Cultivation environment affects antioxidants, protein and oil content of oat genotypes differently

Abstract

Antioxidant compounds, avenanthramides and tocols, in oat (Avena sativa L.) may have health-promoting effects on mammals including humans. Content and composition of these substances can be affected by genotype as well as environment. The aim of this study was to determine the differential effect of growth environment on the phenotype composition of oat genotypes adapted to different geographical areas. Twenty-two genotypes, nine bred in Canada, nine in the USA and four in Sweden, were cultivated in 2003 at four sites, Saskatoon, Canada (S), Madison, USA (M) and Jönköping (J) and Köping (K), Sweden. The harvested grains were dehulled and analysed for content and composition of avenanthramides and tocols, as well as content of oil and protein. There were significant differences between sites, genotypes and the site x genotype interaction for the major avenanthramides, 2c, 2p and 2f, total avenanthramides, protein and oil content. Significant differences were also found for tocols. Avenanthramide contents of oats grown at sites M and K were significantly higher than from sites J and S. Oats from site J had significantly higher content of avenanthramides than from site S and higher oil content than samples from all other sites. Oats from sites J and M were higher in protein content than those from K and S. The cultivar Belle (USA) and the Canadian line LAO-597-NZ-0544 had significantly higher avenanthramide content than all other genotypes, while the Swedish cultivar Matilda had the highest oil content and together with Gem (USA) the highest protein content. Genotypes when grown in environments to which they are unadapted often had different avenanthramide content than when grown in their adapted location. The significant interactions indicated that genotypes did not respond similarly to different environments and that avenanthramide content may be an expression of genetic adaptation to the environment.