Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/2006
Publication Date: 12/1/2006
Citation: Finnie, S.M., Bettge, A.D., Morris, C.F. 2006. Influence of cultivar and environment on water-soluble and water-insoluble arabinoxylans in soft wheat. Cereal Chemistry 83(6):617-623. Interpretive Summary: Arabinoxylans are nonstarch polysaccharides found in wheat. Arabinoxylans have hydrophilic characteristics, which can impact the end-use quality of food products produced with wheat through modification of water relations. Arabinoxylans are functionally divided into the classes of water-soluble and insoluble. Insoluble arabinoxylans are associated with cell wall structure, while soluble arabinoxylans have been shown to affect flour end-use quality. We discovered that the concentration of water-soluble class of arabinoxylans in wheat is mainly determined genetically, while the growing environment had a relatively minor influence. We further demonstrated the water-insoluble arabinoxylan fraction is more influenced by the growing environment. These results will help wheat breeders develop wheat varieties that have a target arabinoxylan content. Since the water-soluble arabinoxylan fraction is under genetic control, the potential exists for new varieties with targeted water-soluble arabinoxylans that have better end-use functionality.
Technical Abstract: Arabinoxylans are hydrophilic non-starch polysaccharides found in wheat grain as minor constituents. Arabinoxylans can associate with large amounts of water through hydrogen bonding and can form oxidative gels. These properties are important factors in end-use quality of wheat. The objective of this study was to delineate the influence of wheat variety and growing environment on variation in water-soluble (WS-AX), water-insoluble (WI-AX) and total (TO-AX) arabinoxylan contents of flour and whole-grain meal. This study included seven spring and 20 winter soft white wheat varieties grown in 10 and 12 environments, respectively (each evenly split over two crop years). Univariate (ANOVA) and multivariate analysis of variance with canonical analysis (MANOVA) was used to evaluate sources of variation. Variation in arabinoxylan contents and absolute amounts (xylose equivalents) among the two variety sample sets (spring and winter) was similar, and both variety and environment were significant sources of variation. Variety by environment interaction was relatively unimportant. Results indicate that the variation in arabinoxylan content is primarily influenced by variety and secondarily influenced by environment. Within arabinoxylan fractions, WS-AX content is primarily influenced by genotype, while WI-AX content is more greatly influenced by the environment.