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Botryosphaeria dieback is a widespread grapevine trunk disease caused by species of fungi within the family Botryosphaeriaceae. Symptoms of the disease include bud necrosis, leaf chlorosis, vascular discoloration of the wood, cankers and dieback. In 2013 typical symptoms of Botryosphaeria dieback was observed in Western Sicily and four species associated with the syndrome were isolated and identified as Diplodia seriata, Lasiodiplodia mediterranea, Neofusicoccum parvum and Neofusicoccum vitifusiforme. In order to fulfill Koch’s postulates, pathogenicity tests of eighteen isolates were performed on two-year grapevine cuttings of cv. Inzolia. Six months after inoculation all the Botryosphaeriaceae isolates induced vascular discoloration of the wood with differences between the species and within the isolates. D. seriata B22 was the most virulent isolate showing the longest mean lesion length, significantly different from those caused by any other Botryosphaeriaceae isolates. The control of Botryosphaeria dieback is difficult and integrate pest management is necessary to reduce disease incidence. In recent years, the use of biocontrol agents is becoming a valuable strategy for the control of plant diseases. Bacillus amyloliquefaciens AG1, isolated from grapevine wood tissue, has been reported to be effective against some fungi associates to grapevine trunk disease. In this study, the antimicrobial activity of B. amyloliquefaciens AG1 was evaluated by well diffusion assay against Botryosphaeriaceae fungi associated to Botryosphaeria dieback in Western Sicily. Cell-free supernatant of B. amyloliquefaciens AG1 showed significant antifungal activity inhibiting fungal growth of all tested isolates.

Cu2O/TiO2 nanotubes heterojunctions were fabricated by electrochemical deposition of cuprous oxide on TiO2 nanotubes arrays grown by anodizing. X-ray diffraction and Raman Spectroscopy analysis allows for identification of Cu2O, whose morphological features were studied by Scanning Electron Microscopy as a function of the charge circulated during the electrodeposition step. Photoelectrochemical measurements in aqueous solutions evidenced a red shift of the light absorption threshold of TiO2 nanotubes due to the presence of cuprous oxide even for very low circulated charges, while electrochemical impedance measurements proved a significant reduction of the electrode impedance due the presence of Cu2O. Photoelectrochemical measurements in non aqueous solutions allow to reduce reverse bias across the junction and to measure stationary cathodic photocurrent, thus confirming the formation of p-type Cu2O inside the nanotubes.

Thermal oxidation of titaniumwas carried out at 350◦C, 450◦C, and 550◦C for 2 h or 12 h.X-rayDiffraction and Raman Spectroscopy suggest that the thermal oxides are scarcely crystallinewhen the annealing temperature is low, while both anatase and rutile are present for high annealing temperature and time. Photoelectrochemical measurements allowed estimation of a bandgap decreasing from 3.35 eV to 3.15 eV with increasing annealing temperature. The impedance spectra confirmed the formation of n-type semiconductors, with an impedance strongly decreasing on going from a reverse bias toward a forward bias regime. TiO2 nanotubes grown by anodizing Ti in NH4F and water containing ethylene glycol solution were annealed at different temperature and for different times. X-ray Diffraction and Raman Spectroscopy proved that rutile is present at the barrier layer beneath the tubular array, while the tubes are mainly constituted by anatase. The incident photon to current conversion efficiency increased by increasing the annealing temperature and time. The impedance spectra recorded under reverse bias regime for thermal planar oxides and for annealed TiO2 NTs are almost coincident, confirming that the predominant contribution arises from the barrier layer beneath the tubular array. Only under forward regime do the tube walls contribute to the measured impedance.

During a multi-year study on the life cycle of Plasmopara viticola to assess the typical epidemiology of downy mildew on grapevine (Vitis vinifera) in west Sicily (Italy), several leaves on which the downy mildew had collapsed were found and observed in a vineyard located in Marsala, in Trapani Province. An antagonistic fungus was isolated from these leaves and named A20; through its morphology, it was identified as a hyphomycete belonging to the genus Acremonium. The antagonism of A20 against the asexual and sexual spores of P. viticola, as well as endophytic nature of the genus Acremonium in V. vinifera were confirmed by further studies which have been carried out over the past decade. In order to inform winegrowers about this new future possibility for the biological control of grapevine downy mildew, this chapter reports the results of investigations on the interaction between the endophytic fungus A20, the presence of endophytic fungi in the grapevine and downy mildew

The dynamics of sporulation and zoosporogenesis of Phytophthora infestans in a naturally infected crop of potato cv. Maris Bard and on potted plants of the same cultivar infected artificially with the same fungus are described. Development of sporangiophores and sporangia was synchronous after induction. Migration of several nuclei from the sporangiophore into the sporangium initial was followed by nuclear division, then by degeneration of a proportion of the nuclei. Sporangia then became deciduous, developed papillae and became able to release zoospores in rapid succession. When infected leaves were detached and transferred from the field to moist Petri dishes, sporulation was at first synchronous then sequential; sporangiophores were longer and lateral branches more numerous than in vivo. The number of nuclei in mature sporangia was greater in vitro than in vivo.

Basidiomata of a mushroom macroscopically recognised as Pleurotus cystidosus sensu latu were collected on the trunks of three tropical ornamental trees such as Broussonetia papyrifera, Yucca elephantipes, and Paulownia tomentosa in the Parco d’Orleans, an urban park in the town of Palermo (Sicily, Italy). All the plants showed cavities and white rot symptoms at the base of the trunks. Macro- and microscopic observations on both collected basidiomata and isolated colonies, as well as molecular analysis, allowed identifying the collected basidiomata as Pleurotus fuscosquamulosus and its anamorph as Antromycopsis fuscosquamulosus. These species belong to the subgenus Coremiopleurotus that includes different species producing synnematoid fructifications. The positive reaction of the colonies to the syringaldazine and the artificial inoculation tests on wood blocks of B. papyrifera confirmed its white wood rotting activity. To our knowledge, this is the first report of occurring of P. fuscosquamulosus in Italy on three new tropical plant hosts.