Influence of the Hulless, Waxy Starch and Short-awn Genes on the Composition of Barleys

Author： Xue Q. Wang L. Newman R.K. Newman C.W. Graham H.

ISSN： 0733-5210

Source： Journal of Cereal Science, Vol.26, Iss.2, 1997-09, pp. : 251-257

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

The objectives of this study were to determine the effects of genotype on chemical components of barley which influence nutritional value. Six barley (Hordeum vulgare L.) isotypes, expressed in Compana (CI 5438) and Betzes (CI 6398) cultivars with genetic combinations non-waxy (WXWX ) and waxy (wxwx) starch in covered (NN ) and hulless (nn) kernels and long-awn (LK2LK2) and short-awn (lk2lk2) traits, were grown in 1987, 1988 and 1989. Analyses were made for protein, fat, starch, free sugars, total dietary fibre (TDF ), TDF components and extract viscosity. The hulless gene reduced TDF by preventing the hulls from adhering to the kernel, thus concentrating the remaining components. Waxy barleys contained less (P<0·001) starch, but more (P<0·001) free sugars and ether extract (P<0·001). Increased (P<0·02) TDF in waxy barleys was due to an increase (P<0·001) in total and soluble beta-glucans. The short-awn gene had no effect other than to increase (P<0·04) extract viscosity, and to reduce test weight (P<0·008) and % plump kernels (P<0·03). The expression of the hulless and waxy genes in barley is desirable for use in human food products due to increased levels of soluble dietary fibre, particularly beta-glucans, but reduces malting potential and feed value for poultry.