Environmental constraints on the efficiency of selection for malting quality in barley

A range of screening tests has been applied to samples of barley from breeders' trials to evaluate the usefulness of rapid tests. The prediction of the malting potential of genotypes over seasons was best achieved by the use of hot water extract measurements. Environmental effects can result in a poor relationship between hot water extract and grain characters such as β-glucan content and thousand corn weight. Hot water extract varied considerably over sites, but results relative to a control cultivar were consistent provided that trials in which material malted poorly were eliminated from the comparisons.