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

Introduction: The aims of the present study are to investigate the effects of Ce on the growth and some antioxidant metabolisms in rice seedlings ( Oryza sativa L. cv Shengdao 16). Materials and methods: The rice was treated with 0, 0.05, 0.1, 0.5, 1.0, and 1.5 mM Ce, respectively. The growth index of rice was measured. The chlorophyll content; catalase, superoxide dismutase, and peroxidase activities; and the level of hydrogen peroxide (HO), superoxide anion (O), and malondialdehyde were assayed. The accumulation of Ce and the uptake of mineral nutrition elements were analyzed with ICP-SF-MS. Results and discussion: Hormetic effects of Ce 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 Ce than shoots and Ce 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 Ce treatments, which indicated that Ce affected the nutritional status of roots and shoots and further affected the growth of rice. Conclusion: The appropriate amount of Ce improved the defense system and growth of rice. The roots can accumulate a much higher content of Ce 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 Ce treatments. [ABSTRACT FROM AUTHOR]