Fe-Mn impregnated biochar alleviates di-(2-ethylhexyl) phthalate stress in vegetative growth of wheat

In this study, we examined the effects of 0.5–2% iron and manganese oxide-modified biochar (FM) as remediation to control di-(2-ethylhexyl) phthalate (DEHP) in the soil and the response of wheat at different growth stages. The application of FM and original biochar (BC) significantly reduced DEHP concentrations in wheat roots and leaves and effectively immobilised DEHP in soils at different stages, and alleviated the oxidative damage of DEHP by significantly reducing O2– and H2O2 content and increasing the activities of antioxidant enzymes, including superoxide dismutase, catalase, and ascorbate peroxidase. Moreover, photosynthetic parameters (stomatal conductance, intercellular carbon dioxide concentration, photosynthetic rate, and transpiration rate) and fluorescence indicators (maximum photochemical efficiency, electron transport rate, and actual quantum yield) of the wheat growing in DEHP-spiked soils were also improved, which caused increases in the biomass of above-ground and underground at the seedling, booting, and ripening stages. Compared to BC, the FM amendment led to a greater improvement in crop biomass by reducing DEHP bioavailability. Therefore, FM has a good potential for the remediation of DEHP-polluted soils.