title: Cadmium toxicity in Maize (Zea mays L.): consequences on antioxidative systems, reactive oxygen species and cadmium accumulation.
abstract: Increased cadmium (Cd) accumulation in soils has led to tremendous environmental problems, with pronounced effects on agricultural productivity. Present study investigated the effects of Cd stress imposed at various concentrations (0, 75, 150, 225, 300, 375 μM) on antioxidant activities, reactive oxygen species (ROS), Cd accumulation, and productivity of two maize (Zea mays L.) cultivars viz., Run Nong 35 and Wan Dan 13. Considerable variations in Cd accumulation and in behavior of antioxidants and ROS were observed under Cd stress in both maize cultivars, and such variations governed by Cd were concentration dependent. Exposure of plant to Cd stress considerably increased Cd concentration in all plant parts particularly in roots. Wan Dan 13 accumulated relatively higher Cd in root, stem, and leaves than Run Nong 35; however, in seeds, Run Nong 35 recorded higher Cd accumulation. All the Cd toxicity levels starting from 75 μM enhanced H2O2 and MDA concentrations and triggered electrolyte leakage in leaves of both cultivars, and such an increment was more in Run Nong 35. The ROS were scavenged by the enhanced activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione peroxidase in response to Cd stress, and these antioxidant activities were higher in Wan Dan 13 compared with Run Nong 35 at all Cd toxicity levels. The grain yield of maize was considerably reduced particularly for Run Nong 35 under different Cd toxicity levels as compared with control. The Wan Dan 13 was better able to alleviate Cd-induced oxidative damage which was attributed to more Cd accumulation in roots and higher antioxidant activities in this cultivar, suggesting that manipulation of these antioxidants and enhancing Cd accumulation in roots may lead to improvement in Cd stress tolerance.
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.|Department of Agronomy, University of Agriculture, Faisalabad, 48000, Pakistan.
authors.forename: Shakeel Ahmad
authors.initials: SA
authors.lastname: Anjum
authors.affiliation: Department of Agronomy, University of Agriculture, Faisalabad, 48000, Pakistan.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
authors.forename: Mohsin
authors.initials: M
authors.lastname: Tanveer
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.|College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
authors.forename: Saddam
authors.initials: S
authors.lastname: Hussain
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.
authors.forename: Mingchen
authors.initials: M
authors.lastname: Bao
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China. wanglc@swu.edu.cn.
authors.forename: Longchang
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Agronomy, University of Agriculture, Faisalabad, 48000, Pakistan.
authors.forename: Imran
authors.initials: I
authors.lastname: Khan
authors.affiliation: Department of Agronomy, University of Agriculture, Faisalabad, 48000, Pakistan.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Ullah
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
authors.forename: Shahbaz Atta
authors.initials: SA
authors.lastname: Tung
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
authors.forename: Rana Abdul
authors.initials: RA
authors.lastname: Samad
authors.affiliation: School of Agronomy, Anhui Agricultural University, Hefei, 230036, China.
authors.forename: Babar
authors.initials: B
authors.lastname: Shahzad
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000378:metabolism; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects*; D010088:Oxidoreductases / Q000032:analysis / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000032:analysis / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D002104:Cadmium; D010088:Oxidoreductases
keywords: Antioxidant system; Cadmium toxicity; Environmental pollution; Maize cultivar; Reactive oxygen species