A new perspective on the concept of stability in common winter wheat (Triticum aestivum L.) and an indirect approach for integrating genotypic contrast

This study presents a novel concept for stability and adaptability in common winter wheat (Triticum aestivum L.), based on a quantitative assessment of the contrast between genotypes. In classical models, stability is often considered within the framework of either dynamic or static concepts, but without accounting for the actual genetic and phenotypic diversity present in the tested populations. The newly developed model integrates this aspect through functional modeling of the relationship between productivity and stability, utilizing a rotated biplot and indirectly integrating genotype contrast through functional modeling in the final evaluation. The model was applied to data from 13 newly developed lines and three standard cultivars, grown under highly contrasting agroecological conditions over three consecutive years. Analyses indicate that the model provides a more objective and precise ranking of the lines, enabling the simultaneous identification of high-yielding and stable genotypes, as well as those with broad or narrow adaptability. The results show a high correlation between the new parameters and classical models, confirming the scientific and practical adequacy of the proposed system. The integration of contrast eliminates distortions caused by extremely divergent genotypes and facilitates the selection of lines with balanced characteristics for practical breeding under variable conditions. The new model is characterized by universality and high efficiency in the comprehensive assessment of wheat genotypes.