Cultivar and environmental effects on (1→3,1→4)-β-D-glucan and protein content in malting barley

A low beta -glucan and protein content is desirable for malting barley. In China high beta -glucan content has been considered a major factor contributing to the inferior malting quality of local barleys. In this study 10 barley cultivars were planted in multi-location trials in the southern winter-barley zone to determine genotypic and environmental effects on beta -glucan and protein content. There were highly significant differences in both beta -glucan and protein content between the 10 barleys, the eight locations and the 2 planting years. The average beta -glucan content over the 2 years for the 10 cultivars in the eight locations ranged from 3.91% for Gangpi 1 to 4.95% for Xiumei 3, and from 3.76% for Hangzhou to 4.75% for Taian in eight locations. Correspondingly, the protein contents of the 10 cultivars ranged from 11.7% for Yanyin 1 to 12-52% for ZAU, and of the eight locations from 9.5% for Hangzhou to 14.69% for Taian. Environmental factors contributed the largest component of the variation in both beta -glucan and protein content. Five climatic factors, namely the total accumulated temperature, accumulated temperature to 25 degreesC and to 30 degreesC, precipitation and days with rain during seed development were included in a regression equation relating climatic factors and beta -glucan content. In the regression equation relating climatic factors and protein content, two other factors, days from heading to maturity and accumulated temperature to 20 degreesC were included, in addition to the five climatic factors that significantly affected beta -glucan content. (C) 2001 Academic Press.