Conclusions
The results of this study indicated that the application of the
insecticide imidacloprid negatively affected the SIR, enzyme
activities, nitrogen transformation and number of bacteria.
Species of microorganisms sensitive to imidacloprid might be
replaced by species that showed a higher tolerance to this
insecticide among indigenous microflora. The consequence
of these changes might be an increase in the numbers of
specific bacteria and decrease in the diversity of bacterial
community members, and might have resulted in the
decrease of soil microbial activity. Our previous and this
study clearly indicated that the changes in the structure of
the soil microbial community after imidacloprid application
may also have an impact on biochemical and microbial soil
functioning. However, the interactions between biotic and
abiotic factors are very complex and many environmental
factors may modify the reaction of microbial populations to
the insecticide imidacloprid.