Boosting Salt‐Removal by <i>Casuarina glauca</i> Through Preconditioning: Implications for Land Degradation and Mitigation

ABSTRACT Soil salinization is a major global threat to agriculture and land health. Cultivating salt‐tolerant species like Casuarina glauca offers a promising, sustainable restoration strategy. While C. glauca is known for its salt tolerance, its phytodesalination ability and ion‐specific adaptation mechanisms remain underexplored. In this study, we assessed the phytodesalination potential of C. glauca saplings (both preconditioned and non‐preconditioned) cultivated in saline soils over a 12‐month period, with a specific focus on the role of preconditioning. Results showed that preconditioned plants performed noticeably better than non‐preconditioned ones, with enhanced biomass, improved soil physicochemical conditions, and greater uptake of sodium (Na + ) and chloride (Cl − ). Importantly, C. glauca exhibited a high bioconcentration factor (BCF) for both ions, with low Na + translocation (TF) and high Cl − translocation, reflecting a dual phytostabilisation–phytoextraction strategy. Remarkably, high levels of Cl − accumulation in shoots did not impair aerial biomass, suggesting efficient chloride compartmentalization and exceptional Cl − tolerance. These findings demonstrate that C. glauca can initiate plant‐mediated soil improvements under saline conditions, supporting its potential use during the early establishment phase of land rehabilitation strategies.