Genetical investigations into β-glucan content in barley.

Random inbred lines produced by doubled haploidy (DH) and single seed descent (SSD) have been used to investigate the genetics of β-glucan (gum) content in barley (Hordeum vulgare). Genetical analyses indicated that gum content is controlled by a simple additive genetic system. Significant negative genetic correlations were observed between β-glucan content, thousand grain weight and height in the DH samples. These correlations were much reduced in the SSD samples and would suggest linkage of the genes controlling these characters. The presence of repulsion linkages could be exploited in a barley breeding programme by producing F1 derived DH to generate recombinants with high thousand grain weight and low β-glucan content. Genetical parameters estimated from DH and F3 samples have successfully been used to predict the number of inbred lines transgressing the parental range for β-glucan content and bivariate combinations involving β-glucan.