|BIONDI, ANTONIO - University Of Catania|
|WANG, XINGENG - University Of California|
|MILLER, JEFFREY - Oregon State University|
|MILLER, BETSEY - Oregon State University|
|SHEARER, PETER - Oregon State University|
|ZAPPALA, LUCIA - University Of Catania|
|SISCARO, GAETANO - University Of Catania|
|WALTON, VAUGHN - Oregon State University|
|DAANE, KENT - University Of California|
Submitted to: Journal of Insect Behavior
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/14/2017
Publication Date: 8/28/2017
Citation: Biondi, A., Wang, X., Miller, J.C., Miller, B., Shearer, P.W., Zappala, L., Siscaro, G., Walton, V.W., Hoelmer, K.A., Daane, K.M. 2017. Innate olfactory responses of Asobara japonica toward fruits infested by the invasive spotted wing Drosophila. Journal of Insect Behavior. https://doi.org/10.1007/s10905-9636-y.
Interpretive Summary: Insect parasitoids are widely used as biological control agents against various insect pests. These natural enemies can often detect and use their host’s odors as clues for locating the host in its natural habitat. We examined the olfactory responses of an Asian parasitoid of an invasive fly pest of berries, the spotted wing drosophila, toward various fruits infested by the fly. Adult parasitoids were attracted to volatile chemical compounds emitted by infested fruits. Our results showed that inexperienced parasitoids did not show any preference towards odors from different kinds of infested fruits. However, subsequent adult parasitoid exposure to fruit odors modified their response and preference for those odors. The ability of parasitoids to learn helps them to locate different kinds of fruits in nature that are infested by spotted wing drosophila.
Technical Abstract: Insect parasitoids are often manipulated to improve biological control programs for various arthropod pests. Volatile compounds can be a relevant cue used by most parasitoid hymenoptera for host or host microhabitat location. We studied olfactory responses of the braconid Asobara japonica Belokobylskij, an Asiatic endoparasitoid of the invasive pest Drosophila suzukii (Matsumura), toward its host and host substrates. Adult A. japonica displayed an innate attraction to undescribed volatile cues from infested host fruits irrespectively of the juvenile rearing experience, i.e. they respond to a novel cue subsequently used for microhabitat selection. These data suggest that A. japonica parasitoids mass-reared on artificial diet and factitious host (D. melanogaster) can successfully locate their hosts. Naïve female parasitoids did not show a preference towards any of the tested host media. However, the enforced adult experience with the rearing host medium modified the olfactory preference patterns toward non-natal host fruits. These findings provide evidence of associative learning during the adult stage of A. japonica, and demonstrate its plasticity in exploiting the volatiles from various fruits infested by D. suzukii.