Microbial degradation of chlorpyrifos and carbosulfan in sterile soil under laboratory conditions

Bacterial degradation of chlorpyrifos and carbosulfan in sterile soil under laboratory condition has been investigated at different concentrations (100, 200 and 300 μg g–1 of soil for chlorpyrifos and 100 and 400 μg g–1 of soil for carbosulfan). HPLC data of chlorpyrifos after 60 days of sampling revealed that the insecticide has degraded to 98.48, 98.22 and 95.19 per cent from its initial concentrations of 100, 200 and 300 μg g⁻¹ in sterile soil. Whereas, the degradation percentages were 29.58, 37.16 and 28.40 after 60 days from the control samples without microbial consortium. Similarly, 100 per cent degradation for carbosulfan in sterile soil by microbial consortium was achieved at 30 days after treatment for 100 μg g⁻¹ and at 60 days for 400 μg g⁻¹ compared to control. Faster degradation by bacterial consortium was recorded for both the insecticides which followed pseudo first order rate kinetics. The study confirmed that microbial consortium could effectively be utilized for faster bioremediation of these insecticides in sterile soil under laboratory conditions. This consortium can also be used for effective biodegradation of two insecticides in mango orchard soil under field conditions.