摘要：This research was initiated to investigate the antimicrobial activity of Spinosad (Microbial metabolite) which is a new type of insecticide with natural origin was studied for its activity against selected soil beneficial microbes and plant pathogenic microbes were tested against spinosad for its activity. The activity of spinosad was tested against soil beneficial and plant pathogenic microbes by disc diffusion method. The spinosad was prepared at 1 ppm, 5 ppm & 10 ppm concentrations and tested against bacteria & fungi. The mean and S.D value of soil beneficial bacteria against spinosad at 1ppm concentration was 2±3.46 (95% confidence level), at 5ppm concentration 2.33±4.04,and at 10 ppm concentration the value was 4.66±4.04.the activity of spinosad against soil beneficial bacteria was low when compared to plant pathogenic bacteria when comparing the results, The mean and S.D of plant pathogenic bacteria at 1ppm was (12±7), at 5 ppm (13.66±1.15) and at10 ppm (15±2) so, from this results we have concluded that spinosad is harmless to soil beneficial bacteria and fungi whereas harmful to disease causing Plant pathogenic microbes.
