ABSTRACT

In this review we will describe the effects of the herbicide simazine on the qualitative and quantitative composition of soil bacterial and fungal populations, as well as their influence on production of B-groups vitamins and amino acids by Azotobacter spp. Compared with control soil, the herbicide simazine did not affect bacterial populations, fungi, aerobic dinitrogen-fixing bacteria, denitrifying bacteria, and nitrogenase activity. However, nitrifying bacteria were decreased at concentrations of 50 to 300 μg/g. The herbicide simazine affected the quantitative production of B-group vitamins (thiamin, niacin, pantothenic acid, cyanocobalamin and biotin) and amino acids (lysine and methionine).