Cultivar and Environmental Effects on β-glucanase Activity in Both Barley Grain and Malt and Its Function in β-glucan Degradation

摘要

Eight two-rowed barley cultivars were grown at seven locations in the southern winter-barleyzone of China. Mean grain β-glucanase activity ranged from 39.89 U kg-1 for Suyin2 to 49.75 U kg-1 for Xi-umai3 in 8 cultivars grown at 7 locations, and from 38.74 U kg-1 in Zhengzhou to 57. 96 U kg-1 in Putianamong 7 locations on an average of all cultivars. Correspondingly, mean malt β-glucanase activity of 8 culti-vars ranged from 313.33 U kg-1 for ZAU3 to 489.89 U kg-1 for Daner Barley, and of 7 locations from 330.40U kg-1 in Yancheng to 418.24 U kg-1 in Putian. There were significant differences among cultivars and loca-tions in malt β-glucanase activities. The locations showed much larger variation in malt β-glucanase activitiesthan cultivars. The reduction of total β-glucan content after malting varied in both cultivars and locations,with a mean of 78.31%. The analysis of correlations showed that malt β-glucan content was significantly posi-tively and negatively correlated with grain β-glucan content and malt β-glucanase activity, respectively, andmalt β-glucanase activity was significantly positively correlated with grain β-glucanase activity.