Effect of butachlor (G) on soil enzyme activity

Soil enzymes play a crucial role in maintaining soil functions. Pesticide application to crop plants can potentially interfere with soil enzyme activity. We evaluated the impact of butachlor (G), a widely used herbicide, on total soil microbial activity and activity of various soil enzymes, including alkaline phosphatase, protease, urease and amidase at different application rates under flooded and un-flooded conditions in a laboratory experiment. The pesticide treatment had an inhibitory effect on dehydrogenase activity under un-flooded conditions and stimulatory effect under flooded conditions. Phosphatase activity was stimulated under most of the applied concentrations both under flooded as well as un-flooded conditions. Protease activity was initially stimulated but decreased towards the end of the experiment under un-flooded conditions. Under flooded conditions the effect of butachlor on the activity of protease was stimulatory. Urease activity was reduced by pesticide treatment under un-flooded conditions, but response was inconsistent under flooded conditions. Amidase activity showed a fluctuating behaviour. Thus, the results allowed us to conclude that the use of butachlor alters soil enzyme activity, and its potential implications could be examined by future studies.