Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 141
Filtrar
1.
Neotrop Entomol ; 53(5): 1055-1063, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39012616

RESUMO

A new species of Horismenus Walker, H. saturnus Schoeninger & Hansson (Hymenoptera: Eulophidae), is described from material reared from eggs of an unidentified species of Saturniidae (Lepidoptera). The new species is compared to H. cupreus (Ashmead, 1894), a species it is very similar to, and to H. ancillus (Brèthes), a species with the same type of host as H. saturnus. A total of 30 adult specimens developed from the eggs of Saturniidae. This is the second record of a Horismenus species parasitizing eggs of Saturniidae and the first record of this host from Brazil. Here, we provide a diagnosis and description of the new species including morphological and molecular characters, and multiple illustrations.


Assuntos
Óvulo , Vespas , Animais , Brasil , Vespas/classificação , Vespas/anatomia & histologia , Óvulo/parasitologia , Feminino , Florestas , Masculino , Lepidópteros/parasitologia
2.
Bull Entomol Res ; 114(1): 22-29, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38235530

RESUMO

Functional response and mutual interference are important attributes of natural enemies that should be analysed in species with the potential to be used as biological control agents in order to increase the predictive power of the possible benefits and/or consequences of their release in the field. Our main objective was to determine the functional response and mutual interference of Coptera haywardi (Oglobin), a pupal parasitoid of economically important fruit flies (Diptera: Tephritidae). The functional response of C. haywardi on A. ludens pupae corresponded to a type II model, with an attack rate of 0.0134 host pupa/h and a handling time of 1.843 h, which reveals a meticulous selection process of pupal hosts. The effect of mutual interference among foraging females was negatively correlated with increased parasitoid density in the experimental arena, showing a gradual decline in attack rate per individual female. The increase in the number of foraging females also had an impact on the number of oviposition scars per pupa and the number of immature parasitoids per dissected pupa, but not on the percentage of adult emergence or the sex ratio. Our results suggest that C. haywardi could act as a complementary parasitoid in the control of fruit fly pupae, since the random distribution of these pupae in the soil would decrease the possibility of aggregation and mutual interference between foraging females.


Assuntos
Himenópteros , Parasitos , Tephritidae , Feminino , Animais , Himenópteros/fisiologia , Pupa , Drosophila
3.
Rev. bras. entomol ; Rev. bras. entomol;68(1): e20230039, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1559493

RESUMO

ABSTRACT The rice stink bug, Tibraca limbativentris Stål (Hemiptera: Pentatomidae), is a significant pest of rice cultivation in Brazil and attacks plants during both vegetative and reproductive phases. Natural enemy surveys conducted in plantations located in Arari, Miranda do Norte, Matões do Norte, Santa Rita, and Viana (state of Maranhão, Brazil) led to the discovery of a new species of parasitoid, which is described in this study. Hexacladia lemosae Costa, Noyes & Machado sp. nov. (Hymenoptera: Encyrtidae) is the first species of its genus associated with T. limbativentris and develops as a gregarious endoparasitoid in adult stink bugs, occasionally in nymphs. The parasitoid emerges from the host while host is still alive.

4.
Insects ; 14(12)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38132574

RESUMO

Durrantia arcanella is a recurring pest insect of oil palm in Colombia. Because the biology and ecology of D. arcanella are unknown, it was proposed to determine the life cycle and foliar consumption under laboratory conditions. Furthermore, through sequential sampling for two and a half years, its population fluctuation and natural enemies were determined in Agustín Codazzi and El Copey (Cesar, Colombia). Also, temperature, precipitation, and relative humidity were registered. The life cycle of D. arcanella lasted 48.0 ± 10.1 days, the egg 8.0 ± 0.7 days, larva 24.2 ± 6.2 days, pre-pupa 1.5 ± 0.5 days, pupa 7.1 ± 0.9 days, and adult 7.2 ± 2.0 days. The larvae consumed 8.2 ± 5.3 cm2 of leaflets. Correlations were found between the population fluctuation in D. arcanella and the temperature in El Copey (ρ = -0.45; p < 0.0043), relative humidity in Codazzi (ρ = 0.33; p < 0.034), and with the natural control in both locations ((ρ = 0, 61; p < 0.000044) and (ρ = 0.42; p < 0.006)). These results suggest monitoring the pest populations in the second semester of the year and show the importance of promoting native natural enemies.

5.
Viruses ; 15(12)2023 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-38140687

RESUMO

Parasitoid wasps are fundamental insects for the biological control of agricultural pests. Despite the importance of wasps as natural enemies for more sustainable and healthy agriculture, the factors that could impact their species richness, abundance, and fitness, such as viral diseases, remain almost unexplored. Parasitoid wasps have been studied with regard to the endogenization of viral elements and the transmission of endogenous viral proteins that facilitate parasitism. However, circulating viruses are poorly characterized. Here, RNA viromes of six parasitoid wasp species are studied using public libraries of next-generation sequencing through an integrative bioinformatics pipeline. Our analyses led to the identification of 18 viruses classified into 10 families (Iflaviridae, Endornaviridae, Mitoviridae, Partitiviridae, Virgaviridae, Rhabdoviridae, Chuviridae, Orthomyxoviridae, Xinmoviridae, and Narnaviridae) and into the Bunyavirales order. Of these, 16 elements were described for the first time. We also found a known virus previously identified on a wasp prey which suggests viral transmission between the insects. Altogether, our results highlight the importance of virus surveillance in wasps as its service disruption can affect ecology, agriculture and pest management, impacting the economy and threatening human food security.


Assuntos
Parasitos , Vírus , Vespas , Animais , Humanos , Ecossistema , Viroma
6.
Environ Sci Pollut Res Int ; 30(47): 103851-103861, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37695481

RESUMO

Fungus-based biopesticides have been used worldwide for crop pest control as a safer alternative to chemical pesticides such as neonicotinoids. Both agrochemicals can be lethal and may also trigger side effects on the behavioral traits of non-target social insects, which play a crucial role in providing essential biological pest control services in agroecosystems. Here, we evaluated whether a commercial formulation of the entomopathogenic fungus Beauveria bassiana or the neonicotinoid imidacloprid causes mortality in foragers of Mischocyttarus metathoracicus. These social wasps are natural enemies of caterpillars and other herbivorous insects and inhabit both urban and agricultural environments in Brazil. We also tested whether wasps discriminate between biopesticide-exposed and unexposed conspecifics. Through a combination of laboratory (survival assay) and field experiments (lure presentation), along with chemical analyses (cuticular hydrocarbon profiles), we showed that topic exposure to the label rate of each pesticide causes a lethal effect, with the biopesticide exhibiting a slower effect. Moreover, wasps do not discriminate biopesticide-exposed from unexposed conspecifics, likely because of the similarity of their cuticular chemical profiles 24 h after exposure. Overall, the delayed lethal time at the individual level, combined with the indistinctive chemical cues of exposure and the lack of discrimination by conspecifics suggests that the fungal biopesticide may ultimately pose a threat to the colony survival of this predatory wasp.


Assuntos
Beauveria , Praguicidas , Vespas , Animais , Agentes de Controle Biológico , Hidrocarbonetos/análise , Controle Biológico de Vetores
7.
Parasitol Res ; 122(9): 1983-1991, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37341788

RESUMO

Flies of the Sarcophagidae family are widely distributed in the world, occupying different habitats. Some species have a high degree of synanthropy and are therefore often found in households in the urban environment. In Brazil, there is still little information related to the natural enemies of these insects in the urban environment, where population control is strictly chemical. Therefore, larvae and pupae of Peckia (Euboettcheria) collusor (Curran and Walley) (Diptera: Sarcophagidae) species were exposed in an urbanized location, and the presence and prevalence of parasitoids in the natural control of these immature stages was evaluated. We report for the first time the species Aphaereta pallipes (Say) (Hymenoptera: Braconidae) and Dirhinus anthracia Walker (Hymenoptera: Chalcididae), associated with P. (E.) collusor, highlighting the importance of these parasitoids in natural control in the urban environment, in addition to expanding the list of hosts for both parasitoid species and the distribution of this parasitoid-host interaction for Brazil and the Neotropical region.


Assuntos
Dípteros , Himenópteros , Sarcofagídeos , Animais , Brasil/epidemiologia , Larva
8.
Neotrop Entomol ; 52(2): 172-188, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36508149

RESUMO

Aphids are worldwide pests, and in South America, they harm many crops including winter cereals. In the 1970s, the rapid expansion of the wheat crop area in the subtropical region of South America led to growth of aphid populations. The wide availability of food, associated with the low effectiveness of natural biological control, put the aphid populations out of balance, requiring intensive use of insecticides. At the end of the decade, biological control programs of aphids were initiated in Argentina, Brazil, and Chile, including the importation of natural enemies (mainly parasitoids), followed by their laboratory rearing and field release. With decreased use of highly hazardous pesticides, biological control by introduced and already-present parasitoid species was enhanced. The program was very successful and aphid populations have been kept at low levels. This review article explores the history of this program and its current status. In modern day agriculture, with intense multiple cropping systems, adoption of several conservation practices, and increased cultivation of wheat in tropical regions, we discuss ways to keep this program effective to maintain aphid populations on cereal crops at low acceptable levels through employing biological control agents.


Assuntos
Afídeos , Grão Comestível , Animais , Controle Biológico de Vetores , Produtos Agrícolas , Triticum , Brasil
9.
J Insect Sci ; 22(3)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35596588

RESUMO

The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.


Assuntos
Himenópteros , Mariposas , Animais , Dieta , Feminino , Farinha , Humanos , Óvulo , Triticum , Zea mays
10.
Artigo em Inglês | MEDLINE | ID: mdl-35222555

RESUMO

BACKGROUND: Scorpionism is a worldwide problem that has already made thousands of victims, and multi-disciplinary approaches for controlling their populations are to be more successful. Hens are often mentioned as tools for controlling scorpions; however, systematic/experimental behavioral studies are not available. Moreover, there is no systematic information on the effect of scorpion venoms on hens. Using the venomous yellow scorpion Tityus serrulatus, the present study aimed to clarify the following aspects: (1) voracity of hens, (2) how hens react when stung, (3) the effect of scorpion stings on hen behavior during attacks, and (4) hen survivorship after feeding on scorpions. METHODS: We attracted hens with corn powder, offered them scorpions and then recorded the hen-scorpion interaction. To test the effects of the sting we manually removed the scorpion's telson. RESULTS: We found that some hens ate up to six scorpions within minutes. By means of an ethogram and drawings, we showed that they exhibited several aversive behaviors when capturing scorpions. Removal of the scorpion telson stopped the aversive reactions, which was not observed in the control group. Finally, hens did not exhibit atypical behaviors after 1, 7 and 30 days and were all alive after 30 days. CONCLUSION: This is the first empirical and video recorded study providing evidence that hens are clearly affected by scorpion venom but do not die. Therefore, they may have potential to be used in biological control of these arthropods.

11.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;28: e20210050, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360569

RESUMO

Scorpionism is a worldwide problem that has already made thousands of victims, and multi-disciplinary approaches for controlling their populations are to be more successful. Hens are often mentioned as tools for controlling scorpions; however, systematic/experimental behavioral studies are not available. Moreover, there is no systematic information on the effect of scorpion venoms on hens. Using the venomous yellow scorpion Tityus serrulatus, the present study aimed to clarify the following aspects: (1) voracity of hens, (2) how hens react when stung, (3) the effect of scorpion stings on hen behavior during attacks, and (4) hen survivorship after feeding on scorpions. Methods: We attracted hens with corn powder, offered them scorpions and then recorded the hen-scorpion interaction. To test the effects of the sting we manually removed the scorpion's telson. Results: We found that some hens ate up to six scorpions within minutes. By means of an ethogram and drawings, we showed that they exhibited several aversive behaviors when capturing scorpions. Removal of the scorpion telson stopped the aversive reactions, which was not observed in the control group. Finally, hens did not exhibit atypical behaviors after 1, 7 and 30 days and were all alive after 30 days. Conclusion: This is the first empirical and video recorded study providing evidence that hens are clearly affected by scorpion venom but do not die. Therefore, they may have potential to be used in biological control of these arthropods.(AU)


Assuntos
Animais , Venenos de Escorpião/intoxicação , Produtos Biológicos , Picadas de Escorpião , Escorpiões , Galinhas/metabolismo , Zea mays
12.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484790

RESUMO

Abstract Background: Scorpionism is a worldwide problem that has already made thousands of victims, and multi-disciplinary approaches for controlling their populations are to be more successful. Hens are often mentioned as tools for controlling scorpions; however, systematic/experimental behavioral studies are not available. Moreover, there is no systematic information on the effect of scorpion venoms on hens. Using the venomous yellow scorpion Tityus serrulatus, the present study aimed to clarify the following aspects: (1) voracity of hens, (2) how hens react when stung, (3) the effect of scorpion stings on hen behavior during attacks, and (4) hen survivorship after feeding on scorpions. Methods: We attracted hens with corn powder, offered them scorpions and then recorded the hen-scorpion interaction. To test the effects of the sting we manually removed the scorpions telson. Results: We found that some hens ate up to six scorpions within minutes. By means of an ethogram and drawings, we showed that they exhibited several aversive behaviors when capturing scorpions. Removal of the scorpion telson stopped the aversive reactions, which was not observed in the control group. Finally, hens did not exhibit atypical behaviors after 1, 7 and 30 days and were all alive after 30 days. Conclusion: This is the first empirical and video recorded study providing evidence that hens are clearly affected by scorpion venom but do not die. Therefore, they may have potential to be used in biological control of these arthropods.

13.
Acta sci., Anim. sci ; 44: e54128, 2022. mapas, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1366563

RESUMO

This study aimed to observe the attractiveness efficiency of trap boxes installed in collective shelters of stingless bee colonies (Melipona flavolineata, Melipona fasciculataand Scaptotrigona aff.depilis), as an alternative method for non-chemical control of tracuá carpenter ants (Camponotus atriceps). The study was conducted at Embrapa Amazônia Oriental, in Belém, Pará, Brazil, from March to August 2015. The results showed that the efficiency of this technique depended on the presence of bee colonies and on the bee species in the collective shelter. Overall, an efficiency of 40.6% was found in the capture of C. atricepsindividuals, which rose to 75% considering only collective shelters ofM. fasciculata colonies, and to 87.5% for collective shelters ofM. flavolineata. Trap boxes installed in collective shelters of S. depilisdid not attract any C. atricepsgroup or individuals. The use of trap boxes in collective shelters of stingless bee colonies of the genus Melipona (M. flavolineataand M. fasciculata) is an efficient alternative method of non-chemical control of tracuá carpenter ants (C. atriceps).(AU)


Assuntos
Formigas , Abelhas/crescimento & desenvolvimento
14.
Insects ; 12(12)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34940180

RESUMO

The generalist mirid predator Macrolophus basicornis may contribute to Integrated Pest Management (IPM) of Bemisia tabaci in tomato crops. It is important to know the compatibility of the chemicals used to control this pest with this promising biological control agent. Seven insecticides were tested to investigate their toxicity to the predator. For four of the products, the LC50 for adults were determined. Buprofezin, cyantraniliprole and spiromesifen did not cause lethality and were classified as harmless. Acetamiprid, bifenthrin, etofenprox + acetamiprid and pyriproxyfen + acetamiprid caused acute toxicity and were classified as harmful. LT50 for all harmful insecticides were relatively low, ranging from 1.8 to 3.2 days. Moreover, these four insecticides have low LC50, with acetamiprid (0.26 mg a.i. L-1) as the lowest, followed by bifenthrin (0.38 mg a.i. L-1), etofenprox + acetamiprid (4.80 mg a.i. L-1) and pyriproxyfen + acetamiprid (8.71 mg a.i. L-1). However, the calculated risk quotient (RQ) values demonstrated that these insecticides were mostly ecologically safe for this predator, except for acetamiprid, classified as slightly to moderately toxic. The present study can contribute to the use of M. basicornis as a biological control agent on tomato crops and to compatible use with the insecticides tested, according to IPM strategies.

15.
Acta biol. colomb ; 26(3): 466-469, sep.-dic. 2021.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360041

RESUMO

ABSTRACT In this work, the wasp Brachymeria podagrica is recorded for the first time for Colombia, a solitary parasitoid of larvae of the Peckia collusor fly. Third instar larvae of P. collusor were exposed to outdoor ambient conditions for 6 hours in the garden of the Tecnológico de Antioquia (Medellín, Colombia). 29 B. podagrica adults were obtained from the host pupae. Prevalence of parasitism was 14.5 %.


RESUMEN En este trabajo se reporta por primera vez a la avispa Brachymeria podagrica para Colombia y como parasitoide solitario de larvas de la mosca Peckia collusor. Los enemigos naturales fueron atraídos al exponer 200 larvas de P. collusor en tercer instar a condiciones ambientales naturales durante 6 horas el 16 de abril de 2015 en el jardín del Tecnológico de Antioquia (Medellín, Colombia). Como resultado, 29 adultos de B. Podagrica emergieron de las pupas. La prevalencia de parasitismo fue del 14,5 %.

16.
Zookeys ; 1061: 11-22, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720610

RESUMO

A new species of microgastrine wasp, Cotesiacassina Salgado-Neto, Vásquez & Whitfield, sp. nov., is described from southwestern Colombia in Tumaco, Nariño. This species is a koinobiont gregarious larval endoparasitoid, and spins a common mass of cocoons underneath the host caterpillars of Opsiphanescassina (Felder & Felder) (Lepidoptera, Nymphalidae), feeding on oil palm trees (interspecific hybrid Elaeisoleifera × E.guineensis) (Arecaceae). While superficially similar, both morphologically and biologically, to C.invirae Salgado-Neto & Whitfield from southern Brazil, the two species are distinct based on DNA barcodes, host species, geographical range and morphological characters.

17.
Semina ciênc. agrar ; 42(05): 2669-2684, set.-out. 2021. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1501865

RESUMO

Leaf-cutting ants of the genus Acromyrmex cause serious damage to cultivated forest areas. Some flies of the family Phoridae are known to parasitize them, and the result of this interaction can provide a promising basis for the management of these ants. This study was developed to record the parasitism and behavioral responses of Acromyrmex spp. leaf-cutting ants to parasitoid phorids in the municipality of Londrina-PR, Brazil. Visual examinations and collections of leaf-cutting ants and associated phorids were carried out between October/2019 and April/2020 in selected anthills and their trails, located on the campus of the State University of Londrina (UEL) and at the Botanical Garden of Londrina. The collected insects were preserved in 70% alcohol, for later identification of the species. The behavioral response of the ants to the parasitoids was recorded individually and collectively, following protocols cited in the literature. The frequencies of the different response behaviors exhibited by the attacked ants were compared using analysis of variance. The leaf-cutting ant species Acromyrmex coronatus and Acromyrmex crassispinus were found at the two evaluated sites. Myrmosicarius catharinensis was the only species of parasitoid phorid found, which attacked both ant species. Although the occurrence of M. catharinensis has been reported in other Brazilian states and its association with A. crassispinus recorded in Buenos Aires, Argentina, this is the first report of the occurrence of the phorid in the state of Paraná with a new association for the species A. coronatus. Under foraging action by the parasitoid, 63.5% of the ants exhibited only one behavioral response, while 36.5% showed two. Accelerated walking, attempting to "bite" the parasitoid, and adopting a 'C' posture were the most frequent behavioral responses to avoid parasitism [...].


Formigas-cortadeiras do gênero Acromyrmex causam sérios prejuízos em áreas florestais cultivadas. Algumas moscas pertencentes à família Phoridae são conhecidas por parasitá-las e o resultado dessa interação pode fornecer bases promissoras para o manejo destas formigas. Este estudo objetivou registrar o parasitismo e as respostas comportamentais de formigas-cortadeiras Acromyrmex spp. aos forídeos parasitoides no município de Londrina, PR. Entre outubro/2019 e abril/2020 foram realizadas inspeções visuais e coletas de formigas-cortadeiras e forídeos associados em formigueiros selecionados e suas trilhas, situados no Campus da Universidade Estadual de Londrina (UEL) e no Jardim Botânico de Londrina. Os insetos coletados foram preservados em álcool 70%, para posterior identificação das espécies. O registro comportamental das formigas aos parasitoides foi realizado a nível individual e coletivo, seguindo protocolos citados em literatura. As frequências entre os diferentes comportamentos de resposta exibidos pelas formigas atacadas foram comparadas por meio de análise de variância. As espécies de formigas cortadeiras Acromyrmex coronatus e Acromyrmex crassispinus foram encontradas nos dois locais avaliados. Myrmosicarius catharinensis foi a única espécie de forídeo parasitoide encontrada e atacou as duas espécies de formigas. Embora a ocorrência de M. catharinensis seja relatada para outros estados brasileiros e sua associação com A. crassispinus registrada em Buenos Aires - Argentina, este é o primeiro relato da ocorrência do forídeo no Paraná com nova associação para a espécie A. coronatus. Sob a ação de forrageamento do parasitoide, 63,5% das formigas apresentaram apenas uma resposta comportamental, enquanto 36,5% apresentaram duas respostas comportamentais [...].


Assuntos
Animais , Controle Biológico de Vetores/métodos , Controle de Insetos/métodos , Insetos/crescimento & desenvolvimento , Comportamento
18.
Semina Ci. agr. ; 42(05): 2669-2684, set.-out. 2021. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32770

RESUMO

Leaf-cutting ants of the genus Acromyrmex cause serious damage to cultivated forest areas. Some flies of the family Phoridae are known to parasitize them, and the result of this interaction can provide a promising basis for the management of these ants. This study was developed to record the parasitism and behavioral responses of Acromyrmex spp. leaf-cutting ants to parasitoid phorids in the municipality of Londrina-PR, Brazil. Visual examinations and collections of leaf-cutting ants and associated phorids were carried out between October/2019 and April/2020 in selected anthills and their trails, located on the campus of the State University of Londrina (UEL) and at the Botanical Garden of Londrina. The collected insects were preserved in 70% alcohol, for later identification of the species. The behavioral response of the ants to the parasitoids was recorded individually and collectively, following protocols cited in the literature. The frequencies of the different response behaviors exhibited by the attacked ants were compared using analysis of variance. The leaf-cutting ant species Acromyrmex coronatus and Acromyrmex crassispinus were found at the two evaluated sites. Myrmosicarius catharinensis was the only species of parasitoid phorid found, which attacked both ant species. Although the occurrence of M. catharinensis has been reported in other Brazilian states and its association with A. crassispinus recorded in Buenos Aires, Argentina, this is the first report of the occurrence of the phorid in the state of Paraná with a new association for the species A. coronatus. Under foraging action by the parasitoid, 63.5% of the ants exhibited only one behavioral response, while 36.5% showed two. Accelerated walking, attempting to "bite" the parasitoid, and adopting a 'C' posture were the most frequent behavioral responses to avoid parasitism [...].(AU)


Formigas-cortadeiras do gênero Acromyrmex causam sérios prejuízos em áreas florestais cultivadas. Algumas moscas pertencentes à família Phoridae são conhecidas por parasitá-las e o resultado dessa interação pode fornecer bases promissoras para o manejo destas formigas. Este estudo objetivou registrar o parasitismo e as respostas comportamentais de formigas-cortadeiras Acromyrmex spp. aos forídeos parasitoides no município de Londrina, PR. Entre outubro/2019 e abril/2020 foram realizadas inspeções visuais e coletas de formigas-cortadeiras e forídeos associados em formigueiros selecionados e suas trilhas, situados no Campus da Universidade Estadual de Londrina (UEL) e no Jardim Botânico de Londrina. Os insetos coletados foram preservados em álcool 70%, para posterior identificação das espécies. O registro comportamental das formigas aos parasitoides foi realizado a nível individual e coletivo, seguindo protocolos citados em literatura. As frequências entre os diferentes comportamentos de resposta exibidos pelas formigas atacadas foram comparadas por meio de análise de variância. As espécies de formigas cortadeiras Acromyrmex coronatus e Acromyrmex crassispinus foram encontradas nos dois locais avaliados. Myrmosicarius catharinensis foi a única espécie de forídeo parasitoide encontrada e atacou as duas espécies de formigas. Embora a ocorrência de M. catharinensis seja relatada para outros estados brasileiros e sua associação com A. crassispinus registrada em Buenos Aires - Argentina, este é o primeiro relato da ocorrência do forídeo no Paraná com nova associação para a espécie A. coronatus. Sob a ação de forrageamento do parasitoide, 63,5% das formigas apresentaram apenas uma resposta comportamental, enquanto 36,5% apresentaram duas respostas comportamentais [...].(AU)


Assuntos
Animais , Controle de Insetos/métodos , Insetos/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Comportamento
19.
Plants (Basel) ; 10(9)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579320

RESUMO

During the last few years, quinoa, a traditional Andean crop, has been cultivated at low elevations where pest pressure is high and farmers resort to intensive use of insecticides. This field study investigated the impact of four insecticides (cypermethrin, imidacloprid, teflubenzuron and emamectin benzoate) on insect pests of quinoa and their side effects on the arthropod community at the coastal level of Peru, by analysing the species composition, species diversity and population density. The arthropod community was examined with pitfall traps (for ground dwelling species), plant samplings (for pests and their natural enemies that inhabit the crop), and yellow pan traps (to catch flying insects). The results demonstrated that Macrosiphum euphorbiae, Frankliniella occidentalis and Spoladea recurvalis were efficiently controlled by cypermethrin and imidacloprid; the latter compound also showed long-term effects on Nysius simulans. Teflubenzuron and emamectin benzoate proved to be efficient to control S. recurvalis. Imidacloprid had the strongest adverse effects on the arthropod community in terms of species diversity, species composition and natural enemy density as compared to the other insecticides. Findings of this study may assist farmers intending to grow quinoa at the coastal level in selecting the most appropriate insecticides under an integrated pest management approach.

20.
Environ Entomol ; 50(5): 1088-1094, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34278413

RESUMO

Agroecosystems undergo frequent anthropogenic disturbance that may affect the diversity, community, and abundance of natural enemies living there. In the tropics, annual crops such as maize are planted two times (year-round crops) or one time (seasonal crops) per year. Little is known about how natural enemies of insect pests respond to maize agroecosystems planted one vs. two times during each annual cycle. The objective was to investigate the diversity and parasitism of egg parasitoids of the pest Dalbulus maidis (DeLong) (Hemiptera: Cicadellidae) in maize agroecosystems planted year-round and seasonally. Potted maize plants with D. maidis eggs were placed within these two maize agroecosystems to attract egg parasitoids during the maize-growing wet season in Mexico. In these two maize agroecosystems, similar levels of diversity were found, using the Shannon-Wiener index (H'). Communities of parasitic wasps were found attacking the eggs of D. maidis in both maize agroecosystems, but there were differences in the composition of these communities. In the year-round maize agroecosystem, Paracentrobia sp. near subflava (Girault) (Hymenoptera: Trichogrammatidae) was the most common, while Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae) was most common in the seasonal maize. A greater total abundance and total rate of parasitoid emergence were found in the year-round maize agroecosystem compared with the seasonal maize. In addition, a positive relationship between the number of D. maidis eggs and parasitoid abundance was found in both maize agroecosystems. However, a negative density dependence between the number of D. maidis eggs and the percentage of parasitism was found in both maize agroecosystems.


Assuntos
Hemípteros , Vespas , Animais , Óvulo , Estações do Ano , Zea mays
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA