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Candidate biological control agents of invasive insect pests are increasingly being found in new geographic regions as a result of unintentional introductions. However, testing the degree of genetic differentiation among adventive and native-range populations of these agents is rarely done. We used reduced-representation sequencing of genomic DNA to investigate the relationships among laboratory lines of Trissolcus japonicus (Ashmead) (Hymenoptera, Scelionidae), an egg parasitoid and biological control agent of the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera, Pentatomidae). We compared sequences from multiple adventive populations in North America (Canada, USA) and Europe (Switzerland) with populations sourced from part of its native range in China. We found considerably more genetic variation among lines sourced from adventive populations than among those within native populations. In the Pacific Northwest of North America (British Columbia, Canada and Washington State, USA), we found preliminary evidence of three distinct genetic clusters, two of which were highly dissimilar from all other lines we genotyped. In contrast, we found that other adventive lines with close geographic proximity (two from Ontario, Canada, three from Switzerland) had limited genetic variation. These findings provide a basis for testing biological differences among lines that will inform their use as biological control agents, and provide evidence to support a hypothesis of several independent introductions of T. japonicus in western North America from different source areas.

The invasive brown marmorated stink bug (BMSB) is a major insect pest that invades human structures causing nuisance issues and attacks numerous fruit and vegetable crops in Northern America. As this pest threatens $23 billion worth of specialty and agricultural crops in the U.S. and is difficult to manage due to insecticide resistance, control practices such as the use of biological control through egg parasitoid wasps are critical. In its native range of Asia, BMSB populations are controlled primarily by members of the Trissolcus genus such as the samurai wasp, but U.S. native wasps have demonstrated low success of BMSB egg parasitism. An introduced population of the samurai wasp was detected in Utah in 2019, and early research suggests this wasp may provide effective biological control of BMSB. This research focuses on the status and enhancement of the samurai wasp and native parasitoids in northern Utah. Chapter II explores the range of the exotic samurai wasp and native parasitoids in northern Utah’s urban and agricultural areas and factors affecting their prosperity. The samurai wasp exhibited a strong association with BMSB, following its patterns of seasonality, orchard groundcover preference, and reliance on urban landscape resources. Samurai wasps accounted for only a small proportion of total Trissolcus parasitoid detections, and more native wasps were captured in orchards with floral groundcover as compared to those with non-floral groundcover. Chapter III assesses the attractiveness of kairomone lures to the samurai wasp in field and laboratory conditions. In the field, samurai wasp attacked lab-reared BMSB egg masses at almost an equal rate to a native Trissolcus species but had much higher emergence success from egg masses. Laboratory trials compared specific chemical blends for attractiveness to the samurai wasp. Finally, Chapter IV investigates the role of BMSB parasitoids in a state previously unsurveyed for the samurai wasp. Reported is the first record of samurai wasp in the state of Idaho and details about its population size and geographic locations. Overall, population sizes were very low, but collection of wild egg masses proved samurai wasp is taking an active role in the suppression of BMSB populations.

Halyomorpha halys (Stål, 1855) Material examined (n=7): loc. OL4 (40°48′N, 16°56′E) 17.X.2020, 22.X.2020, 28.X.2020, 04.II.2021, 09.III.2021. Distribution: Native of Asia region (China, Japan, Korea) is currently spreading worldwide becoming an important alien pest and damaging several agricultural crops. Remarks: Recorded for the first time in Italy (Modena district) by Maistrello et al. (2013). However, it was reported few years earlier (2007) in Genoa (North Italy) (Maistrello & Dioli 2014)., Published as part of Laterza, Ilaria, Tamburini, Giovanni, Panzarino, Onofrio, Loverre, Pamela, Mastronardi, Maria Grazia, Dioli, Paride & Lillo, Enrico De, 2022, The first annotated checklist of Pentatomoidea (Hemiptera: Heteroptera) fauna of Alta Murgia National Park (Apulia region, Southern Italy), pp. 401-420 in Zootaxa 5219 (5) on page 416, DOI: 10.11646/zootaxa.5219.5.1, http://zenodo.org/record/7431348, {"references":["Maistrello, L., Dioli, P. & Bariselli, M. (2013) Trovata una cimice esotica dannosa per i frutteti. Agricoltura. 6, 67 - 68.","Maistrello, L. & Dioli, P. (2014) First record in Italian Central Alps of Halyomorpha halys (Insecta, Heteroptera, Pentatomidae). Il Naturalista valtellinese, Atti Museo civico di Storia naturale Morbegno, 25, 51 - 57"]}

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 Stal (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.

Egg parasitoids play an important role in biological control of pest species attacking and killing their hosts at an early stage of their development. During the antagonistic coevolution with their hosts, egg parasitoids have developed a great ability to locate their host using chemical cues. A considerable amount of literature is available on this topic, while nothing is known about a possible adaptation of egg parasitoids to topography and mechanical properties of egg surface features and its shape when attaching to the host egg for oviposition. In the present investigation, the attachment ability of adults of both sexes of the egg parasitoid Anastatus bifasciatus (Hymenoptera: Eupelmidae) to artificial (polishing paper, flat glass, glass beads as dummies of the host egg) and natural surfaces (eggs of Halyomorpha halys and Nezara viridula, both Heteroptera: Pentatomidae), with different roughness and wettability, was measured using centrifugal force tester and traction force experiments. The parasitoid attachment devices and the egg surfaces were examined under cryo scanning electron microscope, wettability and roughness of natural and artificial substrates were characterised. We detected differences in the attachment devices and attachment ability of the two sexes. The collected data revealed a special ability of the female to attach to the eggs of the host species, thus suggesting an adaptation of the A. bifasciatus female to the surface features of the eggs during oviposition.

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.

International audience; The brown marmorated stink bug, Halyomorpha halys, is an invasive agricultural pest of fruit trees and vegetables. Egg parasitoids play a key role in the reducing of H. halys populations. Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) can parasitize H. halys and complete its life cycle in this host species. Many factors can influence this parasitoid–host relationship. Of these factors, we evaluated the effect of female age, exposure time, and host species on the biological characteristics and fecundity of O. kuvanae reared on eggs of H. halys as well as another previously known host Philosamia ricini (Lepidoptera: Saturniidae). In this study, we used a 3‐year‐old laboratory colony of O. kuvanae. Parasitism rates positively affected by exposure time in P. ricini. The highest parasitism rates were obtained in 5‐ and 7‐day‐old females of both hosts. The highest emergence rates were recorded on P. ricini for 5‐ and 7‐day‐old female P. ricini (81.8% and 84.8%, respectively). The development time of O. kuvanae ranged from 18.4 to 19.1 days on H. halys and 17.7 to 18.3 days on P. ricini. The longevity of O. kuvanae that were provided honey was 38.5 and 47.8 days on H. halys and P. ricini, respectively. The longevity of O. kuvanae that were not provided honey was 2.3 and 2.8 days on H. halys and P. ricini, respectively. The sex ratio was male‐biased (36.5% female) on H. halys and female‐biased (55.2% female) on P. ricini. Fecundity of O. kuvanae was 37.7 and 59.6 progeny per female for H. halys and P. ricini, respectively. The performance of O. kuvanae was lower when compared with its performance on the host P. ricini. Our results suggest that O. kuvanae has potential as new biological control agent for H. halys.

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.

Methyl salicylate (MeSA) is an herbivore-induced plant volatile widely tested for attracting natural enemies for pest control. MeSA is commercially sold as slow-release lures or as a spray. While MeSA application has increased the abundance of natural enemies in numerous food crops, its ability to reduce pests for crop protection is not as frequently demonstrated. Our first objective was to test MeSA lures in ornamental fields where few studies have been done, and monitor natural enemies, pests, and crop protection. A 2-year study in spruce container yards revealed more aphid parasitoids (Pseudopraon sp.), fewer aphids (Mindarus obliquus) on shoot tips, and less shoot tip damage in MeSA plots during the first year. A 2-year study in red maple fields revealed more predatory lady beetles and rove beetles, and parasitic Ceraphronidae, Diapriidae, and Chalcidoidea in one or both years with MeSA. Fewer pest thrips were also captured in MeSA plots, though it is not clear whether this was due to enhanced predation or reduced colonization. Maple growth as measured by stem diameter change did not differ with MeSA use. A 2-year study examining predation on sentinel Halyomorpha halys eggs in various mature ornamental stock blocks found no increase in predation except for 1 month, though green lacewings, lady beetles, and predatory thrips occurred more in MeSA plots in the first year. While MeSA is expected to enhance biological control by herding in natural enemies, the impacts that applied volatiles have on predator efficiency is mostly unknown. Thus, our second objective examined how volatiles would impact feeding rates at close-range. Adult carabid Pterostichus melanarius, adult coccinellids Coccinella septempunctata and Harmonia axyridis, and larval lacewing Chrysoperla rufilabris consumed their prey at similar rates in the presence/absence of MeSA when food was presented directly in a 28 cm2 or 30 ml arena, or when foraging in a 520 cm2 outdoor soil arena or 946 ml arena with aphids on leaves.

������������������ �������������������� �������������������� ������������������ �������������� ���������������������������� ���������������������� ������������������ ������������������-�������������������� ���������� (Halyomorpha halys, St��l, 1855), ���������������������������� �� �������������������������������� ���� �������������������������� ������������ ������������������ ����������������. �������������� �������� �������������� �������������� �������� �� ���������� ������������������-�������������������� ���������� �� �������������� ������ �������������������� ������������������ �������������������������������� ������������������ �� 12 ���� 24-48 ���� �������������������������� �������������� ��������������������. �������������������������� �������������������� �������������� ������ ������������������ ������������ �� �� ���������� ���������������� ������������������ �������������� ������������������, �������������� �� ���������������� ��������, ���������� ������������������ �������������� ������������ �� ���������������� ���� ������������������-���������������� ������������ ���� ���������� ����������, ������ ���������������� �������������������� ������������������-�������������������� ����������, ������������ �������������� �� ���������� ���� ��������������., The article presents results of a 2-year study of the first Russian-produced pheromone preparation of the brown marmorated stink bug (Halyomorpha halys, St��l, 1855) that was developed and synthesized at the All-Russian Plant Quarantine Center. An increase in the frequency of catching nymphs and adults of the brown marmorated stinks bug in traps is shown along with an increase in the dose of the synthesized preparation from 12 to 24-48 mg, the efficiency of traps increases. The use of pheromone traps for mass trapping and pest control should be carried out from mid-summer, when the pest actively flies and feeds on host plants until the end of autumn, when the mass aggregation of the brown marmorated stink bug, searching for shelters and wintering occurs.

The brown marmorated stink bug (Halyomorpha halys) is a pest found on agricultural crops, first reported in Bulgaria in 2016. In 2018 in the region of Plovdiv it was found feeding on a variety of agricultural and ornamental plants, such as corn, tomato, apple, vinegrapes, raspberry, mulberry, and hibiscus. The rapid spread and the threat for many potential host plants in Bulgaria were the reasons for the current study. The life cycle parameters of the Bulgarian population of H. halys were studied in 2019. The progeny of the field-collected adults from the region of Plovdiv were reared at laboratory conditions at constant temperature of 25 ± 2°C, RH 60 - 70% and a photoperiod of 16:8 hours L:D. Under these conditions the embryonic development was completed in 5.10 ± 1.02 days; the 1st nymphal instar in 5.32 ± 1.23 days; the 2nd - in 9.35 ± 2.88 days; the 3rd - in 7.18 ± 2.55 days; the 4th - in 7.40 ± 1.89 days, and for the 5th nymphal instar – in 10.87 ± 2.63 days. The adults lived an average of 17.53 ± 9.34 days with a maximum life span of 44 days

Halyomorpha halys (Stål, 1855) —Brown Marmorated Stink Bug (Fig. 6) Distribution in Turkey (Map 6): Artvin, Giresun, İstanbul, İzmir, Ordu, Rize, Samsun, Trabzon, Yalova (Çerçi & Koçak 2017; Güncan & Gümüş 2019; Ak et al. 2019; Cianferoni et al. 2019, Göktürk & Tozlu 2019, Çerçi 2021; Özdemir & Tuncer 2021); Ankara, Aydın, Bartın, Bursa, Eskişehir (this study). New records by citizen scientists in Turkey: 1. Ankara: Çankaya, 23.XI.2020 (GBIF.org 2021). 2. Artvin: Borçka, 28.VII.2019 (Bacak, 2019a). 3. Aydın: Kuşadası, 03.X.2020 (Oruz, 2020d). 4. Bartın (centre), 22.X.2020 (Amaç, 2020b). 5. Bursa: Nilüfer, 29.IX.2018 (Biçici, 2018d); 6. Nilüfer, 27.VII.2019 (GBIF.org 2021). 7. Eskişehir, 10.VIII.2020 (GBIF.org 2021). 8. İstanbul: Adalar, 19.IX.2019 (Kernane 2019); 9. Ataşehir, 3.X.2020 (GBIF.org 2021); 10. Beşiktaş, 1.VI.2019 (Grommen 2019a); 11. Beşiktaş, 27.X.2020 (Kılıç 2020); 12. Beyoğlu, 12.VIII.2019 (Grommen 2019b); 13. Fatih, 29.VIII.2019 (GBIF.org 2021); 14. Kadıköy, 05.X.2019 (Çelebi 2019); 15. Kadıköy, 13.XI.2019 (Uludağ 2019); 16. Kadıköy, 29.X.2020 (Sipahioğlu 2020); 17. Kadıköy, 30.VIII.2020 (GBIF.org 2021); 18. Kadıköy, Caferağa, 23.IX.2018 (GBIF.org 2021); 19. Kartal, 24.IX.2020 (GBIF.org 2021); 20. Küçükçekmece, 7.X.2020 (Usta 2020); 21. Kadıköy, Maltepe, 10.VIII.2020 (Coşkun, 2020e); 22. Sarıyer, 24.II.2021 (GBIF.org 2021); 23. Sarıyer, 20.VIII.2019 (GBIF.org 2021); 24. Sarıyer, 6.X.2020 (Evans 2020); 25. Üsküdar, 19.X.2019 (Öztürk 2019); 26. Üsküdar, Altunizade, 27.I.2020 (GBIF.org 2021); 27. Üsküdar, Küçük Çamlıca, 9.IV.2021 (Wak 2021). 28. İzmir (Konak), 7.IX.2020 (GBIF.org 2021); 29. Konak, 27.X.2020 (GBIF.org 2021). 30. Rize: Derepazarı, Tersane, 27.VII.2020 (Karataş 2020). 31. Trabzon (centre), 04.X.2019 (GBIF.org 2021). Comments: H. halys is native in East Asia and ranges in China, Japan, Korea and Taiwan (Rabitsch 2008). It is found firstly in North America and Chile as an invasive insect species. This bug was introduced to Europe in 2004 for the first time and spread to many European countries including Austria, Croatia, Germany, France, Hungary, Italy, Liechtenstein, Romania, Russia, Serbia, Switzerland, Slovakia, Slovenia, Spain, and Sweden (Cianferoni et al. 2018). It was recorded from Greece in 2011, from Georgia in 2015 and from Bulgaria in 2016 (Cianferoni et al. 2018; Özdemir & Tuncer 2021; Çerçi 2021). Following these records from neighbouring countries, it arrived in Turkey and it was firstly discovered in İstanbul in 2017 (Çerçi & Koçak 2017). According to the records given later, the oldest record in Turkey is from Artvin in 2016 (Göktürk & Tozlu 2019). It seems, from these records, that this species spread to Turkey both from Georgia through Artvin and from Europe through İstanbul. According to new data, H. halys can be found year-round, but it is most common in autumn. Eleven of the 31 records were reported in October (Graph 6). GRAPH 6. Seasonality of Halyomorpha halys (Stål, 1855), based on records from Turkey., Published as part of Çerçi, Bariş, Karataş, Ahmet & Karataş, Ayşegül, 2021, Insecta non gratae: New Distribution Records of Eight Alien Bug (Hemiptera) Species in Turkey with Contributions of Citizen Science, pp. 1-28 in Zootaxa 5057 (1) on pages 12-13, DOI: 10.11646/zootaxa.5057.1.1, http://zenodo.org/record/5585486, {"references":["Cerci, B. & Kocak, O. (2017) Further contribution to the Heteroptera (Hemiptera) fauna of Turkey with a new synonymy. Acta Biologica Turcica, 30, 121 - 127.","Guncan, A. & Gumus, E. (2019) Brown marmorated stink bug, Halyomorpha halys (Stal, 1855) (Hemiptera: Heteroptera, Pentatomidae), a new and important pest in Turkey. Entomological News, 128 (2), 204 - 210. https: // doi. org / 10.3157 / 021.128.0208","Ak, K., Uluca, M., Aydin, O. & Gokturk, T. (2019) Important invasive species and its pest status in Turkey: Halyomorpha halys","Cianferoni, F., Graziani, F. & Ceccolini, F. (2019) The unstoppable march of Halyomorpha halys: new first country records (Hemiptera: Heteroptera), Spixiana, 42 (1), 60.","Gokturk, T. & Tozlu, G. (2019) An important agricultural pest for Turkey: invasive species Halyomorpha halys. Proceedings of International Black Sea Coastline Countries Symposium, Batumi / Georgia, 2 - 5 May 2019, 283 - 297. [in Turkish]","Cerci, B. (2021) First record of Halyomorpha halys (Stal, 1855) (Pentatomidae: Heteroptera) in Aegean Region of Turkey. Acta Biologica Turcica, 34 (1), 35 - 37.","Ozdemir, I. O. & Tuncer, C. (2021) A new invasive polyphagous pest in Turkey, Brown Marmorated Stink Bug [Halyomorpha halys (Stal, 1855) (Hemiptera: Pentatomidae)]: identification, similar species and current status. Black Sea Journal of Engineering and Science, 4 (2), 58 - 67. [in Turkish] https: // doi. org / 10.34248 / bsengineering. 844095","Bacak, E. (2019 a) Dogal Hayat Observation Sharing Platform. 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Available from: https: // www. inaturalist. org / observations / 64847488 (accessed 8 September 2021)","Evans, C. (2020) iNaturalist Research Grade Observations. Available from: https: // www. inaturalist. org / observations / 64628875 (accessed 9 July 2021)","Ozturk, C. N. (2019) iNaturalist Research Grade Observations. Available from: https: // www. inaturalist. org / observations / 17876085 (accessed 9 July 2021)","Wak (2021) iNaturalist Research Grade Observations. Available from: https: // www. inaturalist. org / observations / 73594352 (accessed 9 July 2021)","Karatas, A., Karatas, A., Yavuz, N. & Genc, M. (2020) Distribution and activity period of the invasive Orosanga japonica (Melichar, 1898) (Hemiptera: Ricaniidae) in Turkey. Zoology in the Middle East, 66 (3), 246 - 252. https: // doi. org / 10.1080 / 09397140.2020.1793502","Rabitsch, W. (2008) Alien True Bugs of Europe (Insecta: Hemiptera: Heteroptera). Zootaxa, 1827 (1), 1 - 44. https: // doi. org / 10.11646 / zootaxa. 1827.1.1","Cianferoni, F., Graziani, F., Dioli, P. & Ceccolini, F. (2018) Review of the occurrence of Halyomorpha halys (Hemiptera: Heteroptera: Pentatomidae) in Italy, with an uptake of its European and World distribution. Biologia, 73, 599 - 607. https: // doi. org / 10.2478 / s 11756 - 018 - 0067 - 9"]}

Heat waves are becoming more frequent with climate change, and their impact on lower and higher trophic levels can differ. Higher trophic levels, such as predators and parasitoids, are predicted to be more strongly affected by heat waves than herbivores because they may have smaller thermal windows and because of altered ecological interactions with lower trophic levels. We tested the effects of heat waves of varying intensity (36–42°C), imposed for 4 h during five consecutive days on the egg stage of an invasive herbivore, the brown marmorated stink bug (Halyomorpha halys), and on various developmental stages of its parasitoid, Trissolcus japonicus. Halyomorpha halys eggs had lower hatching success and fewer nymphs emerging with increasing intensity of heat stress, while exposure during the egg and larval stages of T. japonicus did not decrease adult emergence rates. Heat waves increased developmental time of parasitoids and decreased adult emergence when pupal stages were exposed. Adult parasitoids experiencing heat stress had lower survival, but their parasitism success overall was not affected. In addition, we detected transgenerational effects, whereas emergence success and the number of adult parasitoids emerging in the second generation declined when the parental generation was exposed to 42°C. Contrary to expectations, the results suggest that H. halys may be more sensitive to heat stress than T. japonicus, at least during early development. Our findings indicate that biological control services provided by T. japonicus can be maintained in the face of increasing heat wave events and point to the importance of following populations beyond the first generation to better understand the long‐term consequences of heat stress.

Simple Summary The brown marmorated stink bug (BMSB) is a polyphagous species that causes severe damage to tree fruit, small fruit, vegetables, ornamental crops, and field crops. Classical biological control is one potential long-term and low-cost strategy to control the BMSB, using natural enemies. However, no natural enemy native to Greece that infects BMSB has been reported yet. Herein, we report the occurrence of two native hymenopteran egg parasitoids—Anastatus bifasciatus and Ooencyrtus telenomicida. Both egg parasitoids were collected from egg masses of the BMSB in the region of Thessaloniki, northern Greece. The total parasitism rate was 8.5%. Furthermore, A. bifasciatus was collected in mid-June and mid-August on egg masses of BMSB that were laid on green beans, apricots, and olives. On the other hand, O. telenomicida was only collected in mid-June, on one egg mass of BMSB that was laid on apricots. This first record could actually facilitate, for future tasks, the biological control of H. halys in Greece. Abstract Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an endemic species of East Asia; it was introduced into Europe in 2007. It has a wide range of hosts as it feeds on over 170 host plant species and significantly impacts crop production. In Greece, H. halys causes significant losses in the production of kiwi, peaches, and green beans; thus, control of this species (including biological control) is essential. Here, we focus on the potential impact of native natural enemies of H. halys in Greece. From June to October 2020, we sampled naturally field-laid H. halys egg masses to recover native parasitoids. A total of 20 egg masses of H. halys were collected from infested fields from different locations in northern Greece. Out of 529 eggs, 45 parasitoids managed to hatch successfully. The overall parasitism rate was 8.5%. We found two species of Hymenopteran egg parasitoids attacking H. halys eggs—Anastatus bifasciatus (Geoffrey) (Hymenoptera: Eupelmidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), with the former comprising 58% of all parasitoids that were recovered. These results contribute to the knowledge about the natural enemy community that attacks H. halys in Greece, and the use of these native egg parasitoids in biological control programs may be a viable H. halys management strategy.

Simple Summary The brown marmorated stink bug Halyomorpha halys has become a serious invasive species in Northern America and Europe, where it causes major damage to a wide range of crops. Understanding the ecology and behaviour of this pest is key to identifying the most effective strategies to contain its spread. Here we demonstrate that microclimate conditions affect H. halys water loss and that transpiration is influenced by feeding regime and sex. In the overwintering generation, transpiration does not seem influenced by population density and the first nutritional need of individuals exiting diapause is represented by hydration, likely due to water loss during the diapause. Our data suggest that hot and dry climates are not favourable for H. halys and may limit its geographical range. Similarly, microclimatic conditions within crops may have a significant impact on the distribution of H. halys and insect activity may be affected by crop management practices (e.g., pruning and irrigation). Abstract Understanding the interaction between insects and microclimate can be essential in order to plan informed and efficient treatments against agricultural pests. Microclimatic factors such as humidity and temperature can influence the population dynamics of the invasive agricultural pest Halyomorpha halys, the brown marmorated stink bug. The aim of this work was to evaluate the level of transpiration of H. halys in dry, normal and humid microclimates according to the sex, physiological conditions and developmental stage of individuals. Water loss during diapause and the effect of population density on insects’ transpiration were also assessed, as were the nutritional preferences of adults upon exiting diapause. Our data demonstrate that microclimatic conditions significantly influence the transpiration of this pest species. The effect of sex and feeding status on insects’ water loss is marked, while population density does not influence water loss in diapausing individuals. The first nutritional need of the overwintering generations is represented by hydration, likely due to the water loss during diapause.

Olives ripen in the late autumn and represent a good source of nutrients that Halyomorpha halys uses to prepare for diapause. This is the first study to investigate the impact of H. halys infestation on the phenolic response and olive fruit quality in the pierced tissue of damaged fruits and in the non-pierced part of damaged fruits of ‘Istrska belica’ and ‘Pendolino’ cultivars. Both total phenolic content and antioxidant capacity contents significantly increased in the infested fruits of the cultivar ‘Istrska belica’. Total phenolic content in the pierced tissue of damaged fruits increased by 10.7%, while the content of AC in the non-pierced tissue of damaged fruits increased by 7.11% and in the pierced tissue of damaged fruits by 6.1% compared to control. A total of 44 individual phenolic compounds were identified, 21 of them increased in at least one cultivar after infestation. Huge increases in phenolic content were observed in both cultivars, particularly for flavones, secoiridoids, anthocyanins, and flavonols in the pierced tissue of damaged fruits. The most responsive individual phenolic compound in both cultivars was oleuropein. Its content in the pierced tissue of damaged fruits increased by 44.7% in the cultivar ‘Pendolino’ and for 82.6% in the cultivar ‘Istrska belica’.

Chemosensory proteins (CSPs) have been identified in the sensory tissues of various insect species and are believed to be involved in chemical communication in insects. However, the physiological roles of CSPs in Halyomorpha halys, a highly invasive insect species, are rarely reported. Here, we focused on one of the antennal CSPs (HhalCSP15) and determined whether it was involved in olfactory perception. Reverse transcription PCR (RT-PCR) and quantitative real-time PCR (qRT-PCR) analysis showed that HhalCSP15 was enriched in nymph and male and female adult antennae, indicating its possible involvement in the chemosensory process. Fluorescence competitive binding assays revealed that three of 43 natural compounds showed binding abilities with HhalCSP15, including β-ionone (Ki=11.9±0.6μM), cis-3-hexen-1-yl benzoate (Ki=10.5±0.4μM), and methyl (2E,4E,6Z)-decatrienoate (EEZ-MDT; Ki=9.6±0.8μM). Docking analysis supported the experimental affinity for the three ligands. Additionally, the electrophysiological activities of the three ligands were further confirmed using electroantennography (EAG). EEZ-MDT is particularly interesting, as it serves as a kairomone when H. halys forages for host plants. We therefore conclude that HhalCSP15 might be involved in the detection of host-related volatiles. Our data provide a basis for further investigation of the physiological roles of CSPs in H. halys, and extend the olfactory function of CSPs in stink bugs.

Facultative winter adult diapause in Halyomorpha halys is regulated by a long-day photoperiodic response. Day length also influences nymphal development, which slows down at the critical (near-threshold) day lengths. We compared the photoperiodic responses of one native (Andong, South Korea) and three invasive (Torino, Italy; Basel, Switzerland; and Sochi, Russia) populations in a laboratory common-garden experiment. Nymphs developed and emerging adults were reared at 24 °C in a range of photoperiods with day lengths of 14.0, 14.5, 15.0, 15.5, and 16.0 h. The critical day lengths of the photoperiodic responses of both sexes fell between 14.5 and 15.0 h in the native Korean population and between 15.0 and 15.5 h in three invasive European populations. The differences between the three invasive populations were not significant, despite their distant origins. Moreover, the difference between the Korean and European populations was much smaller than was expected. The microevolution was possibly ‘too slow to keep up’ with the rapid spread of the invader across Eurasia. It is expected that soon the critical day length of the invasive H. halys populations will gradually change to adapt better to local conditions. At present, the critical day length for diapause induction of 15 h 15 min can be used to model the phenology, further spread, and response to climate change for all European populations of the pest.

Simple Summary The brown marmorated stinkbug Halyomorpha halys, is an invasive pest that causes millions of dollars of crop damage each year in the US. A promising biocontrol agent for this pest is the samurai wasp, Trissolcus japonicus, which is a potential long term control method with few negative ecological impacts. However, the wasps’ small size of only 1 mm in length can make it difficult to identify morphologically. We developed a DNA-based approach to determine whether a wasp specimen is T. japonicus using conventional methods of DNA extraction, PCR, and gel electrophoresis. When tested against eight families of Hymenoptera, including three Trissolcus species, our method identified samurai wasp samples with 100% accuracy. Additionally, in silico analyses of various T. japonicus sequences provide evidence that the method will work throughout the US, Europe, and parts of Asia. We expect that this method will be a valuable tool for reliably identifying T. japonicus during distribution and recapture efforts to assess its survival, establishment, and dispersal for biocontrol purposes. Abstract The samurai wasp, Trissolcus japonicus (Ashmead), has been proposed as a biocontrol agent against brown marmorated stink bugs (BMSB), due to its ability to parasitize and kill BMSB eggs. However, the wasps’ small size makes it challenging for those untrained in morphological identification to determine the wasps’ species. To circumvent this problem, a molecular method was created to identify T. japonicus. The method uses species-specific primers, designed in this study, which target the variable region of the mitochondrial Cytochrome Oxidase 1 (CO1) locus. After confirming successful DNA extraction from samples, the PCR amplification using our primers produced 227-bp PCR products for all T. japonicus specimens and no amplification in other microhymenoptera candidates. Additionally, DNA from BMSB-parasitized eggs gave positive PCR amplification, while the control BMSB samples showed no amplification. This indicates that PCR with our primers specifically and sensitively differentiates T. japonicus specimens from other similar wasp species and discriminates between T. japonicus-parasitized and non-parasitized BMSB eggs. Finally, an in silico analysis of CO1 sequences demonstrated that our primers match the sequences of four different haplotypes of T. japonicus, indicating that our diagnostic method could potentially be applied to analyze T. japonicus populations throughout North America, Europe, and parts of Asia.

Simple Summary Halyomorpha halys, the brown marmorated stink bug (BMSB), is an invasive pest causing serious damage to agricultural production. Managing this pest species is challenging because of its wide host range and lack of effective control measures. Biological control of H. halys through natural enemies seems to be the most environmentally friendly and sustainable solution. Extensive knowledge of the native egg parasitoid fauna is needed prior to the introduction of a biological control program. The main purpose of the study, carried out in the Goriška region of Western Slovenia, was to detect egg parasitoid species associated with H. halys and to evaluate their impact on the pest population under local environmental conditions. High species richness was identified during the study, and five egg-parasitoids were recorded for the first time in Slovenia. The native species Anastatus bifasciatus dominated in urban and suburban areas, while the non-native Trissolcus mitsukurii prevailed in agricultural areas. Rapid recruitment of native parasitoids, the presence of an effective alien parasitoid species in the region and increasing overall parasitism rates are very encouraging results and valuable information for future activities regarding the biological control of H. halys in Slovenia. Abstract Halyomorpha halys (Hemiptera: Pentatomidae), native to East Asia, has become a globally invasive pest, as a serious threat to agricultural production and a notorious nuisance pest in urban areas. Considerable efforts have been made so far to develop effective pest control measures to prevent crop damage. Biological control of this invasive stink bug by egg parasitoids has proven to be the most environmentally sustainable long-term solution. Knowledge of the native egg parasitoid fauna is of key importance when implementing a biological control program. Therefore, the main objective of our study was to detect egg parasitoid species associated with H. halys in the Goriška region (Western Slovenia) and to evaluate their impact on the pest population under field conditions. In the years 2019 and 2020, around 4600 H. halys eggs were collected in the wild and more than 3400 sentinel eggs were exposed to detect parasitoids in the field. Five egg-parasitoid species emerged from H. halys eggs: Anastatus bifasciatus (Hymenoptera: Eupelmidae), Telenomus sp., Trissolcus basalis, Trissolcus mitsukurii (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Hymenoptera: Encyrtidae), all of them are new records for Slovenia. The native species, An. bifasciatus, dominated in urban and suburban areas, while non-native Tr. mitsukurii prevailed in agricultural areas. Overall parasitism rates of naturally laid eggs by the parasitoid species complex in 2019 and 2020 was 3.0 and 14.4%, respectively. Rapid recruitment of native parasitoids, early detection of an effective alien parasitoid species and increasing overall parasitism rates are very encouraging results, which need to be followed and verified in future research.

Simple Summary The brown marmorated stink bug, Halyomorpha halys, is an invasive pest species of global economic importance. It has a very broad host range and causes severe damages in agricultural, horticultural, and fruit crops. Control measures, including available chemical and mechanical options, have often proved insufficient. Surveys of natural enemies in the newly invaded areas have also shown that natural biological control is generally too low to control H. halys populations in the long run. In its native Asian range, egg parasitoids in the genus Trissolcus play an important role in controlling H. halys. Since the mid-2010s, adventive populations of Trissolcus japonicus, a dominant egg parasitoid of H. halys in Asia with a narrow host range, have been reported from several countries with prior establishment of H. halys. Here, we report the first discovery of T. japonicus in Germany. This finding corroborates a northbound expansion of the range of T. japonicus in Europe, along with H. halys. Abstract The brown marmorated stink bug, Halyomorpha halys, is a polyphagous pest species of worldwide economic importance. Since the mid-1990s, it has invaded and become established in various countries outside its native Asian range. In the newly invaded areas, biological control by native natural enemies has been shown to be insufficient in the long-term control of this severe pest. Adventive populations of Trissolcus japonicus, an important biological control agent of H. halys in Asia, have been reported from North America and some European countries since the mid-2010s. This egg parasitoid species seems to follow in the wake of the establishment of H. halys populations outside their native Asian range. Here, we report the first discovery of an adventive population of T. japonicus in Germany. In 2020, adult T. japonicus were recovered from parasitized H. halys egg masses (naturally laid and sentinel egg masses) and collected in ruderal areas using an insect suction sampler. The arrival of T. japonicus in Germany, unintentional through pathways yet unknown, corroborates a northbound expansion of its range within Europe. Further field surveys will show the extent of its dispersal and establishment capacities within this new distribution area.

Simple Summary Acroclisoides sinicus is a pteromalid of Asian origin that has recently been detected in Europe and North America. It has been frequently found in association with several scelionid and eupelmid primary parasitoids of hemipteran eggs, including the brown marmorated stink bug Halyomorpha halys, leading us to suspect that A. sinicus is an obligate or facultative hyperparasitoid. Laboratory tests were conducted using pentatomid egg masses (H. halys, Acrosternum heegeri, and Dolycoris baccarum) parasitized by primary parasitoids, including Trissolcus japonicus, Trissolcus mitsukurii, Telenomus sp., Anastatus bifasciatus, and unparasitized H. halys egg masses, to test this hypothesis. Our studies confirmed that A. sinicus is an obligate hyperparasitoid of the pupal stage of scelionid primary parasitoids but not of eupelmid ones, at least under the tested conditions. Abstract Acroclisoides sinicus (Hymenoptera: Pteromalidae) was described in 1988 from China, but recent findings in Europe and North America within the framework of Halyomorpha halys (Hemiptera: Pentatomidae) biological control indicate a Holarctic distribution. The few records and fragmented information on A. sinicus are derived from generic observations of other species belonging to the same genus, and its biological and ethological traits are still completely unexplored. It was suspected to be a facultative or obligate hyperparasitoid of many egg parasitoid species (e.g., Scelionidae and Eupelmidae), especially those parasitizing Pentatomidae eggs. Laboratory colonies of A. sinicus were established from specimens collected in the field in Europe and the USA, which allowed us to investigate for the first time the life traits of this somewhat enigmatic species. Our studies confirmed the obligate hyperparasitoid hypothesis for species of Scelionidae but not of Eupelmidae. Laboratory studies revealed that A. sinicus is extremely selective in its host recognition as only the pupal stage of its host species is exploited for parasitization. Taking into consideration its hyperparasitoid habit, the adventive A. sinicus populations in Europe and North America may potentially be severe threats to pentatomid natural control as new components in the trophic chain of pentatomids and their parasitoid guilds.

Simple Summary Trissolcus japonicus, an important natural enemy of brown marmorated stink bug in Asia, was first detected in the USA in 2014. To investigate when and where T. japonicus is found in the field, yellow sticky traps were deployed in the canopy of tree of heaven growing at the edge of small isolated patches, windbreaks, and woodlots in 2018 and 2019. In both years, captures occurred from May to September, with peaks in July and August. Captures of T. japonicus were recorded from all three habitats but were not consistently associated with a particular habit. In 2017 and 2018, T. japonicus captures were compared between tree of heaven paired with several other H. halys host trees growing at the woods edge, and in 2019, captures in tree of heaven, black walnut, and black locust growing in the same windbreaks were compared. Trissolcus japonicus and several native H. halys parasitoids were captured in all hosts, but there was not a consistent effect of host tree species on T. japonicus captures. These results can be used to inform and optimize future surveillance efforts for detecting T. japonicus as it continues to expand its range in the USA. Abstract Trissolcus japonicus, an important egg parasitoid of Halyomorpha halys in Asia, was first detected in the USA in 2014. To evaluate the effect of habitat and the seasonality of T. japonicus detections in the USA, yellow sticky traps were placed in the canopy of Ailanthus altissima growing at the edge of isolated patches of trees, windbreaks, and woodlots in northern Virginia in 2018 and 2019. In both years, captures occurred from May to September, and peaked in July and August. While T. japonicus was detected in all habitats, there was not a consistent effect of habitat type on capture frequency. To evaluate tree species effects on T. japonicus captures, in 2017 and 2018, yellow sticky traps deployed in the canopy of A. altissima bordering apple orchards were paired with a nearby trap in one of several wild tree species along a common woods edge. In 2019, these traps were deployed in A. altissima, black walnut, and black locust growing in the same windbreaks. No consistent association between captures of T. japonicus or native parasitoids of H. halys and the tree species sampled was observed among years. Results are discussed in relation to the ecology and sampling optimization of T. japonicus.

Simple Summary Halyomorpha halys (Hemiptera: Pentatomidae) is a well-known invasive pest that feeds on plant and fruit tissues. Despite numerous studies on egg parasitoids of H. halys, the natural enemies of the nymphs and adults remain poorly known. In this paper, we surveyed the parasitoids of adult H. halys by collecting overwintering H. halys populations. Our results showed that Pentatomophaga latifascia (Diptera: Tachinidae) had laid eggs on the surface of adult H. halys, and the hatched larvae of P. latifascia then penetrated the host body and fed internally to complete their development. The average parasitism rate of P. latifascia on H. halys was 2.42%. These results add an important piece of knowledge about the natural enemy community attacking H. halys in its native range and may have useful implications for biological control in the newly invaded areas. Abstract Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is a serious pest in agriculture and forests, as both adults and nymphs feed by piercing the surface of the plant and fruit tissues, causing damage. The eggs of H. halys are commonly attacked by parasitoids, however, the nymph and the adult are rarely attacked by natural enemies. We surveyed the parasitoids of adult H. halys by collecting samples from overwintering populations at three different locations and checked their body surfaces for the presence of tachinid eggs. Any host adults carrying tachinid eggs were reared in a cage for further species identification. We found that the eggs of Pentatomophaga latifascia (Villeneuve) (Diptera: Tachinidae) were laid on the surface of H. halys, and the hatched larvae penetrated the host body and fed internally to develop. The last larval instar emerged from the host to develop into pupae, killing the host in the process. According to the field survey, the average parasitism of H. halys by P. latifascia was 2.42%. The parasitoids of adult H. halys in their native range have so far been little studied and may provide a complementary component of egg parasitoids for biological control against H. halys in invaded areas.

The brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), is a serious agricultural and urban pest that has become an invasive species in many parts of the world. Olfaction plays an indispensable role in regulating insect behaviors, such as host plant location, partners searching, and avoidance of predators. In this study, we sequenced and analyzed the antennal transcriptomes of both male and female adults of H. halys to better understand the olfactory mechanisms in this species. A total of 241 candidate chemosensory genes were identified, including 138 odorant receptors (ORs), 24 ionotropic receptors (IRs), 15 gustatory receptors (GRs), 44 odorant-binding proteins (OBPs), 17 chemosensory proteins (CSPs), and three sensory neuron membrane proteins (SNMPs). The results of semi-quantitative reverse transcription PCR (RT-PCR) assays showed that some HhalOBP and HhalCSP genes have tissue-specific and sex-biased expression patterns. Our results provide an insight into the molecular mechanisms of the olfactory system in H. halys and identify potential novel targets for pest control strategies.

The brown marmorated stink bug, Halyomorpha halys, is an invasive hemipteran that causes significant economic losses to various agricultural products around the world. Recently, the pyrokinin and capa genes that express multiple neuropeptides were described in this species. Here we report six pyrokinin and capa GPCRs including two splice variants, and evaluate their (a) ability to respond to neuropeptides in cell-based assays, and (b) expression levels by RT-PCR. Functional studies revealed that the H. halys pyrokinin receptor-1 (HalhaPK-R1a & b) responded to the pyrokinin 2 (PK2) type peptide. RT-PCR results revealed that these receptors had little or no expression in the tissues tested, including the whole body, central nervous system, midgut, Malpighian tubules, and reproductive organs of males and females. HalhaPK-R2 showed the strongest response to PK2 peptides and a moderate response to pyrokinin 1 (PK1) type peptides (= DH, diapause hormone), and was expressed in all tissues tested. HalhaPK-R3a & b responded to both PK1 and PK2 peptides. Their gene expression was restricted mostly to the central nervous system and Malpighian tubules. All PK receptors were dominantly expressed in the fifth nymph. HalhaCAPA-R responded specifically to CAPA-PVK peptides (PVK1 and PVK2), and was highly expressed in the Malpighian tubules with low to moderate expression in other tissues, and life stages. Of the six GPCRs, HalhaPK-R3b showed the strongest response to PK1. Our experiments associated the following peptide ligands to the six GPCRs: HalhaPK-R1a & b and HalhaPK-R2 are activated by PK2 peptides, HalhaPK-R3a & b are activated by PK1 (= DH) peptides, and HalhaCAPA-R is activated by PVK peptides. These results pave the way for investigations into the biological functions of H. halys PK and CAPA peptides, and possible species-specific management of H. halys.

Stink bugs, including native brown stink bug (Euschistus servus) and invasive brown marmorated stink bug (Halyomorpha halys), cause damage to a variety of crops including field corn (Zea mays). Frequency and size of stink bug infestations have increased in corn fields in the Mid-Atlantic U.S., and there are growing concerns that these infestations may contribute to reductions in grain quality including increased mycotoxin concentrations. Prior research on native and invasive stink bugs has focused on understanding their biology, the damage they cause, and elucidating effective and economic management strategies. However, few studies examined the potential for stink bugs to facilitate fungal infection and mycotoxin contamination of corn grain. Thus, the objectives of this research were to: 1) assess the relationship between invasive brown marmorated stink bug (H. halys) feeding injuries and fumonisin contamination of field corn in the Mid-Atlantic U.S., 2) determine if stink bugs are a vector for mycotoxigenic Fusarium spp. in corn, and 3) evaluate the efficacy of pesticides for mitigating stink bug feeding injury and associated mycotoxin contamination in field corn. A correlation between H. halys feeding injury and fumonisin concentrations was identified, and the ability of H. halys to increase F. verticillioides infection and fumonisin concentrations in corn was demonstrated in field experiments. Fusarium species including fumonisin-producing F. verticillioides and F. proliferatum were isolated from field-collected stink bugs, and in laboratory experiments, E. servus was able to transmit F. verticillioides to non-infected corn ears after feeding on F. verticillioides-infected corn. In field studies, both fungicide and insecticide reduced stink bug-associated mycotoxin concentrations in corn, but levels of control were inconsistent. Thus, additional tactics that target both the stink bug and Fusarium should be implemented to mitigate risks of mycotoxin contamination in corn. Doctor of Philosophy Native and invasive stink bugs can severely damage crops including field corn. Frequency and size of stink bug infestations in Mid-Atlantic U.S. corn fields have increased, and there is growing concern that this may contribute to reductions in grain quality. Insect feeding injury is a risk factor for fungal infection and mycotoxin contamination in corn. Mycotoxins are toxic chemicals produced by certain fungi that have detrimental health effects on animals including livestock and humans. The relationship between stink bug feeding injuries and mycotoxin contamination in corn grain is not well understood, and management strategies to minimize the risk of mycotoxin contamination in corn need to be identified. The main goal of this research was to characterize interactions between stink bugs and mycotoxin-producing fungi and identify tactics for controlling both the insect pest and pathogen. Specific objectives were to: 1) assess the relationship between invasive brown marmorated stink bug (H. halys) feeding injuries and fumonisin contamination of field corn in the Mid-Atlantic U.S., 2) determine if stink bugs are a vector for mycotoxin-producing Fusarium spp. in corn, and 3) evaluate the efficacy of pesticides for mitigating stink bug feeding injury and associated mycotoxin contamination in field corn. Results from this work indicated that stink bugs have the ability to cause feeding injuries which facilitate invasion of mycotoxin-producing Fusarium species, leading to increases in mycotoxin concentrations in corn grain. Studies also demonstrated that stink bugs can vector Fusarium species during feeding and increase Fusarium infection of corn resulting in subsequent mycotoxin contamination. Field studies indicated that pesticide applications targeting both the stink bugs and mycotoxigenic fungi may be needed to minimize risk of mycotoxin contamination in corn. However, under low pest pressure, application of pesticides is unlikely to be profitable.

The brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), is a serious agricultural and urban pest that has become an invasive species in many parts of the world. Olfaction plays an indispensable role in regulating insect behaviors, such as host plant location, partners searching, and avoidance of predators. In this study, we sequenced and analyzed the antennal transcriptomes of both male and female adults of H. halys to better understand the olfactory mechanisms in this species. A total of 241 candidate chemosensory genes were identified, including 138 odorant receptors (ORs), 24 ionotropic receptors (IRs), 15 gustatory receptors (GRs), 44 odorant-binding proteins (OBPs), 17 chemosensory proteins (CSPs), and three sensory neuron membrane proteins (SNMPs). The results of semi-quantitative reverse transcription PCR (RT-PCR) assays showed that some HhalOBP and HhalCSP genes have tissue-specific and sex-biased expression patterns. Our results provide an insight into the molecular mechanisms of the olfactory system in H. halys and identify potential novel targets for pest control strategies.

In some animals, timing of egg hatching is adjusted in response to cues from clutch mates to synchronize hatching within a clutch and this typically facilitates mass migration of hatchlings from their natal clutch. A recent study in eight species of Pentatomidae revealed that four species show synchronized hatching due to responses to earlier-hatched siblings, by comparing temporal hatching patterns between intact clutches and eggs individually detached from clutches. However, hatchlings of Pentatomidae do not migrate from their natal clutch immediately. In the present study, using the same eight species, we explored the evolutionary reason for the synchronized hatching in Pentatomidae. In all of the species examined except one non-synchronized species, Eurydema rugosum, hatchlings showed egg feeding behavior with greatly different time of onset. The highly synchronized species, Halyomorpha halys and Nezara viridula, had the time of onset of egg feeding earlier than in the other species. In these two species, based on the hatching patterns of eggs individually detached from their clutches, we concluded that eggs can be cannibalized by their earlier-hatched siblings unless they hatch in response to siblings. On the other hand, this was not the case in the moderately synchronized species, Piezodorus hybneri and Plautia stali. In the other three non-synchronized species, Aelia fieberi, Dolycoris baccarum, and Palomena angulosa, eggs seemed not to incur a risk of cannibalism. In intact H. halys clutches, almost no eggs were cannibalized by siblings. In conclusion, synchronized hatching serves as a possible strategy to avoid sibling cannibalism in Pentatomidae, although it can also have some other functions. Eggs should often be able to control when to hatch in response to environmental factors affecting survival of eggs or hatchlings. Species of various taxa show responses to siblings in the same clutch to achieve synchronized hatching among the siblings. It is typically recognized that such synchronized hatching is required so that hatchlings leave their natal clutch together, which serves, for example, to reduce the risk of being preyed on by predators. Here, we present evidence supporting that synchronized hatching observed in some stink bugs helps eggs to avoid being cannibalized by their earlier-hatched siblings. We also show that other stink bugs with no synchronized hatching have no or little risk of sibling egg cannibalism. This study deepens our knowledge that the synchronized hatching can function in various social contexts with siblings.

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an endemic species of East Asia, it was introduced into Europe in 2007. It has a wide range of hosts as it feeds on over 170 host plant species and significantly impacts crop production. In Greece, H. halys causes significant losses in the production of kiwi, peaches, and green beans, thus, control of this species (including biological control) is essential. Here, we focus on the potential impact of native natural enemies of H. halys in Greece. From June to October 2020, we sampled naturally field-laid H. halys egg masses to recover native parasitoids. A total of 20 egg masses of H. halys were collected from infested fields from different locations in northern Greece. Out of 529 eggs, 45 parasitoids managed to hatch successfully. The overall parasitism rate was 8.5%. We found two species of Hymenopteran egg parasitoids attacking H. halys eggs—Anastatus bifasciatus (Geoffrey) (Hymenoptera: Eupelmidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), with the former comprising 58% of all parasitoids that were recovered. These results contribute to the knowledge about the natural enemy community that attacks H. halys in Greece, and the use of these native egg parasitoids in biological control programs may be a viable H. halys management strategy.

Simple Summary Halyomorpha halys (Stål) (Heteroptera: Pentatomidae) is a polyphagous and invasive pest that has been causing severe damage to agricultural systems worldwide including Italy. Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), an egg parasitoid native to regions of Asia where H. halys originated, seems to be one of the most promising solutions for decreasing pest pressure. In 2020, field releases of T. japonicus were approved in Italy with the aim of releasing 120,000 parasitoids. Thus, it was necessary to develop an efficient rearing system to support this biological control program. In this study, some parameters that could influence the rearing of T. japonicus on cold-stored eggs of H. halys were investigated. Refrigeration at 6 °C for as long as several months is an effective method of storage for H. halys egg masses. Female parasitoids produced the highest number of progeny when exposed to egg masses for 72 h. Adult wasps could also be stored at 16 °C for up to 90 days with a negligible decrease in survival, but a significant decrease in production of progeny. Abstract Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), a pest of Asian origin, has been causing severe damage to Italian agriculture. The application of classical biological control by the release of Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), an exotic egg parasitoid, appears to be one promising solution. In Italy, releases of T. japonicus in the field were authorized in 2020. In this study, some parameters that could influence the rearing of T. japonicus in insectaries were investigated. A significantly higher production of progeny was observed on host eggs stored at 6 °C (86.5%) compared to −24 °C (48.8%) for up to two months prior to exposure to parasitism. There were no significant differences in progeny production from single females in a vial provided with only one egg mass (83.2%) or 10 females inside a cage with 6 egg masses (83.9%). The exposure of parasitoids to refrigerated (6 °C) egg masses of H. halys for 72 h led to a significantly higher production of progeny (62.1%) compared to shorter exposures for 48 (44.0%) or 24 h (37.1%). A decline in production of progeny by the same female was detected between the first (62.1%) and the second parasitization (41.3%). Adult parasitoids stored at 16 °C for up to 90 days had an 87.1% survival rate, but a significant decrease in progeny production was detected. These parameters could be adjusted when rearing T. japonicus for specific aims such as the production of individuals for field release or colony maintenance.

Proactive biocontrol could accelerate responses to invasive pests in urban areas — where pesticide use may be unpopular — before they spread to agricultural areas.

A parasitoid wasp, Trissolcus basalis (Wollaston), was recorded parasitizing eggs of the invasive stink bug Halyomorpha halys (Stål) in the United States. This is the first record of this species parasitizing fresh and frozen eggs of H. halys in the United States. First record of Trissolcus basalis parasitizing Halyomorpha halys eggs in the United States.

The brown marmorated stink bug, Halyomorpha halys, is an invasive, phytophagous stink bug of global importance for agriculture. Tissue-specific transcriptomic analysis of the accessory salivary gland, principal salivary gland (PSG) and gut resulted in identification of 234 putative protease and 166 putative nuclease sequences. By mapping the previously reported proteomes of H. halys watery saliva (WS) and sheath saliva to protein sequences translated from the assembled transcripts, 22 proteases and two nucleases in the saliva were identified. Of these, 19 proteases and both nucleases were present in the WS. The majority of proteases and nucleases found in WS were derived from the PSG, in line with ultrastructural observations, which suggest active protein synthesis and secretion by this tissue. The highly transcribed digestive proteases and nucleases of H. halys were similar to those of the southern green stink bug, Nezara viridula, indicating that these pentatomid stink bugs utilize a similar suite of proteases and nucleases for digestion of plant material. The comprehensive data set for the H. halys salivary glands and gut generated by this study provides an additional resource for further understanding of the biology of this pestiferous species.

Halyomorpha halys (Hemiptera: Pentatomidae), native to East Asia, has become a globally invasive pest, as a serious threat to agricultural production and a notorious nuisance pest in urban areas. Considerable efforts have been made so far to develop effective pest control measures to prevent crop damage. Biological control of this invasive stink bug by egg parasitoids has proven to be the most environmentally sustainable long-term solution. Knowledge of the native egg parasitoid fauna is of key importance when implementing a biological control program. Therefore, the main objective of our study was to detect egg parasitoid species associated with H. halys in the Goriška region (Western Slovenia) and to evaluate their impact on the pest population under field conditions. In the years 2019 and 2020, around 4600 H. halys eggs were collected in the wild and more than 3400 sentinel eggs were exposed to detect parasitoids in the field. Five egg-parasitoid species emerged from H. halys eggs: Anastatus bifasciatus (Hymenoptera: Eupelmidae), Telenomus sp., Trissolcus basalis, Trissolcus mitsukurii (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Hymenoptera: Encyrtidae), all of them are new records for Slovenia. The native species, An. bifasciatus, dominated in urban and suburban areas, while non-native Tr. mitsukurii prevailed in agricultural areas. Overall parasitism rates of naturally laid eggs by the parasitoid species complex in 2019 and 2020 was 3.0 and 14.4%, respectively. Rapid recruitment of native parasitoids, early detection of an effective alien parasitoid species and increasing overall parasitism rates are very encouraging results, which need to be followed and verified in future research.

Simple Summary The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), native to Asia, has been accidentally introduced to Europe and North America, where it has become a key pest by feeding on numerous important crops. Although H. halys has not yet established in Australia, there is a general consensus that this is only a matter of time, and thus, it is prudent to investigate management options. Previous studies have modelled the potential distribution of H. halys and one of its principal natural enemies, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae). Here, we developed a similar model of the potential distribution of Trissolcus mitsukurii (Ashmead), which is a primary parasitoid of H. halys in Japan, and which was introduced to Australia in the 1960s to control another introduced pest. We used the three models to examine the overlap in the projected distributions of both T. mitsukurii and T. japonicus with H. halys, and to assess the potential for the two Trissolcus species to help mitigate the impacts of H. halys in its global adventive range. Abstract The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is native to northeast Asia. It was accidentally introduced to Europe and North America, where it has become a key pest, feeding on many important crops. Previous eco-climatic niche modelling indicates that H. halys could expand its distribution vastly, and numerous border interceptions of this pest in many countries, including Australia and New Zealand, indicate that it would be prudent to prepare for its eventual arrival. Similar niche modelling was used to assess the potential distribution of Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), the key parasitoid of H. halys in China. Trissolcus mitsukurii (Ashmead) is one of the main parasitoids of H. halys in Japan. It is known to have existed in Australia since the early 20th century and was also specifically introduced to Australia in the 1960s, and it has now also invaded Italy. We used CLIMEX to model the climatic niche of T. mitsukurii to estimate its global potential distribution. We found that T. mitsukurii should be able to significantly expand its range globally, and that there is a significant degree of overlap in the projected ranges of T. mitsukurii, T. japonicus and H. halys. From a biological control perspective, this implies that the two Trissolcus species may be able to help mitigate the potential impacts of H. halys.

The brown marmorated stink bug, Halyomorpha halys, is a polyphagous pest species of worldwide economic importance. Since the mid-1990s, it has invaded and become established in various countries outside its native Asian range. In the newly invaded areas, biological control by native natural enemies has been shown to be insufficient in the long-term control of this severe pest. Adventive populations of Trissolcus japonicus, an important biological control agent of H. halys in Asia, have been reported from North America and some European countries since the mid-2010s. This egg parasitoid species seems to follow in the wake of the establishment of H. halys populations outside their native Asian range. Here, we report the first discovery of an adventive population of T. japonicus in Germany. In 2020, adult T. japonicus were recovered from parasitized H. halys egg masses (naturally laid and sentinel egg masses) and collected in ruderal areas using an insect suction sampler. The arrival of T. japonicus in Germany, unintentional through pathways yet unknown, corroborates a northbound expansion of its range within Europe. Further field surveys will show the extent of its dispersal and establishment capacities within this new distribution area.

Hidden trophic interactions are important in understanding food web ecology and evaluating the ecological risks and benefits associated with the introduction of exotic natural enemies in classical biological control programs. Although non-target risk is typically evaluated based on evidence of successful parasitism, parasitoid-induced host mortality not resulting in visible evidence of parasitism (i.e., nonreproductive effects) is often overlooked. The adventive establishment of Trissolcus japonicus, an exotic parasitoid of the introduced stink bug Halyomorpha halys, provides an opportunity to investigate the total impact of this parasitoid on target and non-target hosts in the field. We developed a new methodology to measure nonreproductive effects in this system, involving a species-specific diagnostic PCR assay for T. japonicus. We applied this methodology to field-deployed eggs of four pentatomid species, coupled with traditional rearing techniques. Nonreproductive effects were responsible for the mortality of an additional 5.6% of H. halys eggs due to T. japonicus, and were even more substantial in some of the non-target species (5.4&ndash, 43.2%). The observed hidden mortality of native non-target species from an introduced parasitoid could change predictions about direct and indirect ecological interactions and the efficacy of biological control of the target pest.

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is a serious pest in agriculture and forests, as both adults and nymphs feed by piercing the surface of the plant and fruit tissues, causing damage. The eggs of H. halys are commonly attacked by parasitoids, however, the nymph and the adult are rarely attacked by natural enemies. We surveyed the parasitoids of adult H. halys by collecting samples from overwintering populations at three different locations and checked their body surfaces for the presence of tachinid eggs. Any host adults carrying tachinid eggs were reared in a cage for further species identification. We found that the eggs of Pentatomophaga latifascia (Villeneuve) (Diptera: Tachinidae) were laid on the surface of H. halys, and the hatched larvae penetrated the host body and fed internally to develop. The last larval instar emerged from the host to develop into pupae, killing the host in the process. According to the field survey, the average parasitism of H. halys by P. latifascia was 2.42%. The parasitoids of adult H. halys in their native range have so far been little studied and may provide a complementary component of egg parasitoids for biological control against H. halys in invaded areas.

Simple Summary Overwintering populations of the crop pest Halyomorpha halys exhibit cannibalistic behaviour towards conspecifics. Depletion of metabolic reserves and desiccation occurring in winter can be overcome by intraspecific predation. This behaviour may be facilitated by the aggregation of individuals and the suppression of species-specific signals that prevent predation upon conspecifics. Abstract The phytophagous brown marmorated stink bug Halyomorpha halys (Stål) is known to exhibit cannibalistic behaviour towards eggs. Here, we provide evidence of cannibalism among overwintering H. halys adults. Since diapausing individuals have high physiological demands for surviving long periods under stressful conditions, including the risk of depletion of metabolic reserves and desiccation, we assumed that nutritional and water requirements can be met by intraspecific predation. The role of aggregative behaviour in promoting cannibalism is also discussed. Given its evolutionary advantage, this trait should be maintained over generations and may be more widespread than previously considered in species that display aggregative behaviour during adverse seasons.

Building design, maintenance, and management can have significant impacts on accessibility and suitability for pest species. The brown marmorated stink bug, Halyomorpha halys (Stål), causes household nuisance pest problems because of its habit of using human homes as winter refuges. Studies were conducted to understand behaviors and characteristics relevant to this problem, including response to gravity, ability to pass through openings, responses to heat, and mortality estimations in wall assemblies. In the lab, winter shelter seeking bugs were shown to exhibit upward movement, and field observations of bugs on building exteriors gave similar results. In experiments testing the size limits on openings through which bugs could pass, height limited tests excluded most females at 4 mm, and all bugs at 3 mm. Pronotum width limited tests excluded most females at 8 mm and nearly all bugs at 7 mm. Accompanying measurements of over 900 bugs found an average female pronotum width of 8.33 mm and height of 4.03 mm, and male pronotum width of 7.47 mm and height of 3.50 mm, with minimum sizes indicating that only a small percentage of bugs will pass the smallest openings tested. Heat response experiments of shelter seeking bugs were first piloted outdoors, and then modified to be a forced choice indoor test. In outdoor tests on a flat plane wall section with alternating heated sections, bugs did not respond to thermal contrast but rather immediately walked off of the wall. In the indoor forced choice test, a box of four cavity walls was used. Bugs did not respond to the heated sections in either the adjacent or opposite configuration. Thermal simulation modeling was used to evaluate the possible effects of varying wall assembly materials and configurations on cold-related mortality of bugs overwintering in the cavity space behind cladding. Simulation results indicated that bugs electing to overwinter in the space between cladding and sheathing were at risk of freezing deaths, with mortality expectations increasing in better insulated buildings. The results of these studies will inform future control measures and impact studies in buildings. Ph. D.

Background The brown marmorated stink bug (Halyomorpha halys) is an invasive pest in North America which causes severe economic losses on tree fruits, ornamentals, vegetables, and field crops. The H. halys is an extreme generalist and this feeding behaviour may have been a major contributor behind its establishment and successful adaptation in invasive habitats of North America. To develop an understanding into the mechanism of H. halys’ generalist herbivory, here we specifically focused on genes putatively facilitating its adaptation on diverse host plants. Results We generated over 142 million reads via sequencing eight RNA-Seq libraries, each representing an individual H. halys adult. The de novo assembly contained 79,855 high quality transcripts, totalling 39,600,178 bases. Following a comprehensive transcriptome analysis, H. halys had an expanded suite of cytochrome P450 and cathepsin-L genes compared to other insects. Detailed characterization of P450 genes from the CYP6 family, known for herbivore adaptation on host plants, strongly hinted towards H. halys-specific expansions involving gene duplications. In subsequent RT-PCR experiments, both P450 and cathepsin genes exhibited tissue-specific or distinct expression patterns which supported their principal roles of detoxification and/or digestion in a particular tissue. Conclusions Our analysis into P450 and cathepsin genes in H. halys offers new insights into potential mechanisms for understanding generalist herbivory and adaptation success in invasive habitats. Additionally, the large-scale transcriptomic resource developed here provides highly useful data for gene discovery; functional, population and comparative genomics as well as efforts to assemble and annotate the H. halys genome. Electronic supplementary material The online version of this article (10.1186/s12864-017-4281-6) contains supplementary material, which is available to authorized users.

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), the brown marmorated stink bug (BMSB), has become a major pest. Seven experiments examined the nutrient content of their eggs in the context of female reproductive investment and use for experiments. Among 542 clusters examined, an average egg contained 23.50 ± 0.561 µg lipid, 3.17 ± 0.089 µg glycogen, and 3.08 ± 0.056 µg sugar. Mature eggs within a female’s ovary can make up 61% of her total lipid, 35% of glycogen, and 20% of sugar levels. Eggs obtained from a colony reared on a steady diet are expected to have consistent nutrient content. The age of a parental female only slightly affected the lipid level of oviposited eggs but did not affect glycogen or sugar levels. However, egg nutrient content can differ substantially by the source of the parental females; wild eggs had higher lipid but lower sugar content than colony-produced eggs. Further, the length of time that eggs are frozen influenced egg nutrient content. Freshly laid eggs had higher lipid and lower sugar levels than eggs frozen for 1 or 2 yr. Whether an egg turned grey following removal from cold storage did not affect nutrient content, nor did being frozen within 1 or 3 d of oviposition. The temperature at which eggs were left exposed did not impact egg nutrient content, but glycogen decreased and sugar increased with deployment time. This information combined with how factors affect host selection by natural enemies will help refine future experiments that use BMSB egg clusters.

Species of Trissolcus Ashmead are potent natural enemies of stink bugs (Pentatomidae). Research on biological agents to control the brown marmorated stink bug, Halyomorpha halys (Stål) (BMSB), in Western Europe requires reliable taxonomic resources for identification of Trissolcus wasps. To aid this research endeavor, we present a species identification key to females of Palearctic Trissolcus. Morphological characters and concepts of the genus and species groups are discussed. We discovered a number of nomenclatural and identification issues that we here rectify.

Raising public awareness about IAS is essential, but a huge step in citizen assumed responsibility is represented by their willingness to cooperate and help scientist. Recent citizen science initiatives all around the world are leading to amazing results, but Romania has a very low response in citizen-generated data (CGD) on IAS. Mobile agriculture apps started to develop in Romania and to be used by farmers, but not the IAS apps. The current paper analyse the actual situation of Romanian CGD on IAP on different web platforms, presents the results of different attempts of getting information about Halyomorpha halys in Bucharest area from citizen in 2016 and tackle the challenges of CGD on IAP by an online survey addressed to the students and staff of University of Agronomic Science and Veterinary Medicine of Bucharest. Report rates vary from 0.79‰ to 0.38% on web platforms to 0.14% for email and phone, while the answers to the survey related with IAS received 21.2% answers from teachers and colleagues and 10.5% from students. Face-to-face communication seems to improve the participatory rate, but only when personal commitment and passion of the researcher is shown.

The brownmarmorated stink bug, Halyomorpha halys (Stal), is an invasive species from Asia capable of causing severe agricultural damage. It can also be a nuisance pest when it enters and exits anthropogenic overwintering sites. In recent years, pheromone lures and traps for H. halys have been developed and used to monitor populations in field studies. To date, no study has investigated the applicability of these monitoring tools for use indoors by building residents during the overwintering period. Herein, we 1) assessed when in late winter (diapause) and spring (postdiapause) H. halys begins to respond to its pheromone (10,11-epoxy-1-bisabolen-3-ol), 2) evaluated whether pheromone-based tools can be used reliably for monitoring H. halys adults in unheated and heated buildings, and 3) elucidated the potential for indoor management using pheromone-baited traps. A 2-yr trapping study suggested that H. halys began to respond reliably to pheromone-baited traps after a critical photoperiod of 13.5h in the spring. Captures before that point were not correlated with visual counts of bugs in buildings despite robust populations, suggesting currently available pheromone-baited traps were ineffective for surveillance of diapausing H. halys. Finally, because baited traps captured only 8-20% of the adult H. halys known to be present per location, they were not an effective indoor management tool for overwintering H. halys. Our study contributes important knowledge about the capacity of H. halys to perceive its pheromone during overwintering, and the ramifications thereof for building residents with nuisance problems. USDA NIFA SCRI CAP Grant [2016-51181-25409] We would like to thank the excellent technical assistant of McKenzie Allen (USDA-ARS), John Cullum (USDA-ARS), Jean Engelman (Virginia Tech), Elizabeth Fread (Virginia Tech), Torri Hancock (USDA-ARS), Jamie Hogue (Virginia Tech), Adam Morehead (Virginia Tech), Brittany Poling (USDA-ARS), and Steve Schoof (NC State University). This project was funded by a USDA NIFA SCRI CAP Grant 2016-51181-25409. The use of trade names is for the purposes of providing scientific information only, and does not constitute endorsement by the United States Department of Agriculture. The USDA is an equal opportunity employer. Public domain – authored by a U.S. government employee

Egg clutches of many animals hatch synchronously due to parental control [1, 2] or environmental stimulation [3, 4]. In contrast, in some animals, embryos actively synchronize their hatching timing with their siblings to facilitate adaptive behavior in sibling groups, such as mass migration [5, 6]. These embryos require synchronization cues that are detectable from eggs and indicative of when the siblings hatch, such as pre-hatching vocalizations in birds and crocodiles [7, 8]. Previous studies, using methods including artificial presentation of non-specific mechanical stimuli, demonstrated that vibrations or other mechanical forces caused by sibling movements are cues used by some turtles and insects [9, 10, 11, 12, 13]. However, there is no evidence about which movements of tiny embryos or hatchlings, among multiple possibilities, can generate mechanical cues actually detectable through eggs. Here, we show that embryos of the brown marmorated stink bug, Halyomorpha halys, synchronize hatching by responding to single pulsed vibrations generated when siblings crack open their eggshells. An egg-cracking vibration seems to be transmitted to distant eggs within a clutch while still maintaining its function as a cue, thus leading to the highly synchronized hatching pattern previously reported [14]. In this species, it is possible that embryos attempt to hatch with short lags after earlier-hatched siblings to avoid egg cannibalism by them [14]. The present study illustrates the diversity of social-information use by animal embryos for success in the sibling group., カメムシの卵が一斉に孵化する巧妙なメカニズムを発見 --ある卵が割れた振動を合図にきょうだいの卵が孵化する--. 京都大学プレスリリース. 2018-12-28.

The invasive brown marmorated stink bug, Halyomorpha halys (Sta° l) (Hemiptera: Pentatomidae), is an important pest of soybean (Glycine max L. Merr.) in the Mid-Atlantic United States. In order to assess the influence of nonmanaged wooded borders on H. halys infestation patterns in soybean, 12 soybean fields in Orange and Madison Counties, VA, were sampled each week from July to October in 2013 or 2014 for H. halys. At each location, five 2-min visual counts of H. halys life stages were made on tree of heaven (Ailanthus altissima Mill.) and other favorable host trees along a wooded border, on the adjacent soybean edge, 15 m into the soybean field, and 30 m into the field. Seasonal data showed a clear trend at all locations of H. halys densities building up on A. altissima-dominated wooded borders in July, then, gradually moving into adjacent soybean field edges later in the summer. Halyomorpha halys did not move far from the invading field edge, with approximately half as many bugs being present at 15 m into the field and very few being detected 30 m into the field. These results have implications for continued monitoring and management using field border sprays, particularly on edges adjacent to woods. Published version

Brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), has become an important pest of soybean in the Mid-Atlantic US. To assess the influence of tree borders on BMSB infestations in soybean, twelve fields were sampled weekly using five 3-min visual counts of BMSB on tree of heaven (TOH) (Ailanthus altissima) and other host trees along a wooded border, on the adjacent soybean edge, 15 m and 30 m into the soybean field. At all locations, BMSB densities increased on TOH wooded borders in July, then, gradually moved into adjacent soybean borders later in the summer. BMSB did not move far from the field edge, with approximately half as many bugs being present at 15 m into the field and very few being detected 30 m into the field. These results validate the use of border sprays for BMSB control in soybean. Additional studies conducted in 2013 and 2014 compared a visual plant inspection method with a standard sweep net strategy for sampling BMSB. Overall, the two methods were highly correlated with a correlation coefficient of R=0.83. Visual inspection appears to be an effective method for assessing BMSB populations in soybean. One of the major factors affecting the distribution and establishment of invasive species is climate. The CLIMEX modeling software uses climatic and biological factors of species to predict the geographic risk for pest outbreaks. A climate simulation model was run with CLIMEX to determine the potential distribution of BMSB in Virginia based on temperature. To develop a more accurate model, factors like resource availability and source population would need to be considered. Master of Science in Life Sciences