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1.
Fungal Biol ; 120(5): 655-65, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27109363

RESUMO

A wild, forest-dwelling cockroach from the subfamily Ectobiidae (order Blattodea) in a nature reserve in Cavalcante, in the state of Goiás, Brazil, was found to be infected by a new, genetically distinct species in the Metarhizium flavoviride species complex that we describe here as Metarhizium blattodeae. The status of this fungus as a new species is supported by both multigenic sequence comparisons and protein profiles generated by MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry. This is one of the first reports of a naturally occurring fungal pathogen affecting any sylvatic (forest-dwelling) cockroach from any part of the world. M. blattodeae caused up to 96 % mortality of Periplaneta americana nymphs (a serious peridomestic cockroach species) after 10 d.


Assuntos
Blattellidae/microbiologia , Metarhizium/classificação , Metarhizium/isolamento & purificação , Micoses/microbiologia , Animais , Brasil , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Proteínas Fúngicas/análise , Genes de RNAr , Metarhizium/química , Metarhizium/genética , Microscopia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Polimerase II/genética , RNA Fúngico/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
2.
J Invertebr Pathol ; 136: 109-16, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27018147

RESUMO

Numerous isolates of an oomycete 'fungus', Leptolegnia chapmanii, are reported from Brazil for the first time. This aquatic pathogen was baited with Aedes aegypti sentinel larvae from stagnant, temporary bodies of water in selected locations under secondary tropical forest in and near the central Brazilian city of Goiânia and from more distant sites in the western and northern regions of the state of Goiás. Isolates were identified based on their morphological and developmental characters, comparative sequence data for the ITS and TEF loci, as well as their rapid activity against A. aegypti larvae. Taxonomic issues affecting the application of the name L. chapmanii and its typification are rectified. This study contributes to a better understanding of the presence and distribution of this oomycete in Brazil, its sequence-based identification, and of its potential as a biological agent against mosquito vectors.


Assuntos
Aedes/microbiologia , Peronospora/classificação , Animais , Brasil , Reação em Cadeia da Polimerase
3.
Acta Trop ; 158: 177-180, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26968351

RESUMO

Fungi are where one finds them, and if one seeks fungal pathogens affecting flies, then a garbage dump may be an ideal place to find both persistent, abundant fly populations and their fungal pathogens. An obvious fungal epizootic affecting the oriental latrine fly, Chrysomya megacephala (Diptera: Calliphoridae), was observed over several days in mid-February 2015 at the local garbage dump adjacent to the city of Cavalcante, northern Goiás. This site harbored large populations of both C. megacephala and a Musca sp. (Diptera: Muscidae) but only the population of oriental latrine fly was affected by any fungal pathogen and presented unusually dense populations of fresh cadavers. The fungus was identifiable as Pandora bullata (Entomophthorales: Entomophthoraceae) only after a very small number of characteristically decorated resting spores were found in these flies two months later; this represents the first Brazilian (and South American) record of this species. P. bullata is known previously from a small number of North American, European and Australian collections, all of which have included relatively abundant production of resting spores. We cannot dismiss the possibility that the extremely sparse formation of resting spores at this Brazilian site may be due to abiotic factors such as latitude (13°46'40.53″S), day length, ambient temperatures, or even the precipitation patterns in this mid-tropical montaine site. Epizootic events affecting calliphorids in Brazil strengthen the interest in entomophthoran pathogens for biological control of flies.


Assuntos
Dípteros/microbiologia , Entomophthorales/fisiologia , Animais , Brasil , Muscidae/microbiologia , Controle Biológico de Vetores
4.
Exp Appl Acarol ; 41(1-2): 27-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17237969

RESUMO

Development, reproduction, and life table parameters of the phytoseiid mite Neoseiulus idaeus Denmark & Muma preying on various stages of Tetranychus urticae Koch fed on papaya or snap bean plant were studied at 25 +/- 2 degrees C, 77 +/- 2% RH and 12L:12D photoperiod. Most characteristics of the predator, including the duration of the immature stages, preoviposition and oviposition periods, and female longevity did not differ significantly among the different food combinations. During the adult stage, N. idaeus females survived up to 14 days. The net reproductive rate, the mean generation time, and the intrinsic rate of natural increase of N. idaeus were very similar on all T. urticae stage--host plant combinations, ranging from 5.15 to 6.61 females, 10.15 to 12.62 days, and 0.150 to 0.168, respectively. These results indicate that T. urticae reared either on papaya or snap bean is an adequate prey for the development and reproduction of N. idaeus. Moreover, the current findings demonstrate that the host plant of T. urticae did not affect the predator. The implications of these results for the success of N. idaeus as a biological control agent of T. urticae in papaya orchards are discussed.


Assuntos
Carica/parasitologia , Ácaros/fisiologia , Controle Biológico de Vetores , Animais , Feminino , Estágios do Ciclo de Vida , Comportamento Predatório , Reprodução
5.
Neotrop. entomol ; 33(6): 799-803, Nov.-Dec. 2004. graf, tab
Artigo em Inglês | LILACS | ID: lil-512704

RESUMO

This study was conducted to search for potential mite predators to control phytophagous mites in papaya orchards. Bimonthly surveys, from January 1999 to February 2000, were carried out in two orchards, one in Silva Jardim (RJ), where pests are naturally controlled, and one at Linhares (ES), where pests are chemically controlled. All mite species collected from buds, new leaves, old leaves, and floral buttons of papaya trees and from weed leaves were quantified and identified to at least family level. Despite the relatively diverse mite fauna, we found representatives of only one family of predacious mites, i.e. Phytoseiidae. Among these, Neoseiulus idaeus Denmark & Muma was the most abundant and frequent during all seasons in the Linhares orchard, coinciding mainly with the fluctuations in abundance of tetranychid mites. Such occurrence in a production system with large use of acaricides, together with its favorable biological traits reported in the literature, lead us to recommend this species as a good candidate for biological control of papaya mite pests, especially Tetranychus urticae Koch.


Com o objetivo de selecionar ácaros predadores com potencial de controle de ácaros fitófagos do mamão, foram realizadas, de janeiro de 1999 a fevereiro de 2000, amostragens bimensais de ácaros em dois pomares, um orgânico (Silva Jardim, RJ) e outro com controle químico de pragas, doenças e invasoras (Linhares, ES). Todas as espécies presentes nas brotações laterais, folhas novas, folhas velhas e botões florais dos mamoeiros e nas folhas das plantas invasoras foram quantificadas e identificadas ao menos até família. Apesar da relativamente diversa fauna de ácaros, somente representantes de uma família de predadores, Phytoseiidae, foram encontrados. Dentre estes, Neoseiulus idaeus Denmark & Muma destacou-se por sua abundância e freqüência nas diferentes épocas do ano no pomar de Linhares, coincidindo principalmente com as flutuações na abundância dos tetraniquídeos. Tal ocorrência em um sistema de produção com grande emprego de acaricidas, aliada às características biológicas favoráveis dessa espécie, recomendam-na como candidata a agente de controle biológico de ácaros pragas do mamão, em especial Tetranychus urticae Koch.

6.
Neotrop. entomol ; 30(4): 631-639, Dec. 2001. ilus, tab
Artigo em Português | LILACS | ID: lil-514516

RESUMO

The phytophagous mites Panonychus ulmi (Koch) and Tetranychus urticae Koch (Tetranychidae) cause severe losses in apples in southern Brazil. An alternate means of managing both species, currently under way in orchards in Fraiburgo, SC, is the use of the predatory mite Neoseiulus californicus (McGregor). To understand how this predator interacts at the olfactive level with both prey on their host plants, we studied the responses of N. californicus on apple, Malus domestica (Borkham), as well as on three of the predator's alternate winter hosts (Sida rhombifolia L., Plantago tomentosa Lamarck and Taraxacum officinale Weber), in a Y-tube olfactometer. On apple, the tests demonstrated that N. californicus responded significantly to allelochemicals associated with previously-infested leaves with or without P. ulmi or T. urticae or their associated byproducts (feces, eggs, exuviae, and webs), as well as to those associated with previously-uninfested leaves + prey and its byproducts. The predator also responded to a mixture of volatile odors from previously-uninfested apple leaves with T. urticae byproducts. In relation to the location of T. urticae by N. californicus on its alternate winter host plants, we observed that the prey byproducts are more attractive to the predator on S. rhombifolia and P. tomentosa, whereas infested leaves of T. officinale with or without prey and its byproducts did not elicit any response. These results indicate that the volatiles from the host plant, as well as those from the prey and its byproducts, serve as cues in the prey location by N. californicus. Additionally, volatiles from the flowers of the three alternate host plants were highly attractive to the predator, which suggests that this stimuli could be involved in locating pollen, another of its food sources.


Os ácaros fitófagos Panonychus ulmi (Koch) e Tetranychus urticae Koch (Tetranychidae) causam sérios prejuízos à cultura da maçã no Sul do Brasil. Uma alternativa de manejo dessas espécies, atualmente em uso em pomares de macieira de Fraiburgo, SC, é o controle biológico com o ácaro predador Neoseiulus californicus (McGregor). Visando compreender como as interações do predador com ambas as presas em suas plantas hospedeiras são intermediadas ao nível olfativo, estudaram-se as respostas do predador tanto em macieira, Malus domestica (Borkham), como em algumas plantas invasoras de pomares: Sida rhombifolia L., Plantago tomentosa Lamarck e Taraxacum officinale Weber, hospedeiras alternativas de T. urticae no inverno. As respostas foram investigadas em olfatômetro em tubo na forma de Y. Em macieira, para ambas as presas, N. californicus respondeu significativamente aos aleloquímicos emanados de folhas atacadas isoladamente ou em conjunto com a presa e/ou seus subprodutos (fezes, ovos, teias e exúvias), assim como àqueles emanados de folhas sadias com a presa e seus subprodutos. N. californicus também foi atraído por folhas sadias de macieira contendo os subprodutos de T. urticae. Em relação à localização de T. urticae nas plantas hospedeiras alternativas, verificou-se que, em S. rhombifolia e P. tomentosa, os voláteis dos subprodutos do ácaro aparentemente exercem papel atrativo preponderante, enquanto não houve resposta a nenhum dos estímulos olfativos relacionados a T. officinale. Assim, no processo de localização de P. ulmi e T. urticae por N. californicus, tanto os estímulos olfativos da presa e de seus subprodutos como aqueles emitidos pela planta atacada por estes podem funcionar como sinalizadores para o predador localizar as colônias de ácaros fitófagos. Além disto, voláteis das flores das três plantas invasoras exerceram forte atratividade ao predador, o que sugere que este estímulo está envolvido na localização de pólen, outra de ...

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