Location: Hard Winter Wheat Genetics ResearchTitle: Genome-Wide Associations for Multiple Pest Resistances in a Northwestern United States Elite Spring Wheat Panel Author
Submitted to: PLoS One
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/9/2018
Publication Date: N/A
Citation: N/A Interpretive Summary: In this study, we collected 408 elite spring wheat lines from the Pacific Northwest region to test their responses to diseases including stripe rust, Septoria tritici blotch, and the insect pest, Hessian fly. The wheat lines were also analyzed for genetic markers across the whole genome. Resistance genes were identified for stripe rust (38 genes), Septoria tritici blotch (8 genes) and Hessian fly (9 genes). Some of the associated genes corresponded with previously reported gene locations, but a few new resistance genes were also identified for each trait. Newly identified resistance genes, along with better genetic markers, will help future breeding and marker-assisted selection efforts to develop cultivars that are resistant to these pests.
Technical Abstract: Northern areas of the western United States are one of the most productive wheat growing regions in the United States. Increasing productivity through breeding is hindered by several biotic stresses which slow and constrain targeted yield improvement. In order to understand genetic variation for stripe rust (Puccinia striiformis f. sp. tritici), Septoria tritici blotch (Mycosphaerella graminicola), and Hessian fly (Mayetiola destructor) in regional germplasm, a panel of 408 elite spring wheat lines was characterized and genotyped with a Illumina 9K wheat single nucleotide polymorphism (SNP) chip to enable genome-wide association study (GWAS) analyses. Significant marker-trait associations were identified for stripe rust (38 loci), Septoria tritici blotch (8) and Hessian fly (9) resistance. Many of the QTL corresponded with previously reported gene locations or QTL, but we also discovered new resistance loci for each trait. We validated one of the stripe rust resistance loci detected by GWAS in a bi-parental mapping population, which confirmed the detection of Yr15 in the panel. This study elucidated well-defined chromosome regions for multiple pest resistances in elite Northwest germplasm. Newly identified resistance loci, along with SNPs more tightly linked to previously reported genes or QTL will help future breeding and marker assisted selection efforts.