Quantitative Trait Loci Affecting Oil Content, Oil Composition, and Other Agronomically Important Traits in Oat

Abstract

Groat oil content and composition are important determinants of oat ( Avena sativa L.) quality. We investigated these traits in a population of 146 recombinant inbred lines from a cross between ‘Dal’ (high oil) and ‘Exeter’ (low oil). A linkage map consisting of 475 Diversity Arrays Technology (DArT) markers spanning 1271.8 cM across 40 linkage groups was constructed. Quantitative trait locus (QTL) analysis for groat oil content and composition was conducted using grain samples grown at Aberdeen, ID, in 1997. Quantitative trait locus analysis for multiple agronomic traits was also conducted using data collected from hill plots and field plots in Ottawa, ON, in 2010. Using simple and composite interval mapping methods, QTLs for oil content, palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), and linolenic acid (18:3) were identified. Two of the loci associated with oil content were associated with all of the fatty acids examined in this study, and most oil‐related QTL showed similar patterns of effect on the fatty acid profile. These results suggest the presence of pleiotropic effects on oil‐related traits through influences at specific nodes of the oil synthesis pathway. In addition, 12 QTL‐associated markers (likely representing nine unique regions) were associated with plant height, heading date, lodging, and protein content.