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1.
Clin Exp Allergy ; 52(4): 489-498, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34822191

RESUMO

The yellow-legged or Asian wasp (Vespa velutina nigrithorax) has spread rapidly across Europe since its first introduction in France, in 2004. Originally from South-East Asia, it is considered an invasive species outside its native region. Apart from the ecological and economic implications of its presence, it may cause health problems to humans due to the toxic and allergenic components of its venom. Vespa velutina nigrithorax has become the most prevalent cause of anaphylaxis due to Hymenoptera venom in some regions of Spain. Although sIgE against both antigen 5 (Vesp v 5) and A1-phospholipase (Vesp v 1) has been detected in these patients, only Vesp v 5 may be considered a dominant allergen. Interestingly, Vesp v 1 appears to be a glycosylated allergen different from A1-phospholipases from other species. Inhibition studies suggest that Vespula spp venom could behave as primary sensitizer. Besides, changes in sIgE and sIgG4 during Vespula venom immunotherapy in patients with anaphylaxis due to V. velutina support the use of Vespula venom extracts to treat these patients. The purpose of this review is to explore the biological behaviour of V. velutina and to summarize the current knowledge of the allergic reactions provoked by this wasp.


Assuntos
Anafilaxia , Venenos de Artrópodes , Vespas , Anafilaxia/terapia , Animais , Dessensibilização Imunológica , Humanos , Venenos de Vespas , Vespas/fisiologia
2.
Sci Rep ; 12(1): 7449, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523992

RESUMO

Adult wasps primary food resource is larval saliva. This liquid secretion consists mainly of amino acids and carbohydrates processed from the prey brought to the colony by the foragers. However, adults also regularly consume floral nectar. The nectar's most abundant proteinogenic amino acid is proline, and the two most abundant non-proteinogenic amino acids are ß-alanine and GABA. These three amino acids are also common in larval saliva. Here, we study the effect of these dietary amino acids on the physiology and nest construction behavior of the Oriental hornet. Our results reveal their deleterious effects, especially at high concentrations: ß-alanine and GABA consumption reduced the hornets' lifespan and completely inhibited their construction behavior; while proline induced a similar but more moderate effect. At low concentrations, these amino acids had no effect on hornet survival but did slow down the nest construction process. Using carbon isotopically labeled amino acids, we show that, unlike proline, ß-alanine is stored in most body tissues (brain, muscles, and fat body), suggesting that it is rapidly metabolized after consumption. Our findings demonstrate how a single amino acid can impact the fitness of a nectarivore insect.


Assuntos
Vespas , Aminoácidos , Animais , Larva , Néctar de Plantas , Prolina , Vespas/fisiologia , beta-Alanina/farmacologia , Ácido gama-Aminobutírico
3.
J Exp Biol ; 225(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35320357

RESUMO

The subjugation strategy employed by the jewel wasp is unique in that it manipulates the behavior of its host, the American cockroach, rather than inducing outright paralysis. Upon envenomation directly into the central complex (CX), a command center in the brain for motor behavior, the stung cockroach initially engages in intense grooming behavior, then falls into a lethargic sleep-like state referred to as hypokinesia. Behavioral changes evoked by the sting are due at least in part to the presence of the neurotransmitter dopamine in the venom. In insects, dopamine receptors are classified as two families, the D1-like and the D2-like receptors. However, specific roles played by dopamine receptor subtypes in venom-induced behavioral manipulation by the jewel wasp remain largely unknown. In the present study, we used a pharmacological approach to investigate roles of D1-like and D2-like receptors in behaviors exhibited by stung cockroaches, focusing on grooming. Specifically, we assessed behavioral outcomes of focal CX injections of dopamine receptor agonists and antagonists. Both specific and non-specific compounds were used. Our results strongly implicate D1-like dopamine receptors in venom-induced grooming. Regarding induction of hypokinesia, our findings demonstrate that dopamine signaling is necessary for induction of long-lasting hypokinesia caused by brain envenomation.


Assuntos
Baratas , Vespas , Animais , Comportamento Animal , Baratas/fisiologia , Dopamina/farmacologia , Agonistas de Dopamina/farmacologia , Humanos , Hipocinesia/induzido quimicamente , Instinto , Receptores Dopaminérgicos , Receptores de Dopamina D1 , Venenos de Vespas/efeitos adversos , Vespas/fisiologia
4.
J Chem Ecol ; 48(4): 370-383, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35257255

RESUMO

Kairomones are semiochemicals that are emitted by an organism and which mediate interspecific interaction that is of benefit to an organism of another species that receives these chemical substances. Parasitoids find and recognize their hosts through eavesdropping on the kairomones emitted from the by-products or the body of the host. Hemipteran insect pests feed on plant sap and excrete the digested plant materials as honeydew. Honeydew serves as a nutritional food source for parasitoids and a medium for micro-organisms whose activity induces the release of volatiles exploited by parasitoids for host location. The parasitoid Encarsia formosa preferentially parasitizes its host, the greenhouse whitefly, Trialeurodes vaporariorum, on tomato Solanum lycopersicum, but little is known about the chemicals that mediate these interactions. We investigated the olfactory responses of the parasitoid E. formosa to odours from honeydew and nymphs of T. vaporariorum in a Y-tube olfactometer. Arrestment behaviour of the parasitoid to honeydew and nymph extracts, as well as to synthetic hydrocarbons, was also observed in Petri-dish bioassays. We found that T. vaporariorum honeydew volatiles attracted the parasitoid E. formosa but odours from the whitefly nymphs did not. We also found that the parasitoid spent more time searching on areas treated with extracts of honeydew and nymphs than on untreated areas. Gas-chromatography-mass spectrometric analysis revealed that the honeydew volatiles contained compounds such as (Z)-3-hexenol, δ-3-carene, 3-octanone, α-phellandrene, methyl salicylate, ß-ocimene, ß-myrcene, and (E)-ß-caryophyllene which are known to be attractive to E. formosa. The cuticular extracts of the nymphs predominantly contained alkanes, alkenes, and esters. Among the alkanes, synthetic nonacosane arrested the parasitoid. Our findings are discussed in relation to how the parasitoid E. formosa uses these chemicals to locate its host, T. vaporariorum.


Assuntos
Hemípteros , Himenópteros , Lycopersicon esculentum , Vespas , Alcanos , Animais , Sinais (Psicologia) , Interações Hospedeiro-Parasita , Ninfa , Feromônios , Extratos Vegetais , Taiwan , Vespas/fisiologia
5.
BMC Ecol Evol ; 22(1): 31, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296235

RESUMO

BACKGROUND: The Japanese honeybee, Apis cerana japonica, shows a specific defensive behavior, known as a "hot defensive bee ball," used against the giant hornet, Vespa mandarinia. Hundreds of honeybee workers surround a hornet and make a "bee ball" during this behavior. They maintain the ball for around 30 min, and its core temperature can reach 46. Although various studies have been conducted on the characteristics of this behavior, its molecular mechanism has yet to be elucidated. Here, we performed a comprehensive transcriptomic analysis to detect candidate genes related to balling behavior. RESULTS: The expression levels of differentially expressed genes (DEGs) in the brain, flight muscle, and fat body were evaluated during ball formation and incubation at 46 °C. The DEGs detected during ball formation, but not in response to heat, were considered important for ball formation. The expression of genes related to rhodopsin signaling were increased in all tissues during ball formation. DEGs detected in one or two tissues during ball formation were also identified. CONCLUSIONS: Given that rhodopsin is involved in temperature sensing in Drosophila, the rhodopsin-related DEGs in A. cerana japonica may be involved in temperature sensing specifically during ball formation.


Assuntos
Rodopsina , Vespas , Animais , Abelhas/genética , Perfilação da Expressão Gênica , Japão , Vespas/fisiologia
6.
Sci Rep ; 12(1): 3372, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35233017

RESUMO

Polistes paper wasps are a widespread taxon inhabiting various climates. They build nests in the open without a protective outer layer, which makes them vulnerable to changing temperatures. To better understand the options they have to react to environmental variation and climate change, we here compare the thermoregulatory behavior of Polistes biglumis from cool Alpine climate with Polistes gallicus from warm Mediterranean climate. Behavioral plasticity helps both of them to withstand environmental variation. P. biglumis builds the nests oriented toward east-south-east to gain solar heat of the morning sun. This increases the brood temperature considerably above the ambience, which speeds up brood development. P. gallicus, by contrast, mostly avoids nesting sites with direct insolation, which protects their brood from heat stress on hot days. To keep the brood temperature below 40-42 °C on warm days, the adults of the two species show differential use of their common cooling behaviors. While P. biglumis prefers fanning of cool ambient air onto the nest heated by the sun and additionally cools with water drops, P. gallicus prefers cooling with water drops because fanning of warm ambient air onto a warm nest would not cool it, and restricts fanning to nests heated by the sun.


Assuntos
Vespas , Animais , Regulação da Temperatura Corporal , Comportamento de Nidação/fisiologia , Temperatura , Vespas/fisiologia , Água
7.
Environ Entomol ; 51(2): 440-450, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35137031

RESUMO

Seasonal temperatures select for eclosion timing of temperate insects and their parasitoids. In western North America, the fruit fly Rhagoletis zephyria Snow (Diptera: Tephritidae) is parasitized by the hymenopterous wasps Utetes lectoides (Gahan), an egg parasite, and Opius downesi Gahan, a larval parasite (both Braconidae). Eclosion of wasps should be timed with the presence of susceptible fly stages, but reports indicate U. lectoides ecloses in the absence of flies under no-chill conditions. Based on this, we tested the hypotheses that chill durations and no-chill temperatures both differentially regulate eclosion times of R. zephyria and its parasitic wasps. When fly puparia were chilled at ~3°C for 130-180 d, U. lectoides and O. downesi always eclosed on average later than flies. However, after 180-d chill, flies eclosed on average earlier than after 130- and 150-d chill, whereas eclosion times of U. lectoides and O. downesi were less or not affected by chill duration. When fly puparia were exposed to 20-22°C (no chill), U. lectoides eclosed before flies, with 88.9% of U. lectoides versus only 0.61% of flies eclosing. Taken together, findings show that eclosion times of flies are more sensitive to changes in chill duration than those of wasps. Flies are less sensitive than wasps to no-chill in that most flies do not respond by eclosing after no-chill while most wasps do. Our results suggest that shorter winters and longer summers due to climate change could cause mismatches in eclosion times of flies and wasps, with potentially significant evolutionary consequences.


Assuntos
Tephritidae , Vespas , Animais , Larva , América do Norte , Temperatura , Tephritidae/fisiologia , Vespas/fisiologia
8.
Sci Rep ; 12(1): 2835, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181732

RESUMO

Animals sometimes have prominent projections on or near their heads serving diverse functions such as male combat, mate attraction, digging, capturing prey, sensing or defence against predators. Some butterfly larvae possess a pair of long frontal projections; however, the function of those projections is not well known. Hestina japonica butterfly larvae have a pair of long hard projections on their heads (i.e., horns). Here we hypothesized that they use these horns to protect themselves from natural enemies (i.e., predators and parasitoids). Field surveys revealed that the primary natural enemies of H. japonica larvae were Polistes wasps. Cage experiments revealed that larvae with horns intact and larvae with horns removed and fitted with horns of other individuals succeeded in defending themselves against attacks of Polistes wasps significantly more often than larvae with horns removed. We discuss that the horns counter the paper wasps' hunting strategy of first biting the larvae's 'necks' and note that horns evolved repeatedly only within the Nymphalidae in a phylogeny of the Lepidoptera. This is the first demonstration that arthropods use head projections for physical defence against predators.


Assuntos
Borboletas/fisiologia , Cornos/fisiologia , Larva/fisiologia , Comportamento Predatório/fisiologia , Animais , Borboletas/anatomia & histologia , Larva/anatomia & histologia , Vespas/fisiologia
9.
Sci Rep ; 12(1): 1747, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110585

RESUMO

Hymenopteran parasitoids are well known for their ubiquitous diversity, important ecological roles and biocontrol potential. We report the first detailed documentation of mite predation by a parasitoid wasp, Bracon predatorius Ranjith & Quicke sp. nov., (Insecta: Hymenoptera), first case of obligate predatory behaviour in the family Braconidae and first case of mite feeding within the superfamily Ichneumonoidea. Larvae of a new wasp species are shown to develop entirely as predators of eriophyid mites that induce leaf galls in a commercially important plant. They display highly modified head capsule morphology that we interpret as being associated with this atypical life style. We propose that the new feeding strategy evolved separately from recently described entomophytophagy in another species of the same genus. The divergent larval morphological adaptations of both species indicate a high degree of evolutionary developmental plasticity in the developmental stage.


Assuntos
Comportamento Predatório/fisiologia , Vespas , Animais , Evolução Biológica , Himenópteros , Larva/fisiologia , Ácaros , Controle Biológico de Vetores , Vespas/classificação , Vespas/fisiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-35028724

RESUMO

The queen mandibular pheromone (QMP) identified from the honeybee is responsible for maintaining reproductive division of labour in the colony, and affects multiple behaviours. Interestingly, QMP inhibits reproduction not only in honeybee workers, but also in distantly related insect species such as fruit flies and bumblebees. This study examines whether QMP also affects worker reproduction in the common wasp Vespula vulgaris. Wasp workers were exposed to one of the following treatments: QMP, wasp queen pheromone (the hydrocarbon heptacosane n-C27), or acetone (solvent-only control). After dissecting the workers, no evidence that QMP inhibits development in V. vulgaris could be found. However, this study could confirm the inhibitory effect of the hydrocarbon heptacosane on ovary activation. The reason why non-social species such as the fruit fly and social species such as bumblebees and ants respond to the QMP, while the social wasp V. vulgaris does not, is unclear. The investigation of whether olfaction is key to sensing QMP in other insect species, and the detailed study of odorant receptors in other social insects, may provide insights into the mechanisms of response to this pheromone.


Assuntos
Feromônios , Vespas , Animais , Abelhas , Drosophila , Feminino , Hidrocarbonetos/farmacologia , Ovário , Feromônios/farmacologia , Reprodução , Olfato , Comportamento Social , Vespas/fisiologia
11.
J Chem Ecol ; 48(3): 323-336, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35099667

RESUMO

Orchids pollinated by sexual deception lure their specific male pollinators by sex pheromone mimicry. Despite the growing list of chemically diverse semiochemicals known to be involved, the chemical basis and flexibility of this extreme pollinator specificity are not fully understood. One promising but rarely applied tool is the synthesis and field testing of chemically related variants for investigating the structural specificity of the pheromone mimics. Here, we build on the discovery of the unusual semiochemical blend used by Drakaea micrantha to sexually lure its male Zeleboria thynnine wasp pollinator. This blend consists of a ß-ketolactone (drakolide) and two specific hydroxymethylpyrazines, presumably drawn from two distinct biosynthetic pathways. Here, we synthesized and tested the activity of various stereo- and structural isomers of the naturally occurring drakolide. Our study confirmed that in blends with the two pyrazines, both a mixture of stereoisomers, and the specific stereoisomer of the natural drakolide, elicit high rates of landings and attempted copulations. However, in the absence of pyrazines, both the number of responses and the level of sexual attraction were significantly reduced. When structural analogs were substituted for the natural drakolide, attractiveness and degree of sexual behaviour varied but were generally reduced. Based on our findings, and prior knowledge that related hydroxymethylpyrazines are active in other Drakaea spp., we conclude that the dual sex pheromone mimicry of D. micrantha likely evolved via initial changes in just one of the two biosynthetic pathways. Most plausibly, this involved modifications in the drakolides, with the pyrazines as a 'pre-adaption' enhancing the sexual response.


Assuntos
Orchidaceae , Atrativos Sexuais , Vespas , Animais , Flores/fisiologia , Masculino , Orchidaceae/química , Polinização/fisiologia , Atrativos Sexuais/química , Atrativos Sexuais/farmacologia , Relação Estrutura-Atividade , Vespas/fisiologia
12.
Pest Manag Sci ; 78(4): 1721-1728, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34997819

RESUMO

BACKGROUND: Here, we investigated changes in primary metabolism and cell death around oviposition sites in two hybrid clones of Eucalyptus with different degrees of resistance to Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae), as well as tolerance to water deficiency. RESULTS: We showed that apices of the resistant clone with oviposition had a higher content of amino acids, organic acids and the compound putrescine compared with those of the susceptible clone with oviposition. By contrast, apices of the resistant clone with oviposition had lower sugar and pyruvate organic acid content than those of the susceptible clone with oviposition. Small areas of necrosis were induced around the oviposition sites in the stem apices of Eucalyptus 24 h after infestation. The resistant clone developed larger necrotic areas that showed progressive increases 24-72 h after infestation compared with the susceptible clone, in which cell death was significantly lower and no changes were observed in necrotic area over time. Thus, the programmed death of cells around the egg, modulated by several amino acids, is likely the first defence response of Eucalyptus against L. invasa. CONCLUSION: Our results serve as the basis for the early identification of key metabolites produced in plants in defence against galling insects. © 2022 Society of Chemical Industry.


Assuntos
Eucalyptus , Vespas , Animais , Morte Celular , Feminino , Oviposição , Tumores de Planta , Vespas/fisiologia
13.
Philos Trans R Soc Lond B Biol Sci ; 377(1845): 20200437, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35000446

RESUMO

Reproductive division of labour is a hallmark of eusocial insects. However, its stability can often be hampered by the potential for reproduction by otherwise sterile nest-mates. Dominance hierarchy has a crucial role in some species in regulating which individuals reproduce. Compared with those in vertebrates, the dominance hierarchies in eusocial insects tend to involve many more individuals, and should require additional selective forces unique to them. Here, we provide an overview of a series of studies on dominance hierarchies in eusocial insects. Although reported from diverse eusocial taxa, dominance hierarchies have been extensively studied in paper wasps and ponerine ants. Starting from molecular physiological attributes of individuals, we describe how the emergence of dominance hierarchies can be understood as a kind of self-organizing process through individual memory and local behavioural interactions. The resulting global structures can be captured by using network analyses. Lastly, we argue the adaptive significance of dominance hierarchies from the standpoint of sterile subordinates. Kin selection, underpinned by relatedness between nest-mates, is key to the subordinates' acceptance of their positions in the hierarchies. This article is part of the theme issue 'The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies'.


Assuntos
Formigas , Vespas , Animais , Formigas/fisiologia , Comportamento Animal/fisiologia , Humanos , Reprodução/fisiologia , Predomínio Social , Vespas/fisiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-34826612

RESUMO

To explore and compare the expression patterns of venom components depending on post-capture periods, venom gland-specific transcriptome and proteome analyses were conducted for five model hymenopteran species at a series of time points after capture. Venom gland-specific genes with signal sequences were considered as putative venom component genes. Expression patterns of venom gland-specific genes in all the social wasps and bees examined varied considerably depending on the post-capture period. Higher numbers of venom genes exhibited a decreasing expression pattern than an increasing pattern as the capture period increased. For example, genes encoding most of the allergens (dipeptidyl peptidase 4, endocuticle structural glycoprotein, odorant-binding protein, phospholipase A1, A2, B1, serine protease, serine protease inhibitor and venom allergen 5), pain-producing factor (mast cell degranulating peptide), and paralyzing factor (neprilysin) commonly exhibited decreasing expression patterns in all of the hymenopteran species tested, except for some of the major venom genes in Apis mellifera and Bombus ignitus, which showed an increasing pattern. These findings indicate species- or group-specific variations in the expression patterns of major venom genes. Taken together, flash freezing in liquid nitrogen immediately after capture was determined to be the best way to obtain the most natural expression profiles of venom components in social wasp species, thus, enabling a better understanding of the toxic potential of venom in wasp sting accidents. This study provides guidance for establishing optimal protocols for venom gland isolation and venom extraction from wasps and bees that can ensure the most naturally represented venom composition.


Assuntos
Venenos de Abelha/genética , Abelhas , Proteínas de Insetos/genética , Venenos de Vespas/genética , Vespas , Animais , Venenos de Abelha/metabolismo , Abelhas/genética , Abelhas/fisiologia , Glândulas Exócrinas/fisiologia , Feminino , Regulação da Expressão Gênica , Proteínas de Insetos/metabolismo , Comportamento Social , Estresse Fisiológico , Fatores de Tempo , Venenos de Vespas/metabolismo , Vespas/genética , Vespas/fisiologia
15.
Insect Sci ; 29(2): 399-410, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34724344

RESUMO

To achieve successful development, female parasitoids, while laying eggs, introduce various virulence factors, mainly venoms, into host insects to manipulate their physiology. Although numerous studies have been conducted to characterize the components of venoms that regulate host immune responses, few systematic investigations have been conducted on the roles of venom proteins in host metabolic regulation. In this investigation, we characterized a novel venom protein in Pachycrepoideus vindemiae called glucose-6-phosphate dehydrogenase (PvG6PDH) and showed it has a vital role in regulating host carbohydrate metabolism. PvG6PDH encodes 510 amino acids and features a signal peptide and two conserved "G6PDH" domains. Multiple sequence alignment showed it has high amino acid identity with G6PDH from other pteromalids, and quantitative polymerase chain reaction analysis and immunofluorescent staining demonstrated a significantly higher expression of PvG6PDH in the venom apparatus compared with the carcass. We report that PvG6PDH contributes to parasitism by inhibiting the glucose-6-phosphate (G6P) metabolism of host Drosophila melanogaster, as demonstrated by PvG6PDH injection and RNA interference analysis. Further tests revealed that the accumulation of host G6P was caused by the transcriptional inhibition of G6P-metabolism-related genes. These findings greatly contribute to our understanding of venom-mediated host metabolic regulation, further laying the foundation for the development of venom proteins as biological agents for pest control.


Assuntos
Venenos de Vespas , Vespas , Animais , Drosophila melanogaster/metabolismo , Feminino , Glucose-6-Fosfato/metabolismo , Interações Hospedeiro-Parasita/genética , Venenos de Vespas/metabolismo , Vespas/fisiologia
16.
Insect Sci ; 29(2): 581-594, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34245664

RESUMO

Decisions made by foraging animals conform a complex process based on the integration of information from multiple external environmental stimuli and internal physiological signals, which in turn are modulated by individual experience and a detection threshold of each individual. For social insects in which foraging is limited to given age subcastes, individual foraging decisions may also be affected by ontogenetic shifts and colony requirements. We studied the short-term changes in foraging preferences of the generalist wasp Vespula germanica, focusing on whether the individual response to different resources could be influenced by the ontogenetic shifts and/or by social interaction with nestmates. We carried both laboratory and field experiments to confront worker wasps to a short-term resource switch between either protein or carbohydrate-based foods. We tested the response of (1) Preforager workers (no foraging experience nor interaction with other wasps), (2) Forager workers (experience in foraging and no colony feedback), and (3) Wild forager workers (foraging naturally and exposed to free interactions with nestmates). We evaluated the maxilla-labium extension response (MaLER) for laboratory assays or the landing response for field assays. We observed that for wasps deprived of colony feedback (either preforagers or foragers), the protein-rich foods acceptance threshold increased (and thus a lower level of foraging on that item was observed) if they had foraged on carbohydrates previously, whereas carbohydrates were accepted in all assays. However, wasps immersed in a natural foraging context did accept protein foods regardless of their first foraging experience and reduced the carbohydrates collected when trained on protein foods. We provide evidence that short-term changes in foraging preferences depend on the type of resource foraged and on the social interactions, but not on ontogenetic shifts.


Assuntos
Vespas , Animais , Retroalimentação , Vespas/fisiologia
17.
J Econ Entomol ; 115(1): 74-80, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34958100

RESUMO

Host plants indirectly affect parasitoid life-history traits via parasitoid hosts. Here, we evaluated the life-history traits of the parasitoid Aphelinus varipes emerging from the green peach aphid, Myzus persicae (Hemiptera: Aphididae), feeding on five commercially important vegetables. The results showed that A. varipes fed upon and parasitized maximum number of aphids grown on chili pepper, and least on cabbage. The emergence rate was the highest on chili pepper (100%) and lowest on crown daisy (71.1 ± 2.17%). Aphelinus varipes developed fastest on hosts reared on chili pepper (12.9 ± 0.02 d) and slowest on aphids reared on cabbage (14.1 ± 0.02 d). The body weight and body size of emerging wasp parasitoids and aphids were greatest on chili pepper and lowest on cabbage. Aphid body size positively affect parasitism, development time, and body size of the parasitoid. In conclusion, our results showed that the parasitoid A. varipes had variable life-history parameters, depending on the host plant species and host body size. The effects of host plant species on performance of M. persicae and its parasitoid A. varipes are discussed, along with the potential of using A. varipes to control M. persicae on different plants.


Assuntos
Afídeos , Vespas , Animais , Afídeos/parasitologia , Interações Hospedeiro-Parasita , Traços de História de Vida , Controle Biológico de Vetores/métodos , Plantas , Vespas/fisiologia
18.
J Therm Biol ; 101: 103097, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34879915

RESUMO

The aphid parasitoid, Aphelinus maculatus Yasnosh, was first documented in China in 2016. It is important to make clear of the effects of temperatures on the development of this aphid parasitoid for the future using as a aphid biological control agent. So the thermal requirements, lower developmental threshold (t), thermal constant (K), upper developmental threshold (Tm) and optimum developmental temperature (To) for the egg-mummy, mummy-adult and egg-adult periods of A. maculatus were established under the laboratory conditions. The studies were conducted at five constant temperatures (13, 18, 23, 28, and 33 °C) and with a 16 L: 8D photoperiod. Lower developmental threshold (t) and thermal constant (K) were estimated by fitting linear model. Upper developmental threshold (Tm) and optimal developmental temperature (To) were estimated by fitting Logan I non-linear model. The results turned out that the lower (t) and the upper developmental thresholds (Tm) for egg-adult period were 5.59 °C and 28.17 °C, respectively. The thermal constants (K) for egg-mummy, mummy-adult, and egg-adult periods were estimated at 121.51, 127.88, and 243.90 degree-days, respectively. The optimal developmental temperature (To) for egg-adult period was 27.45 °C calculated by the model, but the survival rate was only 40.68% at the temperature of 28 °C. The highest survival rate was 74.32% at temperature of 23 °C, implying that A. maculatus preferentially developed at the temperate regions of temperature.


Assuntos
Afídeos/crescimento & desenvolvimento , Afídeos/parasitologia , Temperatura , Vespas/fisiologia , Animais , Feminino , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Masculino , Controle Biológico de Vetores
19.
Toxins (Basel) ; 13(12)2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34941688

RESUMO

The social wasp Polybia paulista (Hymenoptera, Vespidae) is highly aggressive, being responsible for many medical occurrences. One of the most allergenic components of this venom is Antigen 5 (Poly p 5). The possible modulation of the in vitro immune response induced by antigen 5 from P. paulista venom, expressed recombinantly (rPoly p 5), on BALB/c mice peritoneal macrophages, activated or not with LPS, was assessed. Here, we analyzed cell viability changes, expression of the phosphorylated form of p65 NF-κB subunit, nitric oxide (NO), proinflammatory cytokines production, and co-stimulatory molecules (CD80, CD86). The results suggest that rPoly p 5 does not affect NO production nor the expression of co-stimulatory molecules in mouse peritoneal macrophages. On the other hand, rPoly p 5 induced an increase in IL-1ß production in non-activated macrophages and a reduction in the production of TNF-α and MCP-1 cytokines in activated macrophages. rPoly p 5 decreased the in vitro production of the phosphorylated p65 NF-κB subunit in non-activated macrophages. These findings suggest an essential role of this allergen in the polarization of functional M2 macrophage phenotypes, when analyzed in previously activated macrophages. Further investigations, mainly in in vivo studies, should be conducted to elucidate Polybia paulista Ag5 biological role in the macrophage functional profile modulation.


Assuntos
Antígenos/toxicidade , Macrófagos Peritoneais/efeitos dos fármacos , Venenos de Vespas/química , Vespas/fisiologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico , Fosforilação , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Venenos de Vespas/toxicidade
20.
Commun Biol ; 4(1): 1331, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824370

RESUMO

Huanglongbing (HLB) is a destructive disease of citrus primarily transmitted by the Asian citrus psyllid (ACP). Biocontrol of ACP is an environmentally sustainable alternative to chemicals. However, the risk of parasitoid rational application in ACP biocontrol has never been evaluated. Here we show, the dominant parasitoid of ACP, Tamarixia radiata, can acquire the HLB pathogen Candidatus Liberibacter asiaticus (CLas) and transmit it horizontally when probing ACP nymphs. If these ACP nymphs survive the probing, develop to adults and move to healthy plants, CLas can be transmitted to citrus leaves during feeding. We illustrate the formerly unrecognized risk that a parasitoid can potentially serve as a phoretic vector of the pathogen transmitted by its host, thus potentially diminishing some of the benefits it confers via biocontrol. Our findings present a significant caution to the strategy of using parasitoids in orchards with different infection status of insect-vectored pathogens.


Assuntos
Agentes de Controle Biológico , Citrus/microbiologia , Insetos Vetores/fisiologia , Liberibacter/fisiologia , Doenças das Plantas/microbiologia , Vespas/fisiologia , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia
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