Behavioral Interactions Between Spotted-Wing Drosophila (Drosophila Suzukii) and It’s Parasitoid the Samba Wasp (Ganaspis Brasiliensis)

Author: Dominic    Crowley

Major: Biology

Graduation Year: 2023

Thesis Advisor: Philip Fanning

Description of Publication: Past research has found that female Drosophila generally decrease their reproductive output in response to exposure to predators, including parasitoid wasps. However, no studies on behavioral changes induced by the endoparasitic wasp Ganaspis brasiliensis have been documented in the literature. G. brasiliensis has been identified as a biocontrol agent candidate against D. suzukii, with field trials currently underway across the contiguous United States. In this thesis, two experiments were performed: a behavioral observation assay measuring reproductive behaviors and an oviposition assay, a measure of reproductive activity. Female D. suzukii exposed to G. brasiliensis were observed to have depressed oviposition, producing fewer offspring than the unexposed. Decreased oviposition upon exposure to larval predators may be a strategy to increase survival of offspring, implicating an evolutionary tradeoff between offspring quality and quantity. These results indicate that the mere presence of G. brasiliensis alone may suppress D. suzukii populations, providing evidence for the suitable use of G. brasiliensis as a biocontrol agent.

Location of Publication:

URL to Thesis: https://digitalcommons.library.umaine.edu/honors/845/