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1.
Science ; 373(6554): 535-541, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326235

RESUMO

Interkingdom competition occurs between hymenopteran parasitoids and insect viruses sharing the same insect hosts. It has been assumed that parasitoid larvae die with the death of the infected host or as result of competition for host resources. Here we describe a gene family, parasitoid killing factor (pkf), that encodes proteins toxic to parasitoids of the Microgastrinae group and determines parasitism success. Pkfs are found in several entomopathogenic DNA virus families and in some lepidopteran genomes. We provide evidence of equivalent and specific toxicity against endoparasites for PKFs found in entomopoxvirus, ascovirus, baculovirus, and Lepidoptera through a mechanism that elicits apoptosis in the cells of susceptible parasitoids. This highlights the evolutionary arms race between parasitoids, viruses, and their insect hosts.


Assuntos
Entomopoxvirinae/fisiologia , Proteínas de Insetos/toxicidade , Lepidópteros/parasitologia , Lepidópteros/virologia , Proteínas Virais/toxicidade , Vespas/fisiologia , Animais , Apoptose , Evolução Biológica , Transferência Genética Horizontal , Genoma de Inseto , Interações Hospedeiro-Parasita , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Vírus de Insetos/fisiologia , Larva/genética , Larva/parasitologia , Larva/virologia , Lepidópteros/genética , Lepidópteros/metabolismo , Nucleopoliedrovírus/fisiologia , Spodoptera/genética , Spodoptera/metabolismo , Spodoptera/parasitologia , Spodoptera/virologia , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Vespas/crescimento & desenvolvimento
2.
PLoS One ; 16(7): e0254193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34288953

RESUMO

In recent years, the Asian gall wasp Dryocosmus kuriphilus has invaded chestnut trees and significantly affected the Portuguese chestnut production. Studies in other countries, such as Japan or Italy, have shown that the parasitoid Torymus sinensis can successfully achieve biological control of D. kuriphilus. Mathematical models help us to understand the dynamics of the interaction between the pest D. kuriphilus and its parasitoid T. sinensis and, consequently, they can help to implement measures that enhance crop pest management. In this work, the evolution of the density of D. kuriphilus and T. sinensis across time and space is studied through the numerical solution of models that include parameters based on observations made in Portugal. Simultaneous releases of the parasitoid are simulated at various locations and at different times. The results indicate that, in the case of a small and homogeneous orchard, biological control can be effective, but, in the case of extensive domains, the pest control is much more difficult to achieve. In order for biological control to be efficient, it is necessary to implement, in each chestnut-producing region, a collective strategy based on the annual monitoring of infestation levels.


Assuntos
Fagaceae/parasitologia , Modelos Teóricos , Controle Biológico de Vetores/métodos , Tumores de Planta/parasitologia , Vespas/parasitologia , Animais , Simulação por Computador , Larva/parasitologia , Estágios do Ciclo de Vida , Controle Biológico de Vetores/estatística & dados numéricos , Densidade Demográfica , Portugal , Pupa , Estações do Ano , Vespas/crescimento & desenvolvimento
3.
J Insect Physiol ; 132: 104271, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34175314

RESUMO

It is known that the progeny of post-diapause females of some insects are insensitive to diapause-inducing stimuli. In aphids the duration of the 'interval timer' (the restoration of the ability to diapause) decreases with temperature. However, the parameters of this temperature dependence are unknown. We investigated the restoration of the ability to undergo diapause in 9-16 sequential post-diapause generations of the egg parasitoid Trichogramma principium Sug. et Sor. (Hymenoptera: Trichogrammatidae) over a period of 120-150 days at different constant and variable temperatures. This revealed a strong linear correlation between mean temperature and the rate of the restoration of the ability to diapause. The lower temperature threshold of this dependence was not significantly different from that of the thermal dependence of the rate of preimaginal development. The restoration rate depended on the mean temperature for the whole period of development rather than on the temperature conditions during the development of the thermosensitive stages determining the incidence of diapause in the progeny. The results of this study indicate that the duration of the interval timer is determined by the rate of development (or, more generally, by the rate of metabolism) rather than by the mechanisms controlling the photothermal regulation of diapause.


Assuntos
Diapausa de Inseto/fisiologia , Temperatura , Vespas/fisiologia , Animais , Fotoperíodo , Vespas/crescimento & desenvolvimento
4.
Sci Rep ; 11(1): 12810, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140547

RESUMO

To clarify the life history of the Japanese spider wasp Dipogon sperconsus, bionomical studies using bamboo-cane trap nests were carried out in Japan. Based on weekly and consecutive daily surveys of trap nests and rearing of broods from collected nests, we evaluated the production of cells and eggs per day, prey spiders, and seasonal patterns of nesting activities. We found a relatively short critical period of switching from the summer generation into the overwintering generation. We also found that the voltinism is affected by the timing of egg production of the second generation in relation to this critical period. The developmental period for each generation and sex, voltinism and cell production per day were determined based on data for a large number of individuals for the first time.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Comportamento de Nidação/fisiologia , Vespas/crescimento & desenvolvimento , Vespas/fisiologia , Animais , Japão , Larva/crescimento & desenvolvimento , Óvulo/citologia , Comportamento Predatório , Pupa/crescimento & desenvolvimento , Estações do Ano , Aranhas , Temperatura
5.
Sci Rep ; 11(1): 11310, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050233

RESUMO

Ixodiphagus endoparasitoid wasps are natural tick enemies that can reduce their abundance. In this study, we investigated the presence of Ixodiphagus hookeri in Haemaphysalis concinna and Ixodes ricinus ticks in the Slovak Karst (southern Slovakia) and analysed the ecological and physiological relationships in the parasitoid-host system. Unfed H. concinna and I. ricinus nymphs harvested from vegetation were fed on rabbits. The engorged specimens were kept at 25 °C and 75% RH until the emergence of the adult wasps. For the first time in Europe, we found the presence of I. hookeri in two species of ticks collected in the same locality and compared their development in these tick species. The prevalence of wasps in H. concinna and I. ricinus during their spring activity was estimated at 10.64% and 27.78%, respectively. The presence of the wasps did not affect the duration of nymph feeding. Engorged wasp-infected ticks achieved higher body mass than non-infected specimens. In both tick species, there were no differences in the length of the development period and the number and sex ratio of adult I. hookeri. The analysed indicators and characteristics of the I. hookeri wasp-tick system can be used in research on tick control.


Assuntos
Interações Hospedeiro-Parasita , Ixodidae/parasitologia , Vespas/crescimento & desenvolvimento , Animais , Ecossistema , Ninfa/parasitologia , Coelhos , Eslováquia , Simpatria
6.
Sci Rep ; 11(1): 10087, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980970

RESUMO

Social insect colonies exhibit a variety of life history strategies, from the annual, semelparous colonies of temperate bees and wasps to the long-lived colonies of many ants and honeybees. Species introduced to novel habitats may exhibit plasticity in life history strategies as a result of the introduction, but the factors governing these changes often remain obscure. Vespula pensylvanica, a yellowjacket wasp, exhibits such plasticity in colony longevity. Multi-year (perennial) colonies are relatively common in introduced populations in Hawaii, while source populations in the western United States are typically on an annual cycle. Here, we use experiments and observational data to examine how diet, disease, nest thermal environment, and nest location influence colony longevity in a population with both annual and perennial colonies. Counter to our predictions, experimental feeding and warming did not increase colony survival in the winter in the introduced range. However, Moku Virus load and wasp colony density predicted colony survival in one year, suggesting a potential role for disease in modulating colony phenology. We also found that local V. pensylvanica colony density was positively correlated with Moku Virus loads, and that Arsenophonus sp. bacterial loads in V. pensylvanica colonies were positively associated with proximity to feral honeybee (Apis mellifera) hives, suggesting potential transmission routes for these poorly understood symbionts. The factors influencing colony longevity in this population are likely multiple and interactive. More important than food availability, we propose winter precipitation as a critical factor that may explain temporal and spatial variation in colony longevity in these invasive wasps.


Assuntos
Vírus de RNA/fisiologia , Vespas/crescimento & desenvolvimento , Vespas/virologia , Animais , Abelhas/crescimento & desenvolvimento , Ecossistema , Comportamento Alimentar , Hawaii , Densidade Demográfica , Vírus de RNA/genética , Estações do Ano , Temperatura , Carga Viral , Vespas/fisiologia
7.
Neotrop Entomol ; 50(1): 114-120, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33502718

RESUMO

In order to control the spread of the huanglongbing (HLB) disease in citrus plants, one of the main approaches is management of its vector, the Asian citrus psyllid, Diaphorina citri Kuwayama. The intensive use of chemicals to control the psyllid has caused concern due to the damage to the environment and human health, and biological control has been a more sustainable and environmentally safe strategy. For D. citri, the parasitoid wasp Tamarixia radiata Waterston has been used successfully in the state of São Paulo, Brazil, reducing populations of D. citri nymphs by up 80% in some municipalities. Mass rearing of wasps is required to provide efficient control, which implies that quality control is required, especially in storage and transportation. In most cases, the insects are not used on the same day of emergence, which makes it necessary to develop strategies to delay development without negatively affecting the wasps. Here, we evaluated the survival of T. radiata adults over eight different exposure times (2, 4, 6, 8, 10, 12, 14, and 16 days) in three different temperatures (7, 9, and 11°C). After these periods, they were transferred to climate chambers at 25°C and their survival curves over 30 days were analyzed. We concluded that adults can be maintained at 9°C for up to 6 days without significant damage to their survival during and after the exposure period, functioning well for D. citri IPM implementation.


Assuntos
Hemípteros/parasitologia , Temperatura , Vespas/crescimento & desenvolvimento , Animais , Brasil , Citrus , Ninfa/parasitologia , Controle Biológico de Vetores
8.
Sci Rep ; 11(1): 995, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441785

RESUMO

Controlling the cosmopolitan pest Drosophila suzukii (spotted wing drosophila) is a challenge for fruit growers. A promising agent for biological control of that pest are parasitoid wasps. Especially the widespread pupal parasitoid Trichopria drosophilae had shown the ability to parasitise the pest fly. However, as a biocontrol agent, parasitoids can only be effective when they prefer the pest to other insects. Until now studies have been inconsistent concerning the preference of T. drosophilae for D. suzukii and whether the preference depends on pupal volume. To clarify this inconsistency, we used video recordings of parasitisation experiments with a set up to observe the direct host preference of the parasitoid. Additionally, the volume of each host pupa was measured. We found significant preference of T. drosophilae for D. suzukii pupae independent of the pupal size and of the host species the wasps were reared on. The article also discusses the sex ratio and the success of the parasitoid in the different pupae characteristics.


Assuntos
Drosophila/crescimento & desenvolvimento , Himenópteros/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Vespas/crescimento & desenvolvimento , Animais , Feminino , Frutas/parasitologia , Especificidade de Hospedeiro/fisiologia , Larva/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Razão de Masculinidade
9.
Bull Entomol Res ; 111(2): 182-189, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32814599

RESUMO

Tetrastichus giffardianus is a gregarious koinobiont endoparasitoid of tephritids, including Ceratitis capitata, which is one of the most important fruit pests worldwide. The objective of this study was to evaluate the effect of constant temperatures on the biology and development of the egg-adult period of T. giffardianus in larvae/pupae of C. capitata to construct a fertility life table. The study was carried out in climatic chambers at constant temperatures of 15, 20, 25, 30, and 35 ± 1°C, 70 ± 10% relative humidity and a photophase of 12 h. Complete egg and larval development occurred only at temperatures of 20, 25, and 30°C. The mean longevity of males and females was inversely proportional to temperature. The time of development of the pre-imaginal period was influenced by temperature and ranged from 41 days at 20°C to 11 days at 25°C. The best T. giffardianus performance occurred at 25°C when the intrinsic rate of increase was 0.21, the mean generation time was 20.43 days, the time required to double the population was 3.33 days, and the finite rate of population increase (λ) was 1.23. The results of this study provided information for the establishment of mass rearing and an evaluation of the adaptability of T. giffardianus to different environments, which is necessary for the use of this parasitoid in the biological control of tephritid pests, particularly C. capitata.


Assuntos
Ceratitis capitata/parasitologia , Controle Biológico de Vetores , Vespas/crescimento & desenvolvimento , Animais , Fertilidade , Larva/parasitologia , Tábuas de Vida , Temperatura , Tephritidae
10.
Arthropod Struct Dev ; 60: 101005, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33212369

RESUMO

During metamorphosis, the insect CNS undergoes both structural and allometric changes. Due to their extreme de-embryonization and parasitism, the formation of the CNS in egg parasitoids occurs at the late larval stage. Our study provides the first data on the morphological and volumetric changes of the CNS occurring during the pupal development of the parasitic wasp Trichogramma telengai Sorokina, 1987 (Trichogrammatidae). The prepupal-pupal development includes fusion and concentration of ganglia achieved by the loss of connectives. Volumetric analysis shows that during the pupal development the absolute body volume and CNS volume gradually decrease. The brain and thoracic synganglion slightly increase in volume during the pupal period and extremely decrease from late pupa to adult. The CNS neuropil volume increases from prepupa to adult. The mean cell diameter also decreases during the metamorphosis of the nervous system. The cell body rind volume decreases during pupal development; this decrease correlates with the decrease in the number of cells on the one hand and increase in the neuropilar volume on the other hand.


Assuntos
Metamorfose Biológica , Vespas/crescimento & desenvolvimento , Animais , Sistema Nervoso Central/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento
11.
J Insect Sci ; 20(6)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33232487

RESUMO

Bacillus thuringiensis Berliner subsp. kurstaki (Btk) and Habrobracon hebetor Say are both biological control agents of Helicoverpa armigera Hubner. The present study evaluated their compatibility for combined application against this pest by examining the acceptability of Btk-inoculated hosts for H. hebetor females and testing for negative life-history impacts on developing progeny. Second-instar H. armigera larvae fed for 72 h on potted chickpea plants treated with three concentrations of Btk (LC15, LC35, and LC70) and were then used in bioassays of parasitoid development and parasitism behavior. Survival of parasitoids was significantly reduced, and immature development prolonged, on hosts fed chickpea plants treated with LC35 and LC70  Btk, but not on plants treated with LC15  Btk. Parasitoids failed to discriminate against hosts treated with LC15 or LC35  Btk in choice tests, but attacked fewer hosts treated with LC70  Btk, paralyzing and parasitizing more healthy hosts, and laying more eggs on them. In contrast, a no-choice test revealed that more hosts treated with LC35 and LC70  Btk were paralyzed compared with control or LC15-treated hosts, but the numbers of hosts parasitized and eggs laid did not vary among Btk treatments. Thus, females required an experience with healthy hosts, as they had in the choice test, to discriminate against diseased ones. We conclude that H. hebetor and Btk are compatible for joint application against H. armigera, which could potentially improve biological control of this pest.


Assuntos
Bacillus thuringiensis/química , Interações Hospedeiro-Parasita , Controle de Insetos , Mariposas/parasitologia , Controle Biológico de Vetores , Vespas/fisiologia , Animais , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Mariposas/crescimento & desenvolvimento , Vespas/crescimento & desenvolvimento
12.
J Insect Sci ; 20(5)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32986837

RESUMO

We report the discovery of the wasp Tachinobia repanda Boucek collected from egg sacs of the colonial spider Cyrtophora moluccensis (Doleschall) in Morobe Province, Papua New Guinea (PNG) by Lubin, Y.D. in 1980. This is the first record of T. repanda from egg sacs of a colonial spider. The likely host of this eulophid wasp was the larvae of a sarcophagid fly that parasitizes the egg sacs of these spiders. The 67 T. repanda collected were all females and varied little in body size. We suggest that this species is a gregarious hyperparasitoid.


Assuntos
Interações Hospedeiro-Parasita , Óvulo/parasitologia , Aranhas/parasitologia , Vespas/fisiologia , Animais , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Papua Nova Guiné , Aranhas/crescimento & desenvolvimento , Vespas/crescimento & desenvolvimento
13.
Proc Natl Acad Sci U S A ; 117(40): 24646-24648, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32963093

RESUMO

The Asian giant hornet (Vespa mandarinia) was recently detected in western British Columbia, Canada and Washington State, United States. V. mandarinia are an invasion concern due to their ability to kill honey bees and affect humans. Here, we used habitat suitability models and dispersal simulations to assess potential invasive spread of V. mandarinia We show V. mandarinia are most likely to establish in areas with warm to cool annual mean temperature, high precipitation, and high human activity. The realized niche of introduced populations is small compared to native populations, suggesting introduced populations could spread into habitats across a broader range of environmental conditions. Dispersal simulations also show that V. mandarinia could rapidly spread throughout western North America without containment. Given its potential negative impacts and capacity for spread, extensive monitoring and eradication efforts throughout western North America are warranted.


Assuntos
Ecossistema , Vespas/fisiologia , Distribuição Animal , Animais , Espécies Introduzidas/estatística & dados numéricos , América do Norte , Dinâmica Populacional , Temperatura , Vespas/crescimento & desenvolvimento
14.
Int J Mol Sci ; 21(17)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872177

RESUMO

In insect parasitoids, fatty acid synthases (FASs) have received less attention and their roles associated with lipogenesis loss are far from clear. Meteorus pulchricornis is a solitary endoparasitoid wasp of many larvae of lepidopteran pests. The lipid content during developmental stages of M. pulchricornis was measured; it was higher in the larval and pupal stages but declined from six-day-old pupae. Lipid accumulation constantly decreased in the adult stage, even after feeding on honey solutions. To investigate the roles of FASs in lipid synthesis in M. pulchricornis, four FAS genes (MpulFAS1~4) were identified from the transcriptome database of M. pulchricornis. All FAS genes included full-length open reading frames and shared 72-79% similarity with the sequences of Microplitis demolitor. qRT-PCR validation showed that all four FASs had the highest expression after the adult wasps were fed on honey diets. MpulFAS1 and MpulFAS2 reached their expression peaks at the adult stage but MpulFAS3 and MpulFAS4 peaked at the larval stage. To further study the function of FASs, dsRNA injection knocked down the expression of four MpulFASs and resulted in a significant decline of lipid content at the adult stage in M. pulchricornis. Results from this study suggest that M. pulchricornis adults cannot accumulate lipid content effectively and FASs may still contribute to lipid synthesis in the adult stage. This broadens the knowledge on the ability of lipid synthesis in parasitoid wasps and provides insight into the roles of FASs in insects with parasitic life-history traits.


Assuntos
Ácido Graxo Sintases/genética , Lepidópteros/parasitologia , Lipídeos/análise , Vespas/crescimento & desenvolvimento , Animais , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Parasita , Proteínas de Insetos/genética , Larva/genética , Larva/parasitologia , Fases de Leitura Aberta , Filogenia , Vespas/genética , Vespas/metabolismo
15.
J Insect Physiol ; 125: 104087, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634433

RESUMO

Trichopria drosophilae (Perkins) (Hymenoptera: Diapriidae) is a pupal parasitoid of drosophila flies recorded from several parts of the world. It is currently considered for augmentative biological programs to control the severe agricultural pest Drosophila suzukii (Matsumura) (Diptera: Drosophilidae). Since D. suzukii has invaded regions that experience zero and sub-zero winter temperatures, cold tolerance of the parasitoid is an important aspect to consider. We characterized low temperature tolerance and overwintering capacity of a colony of T. drosophilae collected in Northern Switzerland. We used copper-constantan thermocouples to determine the supercooling point and pre-freeze mortality. Moreover, we subjected honey-fed and unfed adult T. drosophilae as well as developing stages within their drosophila host to short- and long-term acclimation conditions and assessed the duration of their survival at low temperatures. Finally, we exposed adult and sub-adult stages to winter conditions in a semi-field experiment and evaluated their survival. We found that T. drosophilae is chill susceptible like D. suzukii, but adults froze and survived at colder temperatures than those reported for D. suzukii. Adult parasitoids could tolerate several days of exposure to sub-zero temperatures and could reproduce afterwards, whereas sub-adult stages could survive longer periods under these conditions. The provision of honey and water enhanced the survival of adults and long-term acclimation led to longer survival in all stages. The semi-field experiment supported the results of the laboratory tests. Based on these results we suggest that in Central Europe, T. drosophilae survives winters mainly in developing stages but adults are likely able to tolerate short periods of low spring temperatures.


Assuntos
Aclimatação , Temperatura Baixa , Drosophila/parasitologia , Vespas/fisiologia , Animais , Drosophila/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Pupa/parasitologia , Vespas/crescimento & desenvolvimento
16.
Insect Mol Biol ; 29(6): 569-577, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32715554

RESUMO

CRISPR/Cas9 gene editing is a powerful technology to study the genetics of rising model organisms, such as the jewel wasp Nasonia vitripennis. However, current methods involving embryonic microinjection of CRISPR reagents are challenging. Delivery of Cas9 ribonucleoprotein into female ovaries is an alternative that has only been explored in a small handful of insects, such as mosquitoes, whiteflies and beetles. Here, we developed a simple protocol for germline gene editing by injecting Cas9 ribonucleoprotein in adult N. vitripennis females using either ReMOT control (Receptor-Mediated Ovary Transduction of Cargo) or BAPC (Branched Amphiphilic Peptide Capsules) as ovary delivery methods. For ReMOT Control we used the Drosophila melanogaster-derived peptide 'P2C' fused to EGFP to visualize the ovary delivery, and fused to Cas9 protein for gene editing of the cinnabar gene using saponin as an endosomal escape reagent. For BAPC we optimized the concentrations of protein, sgRNA and the transfection reagent. We demonstrate delivery of protein cargo such as EGFP and Cas9 into developing oocytes via P2C peptide and BAPC. Additionally, somatic and germline gene editing were demonstrated. This approach will greatly facilitate CRISPR-applied genetic manipulation in this and other rising model organisms.


Assuntos
Proteína 9 Associada à CRISPR/genética , Edição de Genes , Células Germinativas/metabolismo , Proteínas de Insetos/genética , Mutagênese , Ribonucleoproteínas/genética , Vespas/genética , Animais , Sistemas CRISPR-Cas , Feminino , Masculino , Ovário , Vespas/crescimento & desenvolvimento
17.
Bull Entomol Res ; 110(5): 630-637, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32419690

RESUMO

Doryctobracon areolatus is a native parasitoid of the Neotropical region that presents the highest percentages of natural parasitism of fruit flies of the genus Anastrepha. In the Moscafrut Program SADER-SENASICA, located in Metapa de Domínguez, Chiapas, Mexico, a laboratory colony of this species is maintained on Anastrepha ludens, the Mexican fruit fly, with the aim to scale the production of the parasitoid up to massive levels. In order to eliminate unwanted emergence of adult flies during the rearing process, this study evaluated the effect of irradiation (at doses of 20, 30, 40, and 50 Gy) applied to eggs, and first and second instar larvae of A. ludens; all irradiated stages were subsequently exposed as second instar larvae to adult females of D. areolatus. Irradiation did not affect the eclosion of A. ludens eggs but, at doses of 40 and 50 Gy, it did cause delayed larval development and pupation, as well as lower larval weight. Adult fly emergence was suppressed at all doses, except in eggs irradiated at 20 Gy. Doses of 20 and 30 Gy applied to the eggs and larvae did not affect the emergence, survival, fecundity or flight ability of the emerged parasitoids, but the second instar larvae were easily handled during the rearing process. Our results suggest that D. areolatus can be successfully produced in second instar larvae of A. ludens irradiated at 30 Gy.


Assuntos
Tephritidae/parasitologia , Tephritidae/efeitos da radiação , Vespas/crescimento & desenvolvimento , Animais , Agentes de Controle Biológico , Feminino , Voo Animal/fisiologia , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/efeitos da radiação , Masculino , Óvulo/efeitos da radiação , Tephritidae/crescimento & desenvolvimento , Vespas/fisiologia
18.
J Insect Sci ; 20(3)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32458990

RESUMO

Survival and parasitism activity of Trichopria drosophilae Perkins adults, a cosmopolitan parasitoid of Drosophila spp., were studied under laboratory conditions using five constant temperatures at the lower range known for this enemy, from 4 to 20°C in 4°C increments. Drosophila suzukii Matsumura, an invasive pest of small fruits, was used as a host. Commercially available adult parasitoids were provided with 1) food and D. suzukii pupae; 2) food and no D. suzukii pupae; 3) no food and no pupae. The results show that adult females of T. drosophilae lived longer than males, and both generally benefitted from food supply. The highest level of survival was observed between 8 and 12°C for fed insects, irrespective of whether they were offered host pupae or not. The absence of food led to the highest mortality, but the parasitoid demonstrated considerably resistance to prolonged starvation. Successful parasitism increased steadily with temperature and reached the highest value at 20°C. Conversely, D. suzukii emergence rate was high after exposure of pupae to parasitoids at 4°C, while pupal mortality increased strongly with temperature until 12°C. The findings indicate that T. drosophilae is well adapted to the relatively cold conditions experienced in early spring and in autumn or at high elevations, when the host pupae could be largely available. The long lifespan of the adults and the ability to parasitize the host at low temperature make T. drosophilae potentially useful for the biocontrol of D. suzukii.


Assuntos
Drosophila/parasitologia , Interações Hospedeiro-Parasita , Controle de Insetos , Controle Biológico de Vetores , Vespas/fisiologia , Animais , Temperatura Baixa , Drosophila/crescimento & desenvolvimento , Feminino , Masculino , Pupa/crescimento & desenvolvimento , Pupa/parasitologia , Estações do Ano , Fatores Sexuais , Vespas/crescimento & desenvolvimento
19.
Genome Biol Evol ; 12(5): 701-714, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32271866

RESUMO

Relatively little is known about the processes shaping population structure in cooperatively breeding insect species, despite the long-hypothesized importance of population structure in shaping patterns of cooperative breeding. Polistes paper wasps are primitively eusocial insects, with a cooperative breeding system in which females often found nests in cooperative associations. Prior mark-recapture studies of Polistes have documented extreme female philopatry, although genetic studies frequently fail to detect the strong population structure expected for highly philopatric species. Together these findings have led to lack of consensus on the degree of dispersal and population structure in these species. This study assessed population structure of female Polistes fuscatus wasps at three scales: within a single site, throughout Central New York, and across the Northeastern United States. Patterns of spatial genetic clustering and isolation by distance were observed in nuclear and mitochondrial genomes at the continental scale. Remarkably, population structure was evident even at fine spatial scales within a single collection site. However, P. fuscatus had low levels of genetic differentiation across long distances. These results suggest that P. fuscatus wasps may employ multiple dispersal strategies, including extreme natal philopatry as well as longer-distance dispersal. We observed greater genetic differentiation in mitochondrial genes than in the nuclear genome, indicative of increased dispersal distances in males. Our findings support the hypothesis that limited female dispersal contributes toward population structure in paper wasps.


Assuntos
Cruzamento , Variação Genética , Genética Populacional , Vespas/genética , Animais , Feminino , Masculino , Vespas/crescimento & desenvolvimento
20.
Sci Rep ; 10(1): 7077, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341495

RESUMO

Neonicotinoid insecticides are associated with a decline in the diversity and distribution of bees and wasps (Hymenoptera: Aculeata). The effects of neonicotinoids on the metamorphosis of aculeates have never been addressed in detail; however, recent evidence suggests that neonicotinoids induce wing abnormalities. We hypothesized that the metamorphosis success of bees and wasps differs in response to contact exposure to field-realistic concentrations of neonicotinoid insecticides or in response to combined exposure to neonicotinoid insecticides and benzimidazole fungicides. We treated prepupae of the model crabronid wasp Pemphredon fabricii with field-realistic concentrations of four neonicotinoids, acetamiprid, imidacloprid, thiacloprid and thiamethoxam, and/or with the benzimidazole fungicide thiabendazole. Treatment with acetamiprid or imidacloprid decreased the pupation rates to only 39% and 32%, respectively. Treatment with thiacloprid or thiamethoxam did not affect the pupation rate when applied alone, but the subsequent treatment of thiacloprid- or thiamethoxam-treated prepupae with thiabendazole led to significant decreases in pupation rates. A high concentration of acetamiprid, which severely affected the pupation rates, had moderate effects on metamorphosis into adults, resulting in 53% metamorphosis success (as opposed to 95% metamorphosis success in the water-treated group). However, imidacloprid or thiamethoxam treatment resulted in only 5%-10% metamorphosis success into adults. Overall survival decreased in response to treatment with any of the neonicotinoids or benzimidazoles or their combinations, with extremely low survival (<2%) following combined treatment with imidacloprid and thiabendazole or thiamethoxam and thiabendazole. In conclusion, neonicotinoids alter insect metamorphosis success, which can be further potentiated by their combination with other agrochemicals, such as benzimidazoles.


Assuntos
Inseticidas/farmacologia , Metamorfose Biológica/efeitos dos fármacos , Neonicotinoides/farmacologia , Vespas/crescimento & desenvolvimento , Animais , Pupa/crescimento & desenvolvimento
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