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A hydroponic experiment was carried out utilizing four barley genotypes with differing salt tolerances to investigate the influence of salinity (NaCl) and cadmium (Cd) on the activities of antioxidant enzymes, sodium (Na) and Cd concentrations, and accumulation in plants. The activities of the two antioxidant enzymes, superoxide dismutase (SOD) and peroxidase (POD), were significantly increased when plants were exposed to both Na and Cd stresses for all genotypes, relative to the control. The increased enzymatic activity was more predominant with a prolonged time of stress exposure. The combined stress (NaCl+Cd) led to a further increase in POD activity, but had little effect on SOD activity. Two salt-tolerant genotypes, ‘Gebeina’ and ‘Zhou 1,’ showed a more rapid increase of POD and SOD activities than the two salt-sensitive genotypes, ‘Newgoutei’ and ‘Quzhou’ in response to the combined stress treatment. Additions of NaCl to the Cd-containing medium caused a significant reduction in both Cd concentration and accumulation. The extent of the reduction in Cd concentration was also dependent on genotypes. The salt-tolerant genotypes had lower Na concentrations than sensitive genotypes, and the effect of Cd stress on Na concentration and accumulation varied with genotypes. It may be concluded that a significant interaction exists between Na and Cd in their influence on antioxidant enzyme activity and the accumulation of each element in the plant. [ABSTRACT FROM AUTHOR]

The cultivar and environmental variations of β-glucan content and β-glucanase activity in grains and malt were investigated in 8 barley cultivars grown at 7 locations. On average, for all cultivars and locations, approximately 80% of β-glucan present in grains was degraded after malting, but there was great variation among both cultivars and locations. β-glucanase activity was much lower but detectable in grains, and it dramatically increased after malting. The cultivar and environmental variations of β-glucan content were much higher in malt than in grains, and malt β-glucan content was more dependent on malt β-glucanase activity than the original level of β-glucan in grains. The correlation analysis of β-glucan content, β-glucanase activity and four malt quality parameters (Kolbach index, diastatic power, viscosity and malt extract) showed that malt-glucan content was highly significantly correlated with all quality parameters, while the association between grain β-glucan content and these quality parameters was relatively weak. Malt β-glucan content was negatively and highly significantly correlated with malt β-glucanase activity, and positively and significantly correlated with grain β-glucan content. It was also found that there was a positive and significant correlation between grain and malt β-glucanase activity. [Copyright &y& Elsevier]

β-Amylase activities of barley cultivars collected from various areas of China, and as well as from Canada and Australia, were assayed. Meanwhile a multi-location trial was conducted to determine variation of β-amylase activity in eight barley cultivars and the relationship between β-amylase activity and protein content. For 56 cultivars in study, β-amylase activity ranged from 458 to 1024 U/g, with a mean of 738 U/g. There was significant variation in both β-amylase activity and protein content for eight barley cultivars grown in four locations. No significant correlation was found betweenβ-amylase activity and protein content surveyed in 56 cultivars. [Copyright &y& Elsevier]