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ABSTRACTInappropriate land preparation before vineyard establishment can lead to soil degradation and vine health issues, with consequent reductions in the quantity and quality of the grapes. In the present short-term trial, the effects of dry mulching, green manure and compost treatments were evaluated as restoration strategies to enhance soil functionality in degraded vineyard areas at two Tuscan farms that had been under organic management for different lengths of time. Soil nematode community, soil physical and chemical properties were monitored as indicators of soil quality. The restoration treatments scarcely affected soil chemical or physical qualities; only the compost application increased soil total organic carbon (TOC). Bacterial feeder nematodes increased under dry mulching in response to the organic carbon inputs on the farm in conversion. Plant-parasitic nematodes decreased only after the first year of the restoration treatments and predators decreased during all 3 years. Nematode indicators showed only a few differences between the different management regimes; the diversity weighted abundance expressed as biomass indicated that the restoration practices sometimes represented a disturbing factor in ecosystem services regulation. The abundance of nematode taxa was differently affected by soil physico-chemical properties. On the farm that had been managed organically for longer, the higher proportion of large sized stable aggregates and greater soil porosity benefitted large nematodes such as predators, while the higher moisture levels were unfavourable for some plant-parasitic nematodes. However, on the farm still in conversion, increases in TOC and C/N ratio values were associated with a reduction in plant-parasitic nematodes.

Rhabditis (Rhabditella) axeiis a free-living, pseudoparasitic, necromenic, and parasitic nematode, depending on the host. This species feeds mainly on bacteria present in decaying organic matter, soil, and other substrates; however, in its parasitic form, it can colonize some species of snails. Moreover, the presence of R. axeihas also been detected in birds and mammals, including humans.

Saffron is one of the most precious spices in the world. It is derived from the dried stigmas of the Crocus sativusL. flowers. This plant is triploid sterile and propagated by corms. As a subterranean organ, the corm can come into contact with different nematodes. In this contribution Bursaphelenchus fungivoruswas reported for the first time in Italy. It was found associated with C. sativuscorms and characterized based on morphological and morphometrical characteristics for this species. The identification was confirmed using molecular analyses. Moreover, a review of nematodes associated with C. sativusworldwide is also provided.

An aberrant specimen of Rhynchophorus ferrugineus(Coleoptera: Dryophthoridae) also known as red palm weevil (RPW), the most economically important insect pest of palms in the world, was found among a batch of conspecifics reared for research purposes. A morphological analysis of this weevil revealed the presence of nematodes associated with a structured cuticle defect of the thorax. These nematodes were not able to be cultured, but were characterized by molecular analysis using 28S and 18S ribosomal DNA and shown to belong to the family Panagrolaimidae (Rhabditida), within a clade of Panagrellus. While most nematodes in the insect were juveniles, a single male adult was partially characterized by light microscopy. Morphometrics showed similarities to a species described from Germany. Excluding the entomopathogenic nematodes (EPN), only five other genera of entomophilic or saprophytic rhabditid nematodes are associated with this weevil. This is the first report of panagrolaimid nematodes associated with this invasive pest. Possible mechanisms of nematode-insect association are discussed.

Montecristo Island is an integral natural reserve of the Tuscan Archipelago National Park (Central Italy), characterized by a peculiar assemblage of flora and fauna, with several endemic taxa, and also with a high number of alien species. During a soil survey, we found an alien Oscheius tipulaeLam & Webster, 1971 isolate, phylogenetically close to others from South America. In this article, we examined the possible pathways of introduction of this nematode. Because of the high number of alien plants in this protected area and the low desiccation survival ability of O. tipulae, we hypothesized that the presence of this alien nematode isolate may be related to the soil of introduced plants, although historical association with plant-associated invertebrates is also possible. Further studies with more populations and marker molecules are necessary to investigate the distribution of O. tipulaeand the possible impact on this natural reserve.