Drought is a common abiotic stress factor that seriously affects wheat production in many parts of the world. To identify stable QTLs associated with three morphophysiological traits and four spectral reflectance indices (SRIs) in F6 (previous research) and F7 generations, recombinant inbred line (RIL) population from the cross between drought-sensitive (Yecora Rojo) and drought-tolerant (Pavon 76) cultivars was used in a study conducted under two irrigation regimes at the King Saud University Agricultural, Research Station. The parents and RILs were genotyped using a set of microsatellite loci. The composite interval mapping (CIM) analysis detected 53 QTLs for the three morphophysiological traits and four SRIs. The phenotypic variance (PV) explained varied from 3 to 44%. Twelve co-located QTLs were identified on chromosomes: 1B, 1D, 2A, 2D, 3A, 3B, 4B, 5B and 5D. The highest number of co-located QTLs was identified on chromosomes 5B. The QTL on chromosome 5B flanked by barc109–barc59 showed significant effects for the morphophysiological traits and SRIs under the two irrigation regimes. This QTL explained the highest proportion of PV (14.0–44.0%) with LOD score (3.2–13.2). Seven stable QTLs were identified in both F6 and F7 generations. Of these QTLs, QWc.li-5B co-localized with QNdvi.li-5B and flanked by markers Barc109 and Barc59 was identified in F6 and F7 generations under reduced irrigation. QWc.li-5B explained the highest PV (43 and 44%) for relative water content in F6 and F7 RIL, respectively. The novel and consistent QTLs obtained can be used in marker-assisted selection to improve drought tolerance in wheat.

干旱是一种常见的非生物胁迫因素，会严重影响世界许多地方的小麦产量。为了在F6（先前的研究）和F7世代中鉴定与三个形态生理特征和四个光谱反射指数（SRI）相关的稳定QTL，使用干旱敏感（Yecora Rojo）和耐旱（Yecora Rojo）杂交的重组自交系（RIL）种群（ Pavon 76）品种在沙特国王大学农业研究站的两种灌溉制度下进行了研究。使用一组微卫星基因座对亲本和RIL进行基因分型。复合间隔图（CIM）分析检测到53个QTL，用于三个形态生理特征和四个SRI。表型差异（PV）的解释范围为3％至44％。在染色体上鉴定出了十二个共居QTL：1B，1D，2A，2D，3A，3B，4B，5B和5D。在染色体5B上鉴定到最多的同位QTL。barc109–barc59两侧的5B染色体上的QTL对两种灌溉制度下的形态生理特征和SRI具有显着影响。该QTL解释了最高的PV（14.0–44.0％）和LOD评分（3.2–13.2）。在F6和F7代中鉴定出七个稳定的QTL。在这些QTL中，QWc.li-5B共定位与QNdvi.li-5B和侧翼以标记Barc109和Barc5 9在F6，并在减压灌溉F7世代被确定。QWc.li-5B分别解释了F6和F7 RIL中相对水含量的最高PV（分别为43％和44％）。获得的新颖且一致的QTL可用于标记辅助选择以提高小麦的耐旱性。