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Medicinal mushrooms are very interesting for their pharmacological effects as well as for their nutritional value, antitumor, antiviral, antibacterial activities. Antitumor activities of mushrooms have been extensively investigated due to recent chemotherapeutic application of some drugs derived from natural sources.The aim of this study was the morphological and molecular characterization of nine species of fungi with potential medicinal interest. In particular, we focused our attention on: Bjerkandera adusta (Willd) P. Karst., Ganoderma resinaceum Boud.,Hericium erinaceus (Bull.) Pers., Pleurotus eryngii var elaeoselini Venturella, Zervakis and La Rocca, P. eryngii var. eryngii (DC.) Quél., P. eryng i var. ferulae (Lanzi) Sacc., P. nebrodensis (Inzenga) Quél., P. opuntiae (Durieu & Lév.) Sacc., P. ostreatus (Jacq.) P. Kumm. The basidiomata were collected in Sicily and subsequently were dried and they were stored in the Herbarium SAF of the Department of Agricultural, Food and Forest Sciences (University of Palermo, Italy). The identification was performed by examining the whole basidiomata (cap, gills, stipe, etc.). The microscopic features were observed in water using a Leica microscope DMLB. Basidiospores measurements were based on 50 observations. Nomenclature is referred to Index Fungorum (http://www.indexfungorum.org/ Names/Names.asp). Subsequently to confirm the identification molecular analysis were carried out. The internal transcribed spacer (ITS) region is the primary choice for molecular identification of fungi and the preferred DNA barcoding marker. Total DNA was extracted from dry tissue using the CTAB- based protocol [4]. PCR amplification was carried out with ITS1F/ ITS4 primer pairs targeting the ITS. PCR conditions, were performed as described by Oliveri et al. Obtained PCR products were sequenced in both directions using an ABI PRISM DNA 377 sequencer (Perkin-Elmer, Boston, MA, USA). Nucleotide sequences were compared with sequences of respective reference species retrieved from GenBank. Phylogenetic relationships were inferred by the Minimum Evolution method with 1,000 bootstrap replicates, using the algorithm Kimura-2-parameter. The phylogenetic analysis revealed that all species examined clustered with reference species with an identity > 99%. A particular case is represented by some species of the genus Ganoderma.In fact, this genus includes many species that are diffic lt to characterize both macroscopically and microscopically, with classical examples being G. resinaceum and G. lucidum which may seem identical but which differ for a few imperceptible characters. Therefore, in order to have a clear characterization, it is useful to use molecular analysis and then of Bar-Coding technology, which can be a very useful tool for the characterization of new fungal species. For this purpose, it would be useful, especially for the characterization of fungal species of difficult morphological identification, to analyze, in addition to the ITS1 region, at least one other coding gene sequence, preferably located in genome portion away from the ITS 1. The molecular analysis technology, with particular reference to the conserved genome regions that can be used as a reference for Bar-Coding, is particularly useful, but not alone, in order to classify fungus with very similar morphological characteristics.

Twenty-five tomato plants (Solanum lycopersicum) showing symptoms of viral disease were sampled from different greenhouses in the Ragusa province (Southern Italy) in summer 2015. Plants showed chlorosis on leaves and fruits and deformation and depressed spots of dark colour which later evolved into necrosis (Fig. 1). These symptoms were observed on the entire cluster of fruit making the product unsaleable. Based on these symptoms, samples were analysed for Cucumber mosaic virus, Pepino mosaic virus (PepMV), Potato virus Y (PVY), Tomato mosaic virus and Tomato spotted wilt virus by DAS-ELISA with polyclonal antibodies (Loewe Phytodiagnostica, Germany), and for the emerging Southern tomato virus (STV) by RT-PCR (Candresse et al., 2013). Three of the 25 samples analysed were positive only for PepMV whereas the rest of the samples had mixed infections: fifteen plants were co-infected with PepMV and PVY, and seven with STV, PepMV and PVY. The amplification product (894 bp) obtained from one STV-infected plant was purified using the UltraClean® PCR Clean-Up kit (Mo-Bio, USA) and the consensus nucleotide sequences were determined in both senses using an ABI 3130XL Genetic Analyzer (Life Technologies, USA) and deposited in GenBank under accession number KT948068. The nucleotide identity of the Italian STV isolate was greater than 99% with STV isolates Mexico1 (EF442780), BD-13 (KT634055), CN-12 (KT438549), MS7 (EU413670) and FR (KC333078) from Mexico, Bangladesh, China, USA and France, respectively.

The genetic variation and evolution of Cucumber mosaic virus (CMV) (1) infecting aromatic, medicinal and ornamental plants in Northern Italy were studied by sequence analysis of the movement protein gene and comparison with equivalent sequences of isolates from other countries. Comparison of nonsynonymous and synonymous substitutions at each codon suggested that 30% of amino acid sites were under negative selection and only one was under positive selection. Phylogenetic inference, nucleotide diversity estimation, neutrality tests and genetic differentiation analysis revealed a high nucleotide diversity of CMV in Northern Italy with respect to areas of other countries [1,2] and suggested that long distance migration plays a main role in the evolution and determination of the different genetic structures of this virus. 1. García-Arenal et al., 2000. Virus Res 71:1. 2. Lin H.X. et al., 2004. J Virol 78:6666.

In the Summer of 2012, Erysimum linifolium L. pot plants produced at an ornamental grower in Liguria region (northern Italy), showed unusual virus-like disease of dark mottle and stripes on mauve-purple petals. A virus was mechanically transmitted from symptomatic flowers to several test plant species belonging to Chenopodiaceae and Brassicaceae families. This virus was identified as an isolated of turnip mosaic virus (TuMV) by PAS-ELISA analysis, electron microscopy negatively stained crud extracts and immuno-electron microscopy (IEM) tests. In the naturally infected E. linifolium plants, TuMV occurred alone, since any other viruses either by electron microscopy or mechanical inoculations were detected. By applying RT-PCR a fragment of 862 bp was amplified corresponding to all coat protein (CP). The comparison of CP gene showed no correlations between their genetic variation and geographical origins. The diversity in southern Europe appeared very low, most likely due to the rapid growth of TuMV in relation to trade between different Countries. The consequent exchange of infected propagation material shows that some lineages are adapted to particular crop species, and that recombination is a significant generator of the genetic diversity in populations of this virus. This is the first report of TuMV in E. linifolium worldwide

Inula viscosa L. (Asteraceae) is a well-known perennial medicinal herb that grows wild in the Mediterranean area. Both folk and traditional medicines ascribe several uses to this plant, such as antipyretic, antiseptic, etc. In Spring 2007, almost 40% of I. viscosa plants cultivated at the Herb Garden “Augusto Rinaldi Ceroni “ of Casola Valsenio (Emilia Romagna, Italy) showed chlorotic mosaic on leaves. Symptomatic samples were collected and analysed. No spherical or elongated virus-like particles were observed by transmission electron microscopy in leaf extracts using a leaf dip method. By applying PAS-ELISA technique, Cucumber mosaic virus alone was detected in all symptomatic plants (more than 20) tested, using a polyclonal antiserum (PVAS 30, American Type Culture Collection, Manassas, VA, USA). CMV from I. viscosa leaves was mechanically transmitted to Nicotiana tabacum L. “Samsun”, which developed systemic mosaic symptoms. To confirm the association of CMV with the diseased plants, total RNA was extracted from the same samples (RNeasy Plant Mini Kit; Qiagen, Hilden, Germany) and analyzed by RT-PCR using CMV-specific primers MP+ and MP- (Lin et al., 2004). The expected 842 bp fragment was amplified only from samples of symptomatic tissue while no amplification product was observed when water or healthy plants were used as a template. RT-PCR products were cloned and sequenced. The sequence obtained (GenBank Accession No. EU432181) had 99% identity with CMV-TN (GenBank Accession No. AB176847) which induces tomato necrosis disease, and several other isolates of subgroup II. To our knowledge, this is the first report of CMV infecting I. viscosa and it adds a new host to the list of more than 1,000 species infected by this virus.