Identifying Salt-Tolerant Durum Wheat Varieties (Triticum durum Desf.) Through Comprehensive Stress Analysis

High salinity levels significantly impede plant growth and yield, making it a pressing issue for wheat cultivation. Identifying accurate indicators of salt tolerance is essential for developing wheat cultivars that can thrive in saline conditions. To characterize the morpho-physiological, biochemical, and ionic responses of wheat to salt stress, we evaluated a diverse set of four wheat (Triticum durum Desf.) varieties (Simeto, Vitron, Oued el Bared, and Mansoura) at the tillering stage. The plants were grown in Hoagland’s solution supplemented with increasing concentrations of NaCl (50, 100, and 150 mM). Oued el Bared exhibited greater shoot and total fresh weight ratios, while Mansoura had higher root fresh weight ratios at 150 mM NaCl. Mansoura and Simeto suffered significant biomass reduction. Oued el Bared and Vitron retained higher leaf relative water content at 150 mM NaCl compared to Mansoura and Simeto. Proline levels increased in Vitron, Mansoura, and Simeto but decreased in Oued el Bared. Salt-sensitive varieties (Mansoura and Simeto) showed greater total chlorophyll synthesis, while Oued el Bared maintained higher chlorophyll b levels. Mansoura had higher sodium levels than Oued el Bared, indicating greater susceptibility to salinity. We observed correlations between leaf and root Na+ content, chlorophyll content, relative water content, root K+ and K+/Na+ ratios. Based on the salt tolerance index, Oued el Bared was the most tolerant variety, followed by Vitron, Simeto, and Mansoura. Each variety displayed unique adaptations to salt stress, highlighting the diversity of salt tolerance strategies in these plants.