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An aberrant specimen of Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) also known as red palm weevil (RPW), the most economically important insect pest of palms in the world, was found among a batch of conspecifics reared for research purposes. A morphological analysis of this weevil revealed the presence of nematodes associated with a structured cuticle defect of the thorax. These nematodes were not able to be cultured, but were characterized by molecular analysis using 28S and 18S ribosomal DNA and shown to belong to the family Panagrolaimidae (Rhabditida), within a clade of Panagrellus. While most nematodes in the insect were juveniles, a single male adult was partially characterized by light microscopy. Morphometrics showed similarities to a species described from Germany. Excluding the entomopathogenic nematodes (EPN), only five other genera of entomophilic or saprophytic rhabditid nematodes are associated with this weevil. This is the first report of panagrolaimid nematodes associated with this invasive pest. Possible mechanisms of nematode-insect association are discussed. [ABSTRACT FROM AUTHOR]

Aclees sp. cf. foveatus (Coleoptera: Curculionidae) is spreading in Central Italy, causing severe infestation on fig trees. There are very few information for this pest and no natural enemy is reported. Here, we report the first recovery of a natural enemy associated with this invasive weevil, a strain of the entomopathogenic fungus Beauveria bassiana. The potential use of entomopathogenic fungi and nematodes as biocontrol agents was tested against adults in laboratory trials. In agree with the detection in nature, only treatments with B. bassiana were able to control the insects. This result opens new frontiers for the environmental friendly control strategies against this weevil. [ABSTRACT FROM AUTHOR]

Rhynchophorus ferrugineus is considered the worst pest of palm species, and few natural enemies are reported for this parasite in its area of origin. Here, we report the first recovery of the entomopathogenic fungus Metarhizium pingshaense associated with R. ferrugineus from Vietnam. The morphological, biochemical, and toxicological features of this strain were studied and compared with those of another Metarhizium strain associated with this weevil in Sicily (Italy), an area of recent introduction. The potential use of these fungi as biocontrol agents was tested against adult insects in laboratory trials and a similar mortality rate was found. Both strains were able to produce toxins and cuticle-degrading proteases, but they showed dissimilar enzymatic and toxicological profiles, suggesting a different virulence activity. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent years, a new pest, the black weevil Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae) native to Asia, has been recorded in France and Italy. Aclees taiwanensis larvae cause the rapid death of the fig tree (Ficus carica), digging alimentation galleries in the trunk and surface roots, compromising the phloem flux. To date, no specific EU regulation has been applied to prevent the A. taiwanensis spread, and we can reasonably expect a rapid diffusion of this pest all over the Mediterranean area where F. carica is widespread. This paper updates the known distribution of this species in Southern Europe, using a citizen science approach, and describes, under laboratory and field conditions, its main biological traits. Ficus carica L. is one of the earliest cultivated fruit trees, and figs are a typical fruit of the Mediterranean diet and traditional medicine as well. In recent years, a new pest, the black weevil Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae) native to Asia, has been recorded in France and Italy. Aclees taiwanensis causes the rapid death of the fig tree by its larvae that dig alimentation galleries in the trunk and surface roots, compromising the phloem flux. In Italy, from 2005, the year of the first detection of A. taiwanensis, the fig production has nearly halved, decreasing from 20.09 t to 10.65 t. To date, no specific EU regulation has been applied to prevent the A. taiwanensis spread, and we can reasonably expect a rapid diffusion of this pest all over the Mediterranean area. To avoid the loss of the Mediterranean fig orchards, effective strategies to detect and control the black weevil are required. Such strategies need a detailed knowledge of A. taiwanensis distribution, biology, and physiology. This paper updates the known distribution of this species in Southern Europe, using a citizen science approach, and describes, under laboratory and field conditions, its main biological traits. [ABSTRACT FROM AUTHOR]

Background: Popillia japonica Newman is a scarab beetle native to Japan that is considered a serious pest outside its native range. It can feed on more than 400 host plants and spread about 10 km per year in invaded territories, therefore it is considered the second most important quarantine pest in Europe. Both chemical and biological insecticides have been used for control, with variable results. Despite ongoing efforts, P. japonica remains a threat in invaded countries, and it is necessary to test more effective and sustainable solutions in the context of integrated pest management. Here we present a study on long-lasting insecticide-treated nets (LLINs) assembled in semiochemical-baited attract-and-kill devices (A&Ks) as a means to control adults of P. japonica with low environmental impact. This study complements previous ones in which we first evaluated the effectiveness of the LLINs in the laboratory and then tested both effectiveness and duration in field-exposed A&Ks against P. japonica. In the present work we compared the effectiveness of three different densities of A&Ks per hectare in areas where the population of P. japonica was numerically homogeneous., Results: The different densities of A&K (1, 2, 4 A&Ks per ha) resulted in an overall reduction of the population of P. japonica by about two thirds in comparison to the control area., Conclusions: This study suggests that the use of one A&K per hectare, requiring minimal management effort, is an effective ratio for reducing local populations of P. japonica. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Background: The olive fruit fly (OFF), Bactrocera oleae (Rossi), is the main insect pest of olive trees worldwide. Legislation limits to the use of some synthetic larvicidal insecticides is leading to the development of new control options for preventive control of adult flies. In the present study, the biological activity of four short-chain aliphatic aldehydes, namely hexanal, (E)-2-hexenal, heptanal and (E)-2-heptenal, previously reported as repellents to the OFF adults was investigated., Results: Electroantennography (EAG) recordings showed that antennae of OFF males and females are able to perceive the test compounds in a wide range of doses. In field trapping experiments, reservoir-type polypropylene (PP) membrane dispensers loaded with individual compounds did not elicit a significant attraction of OFF males and females. On the contrary, a significant reduction of male catches was noticed when sex pheromone dispensers and PP membrane dispensers, loaded with one of the test compounds, were applied on the same white sticky traps ≈20 cm apart. Likewise, male and female catches in yellow sticky traps baited with ammonium carbonate (AC) dispensers as food attractant were significantly reduced by the presence of PP membrane dispensers of individual aliphatic aldehydes on the same traps. In small plots control trials, solid formulations of the four aldehydes into a bentonite clay support induced a significant reduction of the OFF active infestation mainly when C 6 and C 7 aldehyde-activated bentonites were used., Conclusion: Short-chain aliphatic aldehydes showed inhibitory effects on sex pheromone and food attractant-mediated attraction of OFF. Results of field trials suggest potential of short-chain aliphatic aldehydes to develop new semiochemical-based OFF control options. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)