Evaluation of the efficacy and optimization of indigenous microbial isolate for herbicides (Paraquat Dichloride, Glyphosate, and Glyphosate isopropylamine) degradation

Abstract

The presence of herbicides in soil is a serious problem for the environment. Studies on degradation of Herbicide (Paraquate dichloride (PD), Rake out (RO) and Gobara (GB)) by bacteria and fungi species isolated from soil environment in Keffi Metropolis Nigeria were carried out. A total of twenty (20) soil samples were collected. The bacteria and fungi were isolated from the soil and identified using standard microbiological methods. The herbicides utilization was determined using Atomic Adsorption Spectrometer. The effect of temperature on utilization of the herbicides by Enterobacter asburiae at 26OC ranges from 1.23±0.11 mg/ml for PD, 1.14±0.29 mg/ml for RO and 0.53±0.86mg/ml for GB, Pseudomonas aeruginosa utilization ranges from 1.45±0.17 mg/ml for PD, 1.17±0.35 mg/ml, for RO 1.12± 0.82mg/ml for GB. Aspergillus flavus ranges from 2.12±0.19 mg/ml for PD, 2.00±0.03 mg/ml for RO and 2.02±0.57 mg/ml for GB, Fusarium redolens were 2.19±0.26 mg/ml for PD, 2.15±0.08 mg/ml for RO and 1.92±0.16 mg/ml for GB. Effect of incubation time on microbial herbicides degradations: for E. asburiae on PD it ranges from day 1 with 0.24±0.37 mg/ml to day 20 with 2.06±0.11 mg/ml. for P. aeruginosa on PD ranges from day 1 with 0.38±0.08 mg/ml to day 20 with 2.39±1.45 mg/ml. The Utilization of herbicides by A. flavus on PD ranges from day 1 with 0.10±0.01 mg/ml to day 20 with 2.29±0.12 mg/ml. for F. redolens in PD, it ranges from day 1 with 0.27±0.08 mg/ml to day 20 with 2.57±0.27mg/ml. The process of degradation of herbicide has become very attractive as it allows for removal of herbicide over a relatively broad range of pH and temperature