Beyond viral detection: multitrophic effects of covert infection with an RNA virus in medfly.

Hernandez-Pelegrin, L.; Garcia-Martinez, R.; Llacer, E.; Nieves, L.; Llopis-Gimenez, A.; Catala-Oltra, M.; Dembilio, O.; Perez-Hedo, M.; Urbaneja, A.; Ros, V. I. D.; Beitia, F.; Herrero, S.

doi:10.1101/2022.11.25.517915

bioRxiv · 10.1101/2022.11.25.517915

Beyond viral detection: multitrophic effects of covert infection with an RNA virus in medfly.

Hernandez-Pelegrin, L.·Garcia-Martinez, R.·Llacer, E.·Nieves, L.·Llopis-Gimenez, A.·Catala-Oltra, M.·Dembilio, O.·Perez-Hedo, M.·Urbaneja, A.·Ros, V. I. D.·Beitia, F.·Herrero, S.

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Abstract

Summary/abstractO_ST_ABSBackgroundC_ST_ABSWith the advent of high-throughput sequencing, large sets of insect-infecting RNA viruses producing apparent asymptomatic infections are being discovered. In the Mediterranean fruit fly (medfly) Ceratitis capitata, an agricultural key pest of a wide range of fruits, up to 13 different RNA viruses have been described. Recent analysis demonstrated a wide distribution of these viruses in different medfly strains collected worldwide, but little is known about the interactions between those viruses and the medfly host. Previous studies suggested that a higher abundance of Ceratitis capitata nora virus (CcaNV) decreased medfly developmental time. Here, we investigated the effect of CcaNV on a broad range of parameters related to host fitness and its interaction with other trophic levels. ResultsCcaNV purified from a naturally infected medfly strain was used to infect CcaNV-free flies orally and subsequently monitor pupal weight, adult emergence, flying ability and longevity. Our results revealed detrimental effects associated with a CcaNV infection in the medfly, in terms of reduced pupal weight and reduced adult longevity. Moreover, we tested the influence of a CcaNV infection in medflies on the parasitism performance of Aganaspis daci, a medfly endoparasitoid used in biological control programs against medflies. Our results showed that A. daci progeny increased when parasitizing on CcaNV-infected larvae. ConclusionsOur results proved that covert RNA viruses can impact on the insect ecology, directly affecting its insect host biology and indirectly influencing multitrophic interactions.

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Hernandez-Pelegrin, L., Garcia-Martinez, R., Llacer, E., Nieves, L., Llopis-Gimenez, A., Catala-Oltra, M., Dembilio, O., Perez-Hedo, M., Urbaneja, A., Ros, V. I. D., Beitia, F., Herrero, S.. 2022-11-25. Beyond viral detection: multitrophic effects of covert infection with an RNA virus in medfly.. https://doi.org/10.1101/2022.11.25.517915

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