Fast-germinating low β-glucan mutants induced in barley with improved malting quality and yield.

Mutation breeding has been used to improve the speed of germination in the high-yielding spring barley variety Troubadour. Five mutants were selected which combined fast germination and good agronomic performance. Two of these mutants yielded significantly more than did Troubadour over eight environments, and showed a clear improvement in their malting quality through an increase in extract yield. The improvement in malting quality appeared to be due to a decrease in the β-glucan content, which seemed to enhance the germination speed and thus the starch degradation. The improvement in grain yield is postulated to be due to a better early growth caused by the enhanced germination speed. All the described changes could theoretically be explained by a single mutation event in each of the mutant genotypes, affecting the quantity of β-glucans present in the endosperm.