Wheat–alien introgression lines: an underutilised source of variation for micronutrient enrichment, grain functionality and cadmium accumulation

Key message Disease-resistance-derived wheat–alien introgression germplasm showed multidimensional grain-quality variation and exploratory genomic associations warranting validation for pre-breeding. Abstract Micronutrient malnutrition increases the need for wheat germplasm combining improved nutritional quality, food safety and protein-related grain-quality characteristics. Disease-resistance-derived wheat–alien introgression germplasm may provide underutilised variation for these traits. A panel of 153 genotypes comprising wheat–alien introgression lines, triticale and modern wheat cultivars was evaluated for grain iron (Fe), zinc (Zn), cadmium (Cd), an SE-HPLC-derived protein-content proxy, percentage of unextractable polymeric protein (%UPP), and soluble and bound polyphenols under a single-year, single-location field experiment. All evaluated traits differed among the 28 chromosome-constitution classes. Selected classes exhibited comparatively high Fe and Zn concentrations with lower Cd accumulation, whereas others showed favourable protein-content-proxy, %UPP or polyphenol profiles. Fe, Zn and the protein-content proxy were positively correlated ( r = 0.40–0.65), whereas Cd showed weak associations with Fe and Zn. Multi-genotype classes including 2R/2D, 3R/3D and 2R/2B showed favourable combinations of nutritional, protein-related and food-safety traits, although class effects could not be separated from differences in wheat genetic background. Exploratory GWAS identified 33 Bonferroni-significant SNP–trait associations across the wheat- and rye-genome datasets, including 13 associations detected by both BLINK and FarmCPU. Several wheat associations occurred on chromosomes implicated in similar grain-quality traits, while rye associations occurred on 1R, 2R, 3R, 4R, 5R and 7R. These associations represent candidate genomic regions requiring validation across environments and independent genetic populations. The results indicate that disease-resistance-derived wheat–alien introgression germplasm contains multidimensional grain-quality variation warranting further pre-breeding evaluation, although the stability and genetic basis of the observed profiles remain to be established.