Ug99 (TTKSK) and Digalu (TKTTF) race groups of f. sp (), are thought to be the most virulent, rendering many wheat stem rust resistance genes () ineffective. A total of 600 single pustule isolates were collected from eight Egyptian provinces during 2016–2022, undergoing both phenotyping and genotyping assays. Among these, 129 viable samples (v-samples) underwent phenotyping using the North American differentials delineated to races in the TTKS (Ug99) and TKTTF race groups, identifying 24 distinct physiologic races of . Notably, seven virulent races, TKTTF (Digalu), TKKTF, TKPTF, TKKTP, TTRTF, TTTTF, and TKFTF, were discovered in Egypt. The host reaction of wheat germplasm to these seven races indicated a high level of susceptibility. A set of 437 dead samples (d-samples) of isolates from Egypt were genotyped using newly created 17 core SNP markers. Genotypic analysis revealed that these seven races could be classified into two major clades: III and IV. Within these clades, six subclades were identified, namely III-B, IV-A.2, IV-B, IV-E.1, IV-E.2, and IV-F. These SNP genotypes exhibited a broad geographic distribution, highlighting the global movement of populations across Europe, Asia, and Africa. Notably, none of these genetic groups were present in Egypt before 2016. The most prevalent genotypes were subclades IV-A.2 (TKTTF; Digalu), IV-E.2 (TKKTF, TKPTF, TKFTF), and III-B (TTRTF). The prevalence of these unique genotypes/races suggests clonal reproduction and evolution within them. Race TKKTP (subclade IV-E.1) is particularly concerning because of its ability to overcome the resistance conferred by gene against race TTKSK (Ug99). Phylogenetic analysis of genetic groups revealed that the majority of identified races belong to TKTTF (Digalu) race group (subclade IV-A.2). Notably, no races were found to belong to the TTKS (Ug99) race group (clade I). This information should help breeders select a broader range of resistance genes that are both diverse and effective to enhance the durability of stem rust resistance.

中文翻译：

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禾本科柄锈菌强毒种的系统发育。 sp。小麦基于表型和基因分型，使用新开发的 SNP 标记对进化枝中的遗传群体进行分析

Ug99 (TTKSK) 和 Digalu (TKTTF) 比赛组 f. sp ()，被认为是毒性最强的，导致许多小麦茎锈病抗性基因 () 失效。 2016 年至 2022 年期间，从埃及 8 个省份收集了总共 600 个脓疱分离株，并进行了表型和基因分型测定。其中，129 个活样本（v 样本）使用 TTKS (Ug99) 和 TKTTF 种族组中的北美种族差异进行了表型分析，鉴定了 24 个不同的生理种族。值得注意的是，在埃及发现了七个剧毒种族：TKTTF (Digalu)、TKKTF、TKPTF、TKKTP、TTRTF、TTTTF 和 TKFTF。小麦种质对这七个小种的宿主反应表明了高度的易感性。使用新创建的 17 个核心 SNP 标记对来自埃及的 437 个死亡分离株样本（d 样本）进行了基因分型。基因型分析显示，这七个种族可分为两个主要分支：III 和 IV。在这些进化枝中，确定了 6 个亚进化枝，即 III-B、IV-A.2、IV-B、IV-E.1、IV-E.2 和 IV-F。这些 SNP 基因型表现出广泛的地理分布，突出了欧洲、亚洲和非洲人口的全球流动。值得注意的是，这些基因组在 2016 年之前都不存在于埃及。最常见的基因型是 IV-A.2 分支（TKTTF；Digalu）、IV-E.2（TKKTF、TKPTF、TKFTF）和 III-B（TTRTF） ）。这些独特基因型/种族的普遍存在表明它们内部存在克隆繁殖和进化。 TKKTP 种族（IV-E.1 支系）尤其令人担忧，因为它能够克服 TTKSK (Ug99) 基因所赋予的抗性。遗传群体的系统发育分析表明，大多数已识别的种族属于 TKTTF (Digalu) 种族群体（亚支 IV-A.2）。值得注意的是，没有发现任何种族属于 TTKS (Ug99) 种族组（分支 I）。这些信息应有助于育种者选择更广泛的抗性基因，这些抗性基因既多样化又有效，以增强茎锈病抗性的持久性。