NaCl-induced soil salinity constrains crop productivity by disrupting ionic balance, inducing osmotic stress, and promoting excessive reactive oxygen species (ROS) generation that damages cellular structures. Salicylic acid (SA) is a key stress-signaling molecule known to enhance antioxidant regulation and cellular homeostasis. This study evaluated the morpho-anatomical and biochemical responses of Spinacia oleracea L. to salinity stress and assessed the mitigating potential of foliar-applied SA. Plants were exposed to four NaCl levels (50, 100, 150, and 200 mM) applied via irrigation, either alone or combined with foliar SA at 0.5 and 2.5 mM for three weeks. Salinity markedly reduced growth attributes (biomass, shoot and root length, plant height) and disrupted anatomical organization (epidermal thickness, cortex cell area, vascular region area, and stem cross-sectional area) relative to controls, alongside biochemical disturbances associated with oxidative stress. Foliar SA application (1.5 mM) substantially alleviated these effects, preserving structural integrity and improving stress tolerance compared with plants exposed to NaCl alone. These findings demonstrate that exogenous foliar SA application mitigates NaCl-induced morpho-anatomical and biochemical damage in spinach by supporting structural stability and physiological resilience under saline conditions.
Taseer et al. (Fri,) studied this question.