| dc.description.abstract | Agricultural soil contamination caused due to immense use of pesticides in agricultural
fields has evolved into a global health and environmental hazard. A number of microorganisms are able to survive under extreme conditions in the presence of acquired
tolerance due to the prolonged exposure to contaminants by utilising pesticides and their
metabolites as the source of carbon, nitrogen or phosphorus. The aim of the current study
was to isolate glyphosate- tolerant and degrading bacteria from glyphosate-contaminated
soil collected from an agricultural field in Sabaragamuwa province, Sri Lanka that can
be applied for soil remediation aspects. Two bacterial strains isolated from glyphosate contaminated soil were analysed spectrophotometrically for 96 hrs. by measuring the
bacterial growth at 600 nm with the use of biotic control with no pesticide and by
measuring the pesticide concentration at the absorbance maxima of glyphosate with
abiotic control containing uninoculated Nutrient Broth supplemented with glyphosate,
in order to evaluate the dose- response and pesticide degrading ability respectively.
The two isolated strains, namely Arthrobacter sp. and Bacillus sp. survived in the
presence of different glyphosate concentrations (0 mg/L - 100 mg/L) with glyphosate degrading potentials. The Arthrobacter sp. indicated the highest percentage of glyphosate
degradation of 93.84% followed by Bacillus sp. with 76.37% during 96 hrs. Moreover,
statistical analysis of the study disclosed that glyphosate degradation percentages between
the two strains were not significantly different (p > 0.05). However, both strains indicated
a statistical significance (p < 0.05) in degradation percentage compared to the abiotic
control, thus indicating the potential of using both strains for future bioremediation
studies. | en_US |
