|Esvelt Klos, Kathy|
|YIMER, BELAYNEH - Orise Fellow|
|BEATTIE, AARON - University Of Saskatchewan|
|CHONG, JAMES - Agriculture And Agri-Food Canada|
|HARRISON, STEPHEN - Louisiana State University|
|IBRAHIM, AMIR M - Texas A&M Agrilife|
|KOLB, FREDERIC - University Of Illinois|
|MCCARTNEY, CURT - Agriculture And Agri-Food Canada|
|MCMULLEN, MICHAEL - North Dakota State University|
|MITCHELL FETCH, JENNIFER - Agriculture And Agri-Food Canada|
|MOHAMMADI, MOHSEN - Purdue University|
|MURPHY, J. - North Carolina State University|
|TINKER, NICK - Agriculture And Agri-Food Canada|
Submitted to: The Plant Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2017
Publication Date: 4/27/2017
Citation: Esvelt Klos, K.L., Yimer, B.A., Babiker, E.M., Beattie, A.D., Bonman, J.M., Carson, M.L., Chong, J., Harrison, S.A., Ibrahim, A.H., Kolb, F.L., McCartney, C.A., McMullen, M., Mitchell Fetch, J., Mohammadi, M., Murphy, J.P., Tinker, N.A. 2017. Genome-wide association mapping of crown rust resistance in oat elite germplasm. The Plant Genome. doi: 10.3835/plantgenome2016.10.0107.
Interpretive Summary: Crown rust is the most important disease of oats in North America, causing reduction in both forage quality and grain yield. In most oat production areas, genetic resistance is the primary means of controlling crown rust, but seedling resistance genes remain effective for only about 5 years on average before virulence develops in the pathogen and new sources of seedling and adult plant resistance are needed. We identified the genomic location of genes contributing to crown rust resistance in current elite oat germplasm. We find that among these genomic regions are some that contain previously mapped resistance genes and some that have not been previously reported. The associated molecular markers may be suitable for use in marker-assisted selection for crown rust resistance, or may be used to define a genomic region for comparative sequence analysis to identify additional markers. Such markers will help plant breeders develop new, disease resistant oat varieties for U.S. growers.
Technical Abstract: Oat crown rust, caused by Puccinia coronata f. sp. avenae, is a major constraint to oat production in many parts of the world. In this first comprehensive multi-environment genome-wide association map of oat crown rust, we used 2,972 SNPs genotyped on 631 oat lines for association mapping of quantitative trait loci (QTL). Seedling reaction to crown rust in these lines was assessed as infection type (IT) with each of 10 crown rust isolates. Adult plant reaction was assessed in the field in a total of 10 location-years as percent severity (SV), and as infection reaction (IR) in a 0 to 1 scale. Overall, 29 SNPs on 12 linkage groups were predictive of crown rust reaction in at least one experiment at a genome-wide level of statistical significance. The QTL identified here include those in regions previously shown to be linked with seedling resistance genes Pc48, Pc58a, Pc68, Pc71, Pc91, and PcKM; and also with adult plant resistance and adaptation-related QTL. In addition, QTL on linkage groups Mrg03, Mrg08, and Mrg23 were identified in regions not previously associated with crown rust resistance. Evaluation of marker genotypes in a set of crown rust differential lines supported Pc91 as the identity of QPc.CORE.18.3. SNPs with rare alleles associated with lower disease scores may be suitable for use in marker-assisted selection of oat lines for crown rust resistance.