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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]

MIRIDAE, EGGS as food, PREDATORY animals, TEMPERATURE effect, and MEDITERRANEAN flour moth

Three Neotropical predators Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stål) (Hemiptera: Miridae) are considered in Brazil as potential biological control agents of Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) and other tomato pests. This study evaluated the effect of five constant temperatures (16, 20, 24, 28 and 32°C, all ±1°C) on the reproduction, population growth and longevity of these predatory mirids. Adults freshly emerged from nymphs reared at each temperature, were separated in couples and kept in 1.7 l glass pots with tobacco plant seedlings (Nicotiana tabacum L., cv. TNN) as oviposition substrate and ad libitum Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs as food. The shortest pre-oviposition and the longest oviposition periods were observed at 24°C and 28°C in all three mirid species. At 24°C all three species showed the highest daily and total fecundities. The population growth parameters represented by the intrinsic rate of increase (rm) and the finite rate of increase (λ) were highest at 24°C and 28°C, and the net reproductive rate (R0) was highest at 24°C for all three species. Longevities of both males and females were longest at 24°C and 28°C in all three mirids. The size of tibia and adult weight in the three species were greatest at 20°C and 28°C, respectively. Differences in values for all above variables were small and often statistically non-significant for the three mirid species at the same temperature. Also, not a single significant difference was found for any of the growth parameters at each of the temperatures, including rm. The results indicate that temperatures in the range from 24-28°C are best for reproduction and population growth of C. infumatus, E. varians and M. basicornis. The factitious prey E. kuehniella is an excellent food source and tobacco plants provide a good rearing substrate for these mirids. The obtained results may assist in developing a mass rearing method for C. infumatus, E. varians and M. basicornis, in determining optimal timing and frequency of mirid releases in the crop, and in determining whether they are active at the temperature spectrum observed during tomato production in the field or greenhouse. [ABSTRACT FROM AUTHOR]

PLANT chemical defenses, VIGNA, and COREIDAE

The effects of secondary metabolites in different Vigna species on the development of Clavigralla tomentosicollis were investigated in an artificial seed system using different fractions of crude pod extracts, while the orientation response of this pod-bug to volatile extracts was studied using a dual-choice olfactometer. Feeding on the neutral fraction extracts, in contrast to the basic and acidic fractions, resulted in significantly higher mortalities, longer total developmental time, and lower growth index of the insects in comparison with controls. All volatile extracts elicited an avoidance reaction by C. tomentosicollis, except the volatile from the susceptible genotype IT84S-2246 which generally attracted as many insects as controls. Extracts from wild Vigna species showed higher activity than those from their cultivated relatives. The present study which has established that most secondary metabolites in cowpea pods were localized in the neutral fraction of the crude extract, could facilitate experiments on the separation and characterization of the toxic factors involved. [ABSTRACT FROM AUTHOR]

BIODIVERSITY, VERTEBRATES, HABITATS, GLACIATION, and PLIOCENE Epoch

It is now rare to find a semi-aquatic organism group with which to vigorously test whether their diversification model and distribution pattern are closely related to the Cenozoic temperature variation. This hypothesis is explored for water striders of the genera Aquarius Schellenberg, Gerris Fabricius and Limnoporus Stål, which comprise a monophyletic clade with primarily Holarctic distribution. We sample almost 90% of the currently recognized Aquarius, Gerris and Limnoporus species. Five DNA fragments from 62 species are used to reconstruct a phylogram. Divergence time is estimated using Bayesian relaxed-clock method and three fossil calibrations. We investigate diversification dynamics, biogeography and ancestral state reconstruction by using maximum-likelihood, Bayesian and parsimony approaches. Our results showed that the crown of the three genera originated and underwent an initial diversification in Asia at 72 Ma (HPD: 59-86 Ma) in the Late Cretaceous, subsequently expanding into other regions via dispersal. The Bering Land Bridge was the major migration route between Eurasia and North America but was interrupted before the early Oligocene (34 Ma). Ancestors most likely used lentic habitats, and a minimum of two independent shifts to lotic habitats occurred in the initial diversification. Cenozoic temperature variation regulated the evolutionary history of Holarctic water striders of the genera Aquarius, Gerris and Limnoporus. Temperature warming during Stage I (52-66 Ma) was associated with the disappearance of shallow lentic habitats; this phenomenon forced certain lentic lineages to colonize new lotic habitats and promoted the diversification of lineages. Temperature cooling during Stage II (after 34 Ma) was associated with the fragmentation of water habitats of the 'mixed-mesophytic' belt, resulting in the extinction of historical taxa and influencing close lineages that shaped the present disjunct Eurasian-North American distribution. [ABSTRACT FROM AUTHOR]

ESSENTIAL oils, REPELLENTS, STINKBUGS, HEMIPTERA, LEMONGRASS oil, SPEARMINT oil, and METHYL benzoate

The brown marmorated stink bug ( BMSB), Halyomorpha halys ( Stål), native to Northeastern Asia, is a serious invasive pest in the United States, Canada, Switzerland, Germany and France. Several common essential oils and their compositions were tested against BMSBs as potential repellents. All the tested individual essential oils and a ternary oil blend showed significant repellency to both BMSB nymphs and adults. Clove oil, lemongrass oil, spearmint oil, ylang-ylang oil, and the ternary oil mixture (clove, lemongrass and spearmint) almost completely blocked attraction of BMSBs to the stink bug attractant-baited traps; whereas wintergreen oil, geranium oil, pennyroyal oil and rosemary oil resulted in 60-85% trap catch reductions. Over 20 BMSB antennally active compounds were identified from SPME headspace samples of the eight repellent essential oils using GC- EAD and GC- MS techniques. Among the synthetic EAD-active compounds tested in the field, eugenol, l-carvone, p/l-menthone, pulegone, methyl salicylate, trans/ cis-citral, methyl benzoate and β-caryophyllene significantly reduced trap catches of BMSBs by 72-99%; these compounds are likely responsible for the repellency of their corresponding essential oils. Surprisingly, a synthetic mixture of the predacious spined soldier bug ( SSB) [ Podisus maculiventris (Say)] aggregation pheromone ( trans-2-hexenal, α-terpineol and benzyl alcohol) also showed a significant inhibition of BMSB response to its attractants. These repellent essential oils and their active compounds, as well as the synthetic SSB pheromone, are potentially useful as part of an efficient, environmentally sound semiochemical-based IPM programme to combat this serious invasive stink bug. [ABSTRACT FROM AUTHOR]

RHODNIUS, CONENOSES, CLASSIFICATION of insects, and SPECIES diversity

Tribe Rhodniini includes Rhodnius Stål and Psammolestes Bergroth. Enzymatic and molecular evidence suggest the tribe is monophyletic. Most species are wild, living in palms and bird nests. Traditionally both genera were considered related; nevertheless, molecular studies don't support the Rhodnius monophyly. The goal was to phylogenetically analyze morphometric variation in wing architecture in support of Rhodniini taxonomy and systematics. We photographed 524 wings of five representatives of Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål (n = 16), and R. neivai Lent (n = 22). As outgroups we studied four representatives of Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183), and Triatoma maculata (Erichson) (n = 109). Landmark coordinate (x, y) configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Then, wing shape variables (confidence intervals from relative warps) and centroid size were cladistically analysed. Statistical analyses of variance found not significant differences in wing isometric size (Kruskal-Wallis) among P. arthuri-R. neivai-R. pictipes; R. robustus-R. prolixus-T. maculata and between P. rufotuberculatus-P. geniculatus. The a posteriori re-classification was perfect in E. mucrunatus 100% and R. pictipes, followed by T. maculata 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, and R. robustus 76%. Cladistic analyses under parsimony selected two most parsimonious trees (L=4.461 IC=0.973 and IR=0.979), where the strict consensus showed a monophyletic group with Panstrongylus (rufotuberculatus + geniculatus) and Triatoma + Rhodniini (Rhodinus + Psammolestes), but internally it shows the paraphyly of Rhodnius regarding Psammolestes. The congruence between these results and previous molecular analyses in Rhodniini, reveal the phylogenetic information of our morphometric characters as support to systematic studies, allowing the combination of geometric morphometrics and phylogenetic methods for the first time in this group. [ABSTRACT FROM AUTHOR]

BIOLOGICAL weed control, BIOLOGICAL pest control agents, CHRYSOMELIDAE, BEETLES, HYMENOPTERA, and EUCALYPTUS

The solitary larval endoparasitoid Eadya daenerys Ridenbaugh (Hymenoptera: Braconidae) is a proposed biocontrol agent of Paropsis charybdis Stål (Coleoptera: Chrysomelidae, Chrysomelinae), a pest of eucalypts in New Zealand. Eadya daenerys oviposition behaviour was examined in two assay types during host range testing, with the aim of improving ecological host range prediction. No‐choice sequential and two‐choice behavioural observations were undertaken against nine closely related species of New Zealand non‐target beetle larvae, including a native beetle, introduced weed biocontrol agents, and invasive paropsine beetles. No behavioural measure was significantly different between no‐choice and two‐choice tests. In sequential no‐choice assays the order of first presentation (target–non‐target) had no significant effect on the median number of attacks or the attack rate while on the plant. Beetle species was the most important factor. Parasitoids expressed significantly lower on‐plant attack rates against non‐targets compared to target P. charybdis larvae. The median number of attacks was always higher towards target larvae than towards non‐target larvae, except for the phylogenetically closest related non‐target Trachymela sloanei (Blackburn) (Coleoptera: Chrysomelidae, Chrysomelinae). Most non‐target larvae were disregarded upon contact, which suggests that the infrequent attack behaviour observed by two individual E. daenerys against Allocharis nr. tarsalis larvae in two‐choice tests and the frass of Chrysolina abchasica (Weise) was probably abnormal host selection behaviour. Results indicate that E. daenerys is unlikely to attack non‐target species apart from Eucalyptus‐feeding invasive paropsines (Chrysomelinae). Non‐lethal negative impacts upon less preferred non‐target larvae are possible if E. daenerys does attack them in the field; however, this is likely to be rare. [ABSTRACT FROM AUTHOR]