Elevated CO₂(eCO₂) may mitigate stress-induced damage to cotton (Gossypiumspp.) growth and development.However, understanding the early-stage responses of cotton to multiple abiotic stressors at eCO₂ levels has been limited. This study quantified the impacts of chilling (CS, 22/14°C, day/night temperature), heat (HS, 38/30°C), drought (DS, 50% irrigation of the control), and salt (SS, 8 dSm^–1) stresses on pigments, physiology, growth, and development of 14 upland cotton cultivars under ambient CO₂(aCO₂, 420 ppm; current) and eCO₂(700 ppm; future) levels during the vegetative stage. The eCO₂partially negated the effects of all stresses by improving one or more of the pigments, physiological, growth, and development traits, except CS. For instance, HS at aCO₂significantly increased stomatal conductance by 36% compared with non-stressed plants at aCO₂. However, HS at eCO₂significantly decreased stomatal conductance by 18% compared with HS at aCO₂.The first squaring was delayed by one day under SS at aCO₂but two days earlier under SS at eCO₂than non-stressed plants at aCO₂.Root and shoot dry mass and the total leaf area were significantly higher under all stresses, except for CS, at the eCO₂compared with similar stresses at theaCO₂. Most growth and development traits, including plant height, leaf area, and shoot dry mass, displayed a mirroring response pattern between aCO₂and eCO₂ under all environments except CS.Cultivars exhibited significant interaction with stressed environments. Further, results revealed differential sensitivity and adaptation potential of cultivars to stress environments at varying CO₂levels. This study highlights the need to consider eCO₂in designing breeding programs to develop stress-tolerant varieties for future cotton-growing environments.

maize  /  abiotic stress combination  /  photosynthetic capacity  /  stem development  /  yield