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The genetic control of adult plant resistance to Stagonospora nodorum blotch (SNB) is complex, consisting of genes with minor effects interacting in an additive manner. Earlier studies detected quantitative trait loci (QTL) for flag leaf resistance in successive years on chromosomes 1B, 2A, 2D, and 5B using SSR- and DArT-based genetic maps of progeny from the crosses EGA Blanco/Millewa, 6HRWSN125/WAWHT2074, and P92201D5/P91193D1. Similarly, QTL for glume resistance detected in successive years and multiple environments were identified on chromosomes 2D and 4B from genetic maps of P92201D5/P91193D1 and 6HRWSN125/WAWHT2074, respectively. The SSR- and DArT-based genetic maps had an average distance of 6.5, 7.8, and 9.7 cM between marker loci for populations EGA/Millewa, P92201D5/P91193D1, and 6HRWSN125/WAWHT2074, respectively. This study used single nucleotide polymorphism (SNP) markers from the iSelect Infinium 90K genotyping array to fine-map genomic regions harbouring QTL for flag leaf and glume SNB resistance, reducing the average distance between markers to 2.9, 3.3, and 3.4 cM for populations P92201D5/P91193D1, EGA/Millewa, and 6HRWSN125/WAWHT2074, respectively. Increasing the marker density of the genetic maps with SNPs did not identify any new QTL for SNB resistance but discriminated previously identified co-located QTL into separate but closely linked QTL. Key words: Stagonospora nodorum blotch, quantitative trait loci, adult plant resistance, single nucleotide polymorphism. Le controle genetique de la resistance a la septoriose (Stagonospora nodorum blotch, SNB) est complexe et comprend des genes a effets mineurs qui agissent de maniere additive. Des etudes anterieures ont detecte des QTL pour la resistance chez la feuille etendard au cours d'annees successives sur les chromosomes 1B, 2A, 2D et 5B a l'aide de cartes genetiques basees sur des marqueurs SSR et DArT, lesquelles avaient ete produites a partir des croisements EGA Blanco/Millewa, 6HRWSN125/WAWHT2074 et P92201D5/P91193D1. Similairement, des QTL pour la resistance des glumes ont ete detectes sur plusieurs annees et dans de multiples environnements sur les chromosomes 2D et 4B au sein de cartes genetiques pour les croisements P92201D5/P91193D1 et 6HRWSN125/WAWHT2074, respectivement. Les cartes basees sur les marqueurs SSR et DArT presentaient une distance moyenne entre les marqueurs de 6,5, 7,8 et 9,7 cM chez les populations EGA/Millewa, et P92201D5/P91193D1 et 6HRWSN125/WAWHT2074, respectivement. Cette etude a employe les marqueurs mononucleotidiques (SNP) de la puce iSelect Infinium 90K pour cartographier plus finement les regions contenant des QTL pour les deux formes de resistance a la septoriose (feuille etendard et glume) grace a une distance moyenne reduite entre les marqueurs (2,9, 3,3 et 3,4 cM chez les cartes P92201D5/P91193D1, EGA/Millewa et 6HRWSN125/WAWHT2074, respectivement). Cet accroissement de la densite des marqueurs au sein des cartes genetiques a l'aide des SNP n'a pas permis d'identifier de nouveaux QTL pour la resistance a la septoriose, mais a permis de distinguer des QTL proches qui etaient anterieurement consideres comme n'en formant qu'un seul. [Traduit par la Redaction] Mots-cles: septoriose, locus de caractere quantitatif, resistance a l'age adulte, polymorphisme mononucleotidique., Introduction Stagonospora nodorum blotch (SNB) is a nercrotophic fungal disease of wheat caused by the pathogen Parastagonospora nodorum (synonyms Stagonospora nodorum, Phaeosphaeria nodorum). Symptoms of infection in adult plants generally [...]

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