The black-banded oak borer, Coraebus florentinus, is an emerging pest of oak trees in the western Mediterranean region. Larvae of the insect are xylophagous and progressively excavate an annular gallery that interrupts sap flow, resulting in the death of the attacked branches. Until now, limited information has been available regarding the ecological interactions between C. florentinus and the main plant pathogenic fungi involved in the etiology of oak decline. Knowledge of these interactions is important in understanding their impact in natural ecosystems and developing appropriate management strategies. Therefore, in this study, we characterized the fungal communities occurring in the exoskeleton of adults and larvae of C. florentinus and associated with the necrotic wood tissues surrounding the branch galleries of declining oak trees. A total of 29 fungal species were identified based on DNA sequence data and morphological features, of which 14 were from symptomatic woody tissues, six from insect exoskeleton, and nine from both insects and symptomatic wood tissues. The most frequent fungal species, Cryphonectria naterciae (15.9% of isolates), Dothiorella iberica (11.3%), and Diplodia corticola (9.9%), were isolated from both insect and gallery systems. All three species are well-known oak pathogens and are reported here, for the first time, to be associated with C. florentinus. At the same time, 89.6% of the fungal taxa were isolated from one or two sites, highlighting the site-dependence of fungal community assemblages.

The rapid growth and environmental adaptability of Eucalyptus species has favored their global cultivation for pulpwood production. On the island of Sardinia, Italy, eucalypt plantations were established in the 20 th century primarily in areas reclaimed from marshland, but the trees are now grown all over the island as ornamentals or windbreaks, and for timber, pulp and honey production. In recent years, an unusual decline and mortality of unknown etiology has been observed in Eucalyptus camaldulensis (river red gum) plantations throughout the island. Given the ecological and economic importance of eucalypt ecosystems in Sardinia, a survey was carried out in 2013 to determine which insect pests and fungal pathogens are directly involved in these phenomena. Field surveys throughout the island revealed severe infestations with the red gum lerp psyllid (Glycaspis brimblecombei) at all 12 surveyed sites, with the greatest numbers of pre-imaginal stages and adults occurring between May and July. The adult population reached its peak in July, followed 2 months later by the peak population of its specific parasitoid, Psyllaephagus bliteus. Symptoms of leaf chlorosis, crown thinning, shoot and branch dieback, sunken cankers, epicormic shoots and exudations of kino gum were also observed at the 12 field sites. Symptomatic woody samples yielded fungal isolates representing three distinct families: Botryosphaeriaceae, Diaporthaceae and Valsaceae. Morphological and DNA sequence data revealed seven distinct fungal species, namely Diaporthe foeniculina, Neofusicoccum australe, N. luteum, N. mediterraneum, N. parvum, N. vitifusiforme and Valsa fabianae. Two putative new species of Cytospora were also identified. Neofusicoccum australe was the only species recovered from all 12 sites, with isolation frequencies of 51-95%. Pathogenicity trials revealed that all Neofusicoccum species except N. vitifusiforme are directly involved in the etiology of the observed decline in the E. camaldulensis population on Sardinia.

I.-Preliminary results on the spatio-temporal variability of Glycaspis brimblecombei (Hemiptera Psyllidae) populations from a three-year monitoring program in Sardinia (Italy). The red gum lerp psyllid Glycaspis brimblecombei is an invasive insect species worldwide. Prolonged attacks by this psyllid may cause both direct and indirect damages to Eucalyptus trees, such as plant weakening, developmental reductions and phylloptosis, resulting in death within 2-3 years. After the first report in Campania (Italy) in 2010 on Eucalyptus camaldulensis trees, it quickly spread to all surrounding central-southern regions of Italy. In Sardinia, G. brimblecombei was first recorded in 2011, and is currently found throughout the island. From 2013 to 2015 a monitoring program was carried out in 11 locations throughout Sardinia in order to estimate the density pattern of both its adults and preimaginal stages, as well as the general population trend of G. brimblecombei over the years. An analysis of G. brimblecombei population abundance showed an almost stable level of infestation over the years, and a seasonal pattern with a population peak in the summer. However, an earlier peak of population abundance was detected in 2015 compared to the previous years. A spatial heterogeneity of the level of infestation was observed throughout the island, highlighting the potential effects of environmental conditions in regulating the populations of both G. brimblecombei and its natural enemies.

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The study shows the results of an inventory of place names connected to Arbutus unedo L., a Mediterranean species, widespread throughout Sardinia. The main aim was to compare the past distribution of place names, referring to the strawberry tree, to the current distribution of the species on the island. In addition, we investigated the meaning and the diversity of these local place names in the various communities. The result was a collection of 432 phyto-toponyms. 248 of them were used for an analysis of their distribution in the habitats, indicated on the Map of the Nature System in Sardinia, defined on the basis of the current vegetation typology. The persistence of the species in the various habitats was either confirmed or negated with in site investigations and interviews. 47.5% of municipalities have place names related to the strawberry tree. Of the 248 phyto-toponyms, 127 fall in the habitats where the species currently persists proving a correspondence between their regional distribution and the current distribution of the species. The remaining 121 phyto-toponyms fall in habitats where the strawberry tree is currently absent. Most of them are found in man-made habitats where man has transformed the forest cover which previously included the strawberry tree. This study also contributes to promoting and conserving the linguistic heritage of local communities.