Comparison of low- and high molecular-weight wheat glutenin allele effects on flour quality

Five crosses were made, using a set of New Zealand wheat cultivars, to measure the effect of glutenin allele differences on baking quality parameters. The alleles involved were: Glu-A1 (2*, 1 and n), Glu-D1 (5+10, 2+12), Glu-A3 (c, d and e), Glu-B3 (Sec-12, Sec-13, b and g), Glu-D3 (a and b). The allelic variation of F₃ individual plants was identified by SDS-PAGE, and plants with the same HMW-GS and LMW-GS patterns were grouped. Quality parameters were then measured on the grouped F₄ bulks. Quality parameters measured for this study were wholemeal flour protein content (WFP), grain hardness (HAR), SDS sedimentation volume (SED), Pelshenke time (PEL), mid-line peak value (MPV) and the mid-line peak time (MPT) of a mixograph. The results showed there were significant quality differences within most populations associated with the possession of a particular allele, reaching magnitudes of up to 42% for the range between populations. Most glutenin allelic comparisons showed significant differences for at least one of the resultant measured quality parameters. Allelic differences of Glu-A1 significantly influenced all characters except MPT, with the null allele apparently inferior; possession of 5+10 at Glu-D1 significantly increased Pelshenke time and SED volumes relative to allele 2+12; WFP, SED and MPV were significantly affected by the Glu-A3 alleles tested. Glu-B3 alleles significantly affected all characters except hardness and the Glu-D3 alleles tested significantly affected all characters other than hardness and SDS sedimentation volume.