This study sought to assess the yield performance, ecological stability, and physiological traits of 10 winter wheat (Triticum aestivum L.) genotypes grown for three years (2023–2025) under variable agroclimatic conditions of the Khorezm Region, Uzbekistan. Field trials conducted had a randomized complete block design with three replications. Yield stability evaluation used the coefficient of variation (CV), while physiological adaptation determination employed the chlorophyll content (soil plant analysis development, or SPAD). Significant genotypic differences observed were prevalent in yield and physiological responses, especially under early heat stress in 2025. The highest mean grain yields resulted in cultivars Sila (572.5 g m⁻²) and Nikifor/Kroshka (543.0 g m⁻²). Among these, the genotype Sila showed the lowest CV (0.84%), indicating the utmost ecological stability and broad adaptability. Both wheat genotypes also maintained the maximum SPAD values (> 58.5), reflecting robust photosynthetic tolerance in stress conditions. However, regression analysis revealed a weak relationship between chlorophyll content and grain yield, indicating high SPAD alone does not ensure yield superiority. Overall, the genotype Sila succeeded in its identification as an optimal genotype, combining high yield and stability, while the genotype Nikifor/Kroshka appeared suitable for favorable environments. The results support breeding strategies aimed at improving the yield stability under varied climatic conditions.

Keywords: Wheat (T. aestivum L.), yield, ecological stability, coefficient of variation, stress, SPAD, genotype-environment interaction

Key findings: Wheat (T. aestivum L.) cultivars Sila (572.5 g m⁻²) and Nikifor/Kroshka (543.0 g m⁻²) recorded the highest average grain yield. The cultivar Sila showed the lowest coefficient of variation, confirming its better ecological stability. Both genotypes maintained the highest SPAD values in stress conditions, revealing robust photosynthetic tolerance.