Study the effect of Topsin (Thiophanate-Methyl) fungicide on E. coli bacteria

Abstract

This study aimed to know the effect of three concentration of Topsin fungicide (0.05, 0.005, 0.0005) mg/l on E. coli colony isolated from sediment of Euphrates river and find if possible half lethal LC50 from pesticide to bacteria. The results appeared that different concentrations have different effects on bacterial colonies growth which were average (137-232) colony/ml, (462-538) colony/ml and (605-657) colony/ml with percentage (17.41-29.71)%, (60.16-65.44)% and (71.51-83.06)% to three concentration respectively. The result pointed to the value of LC50 was 0.0099 mg/l. Also test tubes that have pesticide showed growth, which pointed to bacteria adaption for these concentration. the results pointed to a significant differentiation between growth average in probability at level (0.05) and reverse correlation coefficient between concentration and average of growth.