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The present study has been carried out in order to determine the entomofauna of four different agroecosystems from the study area, northwestern Algeria. Regular sampling was done using the Barber pitfall trap and the sweep net in addition to visual observations in the field. Nine (09) taxonomic orders of insects was identified from the four studied environments. It varies from one agroecosystem to another. Coleoptera and Orthoptera were the most represented in terms of both species and numbers. Entomofaunal diversity was more important in un-cultivated fields (diversity index = 4.15 bits, equitability = 0.89) than in arable fields (index ranging from 1.68 to 2.87 and a equitability between 0.41 and 0.72). Limited biodiversity in cultivated areas was the consequence of insect communities’ interactions disturbances caused by agricultural practices in these environments. Therefore, it is important to reduce these disturbances in order to enhance food resources, habitats and overwintering sites for insects. This will ensures sustainable entomological diversity, thereby increasing the role of biological control in pest management systems.

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During the last decade, plant and microbial-derived metabolites have received growing attention as potential tools for pest management in agriculture. Pederin (C₂₅H₄₅NO₉) is a vesicant toxin produced by Pseudomonas-like bacterial symbionts of rove beetles within the genus Paederus (Col: Staphylinidae). In this study, the toxicity of pederin to two stored product pests, Ephestia kuehniella Zeller (Lep: Pyralidae) and Tribolium confusum Jacquelin du Val (Col: Tenebrionidae) was evaluated using laboratory bioassays. Probit analysis estimated the median lethal concentrations of pederin as 1311.96 and 596.36ppm for E. kuehniella fourth larval instar and T. confusum adults, respectively. We also measured the activity of two major digestive enzymes (amylases and proteases) as well as three major detoxifying enzymes (P_450s monooxygenases, glutathione S-transferases, and carboxyl esterases) in insects treated orally with pederin. Feeding on pederin resulted in significant decrease in the activity of amylolytic, proteolytic, and carboxyl esterase enzymes, but significant increase in the activity of P_450s and glutathione S-transferases. Results of this study may highlight pederin as a novel source of pesticides with unique mode of action for use in pest management programs.