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Red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier 1790) is a highly invasive species originating from Southeast Asia and Melanesia. Over the past 30 years, this alien pest has spread extensively in the Middle East and the Mediterranean basin. Its endophagous larvae feed on various palm species, causing significant damage that leads to the death of palm trees. Controlling RPW infestations is challenging due to their gregarious nature and the lack of detectable early symptoms. Systemic insecticides are effective means of control, but their use in urban areas is prohibited and resistance can develop. Considering alternative options with minimal environmental impact, the Sterile Insect Technique (SIT) has been explored. Previous research has shown that male RPWs irradiated at 80 Gy or higher achieve full sterility. This study aimed to investigate in laboratory conditions whether RPW sterile males (irradiated at 60 and 80 Gy) could compete sexually with non-irradiate males. Laboratory bio-assays under both no-choice and choice conditions assessed sexual performance in terms of number of matings, mating duration and time elapsed until the first mating. The results confirmed that irradiation does not negatively affect the mating performance of sterile males, demonstrating their ability to compete successfully with non-irradiated males in both experimental setups.

Abstract Background Trichoderma species are able to cause significant changes in the metabolism of host plants, by that means it trigger the plant growth and increasing plant defense to diverse fungal diseases. Trichoderma harzianum has been identified as potential biocontrol agent of many phytopathogenic fungi. Therefore, the aim of this study was to assess in vitro antagonistic activity against three Diplodia isolates utilizing direct and remote confrontations methods. Results The results revealed that T. harzianum inhibited mycelial growth of the three phytopathogenic fungi compared to the untreated control. The percentage of growth inhibition of T. harzianum against Diplodia isolates ranged between 58 and 79% for direct confrontation and between 31 and 46% remote confrontation. Considerable antagonistic abilities of T. harzianum were exhibited against all tested Diplodia isolates. The results of both confrontations showed that the radial growth of the fungal pathogens was statistically significant (P

Abstract Background The tachinid parasitoid, Exorista segregata (Rondani, 1859) (Diptera: Tachinidae) is a polyphagous fly recorded on larvae of lepidopterans. Larvae of the Erebidae, Orgyia trigotephras Boisduval were collected from Northern Tunisia and reared in the laboratory at INRGREF. Larvae were kept individually until emergence of parasitoid’s adults. Results Morphological data including dissected genitalia was used to identify E. segregate as a parasitoid of O. trigotephras larvae. Conclusion The larval parasitoid, E. segregata is recorded from a new host O. trigotephras for the first time in Tunisia. This species could be considered in the programs of biological control of different lepidopterans’ pests in Tunisia and neighboring countries.

Abstract Background The polyphagous tachinid Compsilura concinnata is an endoparasitoid fly recorded as attacking larvae of Lepidoptera and Hymenoptera. Larvae of Orgyia trigotephras [Lepidoptera: Erebidae] were collected from northern Tunisia and reared in the laboratory. Results Adult flies that emerged from these larvae were identified on the basis of morphological description and DNA analysis (PCR) as Compsilura concinnata. Conclusion Compsilura concinnata is recorded here for the first time from Orgyia trigotephras in Tunisia. This species could be of great interest as a potential biological control agent of pests in Tunisia and neighboring countries.