Effect of saline irrigation on Tetragonia tetragonioides (Pall.) Kuntze grown on different soil types under greenhouse conditions

BACKGROUND Climate change and population growth are major challenges for sustainable food production, particularly in regions affected by water scarcity and soil salinization. In this context, halophytes represent promising candidates as alternative and sustainable food crops for salt-affected areas. RESULTS The results of an experiment evaluating the salt responses and nutritional values of the edible halophyte Tetragonia tetragonioides grown at three salinity levels (0, 100, and 200 mmol L−1 NaCl) in two soils with different textures revealed similar growth parameters under control and 100 mmol L−1 NaCl conditions in both soils. Conversely, the 200 mmol L−1 NaCl treatment negatively affected plant growth, with plants grown in Soil A + S consistently outperforming those grown in Soil A. At moderate salinity (100 mmol L−1 NaCl), water productivity increased, driven by lower stomatal conductance and transpiration rates. Moreover, mineral analysis of edible leaves revealed a progressive accumulation of Na and Cl with increasing salinity, especially in Soil A-grown plants. On the other hand, salt-grown plants had higher leaf Cu, Zn and Mn concentrations, key micronutrients often lacking in human diets. Furthermore, soils sampled near plant roots showed lower electrical conductivity (EC) compared to distant soil samples, confirming a phytodesalination effect by T. tetragonioides. CONCLUSION The obtained results indicate that T. tetragonioides can be successfully cultivated in moderately saline soils (EC < 20 dS m−1), providing dual benefits: production of mineral-enriched edible biomass and partial remediation of salt-affected soils. This dual role highlights its potential as a valuable crop for sustainable agriculture in marginal saline environments.