MAPPING OF BETA-GLUCAN CONTENT AND BETA-GLUCANASE ACTIVITY LOCI IN BARLEY-GRAIN AND MALT

Genetic study of beta-glucan content and beta-glucanase activity has b een facilitated by recent developments in quantitative trait loci (QTL ) analysis. QTL for barley and malt beta-glucan content and for green and finished malt beta-glucanase activity were mapped using a 123-poin t molecular marker linkage map from the cross of Steptoe/Morex. Three QTL for barley beta-glucan, 6 QTL for malt beta-glucan, 3 QTL for beta -glucanase in green malt and 5 QTL for beta-glucanase in finished malt were detected by interval mapping procedures. The QTL with the larges t effects on barley beta-glucan, malt beta-glucan, green malt beta-glu canase and finished malt beta-glucanase were identified on chromosomes 2, 1, 4 and 7, respectively. A genome map-based approach allows for d issection of relationships among barley and malt beta-glucan content, green and finished malt beta-glucanase activity, and other malting qua lity parameters.