Besides the mode of inheritance, the knowledge of the chromosome location and allelic relationships are the essentials towards a successful deployment and stacking of divergent disease resistance genes for a given pathogen in breeding programs. Powdery mildew of oats, to which 11 major resistance genes in the host Avena sativa L. have been characterized so far, is a prevalent fungal disease of the crop in Northwestern Europe. In the present study, the resistance gene Pm3 was mapped by linkage analysis relative to molecular markers from oat consensus linkage group Mrg18 which was recently determined to represent oat chromosome 1A. Pm3 was located at 67.7–72.6 cM on Mrg18 of the oat consensus map, a position at which also stem and crown rust resistance genes Pg13 and Pc91 and a large cluster of resistance gene analogs have been previously mapped. The closely linked marker GMI_ES03_c2277_336 was found to be useful for the prediction of Pm3 in gene postulation studies. Although the major effect of the widespread gene got lost over time, the known genome location with associated markers will assist revealing in future genetic studies whether there is a possible residual effect of the gene contributing to adult plant resistance.

除了遗传模式外，染色体位置和等位基因关系的知识对于在育种程序中成功部署和堆叠给定病原体的不同抗病基因也是必不可少的。迄今已鉴定出燕麦白粉病的寄主Avena sativa L.的11个主要抗性基因是燕麦，是西北欧洲农作物的一种常见真菌病。在本研究中，抗性基因Pm3通过连锁分析相对于燕麦共有连锁群Mrg18的分子标记进行了定位，该分子最近被确定代表燕麦1A染色体。Pm3在燕麦共有图谱的Mrg18上位于67.7–72.6 cM，该位置也是茎和冠锈病抗性基因Pg13和Pc91以及大量抗药性基因类似物先前已被定位。发现紧密关联的标记GMI_ES03_c2277_336可用于预测基因假设研究中的Pm3。尽管随着时间的流逝，广泛传播的基因的主要作用消失了，但是具有相关标记的已知基因组位置将有助于在未来的遗传研究中揭示该基因是否可能对成年植物产生抗药性。