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Simple Summary: The brown marmorated stink bug, Halyomorpha halys, native to Asia, is now an insect pest in several countries. The sterile insect technique (SIT), involving the sterilization of insects by ionizing radiation and field release, is one method to control insect pest. This study examines the ultrastructure of H. halys spermiogenesis in both irradiated and wild males. Typical hemipteran sperm features were observed, such as mitochondrial derivative–axoneme bridges, the absence of accessory bodies, crystalline inclusions in mitochondrial derivatives, an acrosome with packed tubules, and a plaque-shaped microtubular organizing center (MTOC) in the centriolar region. Occasionally, two centrioles were observed in spermatids, with one disappearing later—a novel feature for insect spermiogenesis. In irradiated adults, cysts exhibited inconsistent radiation effects, including disorganized sperm arrangement, incomplete sperm cell divisions, multiple organelle copies within cells, failure to reabsorb cytoplasm, and a lack of axonemes. Additionally, rod-shaped viruses or virus-like particles were found in vasa deferentia, regardless of irradiation. Halyomorpha halys (Heteroptera: Pentatomidae) is an insect pest native to Asia that has spread over the last two decades to most of the North America, parts of South America, Europe and North Africa. Its impact is significant as it can feed on more than 300 host plants, rendering affected fruits and vegetable crops unsellable or of lower quality. Various chemical and biological methods have been used to control this pest, with varying degrees of success. The sterile insect technique (SIT) is a pest control method involving the sterilization of insects via ionizing radiation and their subsequent mass release into the field. In the present contribution, the spermiogenesis of H. halys was studied from an ultrastructural point of view in both irradiated and non-irradiated adult males. In both cases, we observed ultrastructural characteristics typical of hemipteran sperm cells: bridges connecting the mitochondrial derivatives and the axonemal microtubules, the absence of accessory bodies, and the presence of two or three crystalline inclusions within the mitochondrial derivatives, an acrosome composed of tightly packed tubules, and an atypical, plaque-shaped microtubular organizing center (MTOC) in the centriolar region. Moreover, in the same region, we seldom observed the presence of two centrioles in the spermatids, one of which disappeared at a later stage of maturation. This feature is a novelty for insect spermiogenesis. The cysts of irradiated adults were not all uniformly affected by the radiation. However, irradiated cysts sometimes exhibited a general disorganization of sperm arrangement, incomplete divisions of sperm cells resulting in multiple copies of the same organelle within the same cell, failure to reabsorb the cytoplasm, and the lack of axonemes. Finally, rod-shaped viruses or virus-like particles were observed in vasa deferentia independently of irradiation. [ABSTRACT FROM AUTHOR]

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]

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]

The invasive alien stink bug Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae), native to eastern‐southern Africa and central‐southern Asia, poses significant economic threats to agroecosystems due to its polyphagous diet with a preference for brassicaceous crops. Current control methods using broad‐spectrum insecticides are expensive and often result in significant negative ecological impacts, as well as posing a health risk to consumers. This study provides a detailed description of the mating behavior of B. hilaris, with the aim to ascertain whether substrate‐borne vibrations have a role in premating phases. Such knowledge may contribute to the development of alternative biorational control techniques employing vibrational strategies. Virgin adults were tested individually or in pairs on different substrates, that is, a loudspeaker membrane and a bean plant. Vibrations emitted by males and females were recorded using a laser Doppler vibrometer, and the following spectral and temporal parameters were analyzed: fundamental frequency, emission time, repetition time, and signal modulation. Three distinct types of vibration emitted by males and females were identified: a male vibrotype (MV‐1), a female vibrotype (FV), and a copula signal exclusively emitted by males (MS‐2). MV‐1 and FV were emitted prior to genitalia contact, whereas MS‐2 was emitted within the mounting and engagement phases. Statistical analysis revealed significant transitions in behavioral phases for couples that achieved mating. By analyzing the walking behavior, there was an inverse relationship between motility and signal emission when comparing the two sexes, which suggests that males might engage in a form of searching behavior. These findings provide insight into the crucial role of vibrational communication to achieve mating in B. hilaris. [ABSTRACT FROM AUTHOR]

Background: G1 strain Ganaspis brasiliensis (Ihering) has been recently released in both Europe and America as a biological control agent of the spotted wing drosophila, Drosophila suzukii (Matsumura). In initial phases of classical biological control programs, it becomes imperative to evaluate the susceptibility of parasitoids to insecticides, to identify the best alternatives to adopt in an integrated pest management and organic perspective. In this study, we evaluated lethal and sublethal effects of topical application of five different insecticides classes: neonicotinoids, diamides, pyrethroids, organophosphates and spinosyns. Additionally, we tested residual toxicity in field trials in vineyards and sweet cherry orchards., Results: Adult wasps' susceptibility to different insecticides' classes were consistent between laboratory and field. Spinosad exhibited the highest toxicity, with a median lethal concentration (LC 50 ) of 0.00372 of the maximum field dose, and the highest knock-down effect in field trials, causing 92.5 ± 5% of mortality at T 0 . λ-cyhalothrin showed sublethal effects on both male and female insects' longevity when applied at LC 30 . In field trials, deltamethrin showed the highest persistence, causing significant parasitoid mortality up to 14 days after treatment. Conversely, cyantraniliprole was the least toxic active ingredient according to both topical and residual bioassays, even though its residues caused mortality up to 7 days after the treatment in the field., Conclusion: Our results indicate that spinosad and λ-cyhalothrin are highly toxic to G. brasiliensis, making them incompatible with classical biological control programs. Cyantraniliprole exhibited lower toxicity, and may be considered a selective pesticide for the integrated management of D. suzukii. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)