Effectiveness of an image-based sorter to select for kernel color within early segregating hard winter wheat (Triticum aestivum L.) Populations

This study evaluated the effectiveness of an image sorter to select for kernel color within early generations of segregating hard winter wheat populations. The wheat crosses originated from different combinations of white and red parents. Three generations (F3, F4 and F5) of sorting were applied to six segregating populations. At each generation, samples of whitesorted, red-sorted, and unsorted populations, along with the parents of the populations, were planted in replicated trials at multiple locations. The sorter processed 1kg sized samples in ~30 min and samples were sorted for 108 plots per season. ~10% of the F3 populations were sorted and planted as white-sort population. This resulted in minimal changes in the % of white kernels. ~3% of the F4 and F5 populations were sorted and planted as white-sorted populations and significant advancement occurred. The F6 populations of white-sorted samples from Dakota Lake ranged from 80% to 92% white kernels. The F6 populations from Brookings ranged from 53% to 83% white kernels. Sorting for red seed decreased the frequency of white seed as compared to the unsorted reference populations; however reductions, of white seeds in the red populations, were modest and required three cycles of selection for significant effect. The effectiveness of the image-sorter varied with population and environment and sorting methods

Quantitative trait locus analysis of wheat quality traits

Milling and baking quality traits in wheat (Triticum aestivum L.) were studied by QTL analysis in the ITMI population, a set of 114 recombinant inbred lines (RILs) generated from a synthetic-hexaploid (W7985) x bread-wheat (Opata 85) cross. Grain from RILs grown in U.S., French, and Mexican wheat-growing regions was assayed for kernel-texture traits, protein concentration and quality, and dough strength and mixing traits. Only kernel-texture traits showed similar genetic control in all environments, with Opata ha alleles at the hardness locus Ha on chromosome arm 5DS increasing grain hardness, alkaline water retention capacity, and flour yield. Dough strength was most strongly influenced by Opata alleles at 5DS loci near or identical to Ha. Grain protein concentration was associated not with high-molecular-weight glutenin loci but most consistently with the Gli-D2 gliadin locus on chromosome arm 6DS. In Mexican-grown material, a 2DS locus near photoperiod-sensitivity gene Ppd1 accounted for 25% of variation in protein, with the ppd1-coupled allele associated with higher (1.1%) protein concentration. Mixogram traits showed most influence from chromosomal regions containing gliadin or low-molecular-weight glutenin loci on chromosome arms 1AS, 1BS, and 6DS, with the synthetic hexaploid contributing favorable alleles. Some RI lines showed quality values consistently superior to those of the parental material, suggesting the potential of further evaluating new combinations of alleles from diploid and tetraploid relatives, especially alleles of known storage proteins, for improvement of quality traits in wheat cultivars