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An economically important pest of Ficus carica L. is causing severe infestations in many fig nurseries and orchards in Italy. Belonging to the genus Aclees spp. (Coleoptera Curculionidae), this Asiatic species was accidentally introduced in Europe about 15 years ago, in a Tuscan nursery. Originally identified as Aclees cribratus Gyllenhal, it has been then reported as Aclees sp.cf. foveatus Voss and, more recently, identified as Aclees taiwanensis Kono. A serious damage to fig plants is caused mainly by the larvae, which drill tunnels into the wood and by adults that feed on buds, leaves and young fruits. The present survey applies molecular genetics techniques to reconstruct the genetic profile of the species. To this purpose, the partial sequence of the 18S rRNA gene and the hypervariable region ITS2 of the ribosomal cistron were used as molecular markers for specimens of A. taiwanensis collected in Italy and Aclees hirayamai Kono from Philippines. The analysis of the partial sequences of the 18S rRNA allowed the distinction of two haplotypes for each insect, except for a sample from Philippines, for which one haplotype does exist. The use of the ITS2 hypervariable region highlighted the existence of only one haplotype in the Italian accessions. Only in the sample collected in Lucca (2LU) two haplotypes were highlighted in ITS2. These results are discussed with the occurrence of A. taiwanensis in Italy. [ABSTRACT FROM AUTHOR]

In the present study we performed a transcriptional analysis in order to evaluate changes in gene expression induced by exploration in prolonged times. The analysis was carried out 3, 10 and 20 days after exploration. We analyzed the modulation of the expression levels of Pfn2, Casp3, Pdrg1, Pea15, Ywhaz genes which previously were found not modulated 2 days after exploration. Our data show that the expression of Pfn2, Casp3, Pdrg1, Pea15, Ywhaz genes was modulated at 10 or 20 days. The transcript, whose expression had been evaluated with the qRT-PCR, code for proteins which belong to the following functional categories: synaptic modulation, apoptosis, signal transduction. It is interesting to note that the modulation of the expression of these genes was evident some days after environmental exploration, and not previously at 2 days after conditioning as occurred after contextual fear conditioning (CFC). Hence it is possible to hypothesize that the spatial memory processes require a longer period of elaboration than the emotional ones, fundamental for the survival of the species. [ABSTRACT FROM AUTHOR]

Verticillium spp., including V. nonalfalfae and V. dahliae, are known vascular wilt pathogens of the invasive Ailanthus altissima (tree-of-heaven) in the United States and in Europe. Herein we provide evidence of the presence of a previously unreported wilt disease of A. altissima in Tuscany (Central Italy). Several isolates were collected from two locations and identified as V. dahliae, based on microscopical features of conidiophores, conidia and microsclerotia. Genomic DNA was extracted from the mycelium, the ITS region was amplified and the sequence was deposited in GenBank as VdGL16 (accession no. MK474459). BLASTn analysis showed 100% similarity with V. dahliae. To confirm pathogenicity of VdGL16, inoculations of Ailanthus seedlings were performed with the root dipping technique whereas mature trees were steminoculated. All inoculated seedlings exhibited wilt symptoms after 20 days, while mature Ailanthus trees showed wilting and dieback after six months. The pathogen was easily re-isolated from seedlings and re-identified as V. dahliae, thus satisfying Koch's postulates. Results from intraspecific resistance screening of nine seed sources from across Italy revealed that Ailanthus provenances from all the six sampled regions were susceptible to V. dahliae. Stem inoculated adult plants exhibited abundant production of epicormic sprouts along the stem within six months, and most of these sprouts wilted following initial dieback of the main stem; furthermore, sprouting from the crown was intense. Petioles and rachises tissues of leaves fallen from infected trees were a good source for re-isolation of the pathogen; we proved that such petioles and rachises can effectively transfer the fungus to healthy Ailanthus seedlings via root infections. Host-specificity of the V. dahliae isolate VdGL16 was also determined on 40 non-target species/varieties/cultivars. The isolate caused disease in herbaceous species belonging to five botanical families: Asteraceae, Lamiaceae, Leguminoseae, Linaceae and Solanaceae. Given the difficulties in countering Ailanthus invasion with mechanical and chemical methods, the biological control using Verticillium may provide an efficient, low cost and sustainable control of this invasive species. [ABSTRACT FROM AUTHOR]