Location: Tropical Pest Genetics and Molecular Biology Research Unit
Title: Host range of a parasitoid wasp is linked to host susceptibility to its mutualistic viral symbiontAuthor
Coffman, Kelsey | |
Kauwe, Angela | |
GILLETTE, NATALIE - University Of Hawaii | |
BURKE, GAELEN - University Of Georgia | |
Geib, Scott |
Submitted to: Molecular Ecology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/19/2024 Publication Date: 7/30/2024 Citation: Coffman, K.A., Kauwe, A.N., Gillette, N.E., Burke, G.R., Geib, S.M. 2024. Host range of a parasitoid wasp is linked to host susceptibility to its mutualistic viral symbiont. Molecular Ecology. Article e17485. https://doi.org/10.1111/mec.17485. DOI: https://doi.org/10.1111/mec.17485 Interpretive Summary: Microbial symbionts are known to be a major driving force in the diversification of insects. Increasing data have illuminated the roles of mutualistic viruses in promoting the success of megadiverse insects called parasitoid wasps, which develop as parasites of other insects. Most known beneficial viral elements allow parasitoid wasps to specialize for survival within a single or a few closely related host species. An exception to this pattern is the wasp Diachasmimorpha longicaudata, which can develop within a wide range of tephritid fruit fly hosts. Here, we show that a beneficial virus produced by D. longicaudata likely contributes to the success of this parasitoid species and represents a rare form of host range expansion guided by a mutualistic virus. Technical Abstract: Parasitoid wasps are one of the most species-rich groups of animals on Earth, due to their ability to successfully develop as parasites of nearly all types of insects. Unlike most known parasitoid wasps that specialize within one or a few host species, Diachasmimorpha longicaudata is a generalist that can survive within multiple genera of tephritid fruit fly hosts, including many globally important pest species. D. longicaudata has therefore been widely released to suppress pest populations as part of biological control efforts in tropical and subtropical agricultural systems. In this study, we investigated the role of a mutualistic poxvirus in shaping the host range of D. longicaudata across three genera of agricultural pest species: two of which are permissive hosts for D. longicaudata parasitism and one that is a nonpermissive host. We found that permissive hosts Ceratitis capitata and Bactrocera dorsalis were highly susceptible to virus infection, displaying rapid virus replication and abundant fly mortality. However, the nonpermissive host Zeugodacus cucurbitae largely overcame virus infection, exhibiting substantially lower mortality and no virus replication. Further investigation of transcriptional dynamics during virus infection demonstrated hindered viral gene expression and limited changes in fly gene expression within the nonpermissive host compared to the permissive species, indicating that the host range of the viral symbiont may dictate the host range of D. longicaudata wasps. These findings also reveal that viral symbiont activity may be a major contributor to the success of D. longicaudata as a generalist parasitoid species and a globally successful biological control agent. |