title: Zinc induces distinct changes in the metabolism of reactive oxygen and nitrogen species (ROS and RNS) in the roots of two Brassica species with different sensitivity to zinc stress.
abstract: OBJECTIVE
  Zinc (Zn) is an essential micronutrient naturally present in soils, but anthropogenic activities can lead to accumulation in the environment and resulting damage to plants. Heavy metals such as Zn can induce oxidative stress and the generation of reactive oxygen and nitrogen species (ROS and RNS), which can reduce growth and yield in crop plants. This study assesses the interplay of these two families of molecules in order to evaluate the responses in roots of two Brassica species under high concentrations of Zn.
  
  
  METHODS
  Nine-day-old hydroponically grown Brassica juncea (Indian mustard) and B. napus (oilseed rape) seedlings were treated with ZnSO4 (0, 50, 150 and 300 µm) for 7 d. Stress intensity was assessed through analyses of cell wall damage and cell viability. Biochemical and cellular techniques were used to measure key components of the metabolism of ROS and RNS including lipid peroxidation, enzymatic antioxidants, protein nitration and content of superoxide radical ([Formula: see text]), nitric oxide (NO) and peroxynitrite (ONOO(-)).
  
  
  RESULTS
  Analysis of morphological root damage and alterations of microelement homeostasis indicate that B. juncea is more tolerant to Zn stress than B. napus. ROS and RNS parameters suggest that the oxidative components are predominant compared with the nitrosative components in the root system of both species.
  
  
  CONCLUSIONS
  The results indicate a clear relationship between ROS and RNS metabolism as a mechanism of response against stress caused by an excess of Zn. The oxidative stress components seem to be more dominant than the elements of the nitrosative stress in the root system of these two Brassica species.
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and fglgbr@gmail.com.
authors.forename: Gábor
authors.initials: G
authors.lastname: Feigl
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and.
authors.forename: Nóra
authors.initials: N
authors.lastname: Lehotai
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and.
authors.forename: Árpád
authors.initials: Á
authors.lastname: Molnár
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and.
authors.forename: Attila
authors.initials: A
authors.lastname: Ördög
authors.affiliation: Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, Granada, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Rodríguez-Ruiz
authors.affiliation: Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, Granada, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Palma
authors.affiliation: Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, Granada, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Corpas
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and.
authors.forename: László
authors.initials: L
authors.lastname: Erdei
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary and.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Kolbert
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D029688:Brassica napus / Q000187:drug effects* / Q000378:metabolism; D009149:Mustard Plant / Q000187:drug effects* / Q000378:metabolism; D010084:Oxidation-Reduction; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013312:Stress, Physiological; D015032:Zinc / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D015032:Zinc
keywords: Brassica juncea; Brassica napus; Indian mustard; RNS; ROS; excess zinc; nitrosative stress; oilseed rape; oxidative stress; protein nitration; reactive nitrogen species; reactive oxygen species