Characterization of Yr54 and other genes associated with adult plant resistance to yellow rust and leaf rust in common wheat Quaiu 3

• Published in: Molecular breeding 2014-02, Vol.33 (2), p.385-399
• Main Authors: Basnet, B. R, Singh, R. P, Ibrahim, A. M. H, Herrera-Foessel, S. A, Huerta-Espino, J, Lan, C, Rudd, J. C
• Format: Article
• Language: English
• Subjects: adults; Biomedical and Life Sciences; Biotechnology; Chromosomes; corn; field experimentation; Gene mapping; Genes; genetic markers; Immunity; inbred lines; Inbreeding; Leaf rust; Leaves; Life Sciences; loci; Mapping; Markers; Molecular biology; phenotypic variation; Phenotypic variations; Plant biology; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant resistance; Plant Sciences; Puccinia recondita; Puccinia striiformis; Puccinia triticina; Quantitative trait loci; races; Seedlings; Stripe rust; Triticum aestivum; Wheat; Zea mays
• ISSN: 1380-3743; 1572-9788
• DOI: 10.1007/s11032-013-9957-2

Leaf rust (LR) and yellow rust (YR), caused by Puccinia triticina and Puccinia striiformis f. sp. tritici, respectively, are important diseases of wheat. Quaiu 3, a common wheat line developed at the International Maize and Wheat Improvement Center (CIMMYT), is immune to YR in Mexico despite seedling susceptibility to predominant races. Quaiu 3 also shows immunity to LR in field trials and is known to possess the race-specific gene Lr42. A mapping population of 182 recombinant inbred lines (RILs) was developed by crossing Quaiu 3 with susceptible Avocet-YrA and phenotyped with LR and YR in field trials for 2 years in Mexico. Quantitative trait loci (QTL) associated with YR and LR resistance in the RILs were identified using Diversity Arrays Technology and simple sequence repeat markers. A large-effect QTL on the long arm of chromosome 2D explained 49–54 % of the phenotypic variation in Quaiu 3 and was designated as Yr54. Two additional loci on 1BL and 3BS explained 8–17 % of the phenotypic variation for YR and coincided with previously characterized adult plant resistance (APR) genes Lr46/Yr29 and Sr2/Yr30, respectively. QTL on 1DS and 1BL corresponding to Lr42 and Lr46/Yr29, respectively, contributed 60–71 % of the variation for LR resistance. A locus on 3D associated with APR to both diseases explained up to 7 % of the phenotypic variance. Additional Avocet-YrA-derived minor QTL were also detected for YR on chromosomes 1A, 3D, 4A, and 6A. Yr54 is a newly characterized APR gene which can be combined with other genes by using closely linked molecular markers.