Effects of Beauveria bassiana on Frankliniella occidentalis(Thysanoptera: Thripidae) through different routes of exposure

Abstract: Beauveria bassiana is an entomopathogenic fungus widely used in biocontrol tacticsover the world. Its potential has been tested on several pest species, included the Western FlowerThrips Frankliniella occidentalis Pergande. However, knowledge on B. bassiana-thrips interactionsis limited. In laboratory bioassays, we exposed different developmental stages ofF. occidentalis (first and second instar larvae, adults) to residual or topical applications of aB. bassiana commercial strain (strain ATCC 74040, Naturalis®). A moderate to high mortalitywas noticed for first instar larvae, late second instar larvae and adults when the two routes ofexposure were combined. The results stress on the importance to favor the contact of thrips withB. bassiana to obtain satisfactory control of this pests. The significant reduction in thrips survivalafter B. bassiana applications suggests that the latter can be included in IPM tactics.