African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5231

Full Length Research Paper

In vitro effects of four heavy metals on glyphosate utilization by some bacteria isolated from rice fields

Okpala N. Gloria* and A. N. Moneke
  Department of Microbiology, University of Nigeria, Nsukka, Enugu State, Nigeria.  
Email: [email protected]

  •  Accepted: 04 August 2010
  •  Published: 18 August 2010



The effect of heavy metals (zinc, cadmium, chromium and lead) at concentrations 50, 100 and 500 μg/ml of the heavy metal salts on glyphosate utilization by some bacterial species isolated from rice fields were studied, the addition of lead (Pb), cadmium (Cd) and zinc (Zn) to the glyphosate mineral salt medium used in growing the Acetobacter sp. significantly (P < 0.05) increased the rate of glyphosate utilization as indicated by the increase in the growth of the organism and could be attributed to easy uptake of the metal-glyphosate complex by the organism. The growth ofPseudomonas fluorescens was enhanced in the presence of zinc in the glyphosate medium, when compared to its growth in the medium without the heavy metals. This was followed by lead, cadmium and chromium, respectively.


Key words: Glyphosate herbicide, utilization, metal-glyphosate complex.