Effects of Lanthaum on Active Oxygen Metaboism in Soybean

Abstract

With many natural and anthropogenic factors, rare earth (RE) compounds in the environment are increasing. It affects not only plant growth but also ecosystem. So an experiment was conducted to investigate the effects of elevating rare earth element La concentration singly treatments [La-0(CK), La-50(50mg·L-1), La-100(100 mg·L-1) and La-150(150 mg·L-1)] on the changes of lipid peroxidation extent,ROS production rate,content and anti-oxidative enzymes activities in soybean (Glycine max) roots. The results showed that during the whole growth stage the elevated La concentration at 100mg·L-1 induced a decrease on the content of malondialdehyde (MDA),superoxide anion (O2) production rate,hydrogen peroxide (H2O2) content, which were lower than the other treatments, however, an increase on the activities of superoxide dismutase (SOD),catalase (CAT),peroxidase (POD),which were higher than the elevated La concentration at 50mg·L-1, 150mg·L-1 and CK. The results demonstrated that with the increase of La concentration, metabolism rates of reactive oxygen species (ROS) are restrained with the protective ability of anti-oxidative system strengthened. However, when the La concentration is higher than some concentration which is around 100 mg·L-1, the activities of anti-oxidative enzymes drop and reactive oxygen species accumulate, thus increasing membrane lipid peroxidation, which represents injured effects on soybean.