biodegradation of atrazine in different concentrations by pseudomonas bacteria

abstract extensive application of atrazine and its toxicity in environmental has attracted researcher attention for finding new degradation methods to this organic pollutant. biodegradation is one of most effective methods for removing atrazine. due to the importance of atrazine herbicide as an organic pollutant, a design carried out at factorial experiment in completely randomized design with three repeats. the experiment consisted of two pseudomonas bacteria (fluorescence and aeruginosa) and three levels of atrazine concentrations 100, 200 and 300 mg.l-1. the data of experiment showed that pseudomonas bacteria degraded atrazine significantly. pseudomonas fluorescence and pseudomonas aeruginosa degraded atrazine 45 % and 38.88% in 48 hours, respectively. pseudomonas fluorescence was more efficient than pseudomonas aeruginosa. results showed that the increasing of atrazine concentration led to more degradation of this herbicide by both bacteria. the most degradation by both pseudomonas bacteria was at 300 ppm concentration and the less degradation occurred at 100 ppm concentration.