Relationships among Agronomic Traits and Grain Composition in Oat Genotypes Grown in Different Environments

Abstract

Genotype and environment are major determinants of plant phenotype. Economically important quantitative traits include agronomic characteristics and grain composition. This study examined relationships among agronomic traits and grain composition as influenced by genotype and environment. Thirty‐three oat (Avena sativa L.) genotypes were grown in three trials in Idaho (Aberdeen irrigated, Tetonia irrigated, and Tetonia dryland) in three consecutive years (1999–2001). Yield, heading date, kernel physical characteristics, and concentrations of groat protein, β‐glucan, oil, tocols, and avenanthramides were measured. Analysis of the combined data for all environments showed significant genotypic differences for all traits except avenanthramide 2f Most of the variance was associated with genotype for all traits except yield, α‐tocopherol, and the avenanthramides. The genotype × trial interaction was significant only for avenanthramides concentration, whereas the genotype × year interaction was significant for most traits. Principal component analysis biplots illustrate that for protein and oil there was a clear difference between 2000 and the other years. Some genotypes were stable across environments; others responded differently in different environments. Correlation analysis showed several close associations among traits: avenanthramides were correlated with β‐glucan, and oil was negatively correlated with groat physical characteristics and with avenanthramide 2f The results show that knowledge of the relationships among traits and environments can assist breeders in optimizing both agronomic traits and grain composition simultaneously.