The impact of fruit fly gut bacteria on the rearing of the parasitic waspDiachasmimorpha longicaudata

Area-wide integrated pest management strategies against tephritid fruit flies include the release of fruit fly parasitic wasps in the target area. Mass rearing of parasitic wasps is essential for the efficient application of biological control strategies. Enhancement of fruit fly host fitness through manipulation of their gut-associated symbionts might also enhance the fitness of the produced parasitic wasps and improve the parasitoid rearing system. In the current study, we added three gut bacterial isolates originating fromCeratitis capitata(Wiedemann) and four originating fromBactrocera oleae(Rossi) (both Diptera: Tephritidae) to the larval diet ofC. capitataand used the bacteria-fed larvae as hosts for the development of the parasitic waspDiachasmimorpha longicaudata(Ashmead) (Hymenoptera: Braconidae). We evaluated the effect of the bacteria on wasp life-history traits and assessed their potential use for the improvement ofD. longicaudatarearing.Enterobactersp. AA26 increased fecundity and parasitism rate and accelerated parasitoid emergence.Providenciasp. AA31 led to faster emergence of both male and female parasitoids, whereasProvidenciasp. 22 increased the production of female progeny.Bacillussp. 139 increased parasitoid fecundity, parasitism rate, and production of female progeny.Serratiasp. 49 accelerated parasitoid emergence for both males and females and increased production of female progeny.Klebsiella oxytocadelayed parasitoid emergence andEnterobactersp. 23 decreased parasitoid fecundity and parasitism rate. Our findings demonstrate a wide range of effects of fruit fly gut symbionts on parasitoid production and reveal a great potential of bacteria use towards enhancement of parasitic wasp rearing.