Variability of the mineral composition of durum wheat grain (Triticum durum Desf.) under different environmental conditions

The composition of wheat grain plays a key role in determining its nutritional value. In this work, a collection of 133 durum wheat varieties and breeding lines was assessed for the content of macroelements (Ca, Mg, K), microelements (Cu, Mn, Zn, Fe, Na) and toxic metals (Pb, Cd, and Cr) in grain under the environmental conditions of Samara and Novosibirsk regions in 2023. The results showed a wide range of variations in the concentration of all elements depending on genotypic differences between the samples as well as the growing region. Ca and Mg contents in the varieties grown in Samara region showed a significant excess of 3.1- and 1.5-fold, respectively. Zn, Pb, and Cr content in the varieties cultivated in Novosibirsk turned out to be two times as high. Statistical analysis of element concentrations in the varieties of different origin indicates that Russian breeding lines significantly outperform Russian cultivars in Mg content, while being inferior in K, Cu, and Mn. Compared to Russian cultivars and breeding lines, foreign varieties demonstrated higher contents of K and heavy metals Cd and Cr. Correlation analysis using mean values of indicators for two environments showed highly significant ( p < 0.001) positive relationships between the content of microelements Fe/Mn (r2 = 0.69), Fe/Zn (r2 = 0.49), and Zn/Mn (r2 = 0.46), which suggests a feasibility of selecting genotypes for several elements at once. Multivariate statistics divided the durum wheat collection into two groups, one of them including Russian cultivars and breeding lines as well as some foreign genotypes. A separate cluster included seven Russian breeding lines placed at a distance from the other varieties, which suggested their potential differences at the genetic level. Comparing these lines with respect to mineral composition showed that they were, on average, characterized by higher Mg, K, Zn, and Fe contents. The data obtained in this study can be used for genetic research and breeding to improve the grain mineral composition of the modern durum wheat varieties.