African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6578

Full Length Research Paper

Plasma membrane NADPH oxidase and apoplastic POD can be responsible for accumulation of H2O2 in mesophyll cells of Elsholtzia haichowensis under copper stress

Dong Yuan
Department of Civil Engineering, Luoyang Institute of Science and Technology, Luoyang 471023, China.
Email: [email protected]

  •  Accepted: 15 June 2012
  •  Published: 02 May 2013

Abstract

Under copper (Cu) stress, the activities of some enzymes involved in the antioxidant defense system in leave cells of Cu accumulator Elsholtzia haichowensis were investigated. Our results showed that Cu treatment significantly increased the activities of plasma membrane-bound nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, apoplastic peroxidase (POD), apoplastic superoxide dismutase (SOD), symplastic SOD and symplastic ascorbate peroxidase (APX) in leaves of E. haichowensis, when additional treatment with N-N-diethyldithiocarbamate as an inhibitor of SOD, NaN3 as an inhibitor of peroxidase, diphenyleneiodonium as an inhibitor of NADPH oxidase and 1, 2-dihydroxybenzene-3, 5-disulphonic acid as an O2- scavenger and Cu-induced activities of antioxidant enzymes in leave cells of E. haichowensis were significantly inhibited. The results suggested that plasma membrane NADPH oxidase and apoplastic POD can be responsible for the accumulation of H2O2 in mesophyll cells of E. haichowensis under copper stress. In the leaf symplast, however, Cu-induced activities of SOD and APX may be important in avoiding the build-up of toxic H2O2concentrations.

 

Key words: Elsholtzia haichowensis, leave, copper, inhibitor, antioxidant enzyme.