Effect of Herbicide Clopyralid and Imazamox on Dehydrogenase Enzyme in Soil of Regenerated Pedunculate Oak Forests

Clopyralid and imazamox are successfully used for weed control during the first years of regeneration pedunculate oak forests. Hence, question that arises is how these herbicides affect microorganisms, especially activity dehydrogenase enzyme, when they reach soil. Two study sites were selected in regenerated forests, two applied doses (clopyralid, 100 g a.i. ha−1 120 ha−1; imazamox, 40 48 ha−1). The effect was evaluated 7, 14, 21, 30, 60 days after application. A significant reduction found on 7 14 at both sites. However, there a recovery all treatments such values obtained day 21 did not differ from values. clopyralid dose-dependent. Dehydrogenase also depended soil properties, sampling time climatic conditions investigation years. results show can reduce activity, but this transient. This be attributed to ability microorganisms overcome stress caused by herbicide developing capability utilize as nutrient source proliferating an environment.