Abstract

Stripe rust, caused by Puccinia striiformis Westend. f.sp. tritici Erikss. (Pst), is one of the most devastating diseases of wheat (Triticum aestivum L.) globally. Exploring and utilizing new sources of resistance is essential for breeding resistant wheat cultivars. Thus, a doubled haploid population (n = 291) derived from the cross ‘AAC Innova’/‘AAC Proclaim’ was evaluated to dissect the genetics of resistance in the cultivar ‘AAC Innova’. This population was evaluated for stripe rust severity in disease nurseries at Creston, British Columbia (in 2016 and 2020), and Lethbridge, Alberta (in 2016, 2017 and 2020), and genotyped using the wheat 90 K SNP assay. A high-density genetic map was constructed which consisted of 7112 SNP markers with an average marker interval of 2.3 cM. Quantitative trait loci (QTL) mapping identified one major (QYr.lrdc-2A) and 10 minor effect (QYr.lrdc-2B.1, QYr.lrdc-2B.2, QYr.lrdc-2B.3, QYr.lrdc-2B.4, QYr.lrdc-2D, QYr.lrdc-3B, QYr.lrdc-5A, QYr.lrdc-5B, QYr.lrdc-5D and QYr.lrdc-7D) loci. The QTL QYr.lrdc-2A was consistently effective against Pst races across all environments and explained up to 33.0% of the phenotypic variation. Other QTLs were either less consistent or environment specific. ‘AAC Innova’ contributed stripe rust resistance alleles for most of the QTLs except for QYr.lrdc-2D, QYr.lrdc-5A and QYr.lrdc-7D. The QTLs identified in this study should be valuable for diversifying the sources of genetic resistance against current and new virulent races of Pst. In particular, the ‘AAC Innova’-derived QTL QYr.lrdc-2A could be a valuable source of resistance to incorporate into commercial cultivars and combine with other genes using the associated SNP markers identified in this study.

摘要

条锈病，由Puccinia striiformis Westend引起。f.sp. 小白兔埃里克斯。( Pst ), 是小麦 ( Triticum aestivum )最具破坏性的病害之一L.) 全球。探索和利用新的抗性来源对于培育抗性小麦品种至关重要。因此，评估了源自交叉“AAC Innova”/“AAC Proclaim”的双单倍体种群（n = 291），以剖析栽培品种“AAC Innova”的抗性遗传学。在不列颠哥伦比亚省克雷斯顿（2016 年和 2020 年）和艾伯塔省莱斯布里奇（2016 年、2017 年和 2020 年）的病害苗圃中评估了该种群的条锈病严重程度，并使用小麦 90 K SNP 检测进行基因分型。构建了由7112个SNP标记组成的高密度遗传图谱，平均标记间隔为2.3 cM。数量性状基因座 (QTL) 作图确定了 1 个主要 ( QYr.lrdc-2A ) 和 10 个次要效应 (QYr.lrdc-2B.1、QYr.lrdc-2B.2、QYr.lrdc-2B.3、QYr.lrdc-2B.4、QYr.lrdc-2D、QYr.lrdc-3B、QYr.lrdc-5A、 QYr.lrdc-5B、QYr.lrdc-5D和QYr.lrdc-7D ) 基因座。QTL QYr.lrdc-2A在所有环境中对Pst 小种始终有效，并解释了高达 33.0% 的表型变异。其他 QTL 要么不一致，要么环境特定。除了QYr.lrdc-2D、QYr.lrdc-5A 和 QYr.lrdc-7D之外，“AAC Innova”为大多数 QTL 贡献了条锈病抗性等位基因。本研究中鉴定的 QTL 应该对多样化针对Pst 的当前和新的毒力小种的遗传抗性来源很有价值。特别是，“AAC Innova”衍生的 QTL QYr.lrdc-2A 使用本研究中鉴定的相关 SNP 标记将其整合到商业栽培品种中并与其他基因结合可能是一种宝贵的抗性来源。