Glutenin subunit compositions and breadmaking quality characteristics of synthetic hexaploid wheats derived from Triticum turgidum × Triticum tauschii (coss.) Schmal Crosses uri icon

abstract

  • The Glu-B1, Glu-D1 and Glu-B3 encoded glutenin subunit compositions of a population of synthetic hexaploid wheats (AABBDD, 2n=6x=42), which was random for flour protein (FP), SDS-sedimentation (SDSS), Alveograph strength (W), the tenacity/extensibility (P/G) ratio and bread loaf volume (LV) were examined in this study. The synthetics were produced from various crosses involving several Triticum turgidum cultivars and Triticum tauschii (coss.) Schmal accessions. The Glu-A1 null allele as well as three Glu-B1 (subunits 7+8, 6+8 and 20), 13 Glu-D1 and two Glu-B3 (LMW-1 and LMW-2) allelic variants were present in the synthetic population. Thirty-six different glutenin subunit combinations, including the Glu-B1, Glu-D1 and Glu-B3 encoded alleles, were observed. The synthetic hexaploids showed large variations for all quality parameters evaluated. AU quality characteristics except one (P/G ratio, which showed no association with allelic variations at Glu-B3) were influenced by allelic variations at the Glu-B1 and Glu-B3 loci; subunits 6+8 and 7+8 showed significantly better quality effects than subunit 20. Low M(r) glutenin subunits LMW-1 and LMW-2 showed both negative and positive quality effects. The Glu-D1 locus of I: tauschii contributed various alleles not found in bread wheat. The influence of new Glu-D1 alleles on the bread-making quality characteristics of the synthetic wheats could not be established, partly because there was a limited frequency of some of the alleles in the population, and partly because some synthetics, having a common Glu-DI allele, showed quality differences associated with allelic variation at Glu-B1 and/or Glu-B3. Differential quality effects could be observed, however, among some Glu-DI alleles. Synthetics derived from a common durum wheat source showed better overall quality characteristics and bread loaf volume when they possessed subunits 5+12 or 1.5+10 than when they had any other Glu-D1 encoded glutenin subunit.

publication date

  • 1995
  • 1995