Genetic variability of bread wheat (Triticum aestivum L.) genotypes under drought conditions targeting the CWANA region

Drought stress limits grain yield in bread wheat, challenging agricultural productivity in regions like Morocco, where yields are below global standards. A gap in stable drought-tolerant varieties remains, requiring further research. This study evaluates 200 bread wheat genotypes under rain-fed and irrigated conditions (2020–2021) to identify candidates with improved drought tolerance. The research measured eight traits and used PCA, HCA, ANOVA, and Pearson correlation to identify key traits for drought tolerance, group similar genotypes, assess significant differences, and evaluate trait relationships. The results showed significant variation, with genotypes G150 and G57 yielding 4.03 t/ha and 4.0 t/ha, respectively, outperforming the average yield of 2.5 t/ha under drought stress. Notably, the days to heading at the Merchouch station (rainfed) exhibited the lowest coefficient of variation (CV) at 3.2 %, while the days to maturity at the Sidi Al-Aidi station (irrigated) showed the lowest CV at 2.5 %. The analysis revealed significant genotype-by-environment (G x E) interactions, underscoring the importance of selecting genotypes suitable for specific environmental conditions. Genotypes such as G150 and G57 demonstrated superior performance under drought stress, while others excelled in non-stress conditions. PCA identified key traits contributing to drought tolerance, including grain yield, biomass, and days to heading (r = 0.48), which were positively correlated with yield potential. Grain yield, a critical agronomic trait, showed moderate heritability, indicating both genetic and environmental influences. Identifying drought-tolerant genotypes offers valuable material for breeding programs to improve drought resilience and yield stability in the CWANA region, supporting food security amid changing climates.