Flag leaf senescence is a critical factor affecting the yield and quality of wheat. The aim of this study was to identify QTLs associated with flag leaf senescence in an F₁₀ recombinant inbred line population derived from durum wheats UC1113 and Kofa. Bulked segregant analysis using the wheat 660K SNP array identified 3225 SNPs between extreme-phenotype bulks, and the differential SNPs were mainly clustered on chromosomes 1A, 1B, 3B, 5A, 5B, and 7A. BSR-Seq indicated that the significant SNPs were mainly located in two intervals of 354.0–389.0 Mb and 8.0–15.0 Mb on 1B and 3B, respectively. Based on the distribution of significant SNPs on chromosomes 1B and 3B, a total of 109 insertion/deletion (InDel) markers were developed, and 8 of them were finally used to map QTL in UC1113/Kofa population for flag leaf senescence. Inclusive composite interval mapping identified two major QTL in marker intervals Mar2005–Mar2116 and Mar207–Mar289, explaining 14.2–15.4% and 31.4–68.6% of the phenotypic variances across environments, respectively. Using BSR-Seq, gene expression and sequence analysis, the TraesCS1B02G211600 and TraesCS3B02G023000 were identified as candidate senescence-associated genes. This study has potential to be used in cloning key genes for flag leaf senescence and provides available molecular markers for genotyping and marker-assisted selection breeding.

旗叶衰老是影响小麦产量和品质的关键因素。本研究的目的是鉴定源自硬粒小麦 UC1113 和 Kofa 的 F ₁₀重组自交系群体中与旗叶衰老相关的 QTL。使用小麦660K SNP阵列进行批量分离分析，鉴定出极端表型批量之间的3225个SNP，差异SNP主要聚集在染色体1A、1B、3B、5A、5B和7A上。BSR-Seq表明显着的SNP主要位于1B和3B上的354.0-389.0 Mb和8.0-15.0 Mb两个区间。根据1B和3B染色体上显着SNP的分布，总共开发了109个插入/缺失（InDel）标记，其中8个最终用于定位UC1113/Kofa群体旗叶衰老的QTL。包含性复合区间作图在标记区间 Mar2005-Mar2116 和 Mar207-Mar289 中确定了两个主要 QTL，分别解释了不同环境中 14.2-15.4% 和 31.4-68.6% 的表型差异。使用 BSR-Seq、基因表达和序列分析，TraesCS1B02G211600 和 TraesCS3B02G023000 被鉴定为候选衰老相关基因。该研究有望用于旗叶衰老关键基因的克隆，并为基因分型和标记辅助选择育种提供可用的分子标记。