ACTIVATION OF ATRAZINE METABOLISM BY THIOCARBAMATE HERBICIDES IN RHODOCOCCUS TE1

The addition of the thiocarbamate herbicide EPTC (s-ethyl-dipropylthiocarbamate) enhanced the degradation of atrazine by Rhodococcus TE1 initially by almost threefold. This enhancement by EPTC lasted until the bacterial culture attained its own full degradative capability. Atrazine on the other hand had no effect on EPTC degradation. Preincubation of the bacteria with EPTC showed a stimulatory effect on atrazine degradation similar to EPIC addition. Cells preincubated with atrazine showed the same extent of activation with EPTC as non-preincubated cells. Atrazine degradation was also activated by the addition of other thiocarbamates. N-Methylcarbamates which are also metabolized by this bacterium showed no effect on atrazine degradation. A soil adapted to EPTC degradation in the laboratory was also able to degrade atrazine.