Pretreatment with Stenotrophomonas maltophilia CGMCC 1.1788 increased the aphicidal activity of imidacloprid

When imidacloprid was first pretreated in a solution of Stenotrophomonas maltophilia CGMCC 1.1788 in the presence of succinate for 8 days and then applied directly to soils, its aphicidal activity was raised more than twofolds. Analysis explored that a part of imidacloprid was cometabolically biotransformed to highly active metabolites. This paper offers a new, economical way to apply bacterial transformation to improve insecticidal activity, which can decrease the dosage of imidacloprid and reduce environmental residue caused by insecticides.