A narrow host-range and lack of persistence in two non-target insect species of a bacterial symbiont exploited to deliver insecticidal RNAi in Western Flower Thrips

Introduction Insecticidal RNAi is a targeted pest insect population control measure. The specificity of insecticidal can theoretically be enhanced by using symbiotic bacteria with narrow host range to deliver RNAi, an approach termed symbiont-mediated (SMR), technology we have previously demonstrated in the globally-invasive species Western Flower Thrips (WFT). Methods Here examine distribution two predominant bacterial symbionts WFT, BFo1 and BFo2, among genome-sequenced insects. Moreover, challenged non-target both species, namely pollinating European bumblebee, Bombus terrestris, predator pirate bug Orius laevigatus. Results Our data indicate very limited either symbiont insects other than WFT. whereas could establish itself bees bugs, albeit no significant effects on fitness, BFo2 was unable persist species. Discussion In terms biosafety, these data, together its more specific growth requirements, vindicate choice for delivery precision management