Accumulation, tolerance and impact of aluminium, copper and zinc on growth and nitrate reductase activity of Ceratophyllum demersum (Hornwort)

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Date
2008
Authors
Umebese, C. E.
Motajo, A. F.
Journal Title
Journal ISSN
Volume Title
Publisher
Triveni Enterprises, Lucknow (India)
Abstract
Ceratophyllum demersum (hornwort) was subjected to toxic concentrations of Al (3 and 9 mg l -1), Zn (3 and 9 mg l -1) and Cu (2.5 and 7 mg l -1) in culture solutions for 15 days. The higher dose of Al enhanced the chlorophyll content significantly (p<0.05) in the first 6 days of treatment while other treatments caused marked reductions. Nitrate reductase activity (NRA) was significantly reduced (p<0.05) by Al, Cu and Zn toxicity and ceased completely in plants treated with Cu by the 6th day of treatment. Dry biomass and relative growth rate were reduced significantly (p<0.05) by metal treatment. Tolerance index of the plant was low for Cu (21.62 and 13.43% at low and high doses, respectively) and moderate for Zn (63.74 and 54.85%) and Al (72.83 and 68.79%). Accumulation of Al, Zn and Cu was threefold at higher doses compared with the lower doses but the bioconcentration factors (BCF) were very low indicating that this plant is not a hyper accumulator of these metals.
Description
Keywords
Al , Zn , Cu , Tolerance index , Chlorophyll , Growth , Nitrate reductase activity
Citation
Umebese, C. E. and Motajo, A. F. (2008). Accumulation, tolerance and impact of aluminium, copper and zinc on growth and nitrate reductase activity of Ceratophyllum demersum (Hornwort). Journal of Environmental Biology 29(2): 197 - 200