Stem rust is an important disease of cultivated oat (Avena sativa) caused by Puccinia graminis f. sp. avenae. In North America, host resistance is the primary strategy to control this disease and is conferred by a relatively small number of resistance genes. Pg2 is a widely deployed stem rust resistance gene that originates from cultivated oat. Oat breeders wish to develop cultivars with multiple Pg genes to slow the breakdown of single gene resistance, and often require DNA markers suited for marker-assisted selection. Our objectives were to (i) construct high density linkage maps for a major oat stem rust resistance gene using three biparental mapping populations, (ii) develop Kompetitive allele-specific PCR (KASP) assays for Pg2-linked single-nucleotide polymorphisms (SNPs), and (iii) test the prediction accuracy of those markers with a diverse panel of spring oat lines and cultivars. Genotyping-by-sequencing SNP markers linked to Pg2 were identified in an AC Morgan/CDC Morrison recombinant inbred line (RIL) population. Pg2-linked SNPs were then analyzed in an AC Morgan/RL815 F₂ population and an AC Morgan/CDC Dancer RIL population. Linkage analysis identified a common location for Pg2 in all three populations on linkage group Mrg20 of the oat consensus genetic map. The most predictive markers were identified and converted to KASP assays for use in oat breeding programs. When used in combination, the KASP assays for the SNP loci avgbs2_126549.1.46 and avgbs_cluster_23819.1.27 were highly predictive of Pg2 status in panel of 54 oat breeding lines and cultivars.

茎锈病是由Puccinia graminis f引起的栽培燕麦（Avena sativa）的一种重要疾病。sp。avenae。在北美，宿主抗性是控制这种疾病的主要策略，并且抗性基因的数量相对较少。Pg2是一种广泛部署的源自种植燕麦的抗茎锈基因。燕麦育种者希望开发具有多种Pg的品种这些基因可以减缓单个基因抗性的破坏，并且通常需要适合标记辅助选择的DNA标记。我们的目标是（i）使用三个双亲作图群体构建主要燕麦茎锈病抗性基因的高密度连锁图谱;（ii）为Pg2连锁的单核苷酸多态性（SNP）开发竞争竞争性等位基因特异性PCR（KASP）分析方法（iii）使用各种春季燕麦品种和品种测试这些标记的预测准确性。在AC Morgan / CDC Morrison重组自交系（RIL）群体中鉴定了与Pg2连锁的SNP标记基因分型。然后在AC Morgan / RL815 F _2中分析Pg2连接的SNP人口和AC Morgan / CDC舞者RIL人口。连锁分析确定了燕麦共有遗传图谱上Mgr20连锁群上所有三个种群中Pg2的共同位置。确定了最具预测性的标记，并将其转换为用于燕麦育种计划的KASP测定法。当组合使用时，针对SNP位点avgbs2_126549.1.46和avgbs_cluster_23819.1.27的KASP分析可高度预测54个燕麦育种系和品种的Pg2状态。