Degradation of dicyandiamide by soil bacteria

Dicyandiamide (DCD) is well known to be an efficient nitrification inhibitor and, hence, applied in agriculture and horticulture. DCD blocks the first step in the oxidation of ammonium and, as a consequence, inhibits the formation of nitrate. Although produced and applied at a large scale the degradation of DCD, so far, has not been elucidated in detail. From DCD-utilizing mixed cultures the authors have isolated a number of bacterial strains capable of degrading DCD under pure culture conditions. In the present study the authors analyze the effect of temperature, aeration and DCD concentration on the degradation of DCD by one of the isolates.