scholarly journals Trissolcus japonicus (Hymenoptera: Scelionidae) Causes Low Levels of Parasitism in Three North American Pentatomids Under Field Conditions

2019 ◽  
Vol 19 (4) ◽  
Author(s):  
Joshua M Milnes ◽  
Elizabeth H Beers

Abstract Trissolcus japonicus (Ashmead), an Asian parasitoid of Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), was first detected in North America in 2014. Although testing in quarantine facilities as a candidate for classical biological control is ongoing, adventive populations have appeared in multiple sites in the United States, Canada, and Europe. Extensive laboratory testing of T. japonicus against other North American pentatomids and H. halys has revealed a higher rate of parasitism of H. halys, but not complete host specificity. However, laboratory tests are necessarily artificial, in which many host finding and acceptance cues may be circumvented. We offered sentinel egg masses of three native pentatomid (Hemiptera: Pentatomidae) pest species (Chinavia hilaris (Say), Euschistus conspersus Uhler, and Chlorochroa ligata (Say)) in a field paired-host assay in an area with a well-established adventive population of T. japonicus near Vancouver, WA. Overall, 67% of the H. halys egg masses were parasitized by T. japonicus during the 2-yr study. Despite the ‘worst case’ scenario for a field test (close proximity of the paired egg masses), the rate of parasitism (% eggs producing adult wasps) on all three native species was significantly less (0.4–8%) than that on H. halys eggs (77%). The levels of successful parasitism of T. japonicus of the three species are C. hilaris > E. conspersus > C. ligata. The potential impact of T. japonicus on these pentatomids is probably minimal.

2021 ◽  
Author(s):  
Dalton C Ludwick ◽  
Layne B Leake ◽  
William R Morrison ◽  
Jesús R Lara ◽  
Mark S Hoddle ◽  
...  

Abstract Halyomorpha halys (Stål) is an invasive pest in the United States and other countries. In its native range, H. halys eggs are parasitized by a co-evolved parasitoid, Trissolcus japonicus (Ashmead). In the United States, T. japonicus, a classical biological control candidate, is being redistributed in many states where adventive populations exist. To establish if H. halys egg holding conditions affect T. japonicus foraging behavior or successful parasitism, naïve, female parasitoids from an adventive population were allowed to forage in laboratory bioassay arenas with either fresh or frozen (−20 or −80°C) egg masses, the latter held for five durations ranging from 1 h to 112 d. Parasitoid movements were recorded for 1 h. Thereafter, parasitoids were transferred with the same egg mass for 23 h. Additionally, female parasitoids from a quarantine colony were exposed to: 1) pairs of fresh egg masses and egg masses frozen at −40°C (>24 h) or 2) a single fresh egg mass or egg mass frozen at −40°C (<1 h). All exposed egg masses were held to assess progeny emergence. In the foraging bioassay, holding temperature and storage duration appeared to influence host-finding and host quality. Egg masses held at −80°C and fresh egg masses resulted in significantly greater levels of parasitism and progeny emergence compared with eggs held at −20°C. No differences were recorded between egg masses held at −40°C for ≤1 h and fresh egg masses. These results will help refine methods for preparation of egg masses for sentinel monitoring and parasitoid mass rearing protocols.


Author(s):  
Christopher S. Bajwa ◽  
Earl P. Easton ◽  
Harold Adkins ◽  
Judith Cuta ◽  
Nicholas Klymyshyn ◽  
...  

In 2007, a severe transportation accident occurred near Oakland, California, at the interchange known as the “MacArthur Maze.” The accident involved a double tanker truck of gasoline overturning and bursting into flames. The subsequent fire reduced the strength of the supporting steel structure of an overhead interstate roadway causing the collapse of portions of that overpass onto the lower roadway in less than 20 minutes. The US Nuclear Regulatory Commission has analyzed what might have happened had a spent nuclear fuel transportation package been involved in this accident, to determine if there are any potential regulatory implications of this accident to the safe transport of spent nuclear fuel in the United States. This paper provides a summary of this effort, presents preliminary results and conclusions, and discusses future work related to the NRC’s analysis of the consequences of this type of severe accident.


Insects ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 840
Author(s):  
Barbara Bittau ◽  
Maria Luisa Dindo ◽  
Giovanni Burgio ◽  
Giuseppino Sabbatini-Peverieri ◽  
Kim Alan Hoelmer ◽  
...  

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.


Insects ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 833
Author(s):  
Dalton C. Ludwick ◽  
Jessica Patterson ◽  
Layne B. Leake ◽  
Lee Carper ◽  
Tracy C. Leskey

Halyomorpha halys (Stål, 1855) (Hemiptera: Pentatomidae) is an invasive species in the United States, where it has caused significant damage to specialty crops, including apples. While integrated pest management techniques have been developed for H. halys in apple, including spray application techniques, it is unknown how these techniques affect foraging, adventive Trissolcus japonicus (Ashmead, 1904) (Hymenoptera: Scelionidae), and its offspring. In this study, egg masses (unparasitized and 2 and 7 day parasitized pre-treatment) were placed in apple orchards in treated and untreated locations that received full block insecticide applications or reduced application techniques, including border row or alternate row middle applications. Bifenthrin, thiamethoxam + λ-cyhalothrin, clothianidin, and methomyl were evaluated. Egg masses were retrieved 24 h after spray applications. For 2 and 7 day parasitized pre-treatment, adult T. japonicus emergence was recorded from each egg mass. For unparasitized egg masses, T. japonicus females were given 24 h to forage and oviposit on post-treatment egg masses with female survivorship, and adult emergence from egg masses was recorded. Female survivorship was significantly lower on post-treatment egg masses retrieved from areas receiving bifenthrin applications. Emergence from post-treatment egg masses was affected by thiamethoxam + λ-cyhalothrin, bifenthrin, and methomyl in some treated areas, whereas less impact was observed on 2 and 7 day pre-treatment parasitized egg masses in general. These data provide further insights into H. halys management and the potential impact of T. japonicus in sprayed orchard agroecosystems.


2020 ◽  
Vol 12 (2) ◽  
pp. 71-111
Author(s):  
Z. W. Iwanowski ◽  
D. M. Rozental

The paper examines a complex web of domestic and external issues which have both provoked a systemic crisis in Venezuela and, at the same time, determined its specificity in comparison with the wave of protests sweeping across Latin America in 2019.The authors conclude that the escalation of the conflict in Venezuela was caused not only by the standoff between the legislative and the executive branches of the government, but also by the split of the whole society into proponents and opponents of ‘socialism of the 21st century’. The contradictions have led to the formation of the parallel branches of power: two presidents, two parliaments and two supreme courts (one of them in exile) which de facto coexist in the country and each claims exclusive rights and legitimacy.The authors also stress that the situation in Venezuela has obvious regional consequences. The miscalculations of the incumbent president were used in election campaigns in other Latin American countries and became one of the reasons for the defeat of left candidates, the subsequent ‘right drift’ leading to the isolation of the republic. The new political landscape has also affected the architecture of integration associations, which failed to develop a unified position toward the Bolivarian regime.Furthermore, in a current heightened state of international tensions Venezuela has turned into a theatre of international rivalry and conflict involving all the key subjects of world politics. The United States, China, Russia and the European Union compete for the energy resources of the country and pursue their own strategic interests. The inability or unwillingness of external forces to reach compromise and to bring the parties to the negotiating table can pose a threat to peace and international security.As a result, Venezuela has become one of the most turbulent countries in the region. At the same time, the repeated outbursts of protest waves are significantly different from popular uprisings in other Latin American states. In the worst-case scenario, a constantly worsening situation may result in a social explosion which threatens to make the Bolivarian Republic another hot spot of the planet.


2016 ◽  
Vol 23 ◽  
pp. 20
Author(s):  
Odia Bintou Cissé

On June 27, 2013, the Senate passed the Border Security, Economic Opportunity, and Immigration Modernization Act of 2013 (referred to as S.744). The bill addresses key elements of the immigration process through five sections. This analysis serves as an ex-ante Cost-Benefit Analysis (CBA) of the proposed Registered Provisional Immigrant (RPI) program under Section II of S.744, which would allow undocumented immigrants in the US to obtain legal status. The CBA looks at a 10-year timeframe from 2015 through 2025 and estimates the costs and benefits to four groups: undocumented immigrants, US taxpayers, employers of undocumented immigrants, and the United States Citizenship and Immigration Services (USCIS) under a base case scenario, a distributional weight scenario, and a worst-case scenario. Given the positive net benefits observed under the three scenarios, significant evidence recommends the implementation of the RPI program.


2019 ◽  
Vol 112 (4) ◽  
pp. 1997-2000 ◽  
Author(s):  
N F Quinn ◽  
E J Talamas ◽  
T C Leskey ◽  
J C Bergh

Abstract Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an invasive pest that has established in much of the United States. Adventive populations of an effective Asian egg parasitoid of H. halys, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), have been detected in several states, including Virginia, and its geographic range is expanding. Documenting changes in its distribution and abundance have thus become key research priorities. For these specific purposes, surveillance of T. japonicus over large geographic areas using sentinel H. halys egg masses may not be optimally efficient, and examination of alternative sampling tactics is warranted. In 2016, sentinel H. halys egg masses were deployed as vertical transects in the canopy of female Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae) in Virginia. A brief follow-up study in 2016 using yellow sticky traps deployed in the same trees yielded captures of T. japonicus, leading to a comparison of vertical transects of sentinel eggs and yellow sticky traps in 2017. Both methods yielded T. japonicus detections only in the middle and upper tree canopies, whereas other known H. halys parasitoids were detected in the lower, middle, or upper canopies. Based on this information, a method for deploying yellow sticky traps in the middle canopy of H. halys host trees was assessed in 2017, yielding T. japonicus captures. A comparison of estimated time inputs revealed that traps were more efficient than sentinel eggs in this regard. Results are discussed in relation to the utility of each sampling method to address specific questions about the range expansion and ecology of T. japonicus.


2019 ◽  
Vol 151 (6) ◽  
pp. 824-826 ◽  
Author(s):  
Tara D. Gariepy ◽  
Elijah J. Talamas

AbstractWe report the detection and adventive establishment of the samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), a candidate classical biological control agent for the invasive Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), in southwestern Ontario, Canada. Nine naturally laid, field-collected pentatomid egg masses were collected in 2017 and 2018, and two of these egg masses, belonging to Halyomorpha halys and Podisus maculiventris (Say) (Hemiptera: Pentatomidae), produced adults of T. japonicus. The identification of T. japonicus was confirmed using DNA barcoding as well as morphological characteristics. The remaining egg masses yielded adults of the native Telenomus podisi Ashmead (Hymenoptera: Platygastridae) and Anastatus reduvii (Ashmead) (Hymenoptera: Eupelmidae).


Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 258
Author(s):  
Hillary M. Peterson ◽  
Elijah Talamas ◽  
Grzegorz Krawczyk

The samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), is an egg parasitoid associated with the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae). Trissolcus japonicus is a candidate for classical biological control of H. halys populations. Since 2014, adventive populations of T. japonicus have been detected in 14 US states, in the Canadian provinces of British Columbia and Ontario, and in two European countries, Switzerland and Italy. Establishing baseline information about populations of T. japonicus is important, as this species is not host specific to H. halys and the potential ecological effects of the accidental introductions are not fully known. In this study, yellow sticky cards were deployed at commercial fruit orchards in nine counties in Pennsylvania separated by more than 400 km. Trissolcus japonicus was detected on cards in eight counties, and in two habitats, in the orchard and at the forest border. Other native species of Scelionidae known to attack the eggs of H. halys were also identified, including Trissolcus euschisti (Ashmead), Trissolcus brochymenae (Ashmead), and Telenomus podisi Ashmead (Hymenoptera: Scelionidae). These results are important baseline ecological knowledge for both T. japonicus, which appears to be established in orchards throughout Pennsylvania, and other native Scelionidae.


Sign in / Sign up

Export Citation Format

Share Document