Earlier studies have shown the significant impact of leaf glaucousness and cooler canopies on wheat (Triticum aestivum L.) yield. However, breeding for drought adaptive traits and potential yield as responses to heat or water deficit were poor. The genetic basis for drought-adaptive traits and yield potential were assessed using quantitative trait locus (QTL) analysis. The 180 recombinant inbred lines (RILs) were derived from a cross between ‘Len’ (USA) and ‘Halberd’ (Australian) wheat lines. The RIL population and the parents were genotyped with a 90K Infinium single nucleotide polymorphism (SNP) library to construct 22 linkage groups. The QTLs segregating for leaf epicuticular wax (EW), cooler canopies, drought susceptibility index (DSI), and grain attributes were identified in the population across five environments. The QTLs associated with leaf EW, cooler canopies, DSI–mean single head weight (MSHW), DSI–thousand-kernel weight (TKW), and grain attributes co-localized on chromosomes 1A, 2B, 3B, 6B, 7A, and 7B. Gene ontology of the leaf EW QTLs on chromosomes 2B and 3B indicated that their sequences were similar to an Arabidopsis ABC transporter gene, and the leaf EW QTL on chromosome 7B was similar to the sorghum [Sorghum bicolor (L.) Moench] ethylene-insensitive gene. The favorable alleles associated with moisture stress tolerance were associated with the Halberd parent. The genetic loci (QWax.tam-3B and QCTP.tam-2B, QDSIM.tam-2B.1) with higher logarithm of odds (LOD) and R² values could be important potential tools in breeding to improve. The chromosomal regions identified in this study can provide breeders with additional tools to develop drought- and heat-tolerant cultivars through breeding.

中文翻译：

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绘制小麦叶片表皮蜡质、冠层温度和干旱易感指数的遗传位点

较早的研究表明，叶白霜和较冷的冠层对小麦（Triticum aestivumL.) 产量。然而，干旱适应性状和潜在产量作为对热或缺水的反应的育种很差。使用数量性状基因座 (QTL) 分析评估干旱适应性性状和产量潜力的遗传基础。180 个重组自交系 (RIL) 来自“Len”（美国）和“Halberd”（澳大利亚）小麦品系之间的杂交。使用 90K Infinium 单核苷酸多态性 (SNP) 文库对 RIL 种群和亲本进行基因分型，以构建 22 个连锁群。在五种环境中的人群中鉴定出分离叶表皮蜡质 (EW)、较冷冠层、干旱易感性指数 (DSI) 和谷物属性的 QTL。与叶 EW、较冷冠层、DSI-平均单头重 (MSHW)、DSI-千粒重 (TKW) 相关的 QTL，和谷物属性共同定位在染色体 1A、2B、3B、6B、7A 和 7B 上。染色体 2B 和 3B 上叶 EW QTL 的基因本体表明它们的序列类似于拟南芥ABC 转运蛋白基因，7B 号染色体上的叶 EW QTL 与高粱 [ Sorghum bicolor (L.) Moench] 乙烯不敏感基因相似。与水分胁迫耐受性相关的有利等位基因与戟亲本相关。具有较高几率对数 (LOD) 和R ² 值的遗传位点（QWax.tam-3B 和 QCTP.tam-2B、QDSIM.tam-2B.1）可能是育种中重要的潜在改进工具。本研究中确定的染色体区域可以为育种者提供额外的工具，以通过育种开发耐旱和耐热的品种。