Combined microbiological test to assess changes in an organic matrix used to avoid agricultural soil contamination, exposed to an insecticide

Combined microbiological and molecular test (BiologEcoplate TM , denaturing gradient gel electrophoresis (DGGE) and Real Time PCR (qPCR)) were carried out to evaluate the impact of repeated diazinon (DZN) applications at high concentration (40 mg kg -1 ) on microbial communities in a microcosm simulating the organic matrix (straw (50%): peat (25%): soil (25%) vv -1 ) of a pesticide biopurification system (PBS). Pesticide dissipation was also evaluated. After three successive exposures with DZN the dissipation efficiency was high; DZN dissipation clearly accelerated in the organic matrix, achieving 87%, 93% and 96% respectively after the three applications. The results obtained with BiologEcoplate TM showed that the physiological profiles of