Plant and Soil

, Volume 290, Issue 1, pp 103–114

Silicon-mediated changes of some physiological and enzymatic parameters symptomatic for oxidative stress in spinach and tomato grown in sodic-B toxic soil

Authors

    • Faculty of Agriculture, Department of Soil Science and Plant NutritionAnkara University
  • Ali Inal
    • Faculty of Agriculture, Department of Soil Science and Plant NutritionAnkara University
  • Esra Guneri Bagci
    • Faculty of Agriculture, Department of Soil Science and Plant NutritionAnkara University
  • David J. Pilbeam
    • Institute of Integrative and Comparative BiologyLeeds University
Original paper

DOI: 10.1007/s11104-006-9137-9

Cite this article as:
Gunes, A., Inal, A., Bagci, E.G. et al. Plant Soil (2007) 290: 103. doi:10.1007/s11104-006-9137-9

Abstract

We investigated effect of silicon (Si) on the growth, uptake of sodium (Na), chloride (Cl), boron (B), stomatal resistance (SR), lipid peroxidation (MDA), membrane permeability (MP), lipoxygenase (LOX) activity, proline (PRO) accumulation, H2O2 accumulation, non-enzymatic antioxidant activity (AA) and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) of spinach and tomato grown in sodic-B toxic soil. Si applied to the sodic-B toxic soil at 2.5 and 5.0 mM concentrations significantly increased the Si concentration in the plant species and counteracted the deleterious effects of high concentrations of Na, Cl and B on root and shoot growth by lowering the accumulation of these elements in the plants. Stomatal resistance, MP, MDA and the concentrations of H2O2 and PRO were higher in the plants grown in sodic-B toxic soil without Si: LOX activity of excised leaves of both species was increased by Si. Antioxidant activities of both species were significantly affected by Si, with the activities of SOD, CAT and APX decreased and AA increased by applied Si. For most of the parameters measured, it was found that 5 mM Si was more effective than the 2.5 mM Si. Based on the present work, it can be concluded that Si alleviates sodicity and B toxicity of the plants grown in sodic-B toxic soil by preventing both oxidative membrane damage and also translocation of Na, Cl and B from root to shoots and/or soil to plant, and lowering the phytotoxic effects of Na, Cl and B within plant tissues. It was concluded that tomato was more responsive to Si than spinach since it was more salt sensitive than spinach. To our knowledge, this is the first report that Si improves the combined salt and B tolerance of spinach and tomato grown in naturally sodic-B toxic soil, and which describes membrane-related parameters and antioxidant responses.

Keywords

Antioxidant enzymesB toxicityLipid peroxidationProlineNon-enzymatic antioxidantsSiliconSodicity

Abbreviations

AA

Non-enzymatic antioxidant activity

APX

Ascorbate peroxidase

CAT

Catalase

LOX

Lipoxygenase

MP

Membrane permeability

MDA

Malondialdehyde

NBT

Nitroblue tetrazolium

PRO

Proline

ROS

Reactive oxygen species

SOD

Superoxide dismutase

SR

Stomatal resistance

TBA

Thiobarbituric acid

TCA

Trichloroacetic acid

Copyright information

© Springer Science+Business Media B.V. 2006