Exploring arabinoxylans in durum wheat: Contrasting genotypes and environments across different crop seasons

Abstract

Wheat is a major source of dietary fibers (DF), with arabinoxylans (AX) being the primary component found in cell walls. Apart from structural functions, AX also influence the technological and nutritional properties of wheat-based foods. Nevertheless, it is still unclear how changes in the wheat growing environment could impact AX composition and concentration. The objective of this research is to enhance our understanding of wheat AX variability as determined by abiotic stress, and to better understand the impact that the genotype, the environment, and their interaction have on this component’s variation. A set 6 durum wheat (DW) samples with contrasting quality characteristics were grown across 3 cropping seasons (2014-2015, 2015-16 and 2016-17) in Ciudad Obregón, Sonora, under 7 environments: 3 environments with no heat or drought stress but different plot size and growing conditions (flat vs bed); intermediate and severe drought; and early or late heat. Total (TOT-AX) and water-souble AX (WE-AX) fractions were measured in duplicate. ANOVA showed significant genotype × environment interactions across all conditions. Intermediate drought was the most stable environment for both fiber fractions. PCA indicated Mexicali had the lowest, and Cirno the highest, variability across environments. Based on these preliminary results it is clear that both the growing cycle, the genotype and their interaction, play a role in the quantity and quality variation of the AX. Further work on the same wheat samples grown under drought and heat stress will help reveal the effect that these stresses have on the biosynthesis of AX.2 pag