Mapping of β-glucan content and β-glucanase activity loci in barley grain and malt

Abstract

Genetic study of β-glucan content and β-glucanase activity has been facilitated by recent developments in quantitative trait loci (QTL) analysis. QTL for barley and malt β-glucan content and for green and finished malt β-glucanase activity were mapped using a 123-point molecular marker linkage map from the cross of Steptoe/Morex. Three QTL for barley β-glucan, 6 QTL for malt β-glucan, 3 QTL for β-glucanase in green malt and 5 QTL for β-glucanase in finished malt were detected by interval mapping procedures. The QTL with the largest effects on barley β-glucan, malt βglucan, green malt β-glucanase and finished malt βglucanase were identified on chromosomes 2,1,4 and 7, respectively. A genome map-based approach allows for dissection of relationships among barley and malt βglucan content, green and finished malt β-glucanase activity, and other malting quality parameters.

The Genetics and Transcriptional Profiles of the Cellulose Synthase-Like HvCslF Gene Family in Barley

“…3). In the same region of barley chromosome 1H, Han et al (1995) detected overlapping QTLs for (1,3;1,4)-b-D-glucan content in ungerminated barley grain (Fig. 3), for malt (1,3;1,4)-b-D-glucan content, and for malt (1,3;1,4)-b-D-glucan endohydrolase activity.…”

“…Four barley genes, namely HvCslF3, HvCslF4, HvCslF8, and HvCslF10, mapped at the same position as the RFLP marker abc468, which is in the centromeric region of chromosome 2H. This map position is syntenous with the position of the cluster of six OsCslF genes on rice chromosome 7 and falls within a chromosome region in which Han et al (1995) detected a QTL that accounted for about 19% of the variation in grain (1,3;1,4)-b-D-glucan content in a 'Steptoe' 3 'Morex' mapping population. No orthologs of the rice OsCslF1 and OsCslF2 genes, which are also found in the rice cluster on chromosome 7, were detected in barley ( Fig.…”

“…Molecular markers flanking a major QTL on chromosome 2H for (1,3;1,4)-b-D-glucan content in ungerminated barley grain (Han et al, 1995) were used to locate the syntenous region of the rice genome on chromosome 7, in which a cluster of six rice OsCslF genes within a 100-kb region became prime candidates for a role in (1,3;1,4)-b-D-glucan synthesis . We have now used gene-specific probes to screen a 'Clipper' 3 'Sahara' barley doubled haploid mapping population (Karakousis et al, 2003) and have placed the individual barley HvCslF genes on a genetic map (Fig.…”

“…The other major QTL for (1,3;1,4)-b-D-glucan content in barley grain identified by Han et al (1995) was located on chromosome 1H and accounted for about 15% of the variation in grain (1,3;1,4)-b-D-glucan content. In the 'Clipper' 3 'Sahara' population used here, the HvCslF9 gene mapped near the centromere of chromosome 1H (Fig.…”

“…6C). Because a major QTL for (1,3;1,4)-b-D-glucan content of barley grain has been reported close to the gene encoding (1,3;1,4)-b-D-glucan endohydrolase isoenzyme EI (Han et al, 1995), levels of transcripts for the corresponding gene, which is designated HvGlb1, were also monitored during endosperm development. A sharp peak in mRNA abundance for HvGlb1 was detected at 12 DAP in the variety 'Sloop', but lower levels were detected in the variety 'Himalaya' (Fig.…”