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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]

Peptaibols are non-ribosomal linear peptides naturally produced by a wide variety of fungi and represent the largest group of peptaibiotic molecules produced by Trichoderma species. Trichogin GA IV is an 11-residue lipo peptaibol naturally produced by Trichoderma longibrachiatum. Peptaibols possess the ability to form pores in lipid membranes or perturb their surface, and have been studied as antibiotics or anticancer drugs in human medicine, or as antimicrobial molecules against plant pathogens. When applied to plants, peptaibols may also elicit defense responses. A major drawback to the exploitation and application of peptaibols in agriculture is their poor water solubility. In a previous study, we designed water-soluble Lys-containing Trichogin GA IV analogs, which were able to inhibit the growth of several fungal plant pathogens in vitro. In the present study, we shed light on the mechanism underpinning their efficacy on plants, focusing on six Trichogin GA IV analogs. Our results highlighted peptide hydrophilicity, rather than helix stability, as the major determinant of their activity against B. cinerea infection in tomato leaves. The peptides showed preventive but not curative efficacy against infection, and lack of translaminar activity, with results reproducible on two tomato cultivars, Marmande and Micro-Tom. Reactive oxygen species (ROS) detection analysis in tomato and Arabidopsis , and expression of defense genes in tomato, highlighted a transient and limited impact of the peptides on the plant defense system. The treatment did not result in significant modulation of defense genes or defense priming. The antimicrobial effect thus emerges as the only mechanism behind the plant protection ability exerted by water-soluble Trichogin GA IV analogs, and limited effects on the plant metabolism are expected to occur. [ABSTRACT FROM AUTHOR]

Olive (Olea europaea L.) is an evergreen xerophytic tree characterizing vegetative landscape and historical-cultural identity of the Mediterranean Basin. More than 2600 cultivars constitute the rich genetic patrimony of the species cultivated in approximately 60 countries. As a subtropical species, the olive tree is quite sensitive to low temperatures, and air temperature is the most critical environmental factor limiting olive tree growth and production. In this present review, we explored the detrimental effects caused of low temperatures on olive cultivars, and analyzed the most frequently experimental procedures used to evaluate cold stress. Then, current findings freezing stress physiology and gene are summarized in olive tree, with an emphasis on adaptive mechanisms for cold tolerance. This review might clear the way for new research on adaptive mechanisms for cold acclimation and for improvement of olive growing management. [ABSTRACT FROM AUTHOR]

Fig trees are widely cultivated in the Mediterranean basin area where the fruit is appreciated by consumers for its nutritional characteristics. The taste and quality of fig fruits partially depend on the concentration and composition of soluble carbohydrates, and thereafter on the activity of enzymes and transporters of carbohydrate metabolism. We analysed the expression of 11 key genes of carbohydrate metabolism and of six genes encoding sugar transporters in fruits of two Italian cultivars, Dottato and Brogiotto. Most genes showed the expected expression pattern in the transition from unripe to ripe fruit. However, six out of 11 genes, encoding two sorbitol dehydrogenases, an alkaline/neutral invertase, an acidic invertase, and a hexokinase, and a phosphofructokinase, showed significant differences in transcripts level in unripe and/or ripe fruits between the two genotypes. Three out of six sugar transporter genes, encoding two sucrose transporters and one sorbitol transporter were up regulated in mature fruits of cv. Dottato. Glucose and fructose concentrations were higher than that of sucrose in the fruit of both cultivars. Sorbitol content was higher in Dottato than in Brogiotto fruits. In conclusion, the results suggested that differences in gene expression between the two cultivars do not affect the concentration of sucrose, glucose and fructose in mature fruits, while are likely responsible for the higher content of sorbitol observed in the ripe fruits of the cv. Dottato than in Brogiotto. [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]

Mucins are a family of large glycoproteins that represent the major structural components of the mucus and are encoded by 20 different mucin genes. Mucin expression can be modulated by different stimuli. In this study, we analyzed four mucins (MUC2, MUC3, MUC13, and MUC17) in coculture of Caco‐2/HT29‐MTX cells to demonstrate the variation in gene expression in the presence of antioxidant compounds like chlorogenic acid, epicatechin gallate, and quercetin (apple, tea, and coffee polyphenols, respectively). coculture of Caco‐2/HT29‐MTX cells was treated with polyphenols, and the expression of four mucins was determined by reverse‐transcriptase PCR. In addition, the secretion levels of MUC2 were established by enzyme‐linked immunoassay (ELISA) analysis. The results showed that each polyphenol compound induces different expression patterns of the mucin genes. Statistically significant up‐regulation of MUC17 was observed following incubation with epicatechin gallate and quercetin. ELISA results did not prove any significant differences in protein levels of MUC2 after treatment by the polyphenol compounds. The polyphenols considered in this study may influence mucin secretion and act on diverse salivary substrates to change the barrier properties of mucins for mucus secretion in different ways. The effects of dietary polyphenols on mucin secretion and expression have been studied to some extent, for that reason the present study investigated the use of two human adenocarcinoma cell lines in co‐culture of Caco‐2/HT29‐MTX, as a model to mimic gut epithelium, in order to examine the effect of three dietary plant polyphenols (chlorogenic acid, epicatechin gallate, and quercetin) on the gene expression of four mucins. Our research highlights the insights into the extent to which the polyphenols may influence mucin secretion and act on mucus barrier properties. [ABSTRACT FROM AUTHOR]