title: Alleviating effects of calcium on cobalt toxicity in two barley genotypes differing in cobalt tolerance.
abstract: Cobalt (Co) contamination in soils is becoming a severe issue in environment safety and crop production. Calcium (Ca),as a macro-nutrient element, shows the antagonism with many divalent heavy metals and the capacity of alleviating oxidative stress in plants. In this study, the protective role of Ca in alleviating Co stress was hydroponically investigated using two barley genotypes differing in Co toxicity tolerance. Barley seedlings exposed to 100µM Co showed the significant reduction in growth and photosynthetic rate, and the dramatic increase in the contents of reactive oxygen species (ROS), malondialdehyde (MDA), reduced glutathione (GSH) and oxidized glutathione (GSSG), and the activities of anti-oxidative enzymes, with Ea52 (Co-sensitive) being much more affected than Yan66 (Co-tolerant). Addition of Ca in growth medium alleviated Co toxicity by reducing Co uptake and enhancing the antioxidant capacity. The effect of Ca in alleviating Co toxicity was much greater in Yan66 than in Ea52. The results indicate that the alleviation of Co toxicity in barley plants by Ca is attributed to the reduced Co uptake and enhanced antioxidant capacity.
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China; Department of Crops sciences, Faculty of Agronomy, University of Lubumbashi, PO Box 1825, Lubumbashi, Democratic Republic of the Congo.
authors.forename: Jonas Lwalaba Wa
authors.initials: JL
authors.lastname: Lwalaba
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China.
authors.forename: Gerald
authors.initials: G
authors.lastname: Zvobgo
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China.
authors.forename: Liangbo
authors.initials: L
authors.lastname: Fu
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China.
authors.forename: Xuelei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China; Department of Crops sciences, Faculty of Agronomy, University of Lubumbashi, PO Box 1825, Lubumbashi, Democratic Republic of the Congo.
authors.forename: Theodore Mulembo
authors.initials: TM
authors.lastname: Mwamba
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China.
authors.forename: Noor
authors.initials: N
authors.lastname: Muhammad
authors.affiliation: Department of Crops sciences, Faculty of Agronomy, University of Lubumbashi, PO Box 1825, Lubumbashi, Democratic Republic of the Congo.
authors.forename: Robert Prince Mukobo
authors.initials: RP
authors.lastname: Mundende
authors.affiliation: Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, P.R China. Electronic address: zhanggp@zju.edu.cn.
authors.forename: Guoping
authors.initials: G
authors.lastname: Zhang
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002118:Calcium / Q000494:pharmacology*; D003035:Cobalt / Q000633:toxicity*; D004347:Drug Interactions; D005838:Genotype; D005978:Glutathione / Q000378:metabolism; D001467:Hordeum / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D012989:Soil Pollutants; D003035:Cobalt; D008315:Malondialdehyde; D005978:Glutathione; D002118:Calcium
keywords: Alleviation; Barley; Calcium; Cobalt; Oxidative stress; Tolerance