Identification of Mixed Linkage β-glucan Quantitative Trait Loci in Hexaploid Oat

Hexaploid oat, Avena sativa (2n=6x=42) is a commercially important cereal in the Poaceae family with many human health benefits. Among the cereal grains, oats contain one of the highest levels of (1-3,1-4)-β-D-glucan (β-glucan). Identifying regions of the genome that are associated with β-glucan accumulation can lead to identification of genes involved in β-glucan accumulation as well as provide a useful resource for breeders. We performed genome wide association studies (GWAS) on a total of 579 accessions across three diverse data sets grown in two or three locations.  Each data set was genotyped using 1,772 to 2,524 markers. A mixed model approach was used to control for population structure that took into account both principle component analysis and kinship analysis. Significant markers were filtered by selecting only significant loci that were replicated across locations and/or studies. One of the remaining QTL regions on mrg12 was of particular interest with 9 significant markers across a 6.5 cM region replicated in all three studies and two of the three locations.