title: Pretreatment with H(2) O(2) alleviates aluminum-induced oxidative stress in wheat seedlings.
abstract: Hydrogen peroxide (H(2) O(2) ) is a key reactive oxygen species (ROS) in signal transduction pathways leading to activation of plant defenses against biotic and abiotic stresses. In this study, we investigated the effects of H(2) O(2) pretreatment on aluminum (Al) induced antioxidant responses in root tips of two wheat (Triticum aestivum L.) genotypes, Yangmai-5 (Al-sensitive) and Jian-864 (Al-tolerant). Al increased accumulation of H(2) O(2) and O(2) (•-) leading to more predominant lipid peroxidation, programmed cell death and root elongation inhibition in Yangmai-5 than in Jian-864. However, H(2) O(2) pretreatment alleviated Al-induced deleterious effects in both genotypes. Under Al stress, H(2) O(2) pretreatment increased the activities of superoxide dismutase, catalase, peroxidase, ascorbate peroxidase and monodehydroascorbate reductase, glutathione reductase and glutathione peroxidase as well as the levels of ascorbate and glutathione more significantly in Yangmai-5 than in Jian-864. Furthermore, H(2) O(2) pretreatment also increased the total antioxidant capacity evaluated as the 2, 2-diphenyl-1-picrylhydrazyl-radical scavenging activity and the ferric reducing/antioxidant power more significantly in Yangmai-5 than in Jian-864. Therefore, we conclude that H(2) O(2) pretreatment improves wheat Al acclimation during subsequent Al exposure by enhancing the antioxidant defense capacity, which prevents ROS accumulation, and that the enhancement is greater in the Al-sensitive genotype than in the Al-tolerant genotype.
authors.affiliation: Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310029, China.
authors.forename: Fang Jie
authors.initials: FJ
authors.lastname: Xu
authors.forename: Chong Wei
authors.initials: CW
authors.lastname: Jin
authors.forename: Wen Jing
authors.initials: WJ
authors.lastname: Liu
authors.forename: Yong Song
authors.initials: YS
authors.lastname: Zhang
authors.forename: Xian Yong
authors.initials: XY
authors.lastname: Lin
mesh_terms: D000535:Aluminum / Q000378:metabolism / Q000633:toxicity*; D000975:Antioxidants / Q000378:metabolism; D001713:Biphenyl Compounds; D016923:Cell Death / Q000187:drug effects; D005070:Evans Blue / Q000378:metabolism; D005838:Genotype; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010851:Picrates; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D017382:Reactive Oxygen Species / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D014908:Triticum / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D017382:Reactive Oxygen Species; D005070:Evans Blue; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D000535:Aluminum; C004931:1,1-diphenyl-2-picrylhydrazyl