Variation in type and relative amounts of the high molecular weight glutenin subunits in dutch wheat varieties

Abstract

Abstract:The high molecular weight glutenin (HMWg) subunit genotypes and amounts of the individual subunits of 38 Dutch wheat varieties were determined. In winter wheat varieties, HMWg subunit alleles that, in general, have been shown to be related to a poor bread-making quality predominated. In spring wheat varieties, ' high-quality ' alleles were most frequent. When examining the published HMWg subunit genotypes of British and German varieties a similar difference was found in HMWg subunit genotype between spring and winter wheats. Because bread-making quality of spring wheat varieties is, in general, superior to that of winter wheats, probably also because of the lower protein content of the latter, the two groups should be taken separately when studying the relation between HMWg subunit genotype and bread-making quality. There was a considerable variation in relative amounts of allelic HMWg subunits and of subunits encoded by different genes (at the same or homeologous loci). Between varieties with the same HMWg subunit genotype, relative amounts of identical subunits differed only slightly. Some of these differences may reflect differences in gene expression, but it is not known to what extent differences in genetic background or differences in gene promoter are involved. There were differences in relative amounts of HMWg subunits encoded by alleles at the Glu-B1 locus. Here, an increase in relative amounts coincided with an increase in contribution to bread-making quality of an allele.

Perspectives to breed for improved baking quality wheat varieties adapted to organic growing conditions

“…Payne and co‐workers21 claimed that about 50% of the variation for baking quality could be explained by this scoring system. Subsequent studies of different groups showed that not all gene effects were additive, also epistatic effects occurred (see e.g Refs 29 and 30), and that the amount of variation explained by the HMWGS depends on the genetic background of the material tested. Kolster et al ,30 for example, estimated that only 20% of the variation for loaf volume could be explained in a set of winter wheat lines of a Dutch breeding programme.…”

Characterization of a Monoclonal Antibody Specific for HMW Subunits of Glutenin and Its Use To Investigate Glutenin Polymers

“…There is evidence that interchain disulfide bonds between HMW subunits are not random (Shewry and Tatham, 1997) and it has been suggested that an extra cysteine residue present in the repetitive domain of 1Dx5 is responsible, in part at least, for the quality associated with subunits 1Dx5 + 1Dy10, when compared with subunits 1Dx2 + 1Dy12. In addition, it is probable that the quantity of HMW subunits present in a variety of wheat is also important in determining gluten viscoelasticity (Halford et al, 1992;Kolster et al, 1993;Sutton, 1991). Such an effect may account for the increased quality associated with the expression of a 1Ax subunit (Halford et al, 1992).…”