大豆遗传图谱的构建和若干农艺性状的QTL定位分析

大豆许多重要农艺性状都是由微效多基因控制的数量性状,对这些数量性状进行QTL定位是大豆数量性状遗传研究领域的一个重要内容.本研究利用栽培大豆科新3号为父本、中黄20为母本杂交得到含192个单株的F2分离群体,构建了含122 个SSR标记、覆盖1719.6cM、由33个连锁群组成的连锁遗传图谱.利用复合区间作图法,对该群体的株高、主茎节数、单株粒重和蛋白质含量等农艺性状的调查数据进行QTL分析,共找到两个株高QTL,贡献率分别为9.15%和6.08%;两个主茎节数QTL,贡献率分别为10. 1%和8.6%;一个蛋白质含量QTL,贡献率为9.8%;一个单株粒重QTL,贡献率为11.4% .通过遗传作图共找到与所定位的4个农艺性状QTL连锁的6个SSR标记,这些标记可以应用于大豆种质资源的分子标记辅助选择,从而为大豆分子标记辅助育种提供理论依据.

Construction of Genetic Map and QTL Analysis for Some Agronomic Traits in Soybean

Many important agronomic traits of soybean are quantitative traits, which are controlled by polygenes. Tagging QTL for these quantitative traits is a very important field in soybean quantitative genetics research. Kexin 3 and Zhonghuang 20 are releasing cultivars in Huanghuaixia ecological district with excellent quality traits. A cross of Kexin 3 and Zhonghuang 20 was made, then selfed to construct F 2 population which has 192 plants. A genetic linkage group of soybean genome was constructed, which consisted 33 linkage groups with 122 SSR markers covering 1719 6 cM. The composite interval mapping was used to identify quantitative trait loci (QTL) associated with plant height, nod number of main stem and protein content. Two QTL were found for plant height with the phenotypic variance explained of 9 15% and 6 08% respectively; two for nods number of main stem with the phenofypic variance explained of 10 1% and 8 6% respectively; one for protein content with the phenotypic variance explained of 9 8%. Six markers linked to the QTL for four agronomic traits were found and can be used in molecular marker assisted selection in soybean.