Heritabilities of small-scale and standard measures of wheat quality for early generation selection

Abstract

This paper compares offspring-parent heritability estimates for a number of small-scale early generation quality tests with those from standard macromeasures of wheat quality for their application to early generation selection for wheat quality. It especially reports heritability estimates for two new small-scale tests, the proportion of total flour protein insoluble in dilute acetic acid (residue protein) and the sodium dodecyl sulfate sedimentation volume. Materials utilized in this study were 21 random F3 lines and their derived F4 bulks from each of seven wheat crosses.The heritability estimates for the determination of quality by small-scale and standard macro-quality test procedures varied between crosses, and the lack or range in test values in either generation was generally not the cause of the low to zero estimates obtained.Flour milling yield and flour protein content were the only two small-scale tests to exhibit low to zero heritability estimates in some crosses, while for the standard macromeasures it was the farinograph properties, development time and dough breakdown, and the extensograph properties, extensibility and resistance to stretching.When data were pooled over crosses, medium to high heritability estimates were obtained for all of the small-scale test procedures and for all of the macromeasures except for farinograph development time and dough breakdown and extensograph extensibility.Despite the effects of genotype x environment interactions in reducing heritability, the estimates reported indicate that, where seed quantity is limiting, good average response to early generation selection can be expected using tests to estimate grain hardness, flour protein content and a measure of protein quality. When seed quantity is not limiting, good average response to early generation selection can be expected using the standard macromeasures of wheat quality.