Аңдатпа
This study was conducted to evaluate the duration of the main phenological phases in spring soft wheat (Triticum aestivum L.) accessions belonging to different maturity groups and to determine their contribution to grain yield formation in the dry steppe zone of northern Kazakhstan. The research was conducted in 2021-2023 at the A.I. Barayev Scientific and Production Center for Grain Farming using a collection of 99 spring soft wheat accessions of various ecological and geographical origins. The accessions were divided into early-ripening, mid-season, and mid-late groups depending on the duration of the growing season. Phenological observations included recording the dates of germination, heading, and wax ripeness. Data were processed using analysis of variance (ANOVA), Tukey’s multiple comparison test (HSD), and Pearson’s correlation analysis. The results of studies between maturity groups for the duration of the overall growing season and the “seedling-to-heading” period were statistically significant, while the duration of the “heading-to-wax ripeness” period and average grain yield did not differ statistically significantly. The increase in the overall growing season was primarily due to an extension of the “seedling-to-heading” period. A positive correlation between the duration of the “seedling-to-heading” period and grain yield was established for early- and mid-late-ripening varieties. No statistically significant relationships were found in the mid-ripening group. Graphical analysis revealed the following varieties: Tyumenskaya 27, Zauralskaya Volna, Niva Priirtyshya, Start, L.654, and Stepnodar 90, which combine favorable phenological characteristics with high yield. The study results indicate that the germination-to-heading period is the main phenological component determining differences between maturity groups and can be considered an important breeding trait for increasing the adaptability and yield stability of spring soft wheat in northern Kazakhstan.