Root system is important for belowground nutrients acquisition, and is also an important part to respond to drought stress. The purpose of this study was to dissect the genetic basis of seminal root architecture and coleoptile length of wheat by mapping quantitative trait loci (QTLs) of target traits. A doubled haploid (DH) population with 150 lines derived from a cross between two common Chinese wheat varieties Hanxuan 10 and Lumai 14 was used as the plant materials. Gel-chamber was employed to evaluate seminal root architecture traits, including maximum root length (MRL), root number (RN), total root length (TRL), root diameter (RD), root angle (RA), ratio of root dry weight to shoot dry weight (RDW/SDW), and coleoptile length (CL)of seedlings. QTLs for these traits were detected using mixed-model-based composite interval mapping method. A total of 12 additive-effect QTLs and 7 pairs of additive × additive QTLs associated with the target traits were mapped on chromosomes lA,lB, 2B, 2D, 3B, 4A, 4D, 5A, 5B, 6A, 7A, and 7B. The phenotypic variation explained by individual additive-effect QTL varied from 5.64％ to 12.37％. The additive effects ranged from 0.02 to 8.45. The phenotypic variation explained by each pair of epistatic QTLs varied from 8.70％ to 15.90％. The epistatic effects ranged from 0.20 to 7.45. Two QTL clusters for seedling root traits were detected on chromosomes 3B and 7A. These results would be helpful to maker-assisted selection of seminal root architecture and coleoptile.%为探讨小麦种子根结构及胚芽鞘长度的遗传基础,以小麦DH群体(旱选10号×鲁麦14)的150个株系为材料,利用凝胶室培养幼苗,测定种子根的数目和最大根长、胚芽鞘长度、根苗干重比等性状,并通过扫描仪测定幼苗种子根的总长度、根直径及角度.利用已经构建的DH群体遗传连锁图谱,采用基于混合线性模型的复合区间作图法分析上述性状的QTL.在1A、1B、2B、2D、3B、4A、4D、5A、5B、6A、7A和7B共12条染色体上检测到12个加性效应QTL和7对加性x加性互作效应QTL.QTL的加性效应值在0.02-8.45之间,对表型变异的贡献率为5.64%-12.37%.7对加性×加性互作效应QTL分布在1A-2B(2)、1A-6A、IB-2D、5B-6A、6A-7A和6A-7B等6对染色体之间,其互作效应值为0.20-7.45,对表型变异的贡献率为8.70%-15.90%.在染色体3B和7A上各检测到1个种子根结构相关性状的QTL簇.
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