTL分析

Construction of Genetic Map and Analysis of QTLs for Grain Weight Using a RIL Population Derived from Shannong 01-35 × Gaocheng 9411

为利用分子遗传图谱进行小麦产量数量性状位点定位分析,以大粒高产小麦品系山农01-35和强筋小麦藁城9411为亲本,衍生了含182个家系的重组自交系(RIL)F8群体,用442个DArT标记、59个SSR标记和1个TaGW2-CAPS标记,构建了包括29个连锁群的分子遗传图谱,总遗传长度为4084.5cM,标记间平均距离为8.13cM。定位了54个新标记位点,包括44个DArT和10个SSR标记,分布于除4D、6B、7B外的其他18条染色体上。用该分子遗传图谱和4个环境粒重表型值,共检测到7个影响粒重的加性QTL,分别位于1B、4B、5B、6A染色体,其中QGW4B-7、QGW5B-20和QGW6A-29在单环境分别定位和4个环境共同定位2种方法中均能检测到。QGW4B-7、QGW5B-12和QGW6A-29对粒重的贡献率均超过10%,为主效QTL。本研究结果可为小麦高产优质性状的QTL分析及分子标记辅助选择提供参考。

The objectives of this study were to construct a new linkage map of wheat using a recombinant inbred line（RIL） population derived from the cross between Shannong 01-35 and Gaocheng 9411 and locate quantitative trait loci for thousand-grain weight（TGW） using this map.The RIL population,consisting of 182 lines,was obtained via single-seed descendent method until the F8 generation.The genetic map consisted of one TaGW2-CAPS,59 SSR,and 442 DArT markers in 29 linkage groups,including 54 novel markers（44 DArT markers and 10 SSRs） assigned into 18 linkage groups.The total genetic length of the map was 4084.5 cM with an average interval distance of 8.13 cM.The 182 RILs and their parents were grown in four environments from 2008 to 2010,and QTLs associated with TGW were identified using mixed linear model based on both separated and joint environments.A total of seven QTLs were detected including three QTLs（QGW4B-7,QGW5B-20,and QGW6A-29） commonly found using both methods.Three major QTLs,i.e.,QGW4B-7,QGW5B-12,and QGW6A-29,exhibited phenotypic contributions higher than 10%.These results suggest that the QTLs detected by using the successfully constructed genetic map are valuable in molecular marker-assisted selection in wheat.