title: The effects of short-term selenium stress on Polish and Finnish wheat seedlings-EPR, enzymatic and fluorescence studies.
abstract: Biochemical analyses of antioxidant content were compared with measurements of fluorescence and electron paramagnetic resonance (EPR) to examine the alteration of radicals in wheat seedlings exposed to 2 days of selenium stress. Two genotypes of Polish and one of Finnish wheat, differing in their tolerance to long-term stress treatment, were cultured under hydroponic conditions to achieve the phase of 3-leave seedlings. Afterwards, selenium (sodium selenate, 100 μM concentration) was added to the media. After Se-treatment, all varieties showed an increase in carbohydrates (soluble and starch), ascorbate and glutathione content in comparison to non-stressed plants. These changes were more visible in Finnish wheat. On the basis of lipid peroxidation measurements, Finnish wheat was recognized as the genotype more sensitive to short-term Se-stress than the Polish varieties. The antioxidant enzyme activities (superoxide dismutase, ascorbate peroxidase and glutathione reductase) increased in Polish genotypes, whereas they decreased in Finnish wheat plants cultured on Se media. The action of reactive oxygen species in short-term action of Se stress was confirmed by the reduction of PSII and PSI system activities (measured by fluorescence parameters and EPR, respectively). EPR studies showed changes in redox status (especially connected with Mn(II)/Mn(III), and semiquinone/quinone ratios) in wheat cell after Se treatment. The involvement of the carbohydrate molecules as electron traps in production of long-lived radicals is postulated.
authors.affiliation: Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland. labanows@chemia.uj.edu.pl
authors.forename: Maria
authors.initials: M
authors.lastname: Łabanowska
authors.forename: Maria
authors.initials: M
authors.lastname: Filek
authors.forename: Janusz
authors.initials: J
authors.lastname: Kościelniak
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kurdziel
authors.forename: Ewa
authors.initials: E
authors.lastname: Kuliś
authors.forename: Helina
authors.initials: H
authors.lastname: Hartikainen
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D005387:Finland; D014644:Genetic Variation; D005838:Genotype; D005980:Glutathione Reductase / Q000378:metabolism; D015227:Lipid Peroxidation; D009195:Peroxidase / Q000378:metabolism; D045331:Photosystem I Protein Complex / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D011044:Poland; D017382:Reactive Oxygen Species / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D064586:Selenic Acid; D012643:Selenium / Q000378:metabolism / Q000494:pharmacology*; D018036:Selenium Compounds / Q000378:metabolism / Q000494:pharmacology; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000378:metabolism; D014908:Triticum / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism
chemical_list: D000975:Antioxidants; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D017382:Reactive Oxygen Species; D018036:Selenium Compounds; D060387:Ascorbate Peroxidases; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D012643:Selenium; D064586:Selenic Acid