Systems Biology Approaches Enhance Trait Dissection and Potential for Improvement of Agronomic and Nutritional Qualities in Oat

One of the promises of systems biology is to accelerate the pace of trait dissection and improvement, via the simultaneous examination of the metabolome, phenome and genome. Here we describe the characterization of a 1,000-member oat germplasm panel selected from the AFRI Core and National Small Grains Collections, supplemented by families created for specialty composition traits, using systems biology tools. First, the complete collection was genotyped using GBS to generate a dense genetic map suitable for genome wide association studies (GWAS) and genomic selection. Second, a 500-member subset was selected for agronomic evaluation on two farms using an incomplete block design, which contained single entries for most lines but with 2 check varieties to help account for experimental and environmental variance. Heading date, susceptibility to Puccinia coronata f.sp. avenae, height and lodging,  were evaluated. Third, this 500-member subset was examined using both gas and liquid chromatography separation methods coupled with mass spectrometry to estimate the metabolome of mature, naked oats. These data were organized and visualized using a weighted network correlation analysis, to condense the ~1,000 features detected by mass spectrometry into co-regulated modules. This procedure reduces data complexity and provides an entry point for GWAS and other genetic analyses. We will present a case study that describes the connection between the avenanthramides, a group of phenolic antioxidants, and resistance to P. coronata.