In September 2016, a survey conducted in the Circeo National Park revealed an outbreak and serious damage caused by the black twig borer (Xylosandrus compactus) and its associated fungi in the Mediterranean maquis. Among the affected hosts, Quercus ilex, Viburnum tinus, Ruscus aculeatus, Pistacia lentiscus, Laurus nobilis and Ceratonia siliqua, showed flagging and wilting of branches and, in younger individuals, the death of the whole plant occurred. In total, 18 different fungal taxa were found associated with the insect. These included Ambrosiella xylebori, Geosmithia pallida, Fusarium spp., Epicoccum nigrum and Bionectria sp. This is the first report in Europe of X. compactus and associated ambrosia fungi in a natural environment.

A study on seasonal abundance of Auchenorrhyncha species and their infectivity by Xylella fastidiosa in the Apulia region of Italy was conducted to identify ideal periods for monitoring and adoption of potential control measures against insect vectors. Adult populations of Auchenorrhyncha species were monitored monthly over a 2-yr period from five olive groves. A total of 15 species were captured, identified, and tested for presence of X. fastidiosa by polymerase chain reaction (PCR). For three species, Philaenus spumarius L., Neophilaenus campestris (Fallèn), and Euscelis lineolatus Brullé, positive reactions to X. fastidiosa were obtained, on average, in 16.3, 15.9 and 18.4% of adult insects, respectively. Philaneous spumarius was the dominant species (39.8% of total Auchenorrhyncha captured) with the highest adult abundance in summer months. Adult P. spumarius and N. campestris were first detected between March and May in both years, and all insects tested during these periods (year 1: n = 42, year 2: n = 132) gave negative reactions to X. fastidiosa by PCR. Similarly, first adults of E. lineolatus that appeared from October to November (year 1: n = 20, year 2: n = 15) tested negative for presence of X. fastidiosa Given the lack of transstadial and transovarial transmission of X. fastidiosa and considering that P. spumarius is univoltine, control measures against nymphal stages of P. spumarius should be investigated as means of population suppression to reduce spread of X. fastidiosa in olive groves.

Ambrosia beetles exhibit broad host ranges but a narrow preference based on the condition of the host. Tissues infected by pathogens or containing ethanol can facilitate attacks by ambrosia beetles, although it still remains unclear how these factors interact. The present study aimed to examine how (i) chestnut logs infected with the fungal pathogen Cryphonectria parasitica and treated with ethanol (i.e. baited with ethanol lure, soaked in ethanol or untreated) and (ii) hornbeam logs soaked in different ethanol concentrations (3–12.5%) affect host selection and colonization success of ambrosia beetles. Ethanol‐soaked logs were more attractive to Anisandrus dispar than ethanol‐baited logs or untreated logs, although this difference was more evident in uninfected than infected logs. Increasing ethanol concentration in host tissues was differentially attractive to Xyleborinus saxesenii and Xylosandrus germanus. A nonlinear relationship was also documented between ethanol concentration and emergence of X. germanus adults. Overall, the results obtained suggest that the presence of C. parasitica in chestnut logs can affect host selection in ambrosia beetles. In addition, the ethanol concentration in tree tissues affects host selection and colonization success, although the effect varies depending on the beetle species. This contrasting response could be a niche‐partitioning mechanism based on ethanol within host tissues.

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Chestnut (Castanea spp.) is a very important crop in the Monti Cimini area (Viterbo, Italy) which is seriously infested with the key pest, chestnut gall wasp Dryocosmus kuriphilus (Speranza et al., 2009). In May 2009 such seriously infested chestnut plants in the Monti Cimini area were found with necrotic leaves and galls. Lesions on leaves were irregular and variable in size, lemon green to amber in colour with green margins. Initially, galls were olive green then became dark brown. Inside the galls larvae of chestnut gall wasp were dead. Tissue from the edge of lesions was surface-sterilized using 1% sodium hypochlorite, rinsed in sterile distilled water and aseptically cut in 5-10 pieces not exceeding 5 · 5 mm, plated on potato dextrose agar (PDA) in Petri dishes containing an antibiotic solution (0AE2% streptomycin sulphate) and incubated at 20 ± 3°C. Light brown fungal colonies were observed after 1 week close to the tissue and numerous orange slimy masses of conidia were observed on the culture surface. The colonies were regular in outline with a clear and thinner margin. Conidia were oval to oblong, sometimes slightly obovoid, straight or curved and measured 5AE5-8AE0 lm · 2AE0-3AE0 lm (mean = 6AE8 · 2AE5 lm, n = 210).The fungus was identified at Centraalbureau voor Schimmelcultures (CBS, Utrecht, The Netherlands) as an undescribed species from the genus Gnomoniopsis. Identification was based on both DNA sequencing (ribosomal ITS) and morphology