Effect of Butachlor on Soil Microbial Populations and Enzyme Activities

The effect of butachlor on soil microbial populations and enzyme activities was investigated in a microcosm mimicing soil ecosystem. The effect of butachlor at rates of 2 mg/kg and 4 mg/kg on soil microbial population is a temporal phenomenon and disappears within a few days. However, butachlor at high rate of 10 mg/kg inhibited soil microbial population significantly till 21 days after treatments. The activities of acid phosphatase, alkaline phosphatase, urease and invertase in soil treated with butachlor were all inhibited. The inhibitory effect disappeared gradually with time, and enzyme activities recovered to the levels of the control without butachlor. The influence of butachlor on catalase was different from acid phosphatase, alkaline phosphatase, urease and invertase, an enhancement effect was observed.