The effects of cerium on the growth and some antioxidant metabolisms in rice seedlings

The aims of the present study are to investigate the effects of Ce3+ on the growth and some antioxidant metabolisms in rice seedlings (Oryza sativa L. cv Shengdao 16). The rice was treated with 0, 0.05, 0.1, 0.5, 1.0, and 1.5 mM Ce3+, respectively. The growth index of rice was measured. The chlorophyll content; catalase, superoxide dismutase, and peroxidase activities; and the level of hydrogen peroxide (H2O2), superoxide anion (O (2) (center dot-) ), and malondialdehyde were assayed. The accumulation of Ce3+ and the uptake of mineral nutrition elements were analyzed with ICP-SF-MS. Hormetic effects of Ce3+ on the growth and some antioxidant metabolisms were found in the roots and shoots of rice. The roots can accumulate a much higher content of Ce3+ than shoots and Ce3+ mainly located in the cell wall of roots. Moreover, the uptake of K, Mg, Ca, Na, Fe, Mn, Zn, Cu, and Mo in the roots and shoots was affected with the exposure of different Ce3+ treatments, which indicated that Ce3+ affected the nutritional status of roots and shoots and further affected the growth of rice. The appropriate amount of Ce3+ improved the defense system and growth of rice. The roots can accumulate a much higher content of Ce3+ than shoots. Moreover, the uptake of K, Mg, Ca, Na, Fe, Mn, Zn, Cu, and Mo in the roots and shoots was affected with the exposure of different Ce3+ treatments.