Bioavailability of cd and pb to indian mustard (Brassica juncea (L.) Czern.) as influenced by Biochar

Abstract

Contamination of soils with cadmium (Cd) and lead (Pb) poses serious threat to the environment as well as human health via their entry in the food web. Exploration of the viable remedial measures has become inevitable to prevent their entry into the food chain. Thus, the present screen house study was undertaken to evaluate the effect of rice residue biochar on bioavailability to Indian mustard (Brassica juncea (L.) Czern) in a loamy sand soil spiked with four levels of Cd and Pb varying from 0 to 40 mg kg−1 and 0 to 200 mg kg−1 soil, respectively. The soil of the metal treated pots was further amended with four rates (0, 1%, 2% and 4%, w/w) of rice residue biochar. Crop was grown for 60 days with recommended doses of nitrogen and phosphorus. Addition of biochar up to 2% increased the above ground biomass of Indian mustard but decreased with application @ 4% as compared to unamended soil. Application of biochar significantly reduced the accumulation of Cd and Pb by the crop with increasing rates of its application. The ameliorative efficiency of biochar for Pb was more as compared to Cd. It was concluded that rice residue biochar has the potential to curtail the solubility, availability and translocation of Pb and Cd to Indian mustard.