biologia plantarum

Biologia plantarum 2012, 56:149-152 | DOI: 10.1007/s10535-012-0032-3

Comparison of antioxidant responses to cadmium and lead in Bruguiera gymnorrhiza seedlings

Y. M. Tao¹, Y. Z. Chen^1,2,*, T. Tan^1,2, X. C. Liu^1,2, D. L. Yang^1,2, S. C. Liang^1,2

¹ College of Life Science, Guangxi Normal University, Guilin, P.R. China

² Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, P.R. China

Seedlings of mangrove plant Bruguiera gymnorrhiza cultured in sand with Hoagland's nutrient solution were treated with 1 to 30 mM Cd(NO₃)₂ or Pb(NO₃)₂ for 2 months. In all Cd/Pb treatments, the malondialdehyde content increased while the chlorophyll content declined. Peroxidase (POD) and superoxide dismutase (SOD) activities in roots increased at moderate Cd/Pb concentrations (1-10 mM), whereas decreased at higher concentrations (20-30 mM). Catalase (CAT) activity in roots was inhibited by 1-10 mM Cd but enhanced by 1-10 mM Pb. The activities of POD, SOD and CAT in leaves were less affected by Cd and Pb than in roots. A new SOD and three CAT isoenzymes were induced by Pb. In contrast, no additional SOD and CAT isoenzymes were induced by Cd.

Keywords: antioxidant enzymes; catalase; mangrove; peroxidase; superoxide dismutase

Subjects: catalase; mangrove; peroxidase; superoxide dismutase; cadmium; lead; malondialdehyde; gene expression; chlorophyll

Species: Bruguiera gymnorrhiza

Received: October 21, 2009; Accepted: October 5, 2010; Published: March 1, 2012Show citation