Genetic characterization of FODMAPs and ATIs in heritage and modern spring wheat

The fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) and amylase-trypsin inhibitors (ATIs) present in wheat flour can trigger irritable bowel syndrome (IBS) symptoms and intestinal inflammation. Lowering FODMAPs and ATIs concentrations in wheat flour could make the grain accessible to humans with IBS. This study evaluated a diverse panel of heritage and modern spring wheat lines for FODMAPs and ATIs concentrations and carried out a genome-wide association analysis. A moderately strong population structure was observed as the first two principal component axes explained 10.9% of the genotypic variation, and lines grouped into three clusters. Trait correlations within and across locations ranged from -0.33 to 0.87. Broad-sense heritabilities ranged from 0.30 to 0.67. Evaluation of 33 varieties released by the University of Minnesota between 1915 and 2020 revealed no significant changes over time in ATIs or FODMAPs concentrations. Association analysis resulted in detection of 38 quantitative trait loci (QTL) in 12 chromosomes and three of the 38 QTL were common between two traits in the St. Paul location. The QTL were of small to medium effect as the range of explained phenotypic variation was 4.9%-11.8%. There was no overlap among the QTL regions reported in this research compared with those reported from previously published studies. Genomic prediction models predicted the traits with low to moderate trait correlations that ranged from 0.13 to 0.34. Discovery of markers associated with FODMAPs and ATIs, in conjunction with a genome-wide selection strategy, could aid in selection of breeding lines with desirable concentrations of these compounds.