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Salinity and alkalinity stresses are common in arid and semiarid climates. Both these stresses not only retard crop growth but also cause a severe reduction in yields. The present experiment was performed to investigate the morphological, physiological, biochemical, and genetic responses of two maize hybrids (FH-1231 and DK-6714) to salinity and alkalinity stresses. The treatments were comprised of salt stress (NaCl:Na₂SO₄ at a 9:1 ratio), alkaline stress (NaHCO₃:Na₂CO₃ at a 9:1 ratio), and an unstressed control. The results indicated that salinity and alkalinity significantly reduced shoot fresh weight by 50% and 70%, root fresh weight by 38% and 50%, root dry weight by 69% and 93%, seedling length by 18% and 30%, number of leaves by 27% and 39%, and maximum leaf width by 17% and 24%, respectively, across the two hybrids compared with control, indicating that alkalinity had a greater effect than salinity. Likewise, both the stresses, particularly alkalinity, significantly decreased K⁺ ion accumulation and chlorophyll content and increased the lipid peroxidation rate, sodium (Na⁺) concentration, the hydrogen peroxide (H₂O₂) level, and the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX). Salinity and alkalinity stresses also induced the expression levels of antioxidant genes (<i>SOD</i>, <i>CAT</i>, <i>POD</i>, <i>APX</i>); however, salinity showed less effect than alkalinity stress. Similarly, hybrid DK-6714 performed comparatively better than FH-1231 with regard to seedling growth, antioxidant activities, and biochemical attributes under stress conditions. Thus, DK-6714 is recommended as a suitable hybrid for soils affected with salt-alkalization.