TOCOLS IN HULL-LESS AND HULLED BARLEY GENOTYPES GROWN IN CONTRASTING ENVIRONMENTS

Abstract The content of tocols is a parameter of increasing interest in evaluating the quality of plant-based food. Cereal grains are amongst the most widely occurring plant food components and their potential for enriching the content of vitamin E and/or hypocholesterolemic active compounds in food is therefore of interest. We investigated the presence of tocol homologues in hulled and hull-less barley, as influenced by genotype and location. Both factors significantly influenced the amount of tocols in the barley kernel, with genotype having the greater effect for most homologues. Significant genotype×location interaction was observed for six out of eight homologues, but not for total tocotrienols and total tocols; however, the coefficient of determination for genotype was high for most homologues, so that selection for this traits should be possible. The hull-less trait negatively affected the content of total tocols, influencing both tocopherols (positively) and tocotrienols (negatively). Statistical analysis suggests this is due to a different sub-set of homologues, which is preferentially accumulated in hull-less vs. hulled barleys. As hulled barley had a greater accumulation of more bioactive homologues, the selection of hull-less barleys for this trait should be considered for enhancing food quality.