Isolation and identification of Cypermethrin degrading bacteria

In this study, five soil samples were collected from the Poisar Crop Field, where Cypermethrin pesticides were applied by the farmer. Successive enrichment techniques were used to isolate bacterial strains capable of breaking down high concentrations of Cypermethrin from the soil. A total of 67 microorganisms were isolated, among which seven bacterial strains (VY6, VY18, VY31, VY37, VY54, VY59, and VY62) demonstrated pesticide-degrading capabilities. Both qualitative and quantitative screenings were conducted on the isolated strains, out of that only one strain, VY54, could degrade high concentrations of Cypermethrin effectively. Strain VY54 grew in a pH range of 5 to 7 and exhibited a broad temperature tolerance from 28°C to 37°C. The isolated bacteria were identified based on their Gram staining characteristics, biochemical properties, and classification following Bergey’s Manual of Systematic Bacteriology, confirming the isolate VY54 as Pseudomonas sp. Subsequently, an antibiotic sensitivity test was conducted on the bacteria using the disc diffusion method.