Chromium (Cr) contamination in agricultural soils poses a significant risk to food safety and crop productivity, particularly in rice (Oryza sativa L.), a staple food crop. Phyto-stabilization assisted with biochar application could be a potential solution for mitigation of Cr accumulation in grain. Rice husk is a potential byproduct for biochar preparation. This study investigated the impact of rice husk biochar application on the accumulation of Cr in rice grown in contaminated soils. A pot experiment was conducted using rice plants grown in soils spiked with varying concentrations of Cr (0, 25, 50, 75, 100 ppm) each under four rice husk biochar treatments (0, 20, 40, 60 t ha-1) respectively. Cr levels in soil and plant tissues were measured using atomic absorption spectrophotometer, quality parameters were analyzed along with enrichment and translocation factors. Results indicated the synchrony of Cr accumulation in grain and straw as per high Cr treatment in soil. A substantial reduction in Cr uptake was noticed in plants under treatments with biochar as an amendment, which demonstrated biochar's ability to immobilize Cr in the soil. Application of biochar best reduced Cr uptake (0.68 μg g-1 in shoot and 0.86 μg g-1 in root) in the treatment where Cr was not spiked, and biochar was applied @60 t ha-1. This study highlights the practical use of rice husk biochar as a sustainable amendment for mitigating Cr accumulation in rice, thus enhancing food safety and crop resilience in contaminated areas.
