A biosensor is a self-contained integrated device which is capable providing specific quantitative analytical information using biological recoginition element which is in direct spatial contact with tranducer element. Different biosensing compound viz.,enzymes, antibodies, microorganism and plant tissues are using in biosensors as a recoginition element. Different types of biosenors such as electrochemical, optical, calorimetric, Acoustic and immunosensors which are used for pesticide detection. Among them enzyme like AchE, BchE and organophoshorus hydrolyse based electrochemical biosensors...