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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]

MELIACEAE, HOST plants, HEMIPTERA, STINKBUGS, and INSECT antifeedants

Currently, the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is considered an agricultural and nuisance pest in Georgia. The invasive chinaberry tree, Melia azedarach L. (Meliaceae), commonly grows in dense thickets along roadsides, and in woodlands adjacent to agricultural crops across the southeastern USA. Thus, the objective of this study was to determine the potential of M. azedarach to serve as a host plant of H. halys by examining mortality and feeding of first and second instars on M. azedarach leaves vs. carrot (i.e., a control diet), and documenting presence of H. halys on M. azedarach in woodlands at 2 locations in Georgia where this stink bug has become established. Over all sampling dates and locations, the number of H. halys in chinaberry was very low (0.1 per tree), and only 3 late instars and 1 adult were observed feeding on M. azedarach at 1 field site late in the season. Percentage feeding by second instars of H. halys was lower for individuals given M. azedarach leaves vs. those provided with carrot, most likely indicating that compounds in M. azedarach have an antifeeding effect. In fact, mortality for second instars on M. azedarach leaves was very high, and thus we conclude that M. azedarach is an unsuitable host plant for H. halys. [ABSTRACT FROM AUTHOR]

STIMULANTS, LEAFHOPPERS, RICE diseases & pests, BIOLOGICAL assay, and METHANOL

A crude rice extract caused a higher probing response than did the control in the green rice leafhopper, Nephotettix nigropictus. Bioassay-guided separation led to the isolation of four active compounds, isoscoparin 2"-O-glucoside, isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside, isoscoparin 2"-O-(6"'-(E)-p-coumaroyl)glucoside, and isovitexin 2"-O-(6"'- (E)-feruloyl)glucoside from ODS 40% methanol in water faction. Each of the compounds, or any combination without one of the four compounds, caused weaker probing responses than the crude rice extract. The activity was recovered only when all the compounds were combined. [ABSTRACT FROM AUTHOR]

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]

The work's aims were to identify both harmful and helpful insect species for safflower crop and to study their distribution along time in relation to plant phenological state. The insect species identified as harmful were: Uroleucon jaceae L., Capitophorus elaeagni, Frankliniella occidentalis P., Dichelops furcatus (F.), Athaumasthus haematicus (Stál), Nezara viridula (L.), Nysius simulans Stál, Edessa meditabunda (F.), Piezodorus guildinii (W.), Helicoverpa zea B., Epicauta adspersa K., Spodoptera frugiperda (J. E. Smith), Chauliognathus scriptus (Germ.), Pantomorus auripes H. and Rachiplusia nu (G.). Regarding aphids, their highest density was observed at the beginning of November, when crop was in the state of branching, with invasion mainly of the upper third of plants: leaves, young shoots and flower heads. Among all harmful true bugs found in the crop, red bug - Athaumastus haematicus (Stál)- comprised the highest proportion and was detected before aphids attacks, when stem elongation of plants was just beginning. As for beneficial species, the six insects detected in sufflower crop were Hippodamia convergens G., Eriopis connexa G., Harmonia axyridis (P.), Nabis sp., Ophion sp. and Apis melifera L., besides various spider species. The coccinellids- Hippodamia convergens; Eriopis connexa and Harmonia axydiris performed as the main natural control agents at crop. KE [ABSTRACT FROM AUTHOR]