Mining and genomic characterization of resistance to tan spot, Stagonospora nodorum blotch (SNB), and Fusarium head blight in Watkins core collection of wheat landraces
Mining and genomic characterization of resistance to tan spot, Stagonospora nodorum blotch (SNB), and Fusarium head blight in Watkins core collection of wheat landraces
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DOI：
10.1186/s12870-019-2093-3
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发表时间：
2019-11-08
影响因子：
5.3
通讯作者：
Sehgal, Sunish K.
中科院分区：
文献类型：
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作者：
Halder, Jyotirmoy;Zhang, Jinfeng;Sehgal, Sunish K.
20世纪20年代末，A. E.沃特金斯收集了大约7000个面包小麦地方品种（LC）。来自全球32个不同的国家。其中有826个LCs保持活力，可作为提高小麦抗病性的上级/有利等位基因的重要来源。在本研究中，一个核心集的121个LC，它捕获了大部分的遗传多样性的沃特金斯收集，进行了评估，以确定新的来源，抗褐斑病，Stagonospora nodorum blotch（SNB），镰刀菌头枯病（FHB）。大部分的LCs对小麦褐斑病Ptr 1号生理小种（84%）和FHB（96%）中度敏感，而大部分的LCs对小麦褐斑病Ptr 5号生理小种（95%）和SNB（54%）具有抗性或中度抗性。在本研究中鉴定出13个LCs可能是对小麦褐斑病Ptr 1号和5号生理小种以及SNB的多重抗性来源，另外5个LCs可能是对赤霉病的潜在抗性来源。使用疾病表型评分和118个LC的8807个SNP数据进行GWAS分析，其鉴定了30个显著的标记-性状关联（MTA），-log 10（p值）>3.0。在这项研究中，分别发现10个、5个和5个基因组区域与对褐斑病Ptr小种1、小种5和SNB的抗性相关。除Tsn 1外，还鉴定了几个新的基因组区域Q.Ts1.sdsu-4 BS和Q.Ts1.sdsu-5 BS（tan spot Ptr生理小种1）以及Q.Ts5.sdsu-1BL、Q.Ts5.sdsu-2DL、Q.Ts5.sdsu-3AL和Q.Ts5.sdsu-6 BL（tan spot Ptr生理小种5）。我们的研究结果表明，这些推定的基因组区域包含几个基因，发挥重要作用，在植物防御mechanism.ConclusionOur的结果表明，存在有价值的抗性等位基因对叶斑病在沃特金LC。与小麦抗赤星病和抗黑条病数量性状基因座（QTL）连锁的单核苷酸多态性（SNP）标记沿着与小麦多重抗病性相关的多基因标记可为小麦育种提供参考。
BackgroundIn the late 1920s, A. E. Watkins collected about 7000 landrace cultivars (LCs) of bread wheat (Triticum aestivum L.) from 32 different countries around the world. Among which 826 LCs remain viable and could be a valuable source of superior/favorable alleles to enhance disease resistance in wheat. In the present study, a core set of 121 LCs, which captures the majority of the genetic diversity of Watkins collection, was evaluated for identifying novel sources of resistance against tan spot, Stagonospora nodorum blotch (SNB), and Fusarium Head Blight (FHB).ResultsA diverse response was observed in 121 LCs for all three diseases. The majority of LCs were moderately susceptible to susceptible to tan spot Ptr race 1 (84%) and FHB (96%) whereas a large number of LCs were resistant or moderately resistant against tan spot Ptr race 5 (95%) and SNB (54%). Thirteen LCs were identified in this study could be a valuable source for multiple resistance to tan spot Ptr races 1 and 5, and SNB, and another five LCs could be a potential source for FHB resistance. GWAS analysis was carried out using disease phenotyping score and 8807 SNPs data of 118 LCs, which identified 30 significant marker-trait associations (MTAs) with -log10 (p-value) >3.0. Ten, five, and five genomic regions were found to be associated with resistance to tan spot Ptr race 1, race 5, and SNB, respectively in this study. In addition to Tsn1, several novel genomic regions Q.Ts1.sdsu-4BS and Q.Ts1.sdsu-5BS (tan spot Ptr race 1) and Q.Ts5.sdsu-1BL, Q.Ts5.sdsu-2DL, Q.Ts5.sdsu-3AL, and Q.Ts5.sdsu-6BL (tan spot Ptr race 5) were also identified. Our results indicate that these putative genomic regions contain several genes that play an important role in plant defense mechanisms.ConclusionOur results suggest the existence of valuable resistant alleles against leaf spot diseases in Watkins LCs. The single-nucleotide polymorphism (SNP) markers linked to the quantitative trait loci (QTLs) for tan spot and SNB resistance along with LCs harboring multiple disease resistance could be useful for future wheat breeding.