title: Effects of selenium and silicon on enhancing antioxidative capacity in ramie (Boehmeria nivea (L.) Gaud.) under cadmium stress.
abstract: Hydroponic experiments were performed to investigate the ameliorating effects and mitigation mechanisms of selenium and silicon on Cd toxicity in Boehmeria nivea (L.) Gaud. Metal accumulation, chlorophyll content, activities of antioxidant enzymes, and antioxidant contents in ramie were evaluated. The results revealed that cadmium was mainly accumulated in the roots of plants rather than in the aerial parts. Additionally, under 5 mg L(-1) Cd stress, both Se (1 μmol L(-1)) and Si (1 mmol L(-1)) treatments decreased the Cd concentrations in plants. Besides, the treatments also inhibited the translocation ability of Cd from roots to the aboveground parts, which might be related to the decline of generation of reactive oxygen species (ROS). The application of Se and/or Si ameliorated Cd toxicity via stimulating the activities of antioxidant enzymes such as superoxide dismutase (SOD), guaiacol peroxidase (POD), and ascorbate peroxidase (APX), which resulted in the significant decrease of the contents of malondialdialdehyde (MDA) and hydrogen peroxide (H2O2) in ramie leaves. In addition, the content of nonenzymatic antioxidant such as glutathione (GSH) was increased significantly through the addition of selenite and silicate. Also, ascorbate (AsA) and vitamin E played a crucial role in scavenging excess ROS within plants. On the whole, appropriate doses of Se and Si were found to benefit plant growth and enhance the ability of ramie to alleviate Cd-induced stress. Moerover, the effects of combination of Se and Si appeared to be more superior compared to addition separately in response to Cd stress.
authors: College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China.
authors: Hui
authors: H
authors: Tang
authors: Yunguo
authors: Y
authors: Liu
authors: Xiaomin
authors: X
authors: Gong
authors: Guangming
authors: G
authors: Zeng
authors: Bohong
authors: B
authors: Zheng
authors: Dafei
authors: D
authors: Wang
authors: Zhichao
authors: Z
authors: Sun
authors: Lu
authors: L
authors: Zhou
authors: Xiaoxia
authors: X
authors: Zeng
mesh_terms: D060387:Ascorbate Peroxidases / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D032402:Boehmeria / Q000502:physiology*; D002104:Cadmium / Q000633:toxicity*; D002734:Chlorophyll / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide; D018384:Oxidative Stress / Q000528:radiation effects; D009195:Peroxidase; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000494:pharmacology; D012643:Selenium / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D012989:Soil Pollutants / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D012989:Soil Pollutants; D002104:Cadmium; D002734:Chlorophyll; D006861:Hydrogen Peroxide; C121048:guaiacol peroxidase; D060387:Ascorbate Peroxidases; D009195:Peroxidase; D013482:Superoxide Dismutase; D005978:Glutathione; D012643:Selenium; D001205:Ascorbic Acid; D012825:Silicon