Powdery mildew is a barley foliar disease that causes great loss in yield. Because of the limited number of effective resistance genes, efforts to identify new sources of resistance are frequently focused on genetically diversified landraces. The goal of this study was to characterise the powdery mildew resistance gene in barley line 2553-3 selected from the Moroccan landrace. Phytopathological testing against a set of differential pathogen isolates revealed different pattern responses of this gene from those of other known resistance genes. F₂ and F_2:3 (2553-3 × Manchuria) mapping populations were employed to investigate resistance inheritance. Two approaches were applied for the linkage analysis: in the first approach, 22 resistant and 21 susceptible homozygous F₂ plants genotyped by the DArTseq platform (Diversity Arrays Technology, Pty. Ltd.) were used; in the second, 94 F₂ plants were genotyped by converted DArTseq markers and SSRs. Both analyses delineated a new resistance gene on the short arm of chromosome 2H. The authors propose MlMor as a gene symbol for newly characterized powdery mildew resistance genes in barley line 255-3-3. The results presented herein provide a good foundation for the development of closer linkage markers and MAS breeding.

中文翻译：

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在摩洛哥的一个大麦地方品种中鉴定了一个新的抗白粉病基因。

白粉病是一种大麦叶病，会导致产量大幅下降。由于有效抗性基因的数量有限，寻找新的抗性来源的努力通常集中在遗传多样化的地方品种上。这项研究的目的是鉴定选自摩洛哥地方品种的大麦系2553-3中的白粉病抗性基因。针对一组不同的病原体分离物进行的植物病理学测试显示，该基因与其他已知抗性基因的模式响应不同。使用F ₂和F _2：3（2553-3×Manchuria）作图种群调查抗性遗传。有两种方法用于连锁分析：在第一种方法中，有22种抗药性和21种易感纯合子F ₂使用通过DArTseq平台（Diversity Arrays Technology，Pty.Ltd。）进行基因分型的植物；在第二个中，通过转化的DArTseq标记和SSR对94个F ₂植物进行基因分型。两项分析均在2H染色体的短臂上描绘了一个新的抗性基因。作者提出将MlMor作为大麦系255-3-3中新近鉴定的白粉病抗性基因的基因符号。本文介绍的结果为开发更紧密的连锁标记和MAS育种奠定了良好的基础。