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In its native range, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) is a main egg parasitoid of Halyomorpha halys (Stål) (Hemiptera; Pentatomidae). Adventive populations of this parasitoid have been spreading in Europe and North America, allowing active distribution efforts in these areas to utilize it against H. halys in agriculture. We tested exposure of adults and parasitized egg masses to residues of a range of insecticides an adjuvant that the wasp could encounter in perennial horticultural crops, and how exposure might affect key behaviors. The insecticides included Burkholderia rinojensis, Methoxyfenozide, Sulfoxaflor, and Spinosad, and the adjuvant NuFilm®P. The lethal effects were investigated after exposure for 1, 6, and 24 hours to residues applied to Munger cells using a Potter spray tower to determine mortality levels. Sulfoxaflor and Spinosad resulted in 73% and 100% mortality after 24 hours at field rates, while Methoxyfenozide caused 19% mortality at the same rate. Little mortality occurred with Burkholderia rinojensis and NuFilm®P at recommended rates after 24 hours. Regarding sublethal effects, Spinosad, Sulfoxaflor, and Burkholderia rinojensis negatively impacted reproduction. Sulfoxaflor caused a lower angular velocity in parasitoids exposed to H. halys traces. Spinosad, Methoxyfenozide, and NuFilm®P induced a significantly lower overall circadian activity. Our results showed that precision timing of insecticide sprays to pests is necessary, especially for biocontrol programs that involve the release of parasitoids such as T. japonicus. Our results also illustrate how sensor data acquisition and behavioral analysis software can be utilized to detect important sublethal effects such as circadian disruption in minute parasitoids. [ABSTRACT FROM AUTHOR]

Substrate-borne vibrational communication is common in pentatomids. Although several works exist on the vibrational communication of Halyomorpha halys, its vibrational behavior post diapause has not been investigated. In this study, we recorded H. halys overwintered adults using laser doppler vibrometers at three temperatures: 10 °C (inactivity), 18 °C (breaking of diapause), and 25 °C (peak of mating activity). The aim was to assess the effect of temperature on the signaling, motility, and survival of H. halys. The insects were sexed into different cages and recorded separately or joined with a cage of the opposite sex. We calculated the total time spent on signaling and walking per replica. The males predominantly emitted male signal 1 (MS1) throughout the four months of recordings. The females exclusively emitted female signal 2 (FS2) when joined with the opposite sex cage the first two months of recordings. Interestingly, they also started FS2 signaling when recorded separately, after two months. No signaling was recorded at 10 °C. At 25 °C, the signaling latency time before vibrational signaling was 24 h compared to 23 days at 18 °C. The short latency time at 25 °C correlated with a higher death rate in early stages of recording. Male walking activity was significantly higher in joined cages at 18 °C and 25 °C, suggesting the increased searching behavior near the opposite sex. Overwintered H. halys could adapt to different conditions whereas low temperatures maintain the diapause which is characterized by no signaling activity. Our results provide a foundation for bioclimatic modeling of climate change effects on H. halys and insights into the use of vibrational playbacks for mass trapping and monitoring as control techniques. [ABSTRACT FROM AUTHOR]

BACKGROUND: Classical biological control has been identified as the most promising approach to limit the impact of the invasive pest species Halyomorpha halys (Heteroptera: Pentatomidae). This study investigated the parasitism rate at sites where the biocontrol agent Trissolcus japonicus (Hymenoptera: Scelionidae) was released and where its unintentional introduction took place, in the Trentino–South Tyrol region. The effect of land‐use composition was studied to understand which factors favor the establishment of hosts and parasitoids, including native and exotic species. RESULTS: The released T. japonicus were detected a year after the start of the program, with a significant parasitoid impact and discovery, compared to control sites. Trissolcus japonicus was the most abundant H. halys parasitoid, and Trissolcus mitsukurii and Anastatus bifasciatus were recorded also. The efficacy of T. mitsukurii was lower in sites where T. japonicus was successfully established, suggesting a possible competitive interaction. Parasitism level by T. japonicus at the release sites was 12.5% in 2020 and 16.4% in 2021. The combined effect of predation and parasitization increased H. halys mortality up to 50% at the release sites. Landscape composition analysis showed that both H. halys and T. japonicus were more likely to be found at sites with lower altitude and with permanent crops, whereas other hosts and parasitoids preferred different conditions. CONCLUSION: Trissolcus japonicus showed a promising impact on H. halys, at release and adventive sites, with minor nontarget effects, mediated by landscape heterogeneity. The prevalence of T. japonicus in landscapes with permanent crops could support IPM in the future. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Controlling the brown marmorated stink bug without chemical insecticides is challenging. The sterile insect technique, based on use of irradiated sterile males to reduce fertility of wild females, is a valid method in area-wide pest management. This work complements previous investigations that were carried out by treating newly emerged males at lower irradiation doses. In this study, high irradiation doses (32 and 40 Gy) were applied, using a linear accelerator, to a colony of wild overwintering adults collected in large numbers in the field during the aggregation phase before the winter diapause. A sterility level of 95% was reached with a minimum 32 Gy X-ray irradiation dose and without significant impacts on other physiological parameters, such as fecundity and longevity. The brown marmorated stink bug, Halyomorpha halys, is a pentatomid bug of Eastern Asian origin that became an economically relevant pest in the Eurasian and American continents. Management of this species is limited to use of chemical insecticides: an inefficient method due to the strong adaptability of the target pest. The sterile insect technique (SIT) is potentially a valid tactic in the search for nontoxic alternatives. In this work, we investigated the suitability of mass-trapped overwintering males, collected during the aggregation phase before the winter diapause, for their release as competitive sterile males in an SIT programme. Differently from previous studies, irradiation was applied with a linear accelerator device that produced high-energy photons. Following a similar scientific protocol with newly emerged irradiated males, the effects of X-ray irradiation on physiological parameters (longevity, fecundity and fertility) were assessed. In addition, behavioural bioassays were carried out in no-choice conditions to evaluate if irradiation interferes with mating processes. The results are very encouraging; the effects of the irradiation at 32 Gy did not differ from the controls in the longevity or fecundity of the exposed overwintering adults. The hatching rate of the eggs laid by the fertile females that had mated with the irradiated males was less than 5%. The results of behavioural bioassays showed that the irradiation did not cause a significant impact on the quality of the sterile males. More research is warranted to evaluate the mating competitiveness of sterile males in semi-field and field conditions. [ABSTRACT FROM AUTHOR]

Halyomorpha halys (Stål, 1855), the brown marmorated stink bug (BMSB), is an invasive species that has become a key agricultural pest in its invaded range. Commercial traps available for BMSB monitoring rely on male produced aggregation pheromones as lure, with two possible shortcomings: trap spillover and low detection precision. In this study, we assessed if vibrational signals can increase the attractiveness of pheromone traps by testing the optimized vibration-based lure (Female Song 2, FS2) associated with a specifically designed trap (i.e., the vibrotrap). We evaluated the efficacy of this bimodal trap (i.e., pheromones + vibrations) on females, males and nymphs in controlled conditions (greenhouse) and in the field, in two sites at the margin of two commercial vineyards. In the field, bimodal vibrotraps were compared to three unimodal (i.e., only pheromone) trap types. Both experiments showed that the vibrotrap is highly attractive for BMSB, and the optimized FS2 signal significantly improved its effectiveness. Even though FS2 was selected to target males, the number of trapped females increased as well. Overall, the presented findings show a feasible improvement to future commercial BMSB traps through the synergic use of semiophysicals and semiochemicals. Further research is needed to evaluate the effectiveness of vibrotraps for both early detection and mass trapping. [ABSTRACT FROM AUTHOR]

Environmental conditions are crucial factors that influence communication systems and affect animal behavior. Research in the field of biotremology has improved our understanding of insect behavior, ecology, and evolution. However, the interactions between vibrational signaling and environmental factors are less studied, mainly because of technical issues faced in field trials. We therefore developed and tested an approach to investigate the effect of abiotic factors on insect vibrational signaling and explored its implementation as a monitoring tool for insect vibrational signals, using a vineyard as an agroecosystem model. Our results showed a significant decrease in insect signaling activity during unsuitable conditions of high temperature and wind velocity. We determined for the first time, the daily signaling pattern of the two insect pests, Scaphoideus titanus and Halyomorpha halys, in natural conditions. Biotremology techniques could be profitably used to monitor not only the presence of target pest species but also the biodiversity associated with vibrational signaling insects. In particular, the method implemented in this study could be used as a tool to compare the quality of cultivated areas under different management systems. [ABSTRACT FROM AUTHOR]

These parasitoid species have been detected in Pakistan using sentinel eggs, an extremely valid biocontrol tactic based on exposing a consistent number of eggs of the target pest species for an amount of time suitable to obtain the egg parasitoid oviposition [[17]]. The overall effect of dose and cross types on the number of eclosed eggs, the number of oviposited eggs, and the proportion of eggs hatched per female are reported. [Extracted from the article]

The brown marmorated stink bug (BMSB), Halyomorpha halys Stål, is an invasive species and a polyphagous pest. BMSB feeding activity was suspected to be responsible for olive damage. To evaluate the effect of feeding damage from adults and nymphs of BMSB, 30 rearing sleeves were positioned in an olive grove, at an early stage of drupe development. The individuals were kept in the rearing sleeves for 48 h, and the number of olives in each sleeve was checked weekly, visually assessing signs of damage and measuring their volume. After the 48‐hr exposure, the number of early dropped olives was significantly higher for rearing sleeves containing BMSB adults and nymphs compared with control, with visible signs of damage. The volume of olives still attached was significantly lower for rearing sleeves with adults. These results provide key evidence on BMSB damage in developing olives. If the numbers of BMSB keep increasing in Mediterranean regions (where most of the olive production occurs), actions should be taken to prevent economic losses. [ABSTRACT FROM AUTHOR]

Simple Summary: When an alien species reaches a new environment, the natural enemies present in that habitat might fail to regulate its population as they might not be host-adapted. Hence, the best solution might be the use of alien biological control agents that are co-evolved with the exotic pest in question. This is the case of Halyomorpha halys, which is native to Asia and has recently invaded Europe and the Americas. Trissolcus japonicus and Trissolcus mitsukurii are among its main parasitoids. Adventive populations of the latter were found in Northern Italy, suggesting its employment within augmentative biological control. Homologous programs with T. japonicus are already ongoing in Italy. This procedure implies releasing the parasitoid to increase its population and spread to new areas invaded by H. halys. However, a fundamental aspect that must be investigated is the risk-assessment beforehand, i.e., the systematic process of identifying the hazard associated with such a procedure. In this context, the preference of T. japonicus and T. mitsukurii between two stinkbugs was evaluated in this study. We found that T. japonicus preferred the naturally released traces of H. halys while T. mitsukurii exhibited a higher preference for the natural and synthetic chemical cues of N. viridula. Trissolcus mitsukurii and Trissolcus japonicus are two Asian egg parasitoids associated with different pentatomids such as Halyomorpha halys. Adventive populations of T. mitsukurii were found in Northern Italy, suggesting its employment as a biological control agent (BCA) against H. halys. Nevertheless, to reduce the latter's population, T. japonicus was released in Italy. Releasing an exotic parasitoid requires investigating the interaction between the BCA and the environment to avoid negative impacts on the entomofauna of the new habitat. Trissolcus mitsukurii is mainly associated with Nezara viridula in its native area. Therefore, we investigated and compared the ability of female T. mitsukurii and T. japonicus to distinguish between naturally released cues of H. halys and N. viridula. A single parasitoid was exposed to contact kairomones of both pests to evaluate its modifications in orthokinetic and locomotory behaviour. The behaviour of female T. mitsukurii was also tested on synthetic compounds simulating the cues of the two pentatomids. When naturally released cues were used, T. japonicus preferred the traces of H. halys, while T. mitsukurii preferred N. viridula's cues. Moreover, the attraction of T. mitsukurii to N. viridula's cues was confirmed with synthetic cues. Additional studies are needed to judge if this parasitoid can be used as a BCA. [ABSTRACT FROM AUTHOR]

BACKGROUND: Many groups of insects utilize substrate‐borne vibrations for intraspecific communication. This characteristic makes them a suitable model for exploring the use of vibrations as a tool for pest control as an alternative to the use of chemicals. Detailed knowledge of species communication is a prerequisite to select the best signals to use. This study explored the use of substrate‐borne vibrations for pest control of the brown marmorated stink bug (BMSB), Halyomorpha halys Stål (Heteroptera: Pentatomidae). For this purpose, we first identified the spectral and temporal characteristics that best elicit male responsiveness. Bioassays were conducted with artificial signals that mimicked the natural female calling signal. Second, we used the acquired knowledge to synthesize new signals endowed with different degrees of attractiveness in single‐ and two‐choice bioassays using a wooden custom‐made T stand. RESULTS: The results from this study showed that males were attracted to female signals along a high range of amplitudes, especially starting from a threshold of 100 μm s−1, a high pulse repetition time (1 s) and frequency peak corresponding to the first harmonic (76 Hz). This resulted in an "optimal" signal for use to attract males, while the choice test in the T arena showed that this signal elicits searching behavior and attracts BMSB males towards a stimulation point. CONCLUSION: We confirm the use of vibrational signals as a strong tool for behavioral manipulation of male BMSB and suggest its possible use in the development of field traps and further management of this pest. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The green leafhopper, Empoasca vitis, is a polyphagous pest of grapevine and tea plants. To date population density is controlled primarily by insecticides and there is a demand for more sustainable controls. To develop a vibrational mating disruption method, the natural occurrence of a 'disruptive signal' was investigated. Further, the efficacy of natural and artificial 'disruptive signals' was determined. Results: With behavioral trials we described male rivalry and recorded a species‐specific disruptive signal (DP). The DP, a single pulse overlapping the competitor male call, interfered with the rival's ability to locate the female. Laboratory playback disruption trials revealed that the pair formation process was prevented by artificial disturbance noises that included the following features: E. vitis DP, Scaphoideus titanus disturbance noise, and a pure tone (250 Hz). Among these, the pure tone was most efficient at preventing mating. Conclusion: Results support development of a vibrational mating disruption method as a control strategy for E. vitis. To simultaneously disrupt the mating of E. vitis and S. titanus, the possibility of applying the S. titanus disturbance noise combined with the pure tone is discussed. © 2018 Society of Chemical Industry Natural (i.e. intra and interspecific) and synthetic masking signals successfully interrupted the mating behavior of the leafhopper Empoasca vitis. The synthetic pure tone was the most effective mating disruptor. [ABSTRACT FROM AUTHOR]

Despite the increasing number of studies on the use of acoustic stimuli to control agricultural pests, this approach is still theoretical. Many insect pests, in particular hemipterans, use vibrational signals for mating communication, and therefore the application of a control strategy based on acoustic interference is a promising option. The Brown Marmorated Stink Bug, Halyomorpha halys, is causing severe economic damage to many crops in the USA and Italy. We tested a female vibrational signal, female signal 2 (FS2), to attract males in different settings, such as natural substrates, arenas and a cage representing an acoustic trap. We used video-tracking analysis and described the vibrational amplitude field around the individuals to study the male behavior. We found that FS2 can attract more than 50% of males to the source point and has a strong 'loitering' effect on searching males that tend to remain in the stimulated area. We concluded that FS2 exhibits good attractiveness to H. halys males and that its potential use as a tool integrated into the currently existing pheromone traps should be tested in the field. [ABSTRACT FROM AUTHOR]

Improvements to current brown marmorated stink bug (BMSB), Halyomorpha halys, surveillance and killing systems are needed to improve detection sensitivity and to reduce pesticide use. Detection of BMSB in New Zealand with traps is reliant on sticky panels with aggregation pheromone, which are low cost but inefficient compared with beating foliage. Trapping for BMSB adults and nymphs was conducted daily with lethal traps consisting of an aggregation pheromone-baited-coat hanger covered with dark-colored long-lasting insecticide-treated mesh, we termed "The Nazgȗl", based on its sinister appearance. A deep tray lined with white plastic was attached centrally at the base for collecting the dead BMSB. The lethal traps killed and caught up to 3.5-fold more nymphs and adult BMSB than identically-baited sticky panels in the 3 weeks of deployment, and provided a snapshot of phenology by instar. We expect that lure-and-kill stations could contribute to the suppression of a delimited population and could be included as part of a semiochemical-based eradication program. Attracting and killing females and nymphs, thus removing future offspring, could contribute to population suppression during an eradication. [ABSTRACT FROM AUTHOR]

"BugMap" is a citizen science mobile application that provides a platform for amateur and expert scientists to report sightings of two invasive insect pests, the tiger mosquito Aedes albopictus Skuse (Diptera: Culicidae) and the brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae). The latter is a notorious pest of fruit trees, vegetables, ornamentals, and row crops, inflicting severe agricultural and ecological disturbances in invaded areas. Our approach consists of coupling traditional monitoring with citizen science to uncover H. halys invasion in Trentino. The project was initiated in 2016 and the first results were reported in 2018. Here, we revisit our initiative four years after its adoption and unravel new information related to the invader dispersal and overwintering capacity. We found that our previous model predicted the current distribution of H. halys in Trentino with an accuracy of 72.5%. A new MaxEnt model was generated by pooling all reports received so far, providing a clearer perspective on areas at risk of stink bug establishment in this north Italian region. The information herein presented is of immediate importance for enhancing monitoring strategies of this pest and for refining its integrated management tactics. [ABSTRACT FROM AUTHOR]

The sterility of eggs and nymphs from gamma-irradiated male Halyomorpha halys was investigated to determine the potential for the sterile insect technique (SIT). Males irradiated at 0, 16, 24 and 32 Gy were placed with untreated virgin females, and egg sterility was determined, showing 54.3% at 16 Gy. The percentage of sterility from irradiation was 26 percent lower than previous results from the USA and the variance was very high. Competitive overflooding ratio trials between irradiated virgin males and fertile virgin males at a 5:1 ratio resulted in the expected egg sterility, indicating competitive performance by irradiated males. By July and August, older, irradiated overwintered males were significantly less competitive than similar, non-irradiated males. There is a need to revisit the irradiation delivery method to achieve proper precision around the paternal dose required for an expected >80% egg sterility and subsequent ~99% endpoint sterility estimated at adult emergence in the F1 phase. These results suggest that the mating competitiveness and competency of males after irradiation at 16 Gy is not limiting to the sterile insect technique for suppression. A wild harvest of overwintering males using the aggregation pheromone, followed by irradiation and male release, might replace rearing. Mass-collected, sterilized bugs could be transported from an area of high H. halys density and shipped for release to enable suppression or eradication elsewhere. This concept is under development but further work is needed now to understand the difference in results between the US and Italian irradiators and increase the reliability of dosimetry. [ABSTRACT FROM AUTHOR]

Surveillance for detection of the brown marmorated stink bug, Halyomorpha halys, is reliant on sticky panels with aggregation pheromone, which are low cost, but very inefficient (est. 3%). Trapping for adults was conducted in Italy with novel live (or lethal) traps consisting of aggregation pheromone-baited cylinders with a wind vane, with the upwind end covered by mesh and the downwind end sealed by a removable entry-only mesh cone, admitting the attracted bugs. The novel traps caught up to 15-times more adult H. halys than identically-baited sticky panels in two weeks of daily checking (n = 6 replicates) (the new live traps were, in Run 1, 5-, 9-, 15-, 13-, 4-, 12-, 2-fold; and in Run 2, 7-, 1-, 3-, 7-, 6-, 6-, and 5-fold better than sticky traps, daily). The maximum catch of the new traps was 96 live adults in one trap in 24 h and the average improvement was ~7-fold compared with sticky panels. The rotating live traps, which exploit a mesh funnel facing the plume downwind that proved useful for collecting adults, could also be used to kill bugs. We expect that commercially-available traps could replace the crude prototypes we constructed quickly from local materials, at low cost, as long as the principles of a suitable plume structure were observed, as we discuss. The traps could be useful for the sterile insect technique, supporting rearing colonies, or to kill bugs. [ABSTRACT FROM AUTHOR]

Halyomorpha halys is an invasive stink bug, native to east Asia, responsible for extensive economic loss in numerous crops. Since several factors can influence the severity of the recorded injury level, we performed field and semi‐field experiments in commercial apple orchards to monitor their interaction. To establish how position (both in the orchard and on the canopy), management and cultivar interact in determining pre‐harvest injury levels, more than 100,000 apples, distributed over 106 orchard blocks, were examined in the field. Apples located higher in the canopy, on edge rows and in orchards with organic management had a higher number of external injuries and such factors were more relevant when occurring in combination, and on mid and late‐season cultivars. Exclusion cages were used to assess if the injury severity changed with the apple growth stage and with the life stage of H. halys, exposing Red delicious apples to adults and nymphs for 48 hours, from May to July. Early‐season injuries did not evolve in distinct depressions nor in wide areas with necrotic tissue. Later in season, the injury severity was higher and similar for adults and older nymphs (fourth and fifth instars), with the development of depressions externally and necrotic tissue internally. Thus, even a low number of individuals could cause severe damage, over a short exposure period, when it happened near full maturation. The combined results offer new insights to support the development of informed and sustainable control strategies. [ABSTRACT FROM AUTHOR]

The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an invasive insect pest that has caused significant economic losses in a myriad of agricultural crops in Europe and the USA. The communication as well as the control of this pest largely rely on semiochemicals (e.g., pheromones) and semiophysicals (e.g., substrate‐borne vibrations). Nevertheless, the nocturnal activity of H. halys is still largely unknown. In the present study, the diel vibrational communication of H. halys was investigated in controlled laboratory and semi‐field conditions. Moreover, the relevance of this ecological trait for integrated pest management (IPM) strategies was assessed by extending playback periods of bimodal (i.e., pheromones + vibrational playbacks) traps to 24 h, and comparing it to the current trap model (solar panel, about 12 h of playback) and a control (no playback, only pheromone). We found that H. halys did not exhibit discernible differences of vibrational activity between photophase and scotophase, with the exception of signal type 2 that in laboratory conditions was predominately emitted within nocturnal and morning hours (i.e., 20:00–12:00). Additionally, the calling activity was negatively affected by warmer (>32 °C) and windier (>7 m s−1) conditions in semi‐field settings. Bimodal traps that were power‐supplied for 24 h captured significantly more males than the other groups, and more females than the control group. Results suggest that the nocturnal vibrational activity of H. halys should be accounted for within IPM strategies by activating the bimodal traps also during the scotophase. [ABSTRACT FROM AUTHOR]