LAUSR

In the current study, the effect of trivalent cerium (Ce3+) on the production of reactive oxygen species (ROS) was investigated in the root of Arabidopsis thaliana by an in vitro study. The roots of A. thaliana were exposed with 0, 1, and 5 μmol/L Ce3+ for 12 h in vitro. It was found that the level of H2O2, O2.−, and ·OH was enhanced by 5 μmol/L Ce3+, but reduced by 1 μmol/L Ce3+. The activities of peroxidase (POD), catalase (CAT), and superoxidase dismutase (SOD) were enhanced by 1 μmol/L Ce3+, but reduced by 5 μmol/L Ce3+. Moreover, we used a laser‐scanning confocal microscopy to detect the changes of ROS in the root cells of A. thaliana by using a fluorochrome 2′,7′‐dichlorofluorescein diacetate (H2DCF‐DA). It showed that the level of ROS was declined in the root cells treated by 1 μmol/L Ce3+, but the oscillation of ROS was found in the root cells treated with 5 μmol/L Ce3+. In addition, REEs affect the uptake of mineral elements, which may be related to the oxidative stress in the cells of roots. In all, the data of our study indicated that the appropriate concentration of Ce3+ exhibited an anti‐oxidation property and improved the defense system in the root cells of A. thaliana.