Effect of lead on oxidative status, antioxidative response and metal accumulation in Coronopus didymus

A screenhouse experiment was conducted to assay the effect of Lead (Pb) on oxidative status, antioxidative response and metal accumulation in Coronopus didymus after 6 weeks. Results revealed a good Pb tolerance and accumulation potential of C. didymus towards the increasing Pb concentrations (500, 900, 1800, 2900 mg kg−1) in soil. The content of Pb in roots and shoots elevated with higher Pb levels and reached a maximum of 3684.3 mg kg−1 and 862.8 mg kg−1 Pb dry weight, respectively, at 2900 mg kg−1 treatment. Pb exposure stimulated electrolyte leakage, H2O2 level, MDA content and the activities of antioxidant machinery (SOD, CAT, APX, GPX and GR). However, at the highest Pb concentration, the activities of SOD and CAT declined. The H2O2 level and MDA content in roots increased significantly up to ∼500% and 213%, respectively, over the control, at 2900 mg kg−1 Pb treatment. Likewise, concurrent findings were noticed in shoots of C. didymus, with the increasing Pb concentration. The present work suggests that C. didymus exhibited a good accumulation potential for Pb and can tolerate Pb-induced oxidative stress by an effective antioxidant defense mechanism. [Display omitted] •Coronopus didymus flourished well in Pb-enriched soil, up to the range of 1800 mg kg−1, without showing any visible toxic symptoms.•C. didymus accumulated Pb more in roots than shoots.•Pb-induced oxidative stress was higher in roots compared to shoots.•Antioxidative response diminished ROS and induced tolerance mechanism in C. didymus to overcome oxidative stress.•C. didymus can be used to remediate Pb-contaminated soils due to effective antioxidative mechanism.