Population of Cotesia vestalis, an endolarval parasitoid of Diamondback moth Plutella xylostella an important pest of crucifer crops was collected from different geographical locations in India. The gut bacteria (endosymbionts) of C.vestalis were isolated and identified. Predominant among them, Enterobacter cancerogenus was evaluated for its role in pesticide degradation of the widely used organophosphorus insecticide, Acephate. Growth of the bacterium on minimal salt media utilizing the pesticide as carbon source and reduced peaks of the degradative product in Liquid Chromotagraphy Mass Spectrometry (LCMS) analysis confirmed the role of the bacterium in the degradation of the pesticide. The association of the symbiont contributed to pesticide resistance in the parasitoid. The effective utilization of the symbiont in pest management programme is discussed.
