Agostino Strangi

The global invasion of the brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is responsible for high economic losses to agriculture worldwide. As classical biological control is considered the most effective long-term management approach, an intensified research activity has been carried out worldwide aimed at discovering the most effective natural enemies of BMSB. In western Slovenia, monitoring for the presence of stink bug egg parasitoids has been ongoing since 2019. The results from a five-year survey (2021–2025) indicate overall egg parasitism rate ranging from 8.5% to 33.8% over the study period, with an average of 19.6%. The native Anastatus bifasciatus (Geofrey) (Hymenoptera: Eupelmidae) was the most abundant and widespread parasitoid of BMSB in the region. It accounted for 47% of all parasitoids in the complex and parasitized 9.2% of the host’s eggs. It was followed by non-native Trissolcus mitsukurii (Ashmead) (Hymenoptera: Scelionidae) which represented 31% of the parasitoid complex and contributed 6.1% to the overall egg parasitism rate. Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) ranked third (21%) despite being recorded only in the final two years of the study, with contribution 4% to total egg parasitism rate. BMSB eggs were also parasitized in low numbers by Trissolcus basalis (Wollaston) and Trissolcus cultratus (Mayr) (Hymenoptera: Scelionidae). The first detection of T. japonicus in Slovenia in 2024, and its subsequent records in 2025, confirm its establishment in the country and represent an important milestone that may facilitate the future implementation of classical biological control of BMSB.

Pantoea stewartii subsp. stewartii (Pss) is a Gram-negative bacterium first documented in North America, and is the causal agent of Stewart’s disease in maize (Zea mays), especially in sweet corn. First identified in North America, it is primarily spread by insect vectors like the corn flea beetle (Chaetocnema Pulicaria) in the United States. However, Pss has since spread globally—reaching parts of Africa, Asia, the Americas, and Europe—mainly through the international seed trade. Although this trade is limited, it has still facilitated the pathogen’s global movement, as evidenced by numerous phytosanitary interceptions. Recent studies in Italy, as indicated in the EFSA journal, reported that potential alternative vectors were identified, including Phyllotreta spp. and the invasive Asian brown marmorated stink bug (Halyomorpha halys); the latter tested positive in PCR screenings, raising concerns due to its broad host range and global distribution. This information has prompted studies to verify the ability of Halyomorpha halys to vector Pss to assess the risk and prevent the further spread of Pss in Europe. In this study, we explored the potential transmission of Pss by the brown marmorated stink bugs in maize plants, following its feeding on Pss-inoculated maize, as well as the presence of Pss within the insect’s body.

Pantoea stewartii subsp. stewartii (Pss) is a Gram-negative bacterium native to the Americas and the causal agent of Stewart's disease in maize (Zea mays), which partic-ularly affects sweet corn. Although spread primarily by insect vectors such as the common corn flea beetle (Chaetocnema Pulicaria) in the United States, Pss has now been introduced globally, including regions in Africa, Asia, the Americas and Europe via the seed trade. Within the EU, it is a regulated quarantine pest. Although there have been detections in Italy since 2025, it is now considered eradicated. Surveillance and diagnostic efforts, supported by European and national projects such as Valitest, EURL-BAC and PROTEGGO, have focused on early detection and understanding of potential insect vectors. Recent studies in Italy have identified potential alternative vectors, including Phyllotreta spp. and the invasive Asian brown marmorated stink bug (Halyomorpha halys), the latter tested positive for Pss in PCR screenings, raising concerns due to its broad host range and global distribution. This information has prompted studies to verify the ability of Halyomorpha halys to vector Pss in order to assess the risk and prevent further spread of Pss in Europe. Studies have shown that in some cases the insect was able to take up the pathogen but was not able to transfer it to maize plants. Further studies should be conducted to verify whether other insects exist as potential vectors of Pss in Europe.

Thalassa montezumae Mulsant is a coccinellid species recently discovered as predator of the pine tortoise scale Toumeyella parvicornis. In this study, the complete mitochondrial genome of T. montezumae collected in Turks and Caicos Islands in 2023 was sequenced using next-generation sequencing techniques. The circular mitochondrial genome is 16,981 bp long and contains 13 protein coding genes, 22 transfer RNA, and 2 rRNA genes. Gene order is identical to that of other Coccinellidae. Phylogenetic analysis confirms structure of Coccinellidae families and tribes.

In Europe, the recently reported plant pathogen Xylella fastidiosa subsp. multiplex affects several wild, ornamental, and cultivated trees causing scorch diseases. In 2018, the sequence type 87 was reported in Tuscany on Mediterranean shrubs and trees. Although spittlebugs (Hemiptera: Aphrophoridae) were already identified as main vectors of this bacterium in Europe, their role in the transmission of this subspecies has not been ascertained yet. In this study the ability of Philaenus spumarius and Neophilaenus campestris to acquire and transmit Xylella fastidiosa subsp. multiplex sequence type 87 from and to Rhamnus alaternus was evaluated in two-year semi-field experiments. To acquire the bacterium, insects were confined on wild, naturally infected R. alaternus shrubs for 120 h. Then, they were transferred to healthy plants and maintained in cages for 96 h. To follow the infection, plant samples were collected every two months for three times. Tested plants were destroyed at the end of experiments and roots, twigs and leaves were analysed. Philaenus spumarius showed a significantly higher survival rate than N. campestris. The infection status of both insects and plants was assessed through molecular analysis. P. spumarius and N. campestris were able to infect healthy plants although the acquisition rate and the estimated probability of transmission appeared to be low. These findings provide new accounts on the role of two polyphagous insect vectors in spreading a quarantine organism, which is lethal to a huge number of plant species. However, further studies are needed to disclose more specific interactions within this complex pathosystem.

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.

The Japanese beetle, Popillia japonica, is a highly polyphagous Scarabaeidae native to Japan that colonized North America and Azores in the last century and has recently invaded Italy and Switzerland. Considering its economic impact on the horticulture and turfgrass industries, this species was ranked within the EU priority pests list in 2019. According to the EU Convention on Biological Diversity, the identification of invasion routes is a pivotal aspect in an effective management program aimed at controlling invasive alien species. To reconstruct the source of introductions of this pest, we investigated the genetic variability of P. japonica in its native and invaded areas worldwide by analyzing 9 microsatellite loci and two mitochondrial genes, COX I and CytB. In its native area, P. japonica is structured into two populations: one in the southern and another in the northern-central region of Japan. A limited area within central Japan was identified as the putative source of the North American outbreak. Moreover, the ABC inference and phylogeographic reconstruction suggest that two European populations originated from two independent introductions. The Azores Islands outbreak occurred approximately 50 years ago and originated from the southeastern region of North America (For simplicity, in this paper North America refers to Canada and the USA), while the second introduction, more recently, occurred in Italy and Switzerland and originated from northeastern region of North America.

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.

The Japanese beetle, Popillia japonica, is a highly polyphagous Scarabeidae native to Japan that colonized North America and Azores in the last century and has recently invaded Italy and Switzerland. Considering its economic impact to the horticulture and turfgrass industries, this species was ranked within the EU priority pests list in 2019. In order to reconstruct the source of introductions of this pest, we investigated the genetic variability of P. japonica in its native and invaded areas worldwide by analyzing 9 microsatellite loci and two mitochondrial genes, COI and CytB. There are two populations of Japanese beetles, from a limited area within central Japan, that are likely the source of the North American population. Moreover, the microsatellite data and resulting phylogeographic reconstruction suggests that the two European populations originated from independent introductions from southeast (Azores) and northeastern (Italy and Switzerland) North America ₍₁₎. (1) For simplicity, in this paper North America refers to Canada and USA

Geothermal soils in Central Italy are characterized by high temperatures (up to 60°C), low pH values, and sparse vegetation. The biodiversity of entomopathogenic soil fungi and nematodes has never been assessed in these areas. Soil samples (N = 12) separated from each other by at least 100 meters were collected in the areas of Le Biancane Natural Park (Grosseto) and Sasso Pisano (Pisa). The Galleria bait method was used to assess the presence of entomopathogenic fungi and nematodes. A total of nine species of fungi and one nematode were isolated and molecularly identified. All these species came from samples collected in the immediate surroundings of geothermal spring, apart from one Beauveria pseudobassiana collected at about 16 meters from the nearest spring. Moreover, Pristionchus uniformis previously reported only from North America and few European countries is recorded for the first time in Italy.