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The black weevil Aclees taiwanensis Kôno, 1933 (Coleoptera: Curculionidae) is a xylophagous insect native to Southeast Asia and introduced to Italy in 2005. Here, the species completes its entire life cycle on Ficus carica L., causing economic damage and leading to the plants' death. Nowadays, there are no insecticides registered for its control. In this study, a commercial product based on Beauveria bassiana, Naturalis®, was associated with Rincotrap® tissue. Semi-field trials were carried out on fig seedlings by comparing two different concentrations (3% and 10%) of this entomopathogenic fungus distributed in suspension on Rincotrap® bands. The results showed that the fungal product had a biocidal effect in both treatments. Afterward, trials were conducted in a fig orchard in order to verify the effectiveness of this association in the field. The addition of Naturalis® at a 3% concentration to Rincotrap® bands did not alter the number of adults captured. The total mortality was 43.7% and 23.8%, respectively, in the treated and control plots. Among the total number of dead adults, only the mortality rates of B. bassiana exceeded 70% in both plots. Further long-term studies in several environments are necessary to improve this technique and create an integrated control system for the black fig weevil. [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.

Xylosandrus compactus and Liparthrum colchicum are two Scolytinae recorded for the first time in Italy in 2011 and 2019, respectively. X. compactus is an "ambrosia beetle" causing damages to several plants typical of the Mediterranean maquis through its digging activity on twigs and branches of the host plants. L. colchicum is a "bark beetle", monophagous on laurel shrubs and trees. During a survey performed in summer of 2020, in "Tenuta Salviati" located in the Migliarino Natural Park (Pisa, Tuscany), adults of X. compactus and L. colchicum were collected from the same branches and apical twigs of Laurus nobilis hedges. The study aimed at characterizing fungi isolated from the external surface of the two scolytids bodies, to evaluate similarities and even their role in fungal spreading in the environment. [ABSTRACT FROM AUTHOR]

The vector-borne bacterium Xylella fastidiosa (Wells and Raju) causes several serious diseases to plants. Recently, different subspecies of X. fastidiosa were reported in some European countries. The risk of the bacterium's spread on the entire European territory is very high; therefore, it has been added into the priority pest list (2019/1702/EU Regulation). The main purposes of this work were to verify the presence of potential vectors in areas at a high risk of introduction in Tuscany and to ascertain the presence of X. fastidiosa in these insect vectors. Over 4,000 Auchenorrhyncha were collected and analysed from 2015 to 2019. Among the xylem sap-feeder putative vectors, most of the insects collected belonged to the family Aphrophoridae, but also many species of leafhopper were identified. Overall, in Tuscany four species were the most represented: Philaenus spumarius (L.), Cicadella viridis (L.), Synophropsis lauri (Horvath) and Neophilaenus campestris (Fallen). In 2018 an outbreak of X. fastidiosa subsp. multiplex was reported in Monte Argentario (Grosseto province, Tuscany). In 2019 X. fastidiosa subspecies multiplex ST 87 was detected in seven P. spumarius and three N. campestris collected from the infected area. [ABSTRACT FROM AUTHOR]

Liparthrum colchicum Semenov (Coleoptera Curculionidae Scolytinae) is a relatively unknown monophagous insect species primarily associated with thin dried twigs (about 0.5-1cm in diameter) of Laurel (Laurus nobilis). After being caught in traps located at Italian ports, it was initially considered an intercepted species alien to the country. However, recent findings, suggest that this beetle may have a different origin. Several records from different sites of Tuscany and Latium showed that it could be relatively widespread in Italy. These observations strengthened the hypothesis that this scolytid, harmless to L. nobilis, might be already established or even native to the country. Therefore, we argue that it could have been easily overlooked thus far, as it thrives only in twigs already wilted due to different environmental factors. Moreover, field observations, carried out in the two Italian Regions, evidenced high frequencies of its infestations in Laurel twigs previously colonized by Xylosandrus compactus. Notes on the taxonomy and biology of this species are also reported in the present work. [ABSTRACT FROM AUTHOR]

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]

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]

Halyomorpha halys is a severe invasive Asian pest worldwide and classical biological control is foreseen as the most promising control method. Egg parasitoids appear to be the most important natural enemies of this pest, especially the Asian hymenopteran Trissolcus japonicus. In the invaded areas, only a few egg parasitoid species have been able to adopt H. halys as a host. Anastatus bifasciatus is the most common native egg parasitoid of H. halys in Europe, but reaches only low levels of parasitization, while several other native species are only occasionally found. Recently, adventive populations have been found both in the USA and in Europe of T. japonicus, and in Italy of a second Asian species, Trissolcus mitsukurii. Species identification based on morphological traits by specialists or by molecular analysis is a crucial step in the management of biological control programs. The ability to identify the genus or species within a narrow guild of egg parasitoids based on adult emergence holes and meconium features can be a simple and useful method to support management efforts. We present here detailed descriptions of the meconium of the most frequent parasitoid species attacking H. halys in Europe and the characteristics of their emergence holes of the adult wasps. [ABSTRACT FROM AUTHOR]

The Italian distribution range between Piedmont and Lombardy interested by the outbreak of the exotic Japanese beetle (JB) Popillia japonica Newman (Coleoptera Scarabaeidae) is getting wider. In the past, in the USA, where P. japonica is an exotic pest too, entomopathogenic fungi have been extensively used against larvae and adults of the Japanese beetle. We tested under laboratory and field conditions the effectiveness of a home-made 'attract-infect-release' device against P. japonica adults. The device was activated alternatively with the two commercial products (GranMet® and Met52®), available in Italy, containing Metarhizium brunneum Petch. During a series of fifteen-minute observations we recorded a mean permanence time of adult beetles inside the device of about 3 minutes with no difference between treatments. The number of P. japonica adult-borne conidia was assessed in the laboratory with no significant differences between treatments. For what concerns GranMet®, experiments on horizontal transmission showed 100% mortality by 19 days after treatment, while mortality associated with Met52® was 30-65%. In conclusion, our research showed that a 3-minute contact between a P. japonica adult and GranMet® was enough to permit the transmission of the infection to other individuals and eventually kill the insect. This result appears to be promising and, if confirmed in large field experiments, could add a new device for the biological control strategies against the Japanese beetle. [ABSTRACT FROM AUTHOR]

The Japanese beetle Popillia japonica Newman is a US and EU quarantine insect pest that has recently invaded northern Italy. Its ability to rapidly spread in new areas makes this insect a threat to agriculture. In the last decades, several trials on biological control of the Japanese beetle by entomopathogenic nematodes and fungi have been carried out with variable efficacy. However, the necessity of an integrated pest management approach to improve control has arisen. Long‐lasting insecticide‐treated nets (LLINs) have been used to control other agricultural pests with an attract‐and‐kill strategy. Here, we present results from laboratory evaluation of 2 LLINs, Storanet® (BASF™) and ZeroFly® (Vestergaard™), against P. japonica adults. Both were effective in killing the beetles; however, some differences emerged if different exposure times were compared: ZeroFly® always gave 100% mortality in tests from 5‐s to 30‐min exposure; Storanet® showed 100% mortality only with 30‐min exposure and going down to 89%–99% mortality for 5‐s to 15‐min exposure. A description of the paralysis process occurring at 5‐s exposure is given. Possible field application of LLINs within programs of integrated pest management is discussed. Integr Environ Assess Manag 2019;15:259–265. © 2018 SETAC Key Points: The biological invasion of Popillia japonica in Italy needs to be limited.In recent years, entomopathogenic nematodes and double‐lure traps have been employed with variable efficacy and have also created management problems.Here, we tested for the first time in the laboratory the use of 2 long‐lasting insecticide‐treated nets against this pest; the resulting high mortality indicates an additional way to create an integrated pest management approach to the outbreak. [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]

The exceptionally frequent entries of alien pest are a major source of concern for the farmers who have to protect their crops from unknown insects, often without natural enemies in the new areas. A new pest belonging to the Molytinae family (Coleoptera: Curculionidae), tribe Hylobiini, reported as Aclees sp. cf. foveatus Voss, was recently introduced in Italy. The species is responsible for severe damages in many Italian fig nurseries and orchards, particularly in the Italian Central Northern regions, i.e. Tuscany, Ligury and Latium. Currently, no active ingredients are registered against this insect on fig crops. An innovative and ecofriendly approach for controlling this exotic weevil infestation was investigated, by using montmorillonitebased clays, either in their native state or containing copper(II) species, and clinoptilolite zeolites, in order to check the perception of the adults' weevil towards the different solid materials and, subsequently, to evaluate the capability of these innovative products to act as masking agent with respect to the host plant and/or as repellent upon contact. The formulations containing copper(II)-exchanged clay and clinoptilolite zeolite showed preliminary promising results in terms of efficacy and environmental sustainability. [ABSTRACT FROM AUTHOR]

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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]

The recent introduction into Italy of the Japanese beetle (Popillia japonica Newman) has triggered new research on biological control agents aimed at limiting the spread of this alien pest. From the scientific literature it is known that the entomopathogenic nematode Heterorhabditis bacteriophora Poinar is very effective against P. japonica. Here we present a laboratory test comparing the lethal activity at three different concentrations of the commercial product Nematop® (CBC, Europe), containing H. bacteriophora, against P. japonica 3rd instars. The results showed that the lower dose (25 IJs/cm2) maintained an effectiveness of about 90%, thus not differing on the whole from the values of the other concentrations. Afterwards, this dose was tested in the field both in the spring and summer with grub killing values of 25 and 45%, respectively. [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]

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]

Rhynchophorus ferrugineus is considered the worst pest of palm species, and few natural enemies are reported for this parasite in its area of origin. Here, we report the first recovery of the entomopathogenic fungus Metarhizium pingshaense associated with R. ferrugineus from Vietnam. The morphological, biochemical, and toxicological features of this strain were studied and compared with those of another Metarhizium strain associated with this weevil in Sicily (Italy), an area of recent introduction. The potential use of these fungi as biocontrol agents was tested against adult insects in laboratory trials and a similar mortality rate was found. Both strains were able to produce toxins and cuticle-degrading proteases, but they showed dissimilar enzymatic and toxicological profiles, suggesting a different virulence activity. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent years, a new pest, the black weevil Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae) native to Asia, has been recorded in France and Italy. Aclees taiwanensis larvae cause the rapid death of the fig tree (Ficus carica), digging alimentation galleries in the trunk and surface roots, compromising the phloem flux. To date, no specific EU regulation has been applied to prevent the A. taiwanensis spread, and we can reasonably expect a rapid diffusion of this pest all over the Mediterranean area where F. carica is widespread. This paper updates the known distribution of this species in Southern Europe, using a citizen science approach, and describes, under laboratory and field conditions, its main biological traits. Ficus carica L. is one of the earliest cultivated fruit trees, and figs are a typical fruit of the Mediterranean diet and traditional medicine as well. In recent years, a new pest, the black weevil Aclees taiwanensis Kȏno, 1933 (Coleoptera: Curculionidae) native to Asia, has been recorded in France and Italy. Aclees taiwanensis causes the rapid death of the fig tree by its larvae that dig alimentation galleries in the trunk and surface roots, compromising the phloem flux. In Italy, from 2005, the year of the first detection of A. taiwanensis, the fig production has nearly halved, decreasing from 20.09 t to 10.65 t. To date, no specific EU regulation has been applied to prevent the A. taiwanensis spread, and we can reasonably expect a rapid diffusion of this pest all over the Mediterranean area. To avoid the loss of the Mediterranean fig orchards, effective strategies to detect and control the black weevil are required. Such strategies need a detailed knowledge of A. taiwanensis distribution, biology, and physiology. This paper updates the known distribution of this species in Southern Europe, using a citizen science approach, and describes, under laboratory and field conditions, its main biological traits. [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]

[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]

• 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]

Rhynchophorus palm weevils are large insects belonging to the family Dryophthoridae. All Rhynchophorus species are polyphagous and have a similar life history but some are major pests because of the serious economic damage they cause, in particular to several species of the family Arecaceae. Here we review the natural enemies of Rhynchophorus species in both their native and introduced regions of the world, to assess the possibility of biological control of this taxon. Moreover, particular attention is paid to the well-studied and harmful species Rhynchophorusferrugineus, about which more information is available, and to its natural enemies in the Mediterranean region, because the impact of this pest in this recently colonized area is particularly remarkable and also the recent trend in species management is looking for indigenous natural enemies. More than 50 natural enemies have been reported to attack Rhynchophorus species, even if most of them are associated to R. ferrugineus (Olivier), highlighting the lack of information on the other species of the genus. Pros and cons of all the biological control agents are then discussed: among the considered organisms, fungi are noteworthy to be considered for inclusion in integrated pest management programs. Overall, our overview underlines the need to increase knowledge on natural enemies of all the species of the genus Rhynchophorus, to isolate more virulent strains and to determine the optimum conditions for the actions of the biocontrol agents. [ABSTRACT FROM AUTHOR]