Relationships between barley hordeins and malting quality in a mutant of cv. triumph I. Genotype by environment interaction of hordein content

The genetic (G), environmental (E) and G x E effects on total grain protein and hordein fractions, have been Studied in a mutant (TL43) and its parent cultivar, the malting barley. Triumph, in various seasons at Dundee (E Sco tland) and Lleida (NE Spain). The grain protein content of TL43 was consist ently about 2% higher than that of Triumph across environments. Differences in hordein composition were shown by SDS-PAGE electrophoresis. TL-43 had t hree B-hordein bands not present in Triumph which had a Further three bands of the same hordein group not present in TL43. TL43 showed higher B-hordei n content than Triumph in Scotland but lower in Spain, whereas the mutant s howed consistently higher C- and D-hordein content than Triumph across envi ronments, i.e. there was crossover G x E interaction for B-hordein and non- crossover for C- and D-hordein content. There were also differences in grai n ultra-structure between the two lines, as TL43 showed a more dense protei n matrix than Triumph, together with thinner pericarp, testa and aleurone l ayers. It was concluded that the mutation in TL43 had a significant effect on storage protein composition. (C) 2001 Academic Press.