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Rhabditis (Rhabditella) axei is 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. axei has also been detected in birds and mammals, including humans. In 2021–2023, during monitoring of the palm borer Paysandisia archon in Central Italy, R. axei emerged from dead larvae of this alien invasive moth and was extracted from palm fibres of Trachycarpus fortunei in three independent sites. The nematode was identified by morphological and morphometric analyses. Molecular analyses using SSU and LSU gene fragments were used to confirm the identification and to perform Bayesian reconstruction of the phylogeny. Each sampling site showed a unique haplotype. Concerning the pathogenicity of this nematode against insects, the test performed on Galleria mellonella larvae did not show any entomopathogenic effect. This is the first time that R. axei was found associated with P. archon, and this recurrent association was discussed. [ABSTRACT FROM AUTHOR]

Saffron is one of the most precious spices in the world. It is derived from the dried stigmas of the Crocus sativus L. 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 fungivorus was reported for the first time in Italy. It was found associated with C. sativus corms 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. sativus worldwide is also provided. [ABSTRACT FROM AUTHOR]

Olive cultivation is of great economic, ecological, and cultural interest in Italy, as well as in the rest of the Mediterranean basin. Among the pests of olive trees, several groups of insects, mites, and nematodes have been reported. Phytoparasitic nematodes especially of the genera Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Tylenchulus, Rotylenchulus, and Heterodera have usually been extracted from roots and soil around trees. On the other hand, no information is available concerning nematodes directly associated with the wood. At the end of September 2018, in a high-density cultivated olive grove in Tuscany (central Italy), several olive trees with decline symptoms were observed. Three Bursaphelenchus species, B. fungivorus, B. minutus, and B. sexdentati were extracted from the wood of one dead tree. Even though these species had already been reported in Italy, these findings were the first ones recorded in olive wood. Moreover, another undescribed Bursaphelenchus species was found associated with the bark beetle Hylesinus fraxini collected from olive trunks and branches. Further research is needed to investigate the role of insects and Bursaphelenchus spp. in the decline processes of olive trees. [ABSTRACT FROM AUTHOR]

Summary: A new species of Bursaphelenchus , extracted from unprocessed logs of Milicia excelsa from Cameroon and arriving in the port of Leghorn, Tuscany, Central Italy, is described. Bursaphelenchus irokophilus n. sp. is based upon morphological and molecular characters and is characterised by the two-lined lateral field, mitten-shaped spicule possessing cucullus and well-developed and slightly dorsally curved condylus with narrowly rounded tip, female vulva with side flap, and long, smoothly tapering and strongly ventrally recurved female tail. The new species belongs to the abietinus -group and is similar to, but distinguished from, B. abietinus and B. rainulfi by the position of secretory-excretory pore, longer and slender female tail and some morphometric values. In addition, the phylogeny based on SSU and D2-D3 LSU regions shows that this species belongs to the abietinus -group, the relationship among the species of this group being discussed. [ABSTRACT FROM AUTHOR]

Pest control in chestnut orchards is mainly achieved by chemicals, but there is growing focus on the potential use of biological control agents. The larval susceptibility of the chestnut weevil Curculio elephas L. (Coleoptera: Curculionidae) to different strains/species of entomopathogenic fungi and nematodes was evaluated in laboratory by soil cup bioassays. In the experiments with fungi, a wild strain of Metarhizium anisopliae caused the highest larval mortality (about 90%) compared with a commercial and a wild strain of Beauveria bassiana (80% and 77% respectively). Regarding nematodes, the commercial strain of Heterorhabditis bacteriophora was more effective in the control of chestnut larvae (77% insect mortality) than Steinernema carpocapsae (43%). [ABSTRACT FROM AUTHOR]

A new phoretic association betweenBursaphelenchus minutusand the bark beetleOrthotomicus erosuscollected onPinus pineais described for the first time. Nematode identification was based on morphological observation and biometric measurements of males and females. Moreover,B. minutuswas characterized by ITS sequences and RFLP profile. [ABSTRACT FROM PUBLISHER]

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 tipulae Lam &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. tipulae and the possible impact on this natural reserve. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In sweet chestnut cultivation, important ecosystem in Europe, the moderate sheep grazing practice may have some beneficial effects in organic farming. Its impact, on soil fertility, soil nematode community and level of fruit infested by tortricids and curculionids was evaluated in a case of study in Tuscany (Central Italy). An organic farm with sheep grazing system (SG) based on long-term field application was compared with an adjacent organic farm with poultry manure system (PM). In both managements, no treatment to control pests and diseases was applied and 0.19 kg /plant of nitrogen were distributed. SG increased twice the amount of organic C, total N and available P than PM. Moreover, the salinity effect of uric acid significantly increased the pH values in SG (from 5.0 to 6.2). The greatest accumulation of organic matter under SG provided stability in nematode community structure and the plant parasitic nematodes decreased. The analysis on the nematodes emerged from Galleria mellonella larvae, revealed that the abundance of native entomopathogenic nematodes was low and not effective to control insect pests. The sheep demonstrated to be the effective predators of tortricid and weevil larvae and in November, the total infestation was significantly lower in SG (34.3%) than PM (54.3%). [ABSTRACT FROM AUTHOR]

Aclees sp. cf. foveatus (Coleoptera: Curculionidae) is spreading in Central Italy, causing severe infestation on fig trees. There are very few information for this pest and no natural enemy is reported. Here, we report the first recovery of a natural enemy associated with this invasive weevil, a strain of the entomopathogenic fungus Beauveria bassiana. The potential use of entomopathogenic fungi and nematodes as biocontrol agents was tested against adults in laboratory trials. In agree with the detection in nature, only treatments with B. bassiana were able to control the insects. This result opens new frontiers for the environmental friendly control strategies against this weevil. [ABSTRACT FROM AUTHOR]

Biological invasions are a global threat to biodiversity. Since the spread of invasive alien plants may have many impacts, an integrated approach, assessing effects across various ecosystem components, is needed for a correct understanding of the invasion process and its consequences. The nitrogen-fixing tree Robinia pseudoacacia (black locust) is a major invasive species worldwide and is used in forestry production. While its effects on plant communities and soils are well known, there have been few studies on soil fauna and microbes. We investigated the impacts of the tree on several ecosystem components, using a multi-trophic approach to combine evidence of soil chemical properties and soil microbial, nematode, microarthropod and plant communities. We sampled soil and vegetation in managed forests, comparing those dominated by black locust with native deciduous oak stands. We found qualitative and quantitative changes in all components analysed, such as the well-known soil nitrification and acidification in stands invaded by black locust. Bacterial richness was the only component favoured by the invasion. On the contrary, abundance and richness of microarthropods, richness of nematodes, and richness and diversity of plant communities decreased significantly in invaded stands. The invasion process caused a compositional shift in all studied biotic communities and in relationships between the different ecosystem components. We obtained clear insights into the effects of invasion of managed native forests by black locust. Our data confirms that the alien species transforms several ecosystem components, modifying the plant-soil community and affecting biodiversity at different levels. Correct management of this aggressive invader in temperate forests is urgently required. [ABSTRACT FROM AUTHOR]