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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.

Popillia japonica is a quarantine pest of priority interest for the EU, given its potentially important economic, social and environmental impacts. Alternative strategies to chemical methods are essential to limit its spread in newly infested areas with favourable climatic and environmental conditions. Saponins are biologically active molecules widely distributed in plants, displaying a well‐known repellent activity combined with a mortality effect against insects. In this context, saponins were extracted from alfalfa Medicago sativa, where medicagenic and zanhic acid glycosides and Soyasaponin I were the most abundant compounds and used in the laboratory and semi‐field experiments for treating leaves of susceptible host plants for P. japonica. Under laboratory conditions, a food deterrence effect and a significant mortality rate were observed using Corylus avellana leaves treated at increasing saponin concentrations, ranging from 1% to 5% w/v. Semi‐field condition experiment supported the food deterrence effect, as a significant food preference was observed for untreated plants of Vitis vinifera compared to treated plants. The promising results obtained suggest that alfalfa saponins could represent a potential eco‐friendly approach for Japanese beetle control. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Japanese beetle Popillia japonica Newman is an insect pest native to Japan that has spread into North America, the Azores and, recently, into continental Europe. Here, we present a study assessing the effectiveness of a long‐lasting insecticide‐treated net (LLIN), assembled in semiochemical‐baited attract‐and‐kill devices (A&Ks) as a low environmental impact means to control P. japonica in the field. We compared the attractiveness of three different forms of A&Ks that were left outdoors throughout the summer, and the residence time of P. japonica landing on them. Moreover, we performed a preliminary study testing the effectiveness of new LLINs after storage. Collected data also allowed us to investigate the beetles' diel flight patterns in relation to meteorological conditions. RESULTS: Killing effectiveness of the field‐exposed A&Ks declined steadily over the flight season (from 100% to 37.5%) associated with a decrease in residues of α‐cypermethrin, the active ingredient in the LLINs. The different A&K forms (pyramidal, octahedral and ellipsoidal) attracted similar numbers of beetles. Individual beetles' residence time ranged from 75 to 95 s and differed slightly between A&K forms. Effectiveness of LLINs decreased by ≈30% after 1 year storage. Based on numbers landing on A&Ks, the beetles' flight activity peaked about 14:30 h and was inversely correlated with relative humidity. CONCLUSION: This study indicates that semiochemical‐baited A&Ks are effective for controlling P. japonica in the field. Because of active ingredient decay, the LLINs should be replaced after 30–40 days of field exposure to ensure that the A&Ks remain fully functional. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The olive fruit fly Bactrocera oleae is one of the most serious and economically damaging insects worldwide, affecting the quality and quantity of both olive oil and table olives. Laboratory bioassays were conducted for the first time to evaluate the susceptibility of B. oleae pupae to two entomopathogenic nematodes (EPN) species, Steinernema carpocapsae and Heterorhabditis bacteriophora. The nematodes tested caused pupal mortality of 62.5% and 40.6%, respectively. The most noteworthy result was obtained with S. carpocapsae which was able to infect 21.9% of the emerged adults. Since this tephritid fly spent several months in the soil as pupa, the use of EPNs could be a promising method to control this pest.

Parasites and pathogens can follow different patterns of infection depending on the host developmental stage or sex. In fact, immune function is energetically costly for hosts and trade‐offs exist between immune defenses and life history traits as growth, development and reproduction and organisms should thus optimize immune defense through their life cycle according to their developmental stage. Identifying the most susceptible target and the most virulent pathogen is particularly important in the case of insect pests, in order to develop effective control strategies targeting the most vulnerable individuals with the most effective control agent. Here, we carried out laboratory tests to identify the most susceptible target of infection by infecting different stages of the red palm weevil Rhynchophorus ferrugineus (larvae, pupae, male, and female adults) with both a generic pathogen, antibiotic‐resistant Gram‐negative bacteria Escherichia coli XL1‐Blue, and two specific strains of entomopathogenic nematodes (EPNs), Steinernema carpocapsae ItS‐CAO1 and Heterorhabditis bacteriophora ItH‐LU1. By evaluating bacterial clearance, host mortality and parasite progeny release, we demonstrate that larvae are more resistant than adults to bacterial challenge and they release less EPNs progeny after infection despite a higher mortality compared to adults. Considering the two EPN strains, S. carpocapsae was more virulent than H. bacteriophora both in terms of host mortality and more abundant progeny released by hosts after death. The outcomes attained with unspecific and specific pathogens provide useful information for a more efficient and sustainable management of this invasive pest. [ABSTRACT FROM AUTHOR]

During the annual monitoring surveys for the pinewood nematodes, Bursaphelenchus xylophilus, conducted in the Tuscany region (Central Italy) from the year 2015 to 2019, a total of 1,025 wood samples were collected from symptomatic plants in coniferous forests. Among the eight Bursaphelenchus species found, Bursaphelenchus abietinus and B. andrassyi were identified through morphological and molecular analysis and recorded for the first time in Italy. Additionally, new associations between Bursaphelenchus species and the host plants or insect vectors have been reported. The generalized linear models performed to investigate the possible relation between the level of coniferous plant decay and the occurrence of Bursaphelenchus nematodes highlighted that the probability of the Bursaphelenchus presence in the samples increased with the degeneration of the phytosanitary state of the tree, the presence of blue stain fungi and different types of insects. [ABSTRACT FROM AUTHOR]

The olive fruit fly Bactrocera oleae is one of the most serious and economically damaging insects worldwide, affecting the quality and quantity of both olive oil and table olives. Third instar larvae and pupae of several Tephritidae flies were reported to be susceptible to entomopathogenic nematodes (EPNs), but few studies have been carried out on the olive fruit fly. Laboratory assays were conducted to evaluate the susceptibility of B. oleae larvae and pupae to two commercial EPN species, Steinernema feltiae and Heterorhabditis bacteriophora and two indigenous Italian strains of H. bacteriophora and Steinernema carpocapsae. Moreover, an olive assay in the soil was performed to evaluate the capability of EPN strains to enter inside the olive fruits and interact with B. oleae during the pupal stage or the emergence of adults in the winter diapause. The susceptibility assays with B. oleae were performed in well plates, filled with sterile soil (n = 30 for each EPN strain and insect stage). Adult emergence and mortality were recorded daily for 15 days. Dead pupae and adults were dissected to assess nematode infection. The most noteworthy result was obtained with S. feltiae which was able to infect more than 80% of larvae and it killed the pupae inside olive fruits and the adults during their emergence with the same efficacy. Since this Tephritidae fly spends several months in the soil, the use of EPNs, in particular, S. feltiae may represent a promising method to control this pest. [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]

The scarab beetlePopillia japonica, a pest native to northern Japan, has been recently found in Italy. Entomopathogenic nematodes are useful for biological control of this invasive insect. Previous work showed that 1st and 2nd larval stages are more susceptible to nematodes than 3rd instars. We tested the effectiveness ofHeterorhabditis bacteriophorain the laboratory againstP. japonica3rd instars. Experiments were conducted in Italy with larvae field collected in the fall, winter and spring, showing a significant decrease in effectiveness from the fall to spring. [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]

Meloidogyne graminicola is one of the most harmful organisms in rice cultivation throughout the world. This pest was detected for the first time in mainland Europe (Northern Italy) in 2016 and was subsequently added to the EPPO Alert List. To date, few methods are available for the control of M. graminicola and new solutions are required. In 2019, field trials using rice plants as trap crops were performed in a Lombardy region rice field where five plots for three different management approaches were staked out: (i) Uncultivated; (ii) Treated: three separate cycles of rice production where plants were sown and destroyed each time at the second leaf stage; (iii) Control: rice was sown and left to grow until the end of the three cycles in treated plots. The results showed that in the treated plots, the nematode density and the root gall index were lower than for the other two management approaches. Moreover, the plant population density and rice plant growth were higher than the uncultivated and control plots. In conclusion, the use of the trap crop technique for the control of M. graminicola gave good results and thus it could be a new phytosanitary measure to control this pest in rice crop areas. [ABSTRACT FROM AUTHOR]

Simple Summary: The Japanese beetle Popillia japonica is considered one of the most harmful organisms in the world for crops and the urban landscape. Popillia japonica spends most of its life cycle in the soil as a larva. At this stage, this beetle is more susceptible to biological control agents like entomopathogenic nematodes, which are obligate parasites of main soil-inhabiting insects, killing their host in just a few days. In 2014, P. japonica was detected in Northern Italy between the Piedmont and Lombardy regions. This research aims to investigate the natural occurrence of indigenous and locally adapted entomopathogenic nematodes along the Piedmont part of the Ticino river and test the most performing of them via bioassays. Natural isolates were recovered from 39 out of the 155 soil samples collected. The virulence of all entomopathogenic nematodes assessed by laboratory and semi-field assays highlighted that two isolates resulted in more efficiency in controlling P. japonica grubs. This result is very encouraging, and the use of these natural biocontrol agents against this pest is a fundamental component of eco-friendly management. The natural presence of entomopathogenic nematodes (EPNs) has been investigated in the Piedmont region (Northern Italy) in areas infested by the Japanese beetle Popillia japonica. Thirty-nine out of 155 soil samples (25.2%) were positive for EPNs. Most of the samples contained only steinermatids (92.3%), 5.1% contained heterorhabditids, and one sample (2.6%) contained both genera. All the recovered isolates were identified at species level both morphologically and molecularly. Steinernema carpocapsae was the most abundant and it was mainly distributed in open habitats, such as perennial meadows, uncultivated soils, and cropland, characterized by sandy loam soil texture and acidic pH. Steinernema feltiae has been found associated mainly with closed habitats such as coniferous and deciduous woodland, characterized by sandy loam-texture and extremely acidic soil. The three isolates of Heterorhabditis bacteriophora were collected only in open habitats (perennial meadows and uncultivated fields) characterized by strongly acidic soils with sandy loam texture. The virulence of all EPN natural strains was evaluated by laboratory assays against P. japonica third-instar larvae collected during two different periods of the year (spring, autumn). The results showed that larval mortality was higher for pre-wintering larvae than post-wintering ones. The five more promising EPN isolates were tested in the semi-field assay in which H. bacteriophora natural strains have been shown to be more efficient in controlling P. japonica grubs. All of these results are finally discussed considering the use of these natural EPNs as biological control agents against P. japonica, within an eco-friendly perspective of management. [ABSTRACT FROM AUTHOR]

Soil invertebrates represent almost a quarter of the total diversity of living organisms and their activity affects the entire soil ecological process. The choice of adequate thinning systems may differently affect soil nematode and microarthropod biodiversity in artificial black pinewoods. In this work, the results of the impact of different thinnings on the structure of nematode and microarthropod communities was reported. In a short-term experiment, thinning from below and selective thinning were compared to unmanaged stands to provide indications at the regional scale in central Italy. Soil nematode and microarthropod biodiversity was explored by examining community structure, assessing biodiversity. The interaction between environmental variables (crown volume, Photosynthetically Active Radiation, soil texture, soil temperature, and moisture) with taxa abundance of nematodes and microarthropods were also reported. The results indicated that the effects of thinning practices were temporary and varied between years. Soil nematode community shifted during the first and third years of thinning managements only in the Pratomagno site, while soil microarthropod community shifted in both sites only in the second year. The total nematode abundance was minimally affected by thinning practices, while the nematode community composition showed a decrease of omnivores and predators in the first years. Soil indicators showed inconsistent results. In microarthropods, mites and collembola were the least affected by thinning in terms of abundance and species biodiversity, while eu-edaphic taxa of Chilopoda, Diplopoda, and Pauropoda were not influenced by thinning, hemi-edaphic and epi-edaphic taxa of Coleoptera, Diptera, Hymenoptera, Tysanoptera, and Hemiptera were negatively affected. Soil indicators such as Shannon-Weiner and Simpson indices and soil biological quality (QBS-ar) improved in thinning from below in both sites. Soil temperature and moisture were the main driving factors in affecting soil nematode and microarthropods communities. Thinning from below probably allowed a more rapid recovery than selective thinning. [ABSTRACT FROM AUTHOR]

• The non-target effects of biological control agents are currently poorly known. • Entomopathogenic fungi and nematodes were tested against Popillia japonica. • A Before-After Control-Impact experiment was conducted to evaluate soil biota. • An indigenous nematode showed the strongest effect in decreasing P. japonica larvae. • No negative effect on non-target soil biota was found. Biological and integrated pest control are key assets to environmentally friendly management of cropland. Use of entomopathogens against target pests is common, yet the effects of such released organisms on native, non-target invertebrates are currently poorly known. This is particularly true for relatively inconspicuous components of agroecosystems such as soil biological biota. Popillia japonica , a polyphagous alien invasive scarab beetle native to Japan, is now present in Europe where huge efforts are being conducted to control the pest and slow its spread. In particular, entomopathogenic nematodes and fungi have been used for larval control. Here we test the effects of those agents on both P. japonica larvae and non-target soil biota by comparing soil arthropod assemblages before and after treatment of field plots in an irrigated perennial meadow. Application of an indigenous strain of the nematode Heterorhabditis bacteriophora resulted in significant reduction in numbers of P. japonica larvae. In contrast, an indigenous strain of the entomopathogenic fungus Metarhizium robertsii failed to provide significant control. We found no evident effect on non-target edaphic arthropods under either treatment in comparison to untreated control plots. Some taxa, namely Collembola and Acarina, showed a disproportionate increase in treated plots, suggesting that some changes may occur in the long term, at least in particular arthropod groups. Our results suggest the selected strain of H. bacteriophora is an excellent candidate for managing P. japonica larvae with minimal adverse impact on non-target species and ecosystem functioning. [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]

[Display omitted] • The natural occurrence of entomopathogenic fungi (EPF) was investigated in Piedmont. • Eighty-three out of 155 soil samples were positive for EPF presence. • Most of the isolates (94%) belonged to the genus Metarhizium. • M. robertsii 17/T02 showed high efficacy against P. japonica larvae in the lab tests. The natural occurrence of entomopathogenic fungi (EPF) was investigated along the Ticino River (Ticino River Natural Park, Novara Province, Piedmont, Italy), at the center of the area of the first settlement of the invasive alien pest Popillia japonica. Using Zimmermann's " Galleria bait method", EPF were successfully isolated from 83 out of 155 soil samples from different habitats (perennial, cultivated, or uncultivated meadows, woodlands, and riverbanks). Sequencing of the 5' end of the Translation Elongation Factor 1 alfa (5'-TEF) region allowed the assignment of 94% of the isolates to Metarhizium spp., while 8% and 7% were assigned to Beauveria spp. and Paecilomyces spp., respectively. Four Metarhizium species were identified: Metarhizium robertsii was the most common one (61.5% of the isolates), followed by M. brunneum (24.4%), M. lepidiotae (9%), and M. guizhouense (5.1%). Microsatellite marker analysis of the Metarhizium isolates revealed the presence of 27 different genotypes, i.e., 10 genotypes among M. robertsii , 8 among M. brunneum , 5 among M. lepidiotae, and 4 among M. guizhouense. Metarhizium brunneum appeared to be associated with woodlands and more acid soils, while the other species showed no clear association with a particular habitat. Laboratory virulence tests against P. japonica 3rd instar larvae allowed the identification of one M. robertsii isolate that showed efficacy as high as 80.3%. The importance of this kind of study in the frame of eco-friendly microbiological control is discussed. [ABSTRACT FROM AUTHOR]