In the present investigation, a total of 30soil samples were collected from five different sites in Makurdi metropolis to investigate the effect of cypermethrin on some soil bacteria. Physicochemical properties of the soil samples from various sites were determined using standard procedures. Some selected soil bacteria such as Escherichia coli, Klebsiella spp., Bacillus spp.,Staphylococcus spp.andProteusspp.were isolated by the use of serial dilution and pour plating method.The percentage prevalence of Isolates shows that a total of(10)bacteria were isolated with samples from High Level accounting for50% of the isolates,North bank 30%and Wurukum samples20%. Klebsiellaspp. accounted for30% of the isolates,Escherichia coli10%,Staphylococcus and Bacillus spp.all accounting for20% respectively.The resistance pattern of the isolates at different concentration(1-3%) of cypermethrin showed that all the isolates could grow in the presence of cypermethrin at1% except Bacillus spp.However at2%, only Klebsiellaspp. grew; Staphylococcusspp., Escherichia coli and Bacillus spp.were inhibited and therefore showed no growth.These findings revealed that cypermethrin had effects on the soil bacteria at higher concentration inhibiting their growth but tolerated at lower concentration. Therefore,indiscriminate use of insecticides should be avoided and more eco-friendly means of pest control should be employed to reduce the negative impact of synthetic pesticides on beneficial soil organisms.
Keywords: Cypermethrin, Resistance,Pesticide, Biomass, Eco-friendly