Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Tolerance and phytoaccumulation of Chromium by three Azolla species


Azolla, an aquatic fern is ideal candidate for exploitation in constructed wetlands for treating metal-contaminated wastewaters. This study demonstrates the potential of Azolla spp. namely A. microphylla, A. pinnata and A.␣filiculoides to tolerate Cr ions in the growth environment and bioconcentrate them. These species could grow in presence of up to 10 μg ml−1 Cr and showed biomass production 30–70% as compared to controls. Nitrogenase activity was not affected at 1–5 μg ml−1 but at higher concentrations it diminished. There was no growth at higher concentrations of chromium. However, the necrosed biomass harvested from treatments containing higher concentrations of chromium, accumulated Cr to the levels 5000–15,000 μg g−1. At increased levels of Cr, the metal was accumulated in higher amount in dry biomass. Bioconcentration Factor (BCF) ranged between 243 and 4617 for the three species. A. microphylla showed highest bioconcentration potential. Thus, these Azolla spp. can be exploited for treatment of tannery and other Cr contaminated wastewaters.

This is a preview of subscription content, log in to check access.


  1. Acar F.N., Malkoc E., 2004 The removal of Chromium VI from aqueous solutions by Fagus orientalis L Bioresource Technology 94: 13–15

  2. Aravindhan R., Madhan B., Raghav Rao J., Nair B.U., Ramasami T., 2004 Bioaccumulation of chromium from tannery wastewater: an approach for chrome recovery and reuse Environmental Science and Technology 38:301–306

  3. Arora A., Singh P.K., 2001 Use of Azolla in bioremediation. In Singh P.K., Dhar D.W., Pabbi S., Prasanna R., Arora A., (eds) Recent Advances in Exploitation of Blue-Green Algae and Azolla Venus Printers and Publishers, N. Delhi pp.129–137

  4. Arora A., Singh P.K., 2003 Comparison of biomass productivity and nitrogen fixing potential of Azolla spp. Biomass and Bioenergy 24: 175–178

  5. Black H., 1995 Absorbing possibilities: Phytoremediation Environmental Health Perspective 103: 1106–1108

  6. Boonyapookana B., Upatham S.E., Kruatrachue M., Pokethitiyook P., Singhakaew S., 2002 Phytoaccumulation and phytotoxicity of cadmium and chromium in duckweed Wolffia globosa International Journal of Phytoremediation 4: 87–100

  7. Chhonkar P.K., Datta S.P., Joshi H.C., Pathak H., 2000 Impact of industrial effluents on soil health and agriculture–Indian Experience: Part II-Tannery and textile industrial effluents Journal of Scientific and Industrial Research 59: 446–454

  8. Cohen-Shoel N., Ilzycer D., Gilath I., Tel-Or E., 2002 The involvement of pectin in Sr2 + biosorption by Azolla Water Air and Soil Pollution 135: 195–205

  9. Garg V.K., Gupta R., Kumar R., Gupta R.K., 2004 Adsorption of chromium from aqueous solution on treated sawdust Bioresource Technology 92: 79–81

  10. Hagemeyer J., 1999 Ecophysiology of plant growth under heavy metal stress. In Prasad M.N.V, Hagemeyer J., eds Heavy Metal Stress in Plants Springer-Verlag, Berlin, Heidelberg. pp. 157–181 ISBN 3540654690

  11. Jain S.K., Vasudevan P., Jha N.K., 1989 Removal of some heavy metals from polluted water by aquatic plants: Studies on duckweed and water velvet Biological Waste 28: 115–126

  12. Jain S.K., Vasudevan P., Jha N.K., 1990 Azolla pinnata R.Br and Lemna minor L for removal of Lead and zinc from polluted water Water Research 24:177–183

  13. Oke, B.H. & Juwarkor, A.S. 1996 Removal of heavy metals from domestic wastewater using constructed wetland. 5th International Conference on Wetland Systems for Water Pollution Control, Vienna, September 15–19

  14. Rai U.N., Chandra P., 1992 Accumulation of copper, lead, manganese and iron by field population of Hydrodictyon reticulum Lagerheim Science of the Total Environment 116: 203–211

  15. Raskin I., Kumar P.B.A.N., Dushenkov S., Salt D.E., 1994 Bioconcentration of heavy metals by plants Current Opinions in Biotechnology 28: 115–126

  16. Salt D.E., Blaylock M., Kumar P.B.A.N., Dushenkov V., Ensley B.D., Chet I., Raskin I., 1995 Phytoremediation: a novel strategy for the removal of toxic metals from the environment using plants Biotechnology 13: 468–474

  17. Sela M., Garty J., Tel-Or E., 1989 The accumulation and effect of heavy metals on the water fern Azolla filiculoides New Phytologist 112: 7–12

  18. Sharpe V., Denny P., 1976 Electron microscope studies on the absorption and localization of Lead in the leaf tissue of Potamogeton pectinatus L Journal of Experimental Botany 27: 1135–1162

  19. Tribune News Service. 2004 Can discharge of total chrome in Drain be carcinogenic. The Tribune. June 7

  20. Volesky B., 1990 Biosorption of Heavy Metals CRC Press, Boca Raton. ISBN 0849349176

  21. Wagner G.M., 1997 Azolla: A review of its biology and utilization Botanical Reviews 1–26

  22. Watanabe I., Espinas, C.R., Berja, N.S. & Alimango, B.V. 1977 Utilisation of Azolla-Anabaena Complex as a Nitrogen fertilizer for rice. IRRI Research Paper Series. 11: 1–6

  23. Zayed A., Gowthaman S., Terry N., 1998 Phytoaccumulation of trace elements by wetland plants: I. Duckweed Environment Quality 27: 715–721

  24. Zhao M., Duncan J.R., 1997 Batch removal of sexivalent Chromium by Azolla filiculoides Biotechnology and Applied Biochemistry 26: 179–182

Download references

Author information

Correspondence to Anju Arora.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Arora, A., Saxena, S. & Sharma, D.K. Tolerance and phytoaccumulation of Chromium by three Azolla species . World J Microbiol Biotechnol 22, 97–100 (2006).

Download citation

Key words:

  • Azolla species
  • bioremediation
  • chromium
  • heavy metal
  • phytosorption
  • wastewaters