Experimental Releases of Pupal Parasitoids to Control Piophila casei (L.) (Diptera: Piophilidae) in Ham Production

The use of biological control within an integrated pest management approach in stored food production is expected to increase, due to both the limitations of chemical methods and the rising focus on environmental sustainability. However, comprehensive biological control strategies for animal-derived products like meats, fish, and cheeses are still lacking. Dry-cured ham is an example of a preserved animal product that can be infested by various arthropods, such as Piophila casei (L.) (Diptera: Piophilidae), when stored. This study aimed to assess the effectiveness of releasing the pupal parasitoids Pachycrepoideus vindemiae (Rondani) (Hymenoptera: Pteromalidae) and Muscidifurax raptor Girault and Sanders (Hymenoptera: Pteromalidae) in controlling this dangerous fly in a ham production facility in Northern Italy. Data on total parasitism, emergence rates, sex ratio, and longevity were collected for M. raptor and P. vindemiae during the biological control experiments. It was found that both parasitoids could successfully parasitize pupae of P. casei in ham production, avoiding ham contamination. While the longevity and the sex ratio data did not show a significant difference between the two parasitoids, P. vindemiae demonstrated a significantly higher total parasitism and emergence rate, suggesting it as a more promising candidate under the conditions of this study. An assessment of the potential use of these parasitoids in a ham production facility is discussed.