• Coordinated physiological and metabolic responses drive broccoli salt resilience. • A conservative water-use strategy prevents salinity-induced dehydration in BQ1. • Leaf retention of phosphorous and boron supports cellular integrity under ionic stress. • Sucrose and maltose accumulation fuels energy metabolism for salt adaptation. • Early antioxidant induction mitigates oxidative damage during initial stress. Soil salinization represents a primary abiotic constraint to global agricultural pro