Simultaneous Silencing of Gut Nucleases and a Vital Target Gene by Adult dsRNA Feeding Enhances RNAi Efficiency and Mortality in <i>Ceratitis capitata</i>
Gennaro Volpe,
Sarah Maria Mazzucchiello,
Noemi Rosati,
Francesca Lucibelli,
Marianna Varone,
Dora Baccaro,
Ilaria Mattei,
Ilaria Di Lelio,
Andrea Becchimanzi,
Ennio Giordano,
Marco Salvemini,
Serena Aceto,
Francesco Pennacchio,
Giuseppe Saccone
Affiliations
Gennaro Volpe
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Sarah Maria Mazzucchiello
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Noemi Rosati
Department of Agricultural Sciences, University of Naples “Federico II”, Portici, 80055 Naples, Italy
Francesca Lucibelli
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Marianna Varone
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Dora Baccaro
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Ilaria Mattei
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Ilaria Di Lelio
Department of Agricultural Sciences, University of Naples “Federico II”, Portici, 80055 Naples, Italy
Andrea Becchimanzi
Department of Agricultural Sciences, University of Naples “Federico II”, Portici, 80055 Naples, Italy
Ennio Giordano
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Marco Salvemini
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Serena Aceto
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Francesco Pennacchio
Department of Agricultural Sciences, University of Naples “Federico II”, Portici, 80055 Naples, Italy
Giuseppe Saccone
Department of Biology, University of Naples “Federico II”, 80126 Naples, Italy
Ceratitis capitata, known as the Mediterranean fruit fly (Medfly), is a major dipteran pest significantly impacting fruit and vegetable farming. Currently, its control heavily relies mainly on chemical insecticides, which pose health risks and have effects on pollinators. A more sustainable and species-specific alternative strategy may be based on double-stranded RNA (dsRNA) delivery through feeding to disrupt essential functions in pest insects, which is poorly reported in dipteran species. Previous reports in Orthoptera and Coleoptera species suggested that dsRNA degradation by specific nucleases in the intestinal lumen is among the major obstacles to feeding-mediated RNAi in insects. In our study, we experimented with three-day adult feeding using a combination of dsRNA molecules that target the expression of the ATPase vital gene and two intestinal dsRNA nucleases. These dsRNA molecules were recently tested separately in two Tephritidae species, showing limited effectiveness. In contrast, by simultaneously feeding dsRNA against the CcVha68-1, CcdsRNase1, and CcdsRNase2 genes, we observed 79% mortality over seven days, which was associated with a decrease in mRNA levels of the three targeted genes. As expected, we also observed a reduction in dsRNA degradation following RNAi against nucleases. This research illustrates the potential of utilizing molecules as pesticides to achieve mortality rates in Medfly adults by targeting crucial genes and intestinal nucleases. Furthermore, it underscores the importance of exploring RNAi-based approaches for pest management.