BROWN marmorated stink bug, PREDATION, HEMIPTERA, STINKBUGS, PARASITISM, and LAURACEAE
The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a polyphagous pest that disperses from non-crop host plants into crops in search of food. Sassafras trees (Sassafras albidum (Nutt.) Nees; Lauraceae) are found commonly in woodland habitats in the southeastern US and may therefore be a potential host. The main objective of this 2-yr study was to determine if sassafras serves as a host plant for this pest in woodland habitats adjacent to crops in Prattville, Alabama, and Byron, Georgia, USA. Each yr pheromone-baited traps were deployed in the canopy of sassafras trees to capture H. halys. We also evaluated parasitism and predation of H. halys sentinel egg masses by native parasitoids and predators in sassafras. Halyomorpha halys adult males and females as well as second through fifth instars were captured in traps and observed in sassafras trees over the season at both locations each yr of the study. Trissolcus euschisti Ashmead (Hymenoptera: Scelionidae) (67.7%) and Anastatus reduvii (Howard) (Hymenoptera: Eupelmidae) (18.3%) were the primary parasitoid species that emerged from H. halys sentinel egg masses. Stylet sucking (62.3%) and chewing (32.0%) were the primary types of predation on H. halys eggs. We conclude that sassafras is a reproductive host plant for H. halys, and native natural enemies prey on and parasitize H. halys egg masses in this host plant. La chinche hedionda invasora marrón marmolada, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), es una plaga polífaga que se dispersa de plantas hospedantes no cultivadas a los cultivos en busca de alimento. Se les encuentran en los árboles de sasafrás (Sassafras albidum [Nutt.] Nees; Lauraceae) comúnmente en hábitats boscosos del sureste de los EE. UU. y por lo tanto este puede ser un hospedero potencial. El objetivo principal de este estudio de 2 años fue determinar si el sasafrás sirve como planta hospedera para esta plaga en hábitats boscosos adyacentes a cultivos en Prattville, Alabama, y Byron, Georgia, EE. UU. Cada año, se colocaron trampas cebadas con feromonas en el dosel de los árboles de sasafrás para capturar H. halys. También evaluamos el parasitismo y la depredación de masas de huevos centinela de H. halys por parasitoides nativos y depredadores en sasafrás. Se capturaron machos y hembras adultos así como ninfas del segundo al quinto estadio de Halyomorpha halys en las trampas, y se observaron en árboles de sasafrás durante la temporada en ambos lugares cada año del estudio. Trissolcus euschisti Ashmead (Hymenoptera: Scelionidae) (67,7%) y Anastatus reduvii (Howard) (Hymenoptera: Eupelmidae) (18,3%) fueron las principales especies de parasitoides que emergieron de las masas de huevos centinela de H. halys. La succión por los estiletes (62,3%) y la masticación (32,0%) fueron las principales clases de depredación sobre los huevos de H. halys. Concluimos que el sasafrás es una planta hospedera reproductiva para H. halys, y los enemigos naturales nativos se alimentan y parasitan las masas de huevos de H. halys en esta planta hospedera. [ABSTRACT FROM AUTHOR]
BROWN marmorated stink bug, STINKBUGS, PARASITISM, PREDATION, and HEMIPTERA
Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative. [ABSTRACT FROM AUTHOR]
STINKBUGS, BROWN marmorated stink bug, HYMENOPTERA, OVIPARITY, BIOLOGICAL pest control agents, GREENBUG, and HOSTS of parasitoids
• We tested the physiological host ranges of an introduced biocontrol agent (T. basalis) and native parasitoid (T. oenone). • T. basalis attacks and develops in all nine pentatomid taxa we tested. • The native T. oenone attacks and develops in seven out of eight pentatomid species we tested. • Parasitism efficiencies were high for all treatments (>60%). Retrospective host range testing is essential for understanding the physiological host range of introduced biological control agents (BCAs) and updating forecasts of non-target risks. It is especially important to conduct this work if there was no host range testing prior to release of the agent. Trissolcus basalis Wollaston was released in New Zealand in 1949 against green vegetable bug (Nezara viridula [L.]), but host range testing was never undertaken, and subsequent work in the 1960s was only of a qualitative nature and remains incomplete. The host-parasitoid complex between New Zealand pentatomids, T. basalis , and the native pentatomid parasitoid Trissolcus oenone Dodd, is therefore poorly understood. We conducted no-choice oviposition tests between the two resident Trissolcus species and all available New Zealand pentatomid species to characterise the physiological (=fundamental) host ranges of these parasitoids. We present the results of the first retrospective host-specificity study on T. basalis in New Zealand. Our results show T. basalis attacks and develops in all nine pentatomid taxa we exposed it to (including the endemic alpine species Hypsithocus hudsonae Bergroth), while T. oenone attacks and develops in seven out of eight pentatomid species we tested it against (and its capacity to attack H. hudsonae remains unknown). Parasitism efficiencies for all treatments exceeded 60%, while development times were similar for both parasitoids regardless of host. We discuss the importance of physiological host range testing for understanding potential non-target effects. Trissolcus japonicus Ashmead (Hymenoptera: Scelionidae) was recently approved for release in New Zealand against brown marmorated stink bug Halyomorpha halys Stål (Hemiptera: Pentatomidae), subject to its potential establishment, and we examine our results in the context of potential competition between introduced parasitoids for non-target species. [ABSTRACT FROM AUTHOR]
Kawagoe, James C, Abrams, Adelaine E, Lourie, Austin P, and Walse, Spencer S
Pest Management Science; Jul2022, Vol. 78 Issue 7, p3090-3097, 8p
STINKBUGS, BROWN marmorated stink bug, CARBON dioxide, FUMIGATION, ATMOSPHERIC carbon dioxide, HEMIPTERA, and DILUTION
BACKGROUND: The brown marmorated stink bug (BMSB), Halyomorpha halys, has caused significant agricultural damage to numerous hosts, so agricultural producers seek to limit its spread. Where established, BMSB can also cause substantial urban and commercial disturbance, as overwintering adults may seek refuge inside dwellings, covered spaces, vehicles, and consignments. Phytosanitary authorities are most concerned with the importation of 'hitchhiking' adults in this refugia, with certain countries requiring a quarantine treatment to mitigate risk. This study explores fumigation with ethyl formate, applied as 16.7% by mass dilution in carbon dioxide, for control of adult BMSB. RESULTS: The induction of diapause, to simulate overwintering physiology, resulted in 2‐ and 3‐fold increases in the tolerance of adults toward this ethyl formate fumigation at 10 ± 0.5 °C (x¯±2s) lasting for 8 and 12 h, respectively. However, a decreased tolerance (0.7‐fold) of diapausing specimens was observed for a 4‐h duration. Diapausing and nondiapausing adult BMSB can be controlled at the probit 9 level if the headspace concentration of ethyl formate, [EF], in the carbon dioxide mixture is maintained ≥7.68 mg L−1 for 12 h at 10 ± 0.5 °C (x¯±2s). If the duration is shortened to 4 h, [EF] must be maintained ≥14.73 mg L−1 over the course of fumigation. CONCLUSION: The toxicity of ethyl formate in this mixture can be distinct for different physiological states of the same life stage, as evidenced by a ca. 3‐fold increase in the Haber's z parameter for adult BMSB when in diapause. Respective to the physiological state of adults, this study identifies how the applied dose and/or treatment duration can be modulated (i.e. tuned) to ensure adequate toxicological efficacy toward BMSB infesting hosts or refuge at temperatures ca. >10 °C. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]
Leers, Math P. G., Deneer, Ruben, Mostard, Guy J. M., Mostard, Remy L. M., Boer, Arjen-Kars, Scharnhorst, Volkher, Stals, Frans, Kleinveld, Henne A., and van Dam, Dirk W.
PLoS ONE. 6/28/2022, Vol. 17 Issue 6, p1-12. 12p.
MEDICAL personnel, BLOOD testing, COVID-19 testing, SICK leave, and HOSPITALS
Background: COVID-19 is an ongoing pandemic leading to exhaustion of the hospital care system. Our health care system has to deal with a high level of sick leave of health care workers (HCWs) with COVID-19 related complaints, in whom an infection with SARS-CoV-2 has to be ruled out before they can return back to work. The aim of the present study is to investigate if the recently described CoLab-algorithm can be used to exclude COVID-19 in a screening setting of HCWs. Methods: In the period from January 2021 till March 2021, HCWs with COVID-19-related complaints were prospectively collected and included in this study. Next to the routinely performed SARS-CoV-2 RT-PCR, using a set of naso- and oropharyngeal swab samples, two blood tubes (one EDTA- and one heparin-tube) were drawn for analysing the 10 laboratory parameters required for running the CoLab-algorithm. Results: In total, 726 HCWs with a complete CoLab-laboratory panel were included in this study. In this group, 684 HCWs were tested SARS-CoV-2 RT-PCR negative and 42 cases RT-PCR positive. ROC curve analysis showed an area under the curve (AUC) of 0.853 (95% CI: 0.801–0.904). At a safe cut-off value for excluding COVID-19 of -6.525, the sensitivity was 100% with a specificity of 34% (95% CI: 21 to 49%). No SARS-CoV-2 RT-PCR cases were missed with this cut-off and COVID-19 could be safely ruled out in more than one third of HCWs. Conclusion: The CoLab-score is an easy and reliable algorithm that can be used for screening HCWs with COVID-19 related complaints. A major advantage of this approach is that the results of the score are available within 1 hour after collecting the samples. This results in a faster return to labour process of a large part of the COVID-19 negative HCWs (34%), next to a reduction in RT-PCR tests (reagents and labour costs) that can be saved. [ABSTRACT FROM AUTHOR]