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Sample records for mosca branca bemisia

  1. Potencial biótico da mosca-branca Bemisia argentifolii a diferentes plantas hospedeiras Biotic potential of Bemisia argentifolii to different host plants

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    Geni L. Villas Bôas

    2002-03-01

    Full Text Available A mosca-branca Bemisia argentifolii Bellows & Perring, 1994 causa danos em diversas culturas de importância econ��mica no Brasil. Este trabalho teve o objetivo de avaliar o potencial biótico do inseto nas plantas de abobrinha, feijão, mandioca, milho, poinsétia, repolho e tomate. Os experimentos foram conduzidos na Embrapa Hortaliças, em Brasília-DF, em câmaras climatizadas, à temperatura de 28 ± 2ºC e casa de vegetação, à temperatura ambiente (25 ± 8ºC, partindo-se de uma população de B. argentifolii, criada em poinsétia desde 1995. Repolho e feijão foram as plantas hospedeiras que apresentaram períodos pré-imaginais mais curtos, respectivamente 20,5 e 21,9 dias. As maiores porcentagens de mortalidade nesses períodos foram observadas em mandioca (97,9% e milho (94,2%. A razão sexual em geral foi favorável às fêmeas. O inseto apresentou valores muito próximos de r m (capacidade intrínseca de crescimento da população, variando de 0,18 em feijão a 0,13 em repolho, mostrando estar igualmente adaptado a estes hospedeiros. Resultados diversos foram observados em milho e mandioca, onde as fêmeas apresentaram alta mortalidade (> 90%, o que sugere baixa capacidade de utilização destes hospedeiros pela mosca-branca.The whitefly Bemisia argentifolii Bellows & Perring, 1994 has been causing damage in several economically important crops in Brazil. The purpose of this research was to determine the biotic potential of the insect in zucchini, dry bean, cassava, corn, poinsettia, cabbage and tomato. The experiments were carried out at the Experimental Station of Embrapa Hortaliças, located in Brasilia, in BOD chamber (28°C ± 2°C and greenhouse (25°C ± 8°C, with a whitefly population continuously reared on poinsettia plants since 1995. Cabbage and dry bean were the host plants with shorter pre-imaginal periods, 20.5 and 21.9 days respectively. The highest mortality in this periods was observed in cassava (97.9% and

  2. Indutores de resistência à mosca-branca Bemisia tabaci Biótipo B (GENN., 1889 (Hemiptera: Aleyrodidae em soja Resistance inducers to the whitefly Bemisia tabaci Biotype B (GENN., 1889 (Hemiptera: Aleyrodidae in soybeans

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    Jair Campos Moraes

    2009-10-01

    Full Text Available Objetivou-se, neste trabalho, avaliar o efeito da aplicação de indutores na resistência de duas cultivares de soja à mosca-branca Bemisia tabaci biótipo B. O experimento foi conduzido no Departamento de Entomologia - UFLA. As sementes de soja, cultivar IAC-19 e MONSOY-8001, foram previamente tratadas com o fungicida captan. Foram testados os seguintes tratamentos: T1- irrigação no solo, ao redor das plantas de cada vaso, de 250 mL de solução de ácido silícico a 1%; T2- pulverização das plantas, até o ponto de escorrimento, com solução a 0,3% de acibenzolar-s-methyl; T3- pulverização das plantas, até o ponto de escorrimento, com calda a 0,24% de pyraclostrobin+epoxiconazole e T4- testemunha. As plantas foram infestadas com 100 adultos da mosca-branca por vaso que liberados oito dias após a aplicação dos tratamentos. Avaliaram-se o número de ovos na face abaxial de cada folha, que foi marcada para posterior avaliação de ninfas; teores de taninos e de lignina; peso seco das raízes e da parte aérea. Não houve diferença para número de ovos e ninfas entre as cultivares de soja, porém, a viabilidade média de B. tabaci foi menor a cultivar IAC-19. O cultivar de soja IAC-19 demonstrou moderada resistência ao biótipo B de B. tabaci. A aplicação de silício ou acibenzolar-s-methyl induz um aumento no teor de lignina na cultivar de soja IAC-19.The objective of this paper was to evaluate the effect of the application of inducers on the resistance of two soybean cultivars to the whitefly B. tabaci Biotype B. The experiment was carried out at the Entomology Department - UFLA. The soybean seeds of cultivars IAC-19 and MONSOY-8001 were previously treated with Captan fungicide. The following treatments were tested: T1- irrigating the soil around the plants of each pot with 250 mL of solution of 1% silicic acid; T2- spraying of the plants, to the 'point of dripping', with a solution of 0.3% acibenzolar-s-methyl; T3- spraying of

  3. Resposta à mosca-branca (Bemisia tabaci e ao Tomato severe rugose virus de acessos de Solanum subgênero Leptostemonum Reaction to whitefly (Bemisia tabaci and Tomato severe rugose virus of Solanum subgenus Leptostemonum accessions

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    Miguel Michereff-Filho

    2012-09-01

    Full Text Available A mosca-branca (Bemisia tabaci e a infecção por espécies de Begomovirus são dois graves problemas fitossanitários que afetam a produção e qualidade do tomateiro (Solanum lycopersicum e de outras solanáceas de importância econômica. O presente trabalho foi conduzido sob condições controladas, em casa de vegetação, visando avaliar a resposta ao Tomato severe rugose virus (ToSRV e à mosca-branca (B. tabaci biótipo B de 36 acessos de espécies relacionadas ao gênero Solanum subgênero Leptostemonum (= grupo das solanáceas providas de espinhos. A inoculação de ToSRV foi realizada em mudas (43 dias após o semeio utilizando-se um colônia virulífera de B. tabaci biótipo B. Duas cultivares de tomateiro foram incluídas como testemunhas suscetíveis. A avaliação ao ToSRV foi feita de acordo com uma escala de severidade de sintomas e a presença de infecção sistêmica foi verificada via reação em cadeia da polimerase (PCR com 'primers' universais para espécies de Begomovirus. A maioria dos acessos apresentou uma resposta do tipo resistência ou quase imunidade ao ToSRV, não apresentando sintomas evidentes e nenhum indício de infecção sistêmica ou acumulação viral. Um grupo reduzido de acessos de S. stramonifolium, S. asperolanatum e S. jamaiscense apresentou uma resposta do tipo tolerância, caracterizada por baixa acumulação viral e sintomas suaves. O acesso S. mammosum 'CNPH 035', embora tolerante, foi o único que apresentou sintomas mais evidentes de infecção viral e acumulação de ToSRV. O mesmo grupo de 36 acessos foi avaliado em relação à colonização por B. tabaci em testes de livre escolha. Diferenças significativas foram observadas entre acessos para oviposição e o número de ninfas no quarto instar, indicando a presença de fatores de resistência ao inseto. Dez acessos de S. asperolanatum, S. stramonifolium, S. paniculatum e S. syssimbriifolium se mostraram completamente livres de oviposi

  4. UTILIZATION OF THE BEFENTHRIN IN CHEMICAL CONTROL OF WHITE FLY (Bemisia tabaci, Genn. 1889 IN BEAN CROPS AVALIAÇÃO DO BEFENTHRIN NO CONTROLE DA MOSCA BRANCA (Bemisia tabaci, Genn. 1889 EM FEIJOEIRO

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    Demétrio Martinez Palhares

    2007-09-01

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    The white fly (Bemisia tabaci, an important pest of bean crops, is known as vector of golden-yellow-mosaic virus in many regions in Brazil. In order to determine the efficiency of the befenthrin to control the white fly, a field experiment was carried out in Goiânia, State of Goiás, Brazil. The treatments and dosage in grams of active ingredient by ha were: befenthrin (2.5; 3.75; 5.0 and 6.25, metamidophós (420.0 and 600.0 and untreated check. Results obtained by this test permitted to conclude that befenthrin at experimented doses, presented similarity of control to the other used compound in different estimations realized, with control average superior to 96.0%.

    Com o objetivo de avaliar a eficiência do Befenthrin 25 CE, nas dosagens de 2,5 ; 3,75; 5,00 e 6,25g i.a/ha, no controle químico da mosca branca (Bemisia tabaci Genn., 1889 em feijoeiro, foi conduzido um experimento no Campo Experimental da Escola de Agronomia da Universidade Federal de Goiás - Goiânia, safra 91/92, utilizando como produto padrão o Metamidophós 600 BR nas dosagens de 420 e 600g i.a/ha. As pulverizações foram realizadas nos 7°, 14°, 21° e 28° dias após a emergência das plântulas, utilizando-se um pulverizador costal a CO2 com bico D3 gastando-se 250 litros de calda por ha. Dois dias após a última pulverização foi realizada a avaliação de eficiência, contando-se o número de ninfas vivas em 10 folíolos/parcela e, 10 dias após, fez-se a contagem do número de plantas com sintomas de “mosaico dourado” por parcela. Pelos resultados obtidos, conclui-se que o Befenthrin nas dosagens de 5,0 e 6,25g i.a./ha controlou eficientemente a praga, igualando-se ao metamidophós na dosagem de 600g i.a/ha, com a vantagem de menor toxicidade para mamíferos e também sob o ponto de vista ecol

  5. Atividade ovicida de extratos aquosos de meliáceas sobre a mosca branca Bemisia tabaci (Gennadius biótipo B em tomateiro Ovicidal activity of aqueous extracts of meliaceae on the silverleaf whitefly for tomato

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    Antonio Pancrácio de Souza

    2000-09-01

    Full Text Available A mosca branca Bemisia tabaci (Gennadius biótipo B atualmente é uma das principais pragas do tomateiro. O uso de extratos botânicos no controle desse inseto é uma alternativa promissora, mas que ainda precisa ser melhor pesquisada. O presente trabalho teve como objetivo determinar a bioatividade de extratos aquosos de folhas de Melia azedarach L. e de ramos de Trichilia pallida Swartz, sobre a mosca branca Bemisia tabaci (Gennadius biótipo B, criada em tomateiro. Foram realizados dois experimentos, avaliando-se a mortalidade e duração das fases de ovo e ninfa, após o tratamento da fase de ovo com os referidos extratos. No primeiro experimento, foram testadas as concentrações de 1 e 2% (p/v, acrescentando-se a concentração de 3% no segundo experimento. Em todos os tratamentos houve efeito ovicida, sendo o maior valor obtido com T. pallida a 3% (52,32%. Nos demais tratamentos, a mortalidade variou entre 16 e 37%. Os extratos aplicados sobre os ovos pouco afetaram a sobrevivência ninfal. Com exceção do tratamento com T. pallida a 2%, no primeiro experimento, em que a mortalidade ninfal foi de 26,42%, nos demais a mortalidade foi inferior a 16%. Em nenhum dos experimentos foi verificada alteração na duração dos períodos de incubação e ninfal.The silverleaf whitefly is today one of most important pests of tomato. The use of botanical extracts to control this insect is an interesting technique, but more research about it should be carried out. The objective of this work was to determine the bioactivity of aqueous extracts of Melia azedarach leaves and Trichilia pallida twigs on the silverleaf whitefly Bemisia tabaci (Gennadius biotype B, reared on tomato. Extracts were applied to eggs, and mortality and duration of egg and nymphal stages were evaluated in two experiments. In the first experiment, extracts were tested at concentrations of 1 and 2% (w/v and in the second experiment the concentration of 3% was added. The ovicidal

  6. INSETICIDAS APLICADOS VIA TRATAMENTO DE SEMENTES VISANDO AO CONTROLE DAS MOSCAS BRANCAS (Bemisia tabaci, GENN. E MINADORA (Liriomyza sp. NA CULTURA DO FEIJOEIRO CHEMICAL CONTROL OF THE WHITE FLY Bemisia tabaci GENN. AND LEAFMINER Liriomyza sp. IN BEAN CROPS BY SEED TREATMENTS

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    Antônio Lopes da Silva

    2007-09-01

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    Realizou-se o presente experimento no campo experimental da Escola de Agronomia da Universidade Federal de Goiás, de março a maio de 1993, para avaliar o controle das moscas brancas (Bemisia tabaci, GENN. e minadora (Liriomyza sp. na fase inicial da cultura do feijoeiro, com produtos aplicados via tratamento de sementes. Os tratamentos constaram de: imidacloprid 700 PM nas dosagens de 140, 210, 280 e 350 gramas de ingrediente ativo (i.a/l00 kg de sementes; carbosulfan + zinco 250 TS nas dosagens de 375 e 500g i.a./100kg de sementes, comparados com o carbofuran 350 TS na dosagem de 525 g i.a./100kg de sementes (padrão. Pelos resultados, concluiu-se que todos os tratamentos foram eficientes no controle da mosca minadora, com porcentagens de eficiência que variaram de 93 a 99%. Imidacloprid, a partir de 280g i.a./100kg de sementes, foi igual aos outros produtos em eficiência no controle da mosca branca, com porcentagens de controle variando entre 83 a 89%.

    A trial to control the white fly Bemisia tabaci, GENN. and leafminer Liriomyza sp. was carried out in Goiânia, state of Goiás. The treatments and dosages of the insecticides per 100kg of seed were: imidacloprid (140, 210, 280 and 350g a.i., carbofuran (525 g a.i., carbosulfan (375 and 500g a.i, plus an untreated check. The application of the treatments were made on the seeds. The results of the experiment showed that all insecticides were efficient in controlling the leafminer at all dosages tested and imidacloprid at the dosages of 280 and 350g a.i. per 100kg seed was similar in controlling the white fly in bean crops.

  7. Mosca-Branca, Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae em feijoeiro: Características gerais, bioecologia e métodos de controle

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    Anderson Silva

    2017-04-01

    Abstract. Common bean plants are infested by insects, which can ultimately affect the crop production before and after harvest, with estimated losses ranging from 33 to 86%. Among the insect pests infesting the common beans the whitefly Bemisia tabaci (Genn. stands out. This species cause direct injury by feeding on the plants and indirect injury by excreting sugary honeydew that is after colonized by the sooty mold. In addition, the most serious damage caused by B. tabaci is the transmission of virus diseases, especially the common bean golden mosaic, responsible for economic losses varying from 30 to 100%. This review aims at providing information on important aspects of B. tabaci including its geographical distribution, bioecology, population dynamics, host plants, and methods of pest control. We expect that this review can provide valuable subsidies for future studies on the whitefly in common beans.

  8. Avaliação de extratos vegetais no controle de mosca-branca, Bemisia tabaci biótipo B em abóbora Evaluation of plant extracts in the control of whitefly Bemisia tabaci biotype B in squash

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    Bruno Marcus Freire Vieira Lima

    2013-09-01

    Full Text Available A abóbora (Cucurbita moschata Duch. é uma cultura de importância para a agricultura familiar da região Nordeste do Brasil. No entanto, a ocorrência do prateamento das folhas da aboboreira ocasionado pela mosca-branca, Bemisia tabaci biótipo B limita sua produção, causando prejuízos aos agricultores. O objetivo deste trabalho foi avaliar a eficiência de extratos vegetais sobre o nível populacional de ninfas de mosca-branca em abóbora cv. Jacarezinho. O experimento foi instalado em campo experimental, em blocos casualizados, constituído de seis tratamentos e três repetições. As aplicações dos extratos vegetais foram feitas com intervalo de sete dias, fazendo-se uso de substâncias extraídas das seguintes plantas: canudo (Ipomoea carnea subsp. fistulosa, mamona (Ricinus communis L., tinguí (Mascagnia rigida Griseb, cardo-santo (Argemone mexicana L., e o óleo comercial Natuneem®. Todos os extratos vegetais obtiveram eficiência no controle de ninfas B. tabaci, sendo o R. communis (75,49%, M. rigida (73,99%, I. carnea (72,24%, óleo de nim (70,4% e A. mexicana (69,16%.The squash (Cucurbita moschata Duch. is an important crop for family farmers in the northeast of Brazil. However, the occurrence of leaf silvering caused by the whitefly, Bemisia tabaci biotype B, limits production, causing losses to farmers. The aim of this study was to evaluate the efficiency of plant extracts on the population levels of whitefly nymphs on the squash cv. Jacarezinho. The experiment was conducted at an experimental field, in a randomized block design consisting of six treatments and three replications. Applications of plant extracts were made at an interval of seven days, making use of substances extracted from the following plants: Ipomoea carnea subsp. Fistulosa, castor bean (Ricinus communis L., Tingui (Mascagnia rigida Griseb, cardo-santo (Argemone mexicana L., and the commercial oil product Natuneem ®. All of the plant extracts were

  9. Dinâmica Populacional de Mosca-Branca Bemisia tabaci (Genn. Biótipo B (Hemiptera: Aleyrodidae em Feijoeiro

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    Anderson Silva

    2014-04-01

    Abstract. This study aimed to evaluate the influence of abiotic factors on the population dynamics of the whitefly Bemisia tabaci (Genn., (Hemiptera: Aleyrodidae in three sowing seasons on bean plants (Phaseolus vulgaris L.. The assays were set up from June 2010 to April 2012 and conducted in the Departamento de Fitossanidade at FCAV/UNESP – Campus of Jaboticabal, SP. The studies of the population dynamics of B. tabaci biotype B were performed weekly through infestation assessments of eggs, nymphs and adults of the whitefly on 18 samplings, six for each sowing season: “winter”, “water” and “dry”, in addition to the influence of the abiotic factors weekly temperature and relative humidity (minimum, average and maximum and accumulated rainfall. These variables were correlated to the total number of eggs, nymphs and adults of the whitefly through Pearson’s linear correlation analysis. Among the obtained results, the population peaks of B. tabaci biotype B occurred at the “water” season, followed by “winter” and “dry” seasons, and the abiotic factors temperature and relative humidity influenced negatively the population dynamics of the whitefly.

  10. Transmissão do Cowpea mild mottle virus pela mosca branca Bemisia tabaci biótipo B para plantas de feijão e soja Transmission of the Cowpea mild mottle virus by whitefly Bemisia tabaci biotype B for plants of beans and soy

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    Julio Massaharu Marubayashi

    2010-06-01

    Full Text Available A necrose da haste da soja é causada por um vírus do gênero Carlavirus transmitido pela mosca branca Bemisia tabaci, também infectante de feijão e identificado como Cowpea mild mottle virus (CpMMV. Neste trabalho foram realizados testes para determinação do número de moscas-brancas B. tabaci biótipo B necessários para transmissão do vírus em feijoeiro e soja. Na sequência foram realizados dois outros testes, com 10 insetos por planta. Avaliaram-se períodos de acesso à aquisição (PAA de 'Jalo' para 'Jalo', e o efeito de períodos de acesso à inoculação (PAI. Foram visualmente constatados sintomas típicos do carlavírus como mosaico, clareamento de nervuras, necrose sistêmica e redução de crescimento. Houve transmissão do vírus para 'BT-2' de feijão e 'BRS-132' de soja com apenas um inseto por planta, sendo mais eficaz nesta última espécie. A taxa de transmissão do vírus foi maior com o aumento do número de insetos por planta. E o PAA foi determinado após 15' de tempo para aquisição, e o PAI com 5 min e aumentando os períodos de acesso a aquisição e inoculação aumentou-se a taxa de transmissão.The stem necrosis of soybean is caused by a virus of the Carlavirus and transmitted for the whitefly Bemisia tabaci, also infectad of beans and identified as Cowpea mild mottle virus (CpMMV. In this work biotype B for transmission of the virus in beans and soy had been carried through tests for determination of the number of necessary whiteflys B. tabaci. In the sequence two other tests had been carried through, with 10 insects for plant. Periods of access to the acquisition (PAA of 'Jalo' for 'Jalo', and the effect of periods of access to the inoculation (PAI had been evaluated increase. Visually typical symptoms of carlavirus had been evidenced as mosaic, veinclearing, sistemic necrosis and reduction of growth. It had transmission of the virus for 'BT-2' of beans and 'BRS-132' of soy with only one insect for plant

  11. Oviposition behavior of the silver leaf whitefly Bemisia tabaci biotype B on tomato; Comportamento de oviposicao da mosca-branca Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) biotipo B em tomateiro

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    Vendramim, Jose D. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. de Entomologia, Fitopatologia e Zoologia Agricola]. E-mail: jdvendra@esalq.usp.br; Souza, Antonio P. de [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Morfofisiologia. Lab. de Anatomia Humana]. E-mail: apsouza@nin.ufms.br; Ongarelli, Maria das G. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Lab. de Fisiologia e Bioquimica Pos-Colheita]. E-mail: mgong@esalq.usp.br

    2009-01-15

    The objective of this work was to evaluate the influence of the leaf surface, the insect geotropic behavior and the type of foliar trichome on Bemisia tabaci (Genn.) biotype B oviposition on tomato leaves. Bemisia tabaci females were confined in acrylic boxes in which tomato leaflets were fixed at the bottom and top part of the boxes to allow insects to access the leaf surface to be tested (adaxial and/or abaxial) in both no-choice and free choice tests. Oviposition was always higher when the leaf was offered at the top of the box and preferably at the abaxial leaf surface. The effects of leaf trichomes (glandular and non glandular) on B. tabaci oviposition was evaluated by offering the abaxial surface of tomato leaflets to females after a 70% ethanol wash to remove glandular exsudates against a control treatment (without a ethanol wash). Oviposition was concentrated mostly near to non glandular trichomes, showing whitefly females can discriminate among the trichomes. (author)

  12. Whitefly population dynamics in okra plantations Dinâmica populacional de mosca-branca em quiabo

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    Germano Leão Demolin Leite

    2005-01-01

    Full Text Available The control of whitefly Bemisia tabaci (Gennadius biotype B (Hemiptera: Aleyrodidae on okra (Abelmoschus esculentus L. consists primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to evaluate the spatial and temporal population dynamics of the whitefly B. tabaci biotype B on two successive A. esculentus var. "Santa Cruz" plantations. Leaf chemical composition, leaf nitrogen and potassium contents, trichome density, canopy height, plant age, predators, parasitoids, total rainfall and median temperature were evaluated and their relationships with whitefly on okra were determined. Monthly number estimates of whitefly adults, nymphs (visual inspection and eggs (magnifying lens occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant. Plants senescence and natural enemies, mainly Encarsia sp., Chrysoperla spp. and Coccinellidae, were some of the factors that most contributed to whitefly reduction. The second okra plantation, 50 m apart from the first, was strongly attacked by whitefly, probably because of the insect migration from the first to the second plantation. No significant effects of the plant canopy on whitefly eggs and adults distribution were found. A higher number of whitefly nymphs was found on the medium part than on the bottom part.O controle da mosca-branca Bemisia tabaci (Gennadius biótipo B (Hemiptera: Aleyrodidae em quiabeiro (Abelmoschus esculentus L. consiste principalmente no uso de inseticidas, em virtude da falta de informação sobre outros fatores de mortalidade. O objetivo deste trabalho foi compreender a dinâmica populacional, espacial e temporal da mosca-branca em dois cultivos sucessivos de quiabeiro "Santa Cruz". Avaliaram-se a composição química foliar, os níveis foliares de nitrogênio e de potássio, a densidade de tricomas, a altura de dossel, a idade de planta, predadores, parasitóides, pluviosidade total

  13. New experimental tools for bioassays with whitefly in laboratory Novas ferramentas experimentais para ensaios com mosca-branca em laboratório

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    Thiago Luis Martins Fanela

    2012-12-01

    Full Text Available The objective of this work was to develop an experimental kit for assessments of repellency, deterrence for oviposition, and insecticidal activity on adults of the whitefly Bemisia tabaci biotype B. The kit, which consisted of arenas and nebulizer, was effective for conducting bioassays, and the application of aqueous extracts by inhaler was adequate. The techniques are simple, cheap, and may contribute to research on this insect.O objetivo deste trabalho foi desenvolver um kit experimental para avaliações de repelência, deterrência à oviposição e atividade inseticida a adultos de mosca-branca, Bemisia tabaci biótipo B. O kit, constituído de arenas e nebulizador, foi eficaz para realização dos bioensaios, e a aplicação de extratos aquosos com o inalador foi adequada. As técnicas são simples, baratas e podem contribuir para as pesquisas com este inseto.

  14. Novos acessos de tomateiro resistentes à mosca-branca biótipo B New accessions of tomato resistant to whitefly biotype B

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    Maria Elisa de Sena Fernandes

    2009-11-01

    Full Text Available O objetivo deste trabalho foi selecionar novas fontes de resistência a Bemisia tabaci biótipo B, entre 34 acessos de tomateiro (Lycopersicon esculentum, do Banco de Germoplasma de Hortaliças da UFV. Avaliaram-se os números de adultos, ovos e ninfas por planta, além da densidade de tricomas. Detectaram-se diferenças entre os acessos nas variáveis avaliadas. Os acessos BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 e BGH-2125 apresentaram menor número de adultos, ovos e ninfas por planta e tiveram menor densidade de tricomas. A resistência dos acessos de tomate à mosca-branca foi associada a uma menor densidade de tricomas.The objective of this work was to evaluate resistance to Bemisia tabaci biotype B in 34 tomato (Lycopersicon esculentum accessions from the Banco de Germoplasma de Hortaliças of UFV. The number of adults, eggs and nymphs per plant besides of trichome density were evaluated. Differences between accessions were found for the evaluated variables. Accessions BGH-166, BGH-616, BGH-850, BGH-990, BGH-2102 and BGH-2125 presented less infestation of adults, eggs and nymphs per plant and showed lower trichome density. The resistance of these tomato accessions to whitefly was associated to a lower trichome density.

  15. Whitefly, aphids and thrips attack on cabbage Ataque de mosca-branca, pulgões e tripes em repolho

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    Germano Leão Demolin Leite

    2006-10-01

    Full Text Available The objective of this work was to investigate the relationships between predators and parasitoids, leaf chemical composition, levels of leaf nitrogen and potassium, total rainfall, relative humidity, daylight and median temperature on the intensity of whitefly, aphid, and thrips attack on cabbage. Whitefly, aphids and thrips population tended to proliferate in the final stage of plant or reached a peak population about 40 days after plantation. The whitefly and thrips tended to increase with an increase in the median temperature. A dependence of Cheiracanthium inclusum and Adialytus spp. populations on whitefly and aphids populations, respectively, was observed. No significant effect was detected between K and nonacosane leaf content and aphid population. However, an increase in leaf N content was followed by a decrease of this insect population. No significant relation was observed between leaf N, K and nonacosane and whitefly and thrips populations. Highest nonacosane levels were observed in plants 40 days after transplant, and relative humidity correlated negatively with nonacosane. Natural enemies, especially the parasitoid Adialytus spp. and the spiders can be useful controlling agents of the whitefly and aphids in cabbage. Median temperature can increase whitefly and thrips populations.O objetivo deste trabalho foi investigar as relações entre predadores, parasitóides, composição química foliar, níveis de nitrogênio e de potássio foliar, pluviosidade, umidade relativa, insolação e temperatura média na intensidade de ataque de mosca-branca, pulgão e tripes em repolho. As populações de mosca-branca, pulgões e tripes tenderam a aumentar no final do cultivo ou apresentaram pico 40 dias depois do transplantio. As populações de mosca-branca e tripes tenderam a aumentar sob temperaturas mais elevadas. As populações de Cheiracanthium inclusum e Adialytus spp. dependiam das populações de mosca-branca e pulg

  16. Development of leaf silvering in squash cultivars infested by silverleaf whitefly Prateamento das folhas em cultivares de aboboreira infestadas por mosca-branca

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    AL Lourenção

    2011-03-01

    Full Text Available The silverleaf whitefly Bemisia tabaci biotype B is one of the most harmful insect pests for agricultural and vegetable crops. Beside the direct damage, it transmits pathogenic virus and induces plant physiological disorders, such as the squash silverleaf disorder. In this research we evaluated the development of leaf silvering in squash cultivars submitted to artificial infestation of B. tabaci biotype B. An experiment was conducted under field conditions, in Campinas, São Paulo State, Brazil, during the season 2003-2004. The germplasm (Cucurbita spp. comprised of seven cultivars of summer squash and nine of bush squash. The experiment used a complete randomized blocks design, with 16 treatments (cultivars and five replications. Each plot consisted of two plants. The artificial infestation was done when the plants emitted the third pair of leaves, by transplanting soybean plants infested with silverleaf whitefly between the squash plots. The leaf silvering was evaluated every two or three days, using a rating scale varying from 1 (no symptom to 5 (leaves completely silvered. The highest level (5.0 was observed in 'Baianinha', 'Golden Delight', 'Caravela' and 'Arlika', while 'Novita' (2.5, 'Atlas' (2.0 and 'Atlanta AG-303' (1.5 showed light symptoms, indicating that these have low sensibility to this physiological disorder.A mosca-branca (Bemisia tabaci biótipo B é uma das mais nocivas pragas da agricultura. Além de danos diretos, transmite vírus e também induz desordens fisiológicas, como o prateamento-das-folhas-da-aboboreira. No presente trabalho, avaliou-se o prateamento em folhas de cultivares de aboboreiras, submetidas à infestação artificial de B. tabaci biótipo B. Um experimento foi conduzido em condições de campo, em Campinas-SP, no ano agrícola 2003-2004, com 16 cultivares de aboboreira (Cucurbita spp., sendo sete de hábito de crescimento rasteiro e nove de moita. Utilizou-se delineamento de blocos ao acaso, com 16

  17. Potencialidade inseticida de extratos aquosos de essências florestais sobre mosca-branca Insecticidal potential of aqueous extracts from arboreous species against whitefly

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    Giani Maria Cavalcante

    2006-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o potencial inseticida de extratos aquosos foliares de quatro essências florestais: algaroba (Prosopis juliflora, aroeira (Myracrodruon urundeuva, leucena (Leucaena leucocephala e sabiá (Mimosa caesalpiniifolia, preparadas em quatro concentrações, 3, 5, 7 e 10%. Foram avaliados três parâmetros em mosca-branca (Bemisia tabaci Gennadius 1889 (Hemiptera: Aleyrodidae: presença de compostos secundários, mortalidade de ovos e ninfas, e alterações na fertilidade do inseto. Determinou-se a presença de tanino nas quatro espécies, e de alcalóides em P. juliflora e M. urundeuva; as saponinas não foram detectadas em nenhuma espécie. Apenas os extratos de P. juliflora e L. leucocephala causaram mortalidade significativa de ovos e ninfas, tendo atingido, em alguns tratamentos, 75% de mortalidade sobre as ninfas. Esses extratos, com o de M. caesalpiniifolia, afetaram a fertilidade do inseto, tendo reduzido a taxa de reprodução, o tempo médio de geração e a taxa intrínseca de crescimento para três gerações de B. tabaci. Os efeitos variam de acordo com a concentração do extrato testado.The objective of this work was to assess the insecticidal potential of aqueous extracts of four arboreous species: mesquite (Prosopis juliflora, "aroeira" (Myracrodruon urundeuva, leucaena (Leucaena leucocephala and "sabiá" (Mimosa caesalpiniifolia, under four concentrations, 3, 5, 7 and 10%. Three parameters were evaluated in Bemisia tabaci (Gennadius 1889 (Hemiptera: Aleyrodidae: the presence of secondary compounds, mortality of eggs and nymphs, and alterations in insect's fertility. The presence of tannin was determined in all species, while alkaloids were observed only in P. juliflora and M. urundeuva; saponins were not detected in any species. Only the exctracts of P. juliflora and L. leucocephala caused significant mortality in eggs and nymphs, reaching, in some treatments, 75% mortality. These extracts and the

  18. Controle de mosca-branca com extratos vegetais, em tomateiro cultivado em casa-de-vegetação Use of plant extracts on whitefly control in tomato grown in greenhouse

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    Edson LL Baldin

    2007-12-01

    Full Text Available Visando buscar métodos alternativos no controle da mosca-branca Bemisia tabaci (Gennadius biótipo B em tomateiro, foram realizados testes de atratividade e preferência para oviposição em casa-de-vegetação, utilizando-se quatorze extratos aquosos a 3% (peso/volume. Os extratos foram preparados com partes de Azadirachta indica, Trichilia pallida,Chenopodium ambrosioides,Piper nigrum,Melia azedarach,Ruta graveolens,Ricinus communis,Mentha pulegium,Tagetes erecta,Eucalyptus citriodora,Cymbopogon nardus e Coriandrum sativum. Numa segunda etapa, os extratos mais eficientes em casa-de-vegetação foram observados em laboratório, a fim de avaliar o possível efeito sistêmico dos mesmos sobre ninfas da mosca-branca. Constatou-se que as plantas de tomateiro pulverizadas com extratos à base de folhas de M. pulegium e folhas e sementes de A. indica foram menos atrativas aos adultos do inseto. Plantas pulverizadas com extratos de folhas de A. indica e folhas + ramos de R. communis mostraram efeitos deterrentes à oviposição do inseto, reduzindo o número de ovos; em contrapartida, o extrato à base de folhas de C. nardus estimulou a oviposição da mosca-branca sobre as plantas. O uso dos extratos por via sistêmica não afetou o período de desenvolvimento (ovo-adulto da mosca-branca; entretanto, a presença de extratos de sementes e folhas de A. indica e de folhas de M. pulegium provocou aumento significativo na mortalidade de ninfas de B. tabaci biótipo B.Looking for alternative methods of control to silverleaf whitefly Bemisia tabaci (Gennadius biotype B in tomato, attractiveness and oviposition preference tests were accomplished in greenhouse using fourteen aqueous extracts at 3% (weight/volume. The extracts were prepared with parts from Azadirachta indica,Trichilia pallida,Chenopodium ambrosioides,Piper nigrum,Melia azedarach,Ruta graveolens,Ricinus communis,Mentha pulegium,Tagetes erecta,Eucalyptus citriodora, Cymbopogon nardus and

  19. Un Micoinsecticida como Agente de Control de la Mosca Blanca (Bemisia argentifolii Bellows y Perrings) en Jitomate (Lycopersicon esculentum Mill.)

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    Jesús Loera Gallardo; Ernesto Salgado Sosa

    2004-01-01

    Se evaluó la eficacia del hongo entomopatógeno Beauveria bassiana, elaborado como suspensión emulsificable a concentración de 2.1 x 1010 esporas mL-1 y aplicado en dosis de 1.0, 1.5 y 2.0 L ha-1, contra la mosca blanca Bemisia argentifolii en la variedad Flora Dade de jitomate. Se incluyó como testigo al insecticida endosulfán en concentrado emulsificable (350 g de i.a. L-1) y aplicado en dosis de 2.0 L ha-1. Se evaluó el número de ninfas vivas de mosca blanca encontradas en un área de 2 cm d...

  20. AVALIAÇÃO DE EXTRATOS VEGETAIS NO CONTROLE DE MOSCA BRANCA EM TOMATE

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    BRUNO MARCUS FREIRE VIEIRA LIMA

    2011-01-01

    Full Text Available In response to defense against herbivores, plants produce one versatile bioactive molecules synthesized in plant secondary metabolism. This paper aimed to evaluate the efficiency of plant extracts on the population level of whitefly nymphs on tomato cv. IPA 6, assess the number of fruits per treatment, fruit weight, ripeness and irregular pith. The experiment was installed in the field with the tomato crop IPA 6, block design, making use of substances extracted from plants, etanolic extract straw (Ipomoea carnea subsp. Fistulosa, etanolic extract castor (Ricinus communis L., aqueous extract tingui (Mascagnia rigida Griseb , aqueous extract Mexican poppy (Argemone mexicana L. and neem oil (Azadirachta indica A. Juss for the control of whitefly (Bemisia tabaci biotype B. The spraying was carried out by spraying, between 16 and 18 h, with an interval of seven days. Statistical analysis performed by WinStat and percentage of treatment efficiency calculated by Abbott (1925. The straw (72.41% and neem oil (67.26% were the most effective on nymphs. The number and weight of tomato fruits did not differ significantly between treatments. In relation to irregular maturation, extracts of I. carnea and M. rigida were significant. The extracts of I. carnea, M. rigida and A. Mexicana shown to be effective in controlling the pith. All plant extracts used in this experiment show efficiency on nymphs of B. tabaci.

  1. Efeito do cultivo do mamoeiro (Carica papaya L. em ambiente protegido sobre a ocorrência de ácaros fitófagos e moscas-brancas Effect of papaya (Carica papaya L. cultivated in a protected environment on the occurrence of phytophagous mites and whiteflies

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    Marineide Rosa Vieira

    2004-12-01

    Full Text Available O efeito do cultivo do mamoeiro em ambiente protegido foi estudado em três condições: sem cobertura e em dois telados construídos com tela de propileno branca, com malhas de 2 x 2 mm e 2 x 1 mm. Nessa área foram feitas avaliações na cultivar Baixinho de Santa Amália, contando-se o número de plantas com sintomas de ataque recente, para o ácaro branco Polyphagotarsonemus latus, com sintomas e presença de ácaros, para o ácaro rajado Tetranychus urticae e com presença de adultos ou ninfas nas folhas, no caso das moscas-brancas Trialeurodes sp., Bemisia tabaci biótipo B e uma terceira espécie não identificada. Para moscas-brancas, também foram realizadas contagens de ninfas e exúvias em laboratório. O cultivo em ambiente protegido favoreceu a sobrevivência e o desenvolvimento populacional das espécies estudadas, sendo que algumas possíveis causas são discutidas no texto. Considerando-se que o cultivo protegido pode ser uma boa alternativa para o controle de viroses, como o mosaico do mamoeiro, problema limitante para a cultura, estratégias de manejo de pragas nesses ambientes devem ser desenvolvidas, para viabilizar o seu uso.It was measured the effect of cultivating papaya cultivar "Baixinho de Santa Amália" in a protected environment and in three situations: without shade, and under screen shades of white polyethylene mesh sizes 2 x 2 mm or 2 x 1 mm. It was registered the number of plants with symptoms of recent attacks of the broad mite (Polyphagotarsonemus latus, symptoms and presence of the two-spotted spider mite (Tetranychus urticae and the presence on leaves of adults or nymphs of whiteflies (Trialeurodes sp., Bemisia tabaci biotype B and a third unidentified species. Whitefly nymph and exuviae numbers were also counted in the laboratory. Cultivation in a protected environment favored the survival and development of the species under study, and some possible reasons for these are discussed along the text. Since

  2. Nonpreference of whitefly for oviposition in tomato genotypes Não-preferência para oviposição de mosca-branca por genótipos de tomateiro

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    Luciana Cláudia Toscano

    2002-12-01

    Full Text Available The silverleaf whitefly is one of most important pests of tomato (Lycopersicon spp.. The use of host plant resistance to control this insect is an interesting, potentially useful technique, but in demand of more research. The objectives of this work were to evaluate the oviposition non-preference of Bemisia tabaci (Gennadius, 1889 biotype B for different tomato plant genotypes, evaluating the correlation between oviposition preference and pubescence in the genotypes, and analyzing the abaxial and adaxial surfaces of Lycopersicon pennellii leaflets under the scanning electron microscope. Four wild tomato genotypes, LA 716 (L. pennellii; PI 127826 and PI 127827 (L. hirsutum; PI 134417 (L. hirsutum f. glabratum, and two commercial genotypes, Santa Clara and Bruna VFN hybrid (L. esculentum were evaluated for number of eggs cm-2 in free and no-choice oviposition tests, using randomized block design and completely randomized design, respectively. The number of trichome was measured in 4 mm² and coefficients of correlation between number of trichomes and number of eggs were calculated. The wild genotypes LA 716 and PI 134417 were less preferred showing oviposition nonpreference resistance type in both tests. The Bruna VFN and Santa Clara were more preferred in free-choice test, while wild genotypes PI 127826 and PI 127827 were more preferred in no-choice test. L. pennellii leaflets presented glandular trichomes type IV in both surfaces. Santa Clara genotype presented higher density of trichomes, and B. tabaci biotype B presented higher preference to oviposition.A mosca-branca Bemisia tabaci (Gennadius, 1889 biótipo B é atualmente uma das principais pragas do tomateiro (Lycopersicon spp.. O uso de plantas resistentes para o controle deste inseto apresenta-se interessante, com grande potencial para Manejo Integrado de Pragas. Este trabalho teve por objetivos verificar a não-preferência para oviposição de B. tabaci biótipo B em genótipos de

  3. Efeito do controle químico da mosca-branca na incidência do vírus-do-mosaico-dourado e na produtividade do feijoeiro Effect of chemical control of whitefly on golden mosaic virus incidence and yield of common bean

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    Flávia Rabelo Barbosa

    2002-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de inseticidas no controle da mosca-branca (Bemisia argentifolii Bellows & Perring, 1994 na incidência do vírus-do-mosaico-dourado e na produtividade do feijoeiro. Utilizou-se de tratamento de sementes com imidacloprid ou thiamethoxam, e de pulverizações de inseticidas, em intervalos semanais. O experimento foi realizado no campo, em área irrigada, em Petrolina, PE, em blocos ao acaso, com cinco tratamentos e quatro repetições. Houve redução significativa no número médio de ovos, de ninfas e de adultos da mosca-branca e na porcentagem de infecção pelo vírus-do-mosaico-dourado do feijoeiro. A produtividade nas parcelas tratadas variou de 1.930 a 2.405 kg/ha, enquanto na testemunha foi de 1.490 kg/ha. Não foi observada diferença significativa entre os tratamentos, no número de vagens/planta e peso de 100 sementes.The objective of this work was to evaluate the effect of insecticides on the control of whitefly (Bemisia argentifolii Bellows & Perring, 1994, on golden mosaic virus incidence and on common bean yield. Seed treatment with the insecticides imidachloroprid or thiamethoxam followed by insecticide sprays at weekly internals were used. The experiment was conducted in a randomized complete block design in an irrigated area in Petrolina, PE, Brazil, with five treatments and four replicates. The chemical control decreased significantly the number of eggs, nymphs and adults, and also the percentage of infection by the golden mosaic virus in the bean crop. Grain yields for chemical treatments in the tilled plots ranged from 1,930 to 2,405 kg/ha, while the control yielded 1,490 kg/ha. There were no significant differences for number of pods per plant and for 100-seed weight.

  4. Interação entre inseticidas e umidade do solo no controle do pulgão e da mosca-branca em algodoeiro Interaction between insecticides and soil moisture in the control of whitefly and aphid in cotton

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    Jorge Braz Torres

    2008-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o controle exercido por tiametoxam e pimetrozine, em aplicação foliar ou ao solo, sobre Bemisia tabaci e Aphis gossypii, em algodoeiro, e determinar a interação entre formas de aplicação e a umidade do solo, em diferentes intervalos após a aplicação. Foram aplicados inseticidas via pulverização ou esguicho ao solo, em plantas de algodoeiro submetidas a três faixas de umidade do solo. Os inseticidas foram testados separadamente, em arranjos fatoriais, com formas de aplicação (tiametoxam, pragas (pimetrozine e teores de umidade no solo como fatores de variação, com as avaliações repetidas no tempo. Foram realizadas avaliações após 3 horas e aos 3, 6, 12, 24 e 32 dias após a aplicação. Os inseticidas, em pulverização, apresentaram controle superior a 80%, até 6 dias depois da aplicação, para mosca-branca e pulgão. O uso de tiametoxam com esguicho, na menor faixa de umidade, propiciou controle inferior a 60%, no dia da aplicação, superior a 90%, aos 3 e 6 dias, e superior a 80%, aos 12 dias após aplicação. O grau de estresse hídrico em que se encontra a planta é importante para a escolha do inseticida e da modalidade de aplicação mais adequados ao controle das pragas avaliadas.The objective of this work was to evaluate the control, in cotton plants, of Bemisia tabaci and Aphis gossypii by thiamethoxam and pymetrozine, with foliar or soil drench applications, and to determine the interaction between application method and soil humidity, in different intervals after insecticide application. Insecticide application consisted of foliar spray and soil drench, using cotton plants submitted to three levels of soil moisture. The insecticides were tested separately, in factorial arrangements, with application methods (thiamethoxam, pest species (pymetrozine and soil moisture levels, as treatments, with repeated measures on time. Evaluations were carried out after 3 hours, and at 3

  5. Qualidade de híbridos de melão após a aplicação de imidacloprid para controle de mosca-branca Fruit quality of hybrid melons after application of imidacloprid to control whitefly

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    Geomar G. da Silva

    2000-11-01

    Full Text Available Com o objetivo de avaliar a qualidade de diferentes híbridos de melão após a aplicação do inseticida imidacloprid via fertirrigação e pulverização para o controle da mosca-branca (Bemisia argentifolii Bellows & Perring, foi conduzido um ensaio na região agrícola de Mossoró-Açú-RN. As características avaliadas foram: população de insetos, produtividade, firmeza de polpa, sólidos solúveis, acidez, pH, açúcares totais, redutores e não redutores. O delineamento experimental foi blocos completos em parcelas subdivididas com quatro repetições. As parcelas foram constituídas pelos métodos de aplicação do inseticida (fertirrigação, pulverização e controle sem aplicação de inseticidas. As subparcelas foram ocupadas pelos três híbridos utilizados no experimento (Orange Flesh, AF 682 e Hy-Mark. O método de aplicação do inseticida teve efeito significativo na produção dos híbridos e o conteúdo de açúcares redutores. Houve aumento na produção do melão de 20,52% (fertirrigação e 13,54% (pulverização, quando comparados à testemunha.With the objective of evaluating fruit quality of hibrid melons after application of imidacloprid by fertirrigation and spraying to control whitefly (Bemisia argentifolii Bellows & Perring, a research was carried out at the agricultural region of Mossoró-Açu, Brazil. A randomized complete block design in a split-plot scheme with four replications was used. The methods of application of imidacloprid (fertirrigation, spraying and control were used in the plots and in the split-plot the melon hibrids (Orange Flesh, AF 682 and Hy-Mark were planted. Evaluation of insect population, melon fruit yield, pulp firmness, soluble solids contents, acidity, pH, total and, reducing and non reducing sugar content were analyzed. The methods of insecticide application of imidacloprid had a significant effect on fruit and in reducing sugar contents. There was an increasing on melon fruit yield of

  6. Distribuição vertical e setorial das ninfas de mosca-branca nas folhas do meloeiro Vertical and sectorial distribution of whitefly nymphs on melon leaves

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    Francisco Roberto de Azevedo

    2003-09-01

    Full Text Available Foram realizados estudos, no campo experimental de Pacajús, da Embrapa Agroindústria Tropical, para observar a distribuição espacial das ninfas de Bemisia argentifolii Bellows & Perring (Hemiptera: Aleyrodidae, entre as folhas e nas folhas da rama do meloeiro. Para estudo da distribuição entre as folhas, foram amostradas aleatoriamente, as folhas presentes no intervalo entre a quinta e a vigésima folha. A contagem das ninfas foi realizada semanalmente aos 49; 56 e 63 dias após o plantio, retirando, com o auxílio de um vasador de cortiça, um disco foliar de 2,8 cm². Foi observada uma maior concentração de ninfas entre a oitava e a décima folha, contada a partir da extremidade da rama do meloeiro, sendo, portanto, a melhor folha para ser amostrada. O estudo da distribuição setorial nas folhas do meloeiro foi feito amostrando-se aleatoriamente as folhas em campo e subdividindo-as em quatro setores, delimitados pela nervura central em esquerdo distal (ED, esquerdo proximal (EP, direito proximal (DP e direito distal (DD. As ninfas concentraram-se mais nos setores proximais da folha do meloeiro, quando comparados aos setores distais, nas três avaliações efetuadas no campo. Estes insetos preferem os setores proximais da folha por estarem mais próximos do floema, facilitando a obtenção do alimento. Do total de ninfas contadas nos setores das folhas do meloeiro, 13,08% foram encontradas no setor ED; 35,7% no setor EP; 36,7% no setor DP e 14,25% no setor DD. Portanto, recomenda-se efetuar a amostragem das ninfas próximo à nervura central da folha do meloeiro.The spatial nymphs distribution of Bemisia argentifolii Bellows & Perring (Hemiptera: Aleyrodidae among and within melon leaves was observed. The vertical distribution among leaves was done, selecting randomly leaves from node 5th through 20th. The counting of nymphs was performed on a weekly basis, at 49; 56 and 63 days after planting, using a circular leaf disc with an area

  7. Transmissão de begomovírus de plantas daninhas para tomateiros pela mosca-branca Begomovirus transmission from weeds to tomato by the whitefly

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    A.K.F. Silva

    2010-01-01

    Full Text Available Dentre numerosas enfermidades do tomateiro (Lycopersicon esculentum, destacam-se as viroses causadas por begomovírus, os quais são transmitidos pelo vetor Bemisia tabaci biótipo B. Na Chapada da Ibiapaba-CE, os begomovírus têm sido encontrados em várias áreas onde o tomateiro é cultivado, causando sérios danos à produção. Este trabalho teve por objetivos investigar a transmissão de begomovírus a partir de tomateiros infectados para plantas daninhas e verificar seu retorno das plantas daninhas para o tomateiro. Mudas sadias de tomateiro 'Santa Clara' e das plantas daninhas bredo-de-espinho (Amaranthus spinosus, caruru-de-mancha (Amaranthus viridis, mentrasto (Ageratum conyzoides e picão-preto (Bidens pilosa foram submetidas à inoculação por dois métodos: com o inseto vetor e por enxertia. Após 15 dias, realizou-se a extração do DNA de amostras foliares dos tomateiros e das espécies daninhas inoculadas. A PCR realizada com oligonucleotídeos degenerados e específicos para begomovírus revelou que na transmissão com o vetor as quatro espécies de plantas daninhas foram infectadas com o begomovírus do tomateiro, enquanto que, por enxertia, apenas o picão-preto foi infectado. O retorno do vírus das plantas daninhas para o tomateiro foi também observado nos dois casos. Percentuais de 70, 50, 20 e 12,5% de transmissão para os tomateiros ocorreram quando o vetor adquiriu o vírus em mentrasto, bredo-de-espinho, picão-preto e caruru-de-mancha, respectivamente. Na enxertia, a transmissão viral para os tomateiros ocorreu apenas quando se empregaram seções de bredo-de-espinho e de picão-preto infectados. As espécies daninhas investigadas demonstraram ser hospedeiras alternativas do begomovírus de tomate da região e, em condiçõs de campo e na presença do vetor, podem constituir importantes fontes do begomovírus para a hortaliça.The viruses caused by begomovirus are considered the most important virus diseases

  8. EFICIÊNCIA DO CONTROLE QUÍMICO SOBRE A MOSCA BRANCA Bemisia tabaci biótipo B (HEMIPTERA: ALEYRODIDAE EM MELOEIRO

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    Antônio Lindemberg Martins Mesquita

    2007-01-01

    efficient to control eggs, nymphs and adults of the whitefly, while the insect growth regulators buprofezin and pyriproxyfen did not control eggs and adults, but they controled nymphs, being pyriproxyfen more efficient than buprofezin.

  9. Compatibilidad de Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) y Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), importantes enemigos naturales de la mosca blanca Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) en cultivos hortícolas, con nuevas barreras físicas selectivas y modernos plaguicidas

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    Fernández Gallego, María del Mar

    2016-01-01

    Los programas de Gestión Integrada de Plagas (GIP) promueven el uso de estrategias de control que sean respetuosas con el medio ambiente, sin embargo el uso de insecticidas en los cultivos hortícolas sigue siendo necesario para el control de determinadas plagas, como es el caso de la mosca blanca Bemisia tabaci (Gennadius). Por ello, el objetivo de esta tesis es el estudio de la integración de las tres estrategias de control más empleadas hoy en día para el control de plagas: el control bioló...

  10. Domesticando moscas

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    Santiago Londoño Vélez

    2001-01-01

    Full Text Available Moscas de todos los colores. Historia del barrio Guayaquil. de Medellín, 1894-1934. Jorge Mario Betancur Gómez. Premios Nacionales de Cultura 1998, Ministerio de Cultura, Bogotá, 2000, 482 págs, il.

  11. Mortality of Bemisia tabaci biotype B (sternorrhyncha: aleyrodidae adults by aliphatic and aromatic synthetic sucrose esters

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    Mariangela Alves

    2008-12-01

    Full Text Available The B-strain of Bemisia tabaci Gennadius is a key pest of several crops and chemical control is the main control method used by growers, although reduction in efficacy due to insecticide resistance has already been reported. The aim of this work was to investigate the insecticidal effect of an array of synthetic sucrose esters with the aliphatic and aromatic groups on whitefly adults. Sucrose butyrate, caprate, octanoate, palmitate, oleate, octaacetate, phthalate, benzoate, and sucrose diacetate hexaisobutyrate were tested. The solutions were prepared and applied on the adults caught on yellow sticky traps using the Potter spray tower. Long-chains sucrose aliphatic esters were more effective against the silverleaf whiteflies and the highest mortality was obtained with sucrose oleate and sucrose octanoate. Since these compounds were tensoactive, sodium dodecylsulphate was also tested for the comparison but no effect was observed. Sucrose butyrate and other aliphatic and aromatic sucrose polyesters showed negligible effect on the silverleaf whiteflies.O biótipo B de B. tabaci Gennadius tem se destacado como uma praga-chave de diversas culturas. O controle químico tem sido a principal tática de controle utilizada, embora já se tenha observado redução na eficiência dos produtos devido ao desenvolvimento de resistência. Assim, o objetivo do presente trabalho foi avaliar o efeito de diversos ésteres de sacarose com grupos alifáticos ou aromáticos sobre adultos de mosca-branca. Butirato de sacarose, caprato, octanoato, palmitato, oleato, actaacetato, ftlato, benzoato e diacetato hexaisobutirato de sacarose foram testados. Soluções de éster de sacarose foram preparadas e aplicadas sobre adultos capturados em armadilhas adesivas utilizando Torre de Potter. Ésteres alifáticos de sacarose com longas cadeias foram mais efetivos contra mosca-branca e as maiores taxas de mortalidade foram obtidas com oleato e octanoato de sacarose. Uma vez que

  12. Resistência de meloeiro a Bemisia Tabaci biótipo B Resistance of melon to Bemisia Tabaci biotype B

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    Sérgio Alexandre Mottola Pereira Coelho

    2009-01-01

    Full Text Available Em âmbito mundial, a mosca-branca Bemisia tabaci (Genn. biótipo B é praga-chave em diversas culturas. O uso de resistência varietal se destaca entre os métodos de controle, sendo considerado o método ideal. O objetivo do presente trabalho foi avaliar, em casa de vegetação, a resistência de 32 cultivares de meloeiro em relação a essa mosca-branca. Para atratividade, em 'Neve' observou-se o menor número de adultos na face abaxial das folhas (0,6 adulto/10 cm², enquanto 'Nilo' foi a mais preferida (5,6 adultos/10 cm². A oviposição foi avaliada em testes com e sem chance de escolha; em ambos, 'Neve' proporcionou o menor número de ovos, contrastando com 'Nilo', a cultivar com a maior média. A colonização da mosca-branca durante o ciclo das plantas foi avaliada por meio de uma escala de notas variando de 0 (ausência de colonização até 6 (folha totalmente colonizada; 'Neve' destacou-se por sua reduzida colonização, sendo as mais altas médias obtidas em 'Imperial', 'Jangada', 'Vereda', 'Deneb' e 'Nilo'. Na duração do ciclo ovo-adulto da mosca-branca, que variou de 24,0 ('Neve' a 25,4 dias ('Jangada', as cultivares não diferiram entre si. Quanto à emergência de adultos, as menores médias foram induzidas por Vereda' (68,2% e 'Nilo' (69,3%, indicando a possível ocorrência de resistência do tipo antibiose nessas duas cultivares, enquanto as maiores médias ocorreram em 'Imperial' (90,9 % e 'Deneb' (89,6%. Considerando-se os parâmetros avaliados, infere-se que 'Neve' é a cultivar mais resistente a B. tabaci biótipo B, podendo ser indicada para plantio em regiões onde essa praga ocorra de forma acentuada ou para uso em programas de melhoramento.Silverleaf whitefly B. tabaci biotype B is an important worldwide pest of many crops. Use of resistant cultivars is considered the ideal method of control. In this research, 32 cultivars of melon were evaluated under greenhouse conditions reganding resistance to silverleaf

  13. Preferência de Bemisia tabaci biótipo B em linhagens mutantes de algodoeiro Bemisia tabaci biotype B preference in mutant cotton lines

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    Francisco das Chagas Vidal Neto

    2008-02-01

    Full Text Available Os efeitos de caracteres mutantes morfológicos do algodoeiro (Gossypium hirsutum L. r. latifolium Hutch.: folha okra, bráctea frego e planta vermelha, em relação à resistência à mosca-branca (Bemisia tabaci biótipo B Hemiptera: Aleyrodidae, foram avaliados em experimentos com ou sem chance de escolha. Os experimentos foram conduzidos em casa-de-vegetação, no delineamento de blocos ao acaso, em fatorial 23 + 1, com quatro repetições. O mutante com a característica planta vermelha foi menos atrativo e menos preferido para oviposição, em relação à planta verde, em ambos os ensaios, com ou sem escolha. Não houve preferência quanto à forma da folha e ao tipo de bráctea.The effects of cotton lines (Gossypium hirsutum L. r. latifolium Hutch. with mutants morphologic characteristics: okra leaf, frego bract and red plant in relation to host plant resistance to whitefly (Bemisia tabaci bioyipe B Hemiptera: Aleyrodidae, were evaluated in choice or no choice assays. The assays were carried out in the greenhouse conditions, according to a completely randomized block design, in a 23 + 1 in a factorial arrangement with four replications. The mutant with red plant characteristic was less attractive and less preferred for oviposition than the normal green plant does, in both, whit or without choice tests. It did not have preference in relation to the form of the leaf and bract type.

  14. Effects of double-stranded RNA on virulence of Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes against the silverleaf whitefly, Bemisia tabaci strain B (Homoptera: Aleyrodidae

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    Andréia Cristiane Souza Azevedo

    2000-03-01

    Full Text Available Bands of double-stranded RNA (dsRNA were detected in three out of twelve isolates of Paecilomyces fumosoroseus. Identity of these bands was confirmed by RNAse, DNAse and S1 nuclease treatments. The cure of dsRNA for one isolate (P92 was successfully carried out for a single conidium subculture. Isogenic strains, with or without dsRNA, were submitted to virulence tests against the whitefly Bemisia tabaci strain B. In contrast to findings for some phytopathogenic fungi, these dsRNA fragments did not cause hypovirulence in P. fumosoroseus.Bandas de dsRNA foram detectadas em três dos doze isolados de Paecilomyces fumosoroseus. A identidade destas bandas foi provada através de tratamentos com RNAse, DNAse e S1 nuclease. A cura do dsRNA para um dos isolados (P92 foi obtida através do isolamento de colônias monospóricas. Linhagens isogênicas, com e sem dsRNA, foram submetidas ao teste de virulência contra a mosca branca Bemisia tabaci biotipo B. Ao contrário do que ocorre para vários fungos fitopatogênicos, os fragmentos de dsRNA não causaram hipovirulência em P. fumosoroseus.

  15. Parâmetros biológicos de Bemisia Tabaci (genn. biótipo B (hemiptera: aleyrodidae em genótipos de algodoeiro Biological parameters of Bemisia Tabaci B biotype on cotton genotypes

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    Zeneide Ribeiro Campos

    2009-01-01

    Full Text Available A mosca-branca Bemisia tabaci biótipo B é uma praga de grande importância econômica para muitas culturas em todo o mundo. No Brasil, especialmente no Estado da Bahia, essa praga causou perdas que variam entre 30% e 70% em cultura de algodão. Essa pesquisa foi desenvolvida com o objetivo de avaliar parâmetros biológicos de B. tabaci biótipo B em genótipos de algodoeiro para verificar a possível ocorrência de antibiose como mecanismo de resistência sob condições de casa de vegetação. Os genótipos estudados foram IAC-23, Coodetec 406, BRS Aroeira, Fabrika, Coodetec 407, IAC-24, Makina, IAC 20-233, Coodetec 401 e CNPA Acala I. Foram avaliados os períodos de incubação e ninfal, o desenvolvimento total e a longevidade. Dos genótipos avaliados observou-se em Coodetec 406 maior período ninfal (14,7 dias e IAC-23 a menor viabilidade de ninfas (30,7%, indicando a ocorrência de resistência do tipo antibiose contra essa mosca-branca.The silverleaf whitefly Bemisia tabaci B biotype is an important pest of many crops throughout the world. In Brazil, specifically in the Bahia State, this insect caused losses estimated to 30-70% on cotton crops. The purpose of this research was to investigate biological parameters of the silverleaf whitefly biotype B in genotype of cotton bush to verify a possible occurrence of antibiosis as resistance mechanism cotton, under greenhouse conditions. The duration of the egg and nymphal stages, and the adult longevity of B. tabaci biotype B were evaluated in the genotypes IAC-23, Coodetec 406, BRS Aroeira, Fabrika, Coodetec 407, IAC-24, Makina, IAC 20-233, Coodetec 401 and CNPA Acala I. Among those evaluated genotypes, Coodetec 406 increased the nymph stage (14.7 days and IAC-23 reduced the nymphal viability (30.7%, suggesting the occurrence of antibiosis against this whitefly.

  16. Controle químico de ovos e ninfas de Bemisia tabaci biótipo B (Hemiptera: aleyrodidae Chemical control of Bemisia tabaci B biotype (Hemiptera: aleyrodidae eggs and nymphs

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    Giuliana Etore do Valle

    2002-06-01

    Full Text Available Moscas brancas são pragas de diversas culturas, causam redução na produção e na qualidade do produto. Inseticidas, com diferentes modos de ação vêm sendo utilizados, sem muito sucesso. Neste trabalho avaliou-se a eficiência de inseticidas sobre ovos de diferentes idades (1, 3 e 5 dias e de ninfas de 1° ínstar da mosca branca Bemisia tabaci biótipo B. Os experimentos foram realizados em condições de laboratório, sob temperatura de 25 ± 2°C e fotofase de 12 horas. Piriproxifem (75 mg L-1 atuou como excelente ovicida, sendo altamente eficiente, 3 dias de idade. Cartape (500 mg L-1 não teve efeito satisfatório, mas a 1000 mg L-1 foi eficiente em ovos com até 5 dias de idade. Quanto à ação sobre ninfas de 1° ínstar, para pulverizações na face superior das folhas, piriproxifem, a 75 mg L-1, apresentou eficiência na supressão da emergência de adultos, caracterizando presença de ação translaminar; buprofezim, cartape, acefato e fempiroximate não apresentaram eficiência no controle de ninfas. Quando aplicado na face inferior das folhas, buprofezim (375 mg L-1 apresentou eficiência comparável à de piriproxifem, impedindo a emergência de adultos.Whiteflies are pests of many crops, cause severe yield losses and reduce crop quality. Insecticides of different modes of action have been used without success. In this work, the efficiency of five insecticides on Bemisia tabaci B biotype (= B. argentifolii eggs and nymphs was evaluated under laboratory conditions (T = 25 ± 2°C; 12 h photophase. In relation to the ovicidal effect, pyriproxyfen (75 mg L-1 caused egg hatching inhibition up to three day old eggs. Cartap showed efficiency only at the concentration of 1000 mg L-1, supressing the viability of eggs up to five days. Soybean leaves with first instar nymphs were treated in the upper surface with pyriproxyfen (75 mg L-1, buprofezin (375 mg L-1, cartap (1000 mg L-1, acephate (750 mg L-1 and fenpyroximate (100 mg L-1; in

  17. Dinâmica populacional de Bemisia tabaci biótipo B em tomate monocultivo e consorciado com coentro sob cultivo orgânico e convencional Population dynamic of Benisua tabaci B biotype in monoculture tomato crop and consortium with coriander in organic and conventional crop system

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    Pedro HB Togni

    2009-06-01

    Full Text Available A mosca-branca Bemisia tabaci Biótipo B (Hemiptera: Aleyrodidae, é um herbívoro de difícil controle devido à alta plasticidade genotípica da espécie. No tomateiro pode causar danos severos principalmente pela transmissão de diversas viroses. O manejo do sistema de produção e o consórcio de culturas podem ter um efeito direto nas populações desse herbívoro, sem que seja necessária a aplicação de inseticidas. Avaliou-se a influência dos sistemas de produção orgânico e convencional e o consórcio tomate-coentro na dinâmica populacional da mosca-branca no campo experimental da Embrapa Hortaliças, de maio a setembro/06. O monitoramento dos adultos da mosca-branca e de seus inimigos naturais foi realizado utilizando-se armadilhas adesivas amarelas fixadas nas bordas e no interior das parcelas experimentais e a amostragem de ninfas foi realizada por observação direta das folhas de tomate no campo. Embora as populações ao redor dos diferentes tratamentos fossem equivalentes, a abundância de adultos de mosca-branca foi significativamente menor nas parcelas de tomate consorciado com coentro, tanto no sistema convencional como orgânico. Apenas o consórcio tomatecoentro em sistema orgânico apresentou redução significativa na quantidade de ninfas por planta em relação aos demais tratamentos. Os inimigos naturais foram significativamente mais abundantes em sistema orgânico e foi verificada uma correlação negativa da abundância dos inimigos naturais e a quantidade de ninfas por planta. A associação tomate-coentro e o manejo orgânico do agroecossistema favoreceram ao controle biológico natural da mosca-branca.Due to its high genotypic plasticity, the control of the silverleaf whitefly Bemisia tabaci B biotype (Hemiptera: Aleyrodidae, is difficult. This insect may cause severe damage to the tomato crop as a vector of several viruses. The management of the production system and the consortium with other crops may have a

  18. Resistance of tomato genotypes to the silverleaf whitefly mediated by acylsugars Resistência de genótipos de tomateiro a Bemisia tabaci biótipo B, mediada por acilaçúcares

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    Juliano TV de Resende

    2009-09-01

    Full Text Available Acylsugars in the leaflets of the wild accession LA-716 (Lycopersicon pennellii gives resistance to Bemisia spp., which causes expressive losses to the tomato crop. The goal of this work was to evaluate the resistance to the silverleaf whitefly (Bemisia tabaci biotype B of previously selected genotypes, based on the level of acylsugars in the leaflets. F2BC1 plants {F2[Lycopersicon esculentum TOM 584 x (L. esculentum TOM 584 x L. pennellii LA-716]} were selected for extreme contents of acylsugars: BPX-370B pl#30-275, BPX-370B pl#79-278, BPX-370B pl#30-380, BPX-370B pl#25-271 (high contents, BPX-370B pl#30-02, BPX-370B pl#30-142 (low contents. These genotypes, along with the parents TOM 584 and LA-716, were submitted to a silverleaf whitefly infestation. Oviposition and nymph development were evaluated. The oviposition on the genotypes BPX-370B pl#30-275 and BPX-370B pl#30-380 was significantly lower to that which occurred on the genotype TOM 584 and in the other genotypes of the F2RC1 generation. The four genotypes selected for high acylsugar contents presented the lowest number of nymphs, except to LA-716. Although the number of eggs in the BPX-370B pl#25-271 and BPX-370B pl#79-278 genotypes (high contents was elevated, the number of nymphs was reduced, similarly to the other high-acylsugar genotypes, probably due to antibioses effect.Acilaçúcares presentes nos folíolos do acesso selvagem 'LA-716' (Lycopersicon pennellii conferem resistência a moscas-brancas (Bemisia spp., causadoras de danos expressivos à cultura do tomate. O objetivo do trabalho foi avaliar a resistência de genótipos de tomateiro à mosca-branca Bemisia tabaci biótipo B, com base nos teores de acilaçúcares nos folíolos. Foram selecionadas plantas F2RC1{[L. esculentum 'TOM-584' x (L. esculentum 'TOM-584' x L. pennellii 'LA-716']} para teores extremos de acilaçúcares: BPX-370B pl#30-275, BPX-370B pl#79-278, BPX-370B pl#30-380, BPX-370B pl#25-271 (altos teores, BPX

  19. Efeito de fontes de potássio na infestação de Bemisia tabaci biótipo B e nas características de frutos de tomateiro sob ambiente protegido

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    Feltrin Deise Maria

    2002-01-01

    Full Text Available Bemisia tabaci (Gennadius biótipo B é considerada a espécie de mosca- branca mais nociva à agricultura, pois é responsável por grandes perdas de comercialização e por baixos preços no mercado, principalmente na cultura do tomateiro. Dentre os fatores ambientais, a nutrição mineral pode influenciar a manifestação de resistência da planta em relação ao inseto. Objetivou-se avaliar a influência de diferentes fontes de potássio no tomateiro sobre a infestação de mosca-branca e as principais características dos frutos. O experimento foi realizado no Núcleo Experimental de Campinas (IAC, de dezembro de 1999 a maio de 2000. O híbrido Rocio foi cultivado em "slabs" contendo substrato agrícola, em condições de ambiente protegido. Foram utilizadas quatro soluções nutritivas com variação nas fontes de potássio: KCl + K2SO4 + K2SiO3; KCl + K2SO4; K2SO4 e KCl. Realizaram-se três avaliações do número de ovos + ninfas aos 15, 30 e 45 dias após a infestação com adultos de mosca-branca. Avaliaram-se, ainda, a produtividade e a qualidade dos frutos. Observa-se que as soluções nutritivas com base nas diferentes fontes de potássio não influenciaram a infestação de B. tabaci biótipo B; não se verificou diferença entre os tratamentos em relação à qualidade dos frutos e à produtividade para o híbrido Rocio, em condições de ambiente protegido.

  20. Biology of Bemisia tabaci (Genn. B-biotype and parasitism by Encarsia formosa (Gahan on collard, soybean and tomato plants Aspectos biológicos de Bemisia tabaci (Genn. biótipo B e parasitismo por Encarsia formosa (Gahan em couve, soja e tomateiro

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    Karina Manami Takahashi

    2008-12-01

    Full Text Available The silverleaf whitefly Bemisia tabaci (Genn. B-biotype (= B. argentifolii (Hemiptera: Aleyrodidae is a polyphagous insect attacking many plant species of economic importance. A comparison study was conducted on the duration of the egg-to-adult period, and the percentage of hatching eggs of Bemisia tabaci (Genn. B-biotype on collard (Brassica oleracea L. var. acephala D.C., soybean(Glycine max (L. Merr. and tomato (Lycopersicon esculentum Mill. plants, as well as the egg-to-adult period of Encarsia formosa (Gahan on the 1st, 2nd, 3rd and 4th whitefly nymphal instars on these three plant species. The experiments were conducted in a laboratory (25ºC, 70 ± 10% RH, 14-hour photophase. The duration of the egg-to-adult period of B. tabaci was 19.8 days on collard, 21.2 days on soybean and 22.0 days on tomato. The number of hatched eggs was higher on collard when compared to soybean and tomato plants. Concerning E. formosa regardless of plant species, the duration for the egg-to-adult period was shorter for the 3rd and 4th instar nymphs as compared with the other instars.A mosca branca Bemisia tabaci (Genn. biótipo B é uma praga polífaga que ataca muitas culturas de importância econômica. O controle químico pode causar problemas como o aparecimento de resistência nesse inseto, resíduos nos produtos das culturas, ou mesmo poluição ambiental. Um método alternativo seria o controle biológico, com o parasitóide Encarsia formosa (Gahan, o mais usado contra moscas brancas a nível mundial. Avaliaram-se o tempo de desenvolvimento de ovo a adulto e a porcentagem de ninfas eclodidas de B. tabaci (Genn. biótipo B em couve (Brassica oleracea L. var. acephala D.C., soja (Glycine max (L. Merr. e tomateiro (Lycopersicon esculentum Mill., bem como o desenvolvimento de ovo a adulto de E. formosa em ninfas de 1º, 2º, 3º e 4º ínstares dessa mosca-branca nessas três espécies vegetais. Os experimentos foram desenvolvidos em laboratório, a 25ºC, 70

  1. Surtos populacionais de Bemisia tabaci no estado de São Paulo Outbreaks of Bemisia tabaci in the São Paulo State, Brazil

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    André Luiz Lourenção

    1994-01-01

    Full Text Available A partir de 1991, tem sido observada a presença da mosca-branca Bemisia tabaci (Genn. (Homoptera: Aleyrodidae em altas populações em hortaliças e orna-mentais nos municípios paulistas de Paulínia, Holambra, Jaguariúna e Artur Nogueira. Foram constatadas infestações severas em tomateiro, brócolos, berinjela e aboboreira; nesta última, o sintoma observado em plantas infestadas pela mosca-branca é o prateamento da face superior das folhas, em conjunto com queda drástica da produção. Uma lavoura de tomate severamente infestada por B. tabaci apresentava o sintoma referido colo amadurecimento irregular dos frutos do tomateiro; plantas invasoras presentes nessa área também foram intensamente colonizadas, principalmente Sida rhombifolia L., Sonchus oleraceus L., Solanum viarum Dun. e Ipomoea acuminata Roem. & Schult. Em Holambra, verificaram-se ataques intensos em plantas ornamentais, principalmente crisântemo (Chrysantemum morifolium Ramat. e bico-de-papagaio (Euphorbia pulcherrima Willd.; roseiras foral pouco colonizadas. Nessas hortaliças e nas ornamentais, a aplicação quase diária de inseticidas não reduziu a infestação do inseto. Além dessas plantas, campos de algodão, em Holambra, e de feijão, em Paulínia, também foram infestados por B. tabaci. Nos E.U.A., a capacidade de certas populações de B. tabaci de induzir o prateamento da folha em aboboreira e de colonizar intensamente E. pulcherrima, entre outros fatores, têm levado à distinção do biótipo "B" ou "poinsétia", nome vulgar dessa euforbiácea; todavia, estudos recentes na Califórnia (E.U.A. mostram a possibilidade de se tratar de duas espécies distintas. Dada a similaridade entre as infestações associadas a B. tabaci que vêm ocorrendo naquele país e, mais recentemente, no Brasil, é provável que o biótipo B ou essa nova espécie tenha sido aqui introduzido.Since 1991, an increase in the populations of the whitefly Bemisia tabaci (Genn. (Homoptera

  2. Effects of insecticides used in Bemisia tabaci (Gennadius biotype B control and their selectivity to natural enemies in soybean cropEfeitos dos inseticidas utilizados no controle de Bemisia tabaci (Gennadius biótipo B e sua seletividade aos inimigos naturais na cultura da soja

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    Simone Silva Vieira

    2012-10-01

    Full Text Available In recent crop seasons, the whitefly, Bemisia tabaci biotype B has become a serious pest in soybean crops due to high infestations and its control difficulties. Therefore, it is important to search control alternatives in the integrated pest management approach. Thus, it was evaluated in this study the efficacy of the whitefly control using different insecticides in greenhouse conditions and their selectivity to the parasitoids Encarsia formosa, Trichogramma pretiosum and Telenomus remus. Buprofezin 150 g. a.i.ha-1 + mineral oil 0.2% v/v and pyriproxyfen 100 g. a.i.ha-1 were considered the best options for the whitefly management due to combine good pest control efficacy with higher selectivity to the parasitoids except Encarsia formosa for which no treatment was classified as harmless. Betacyflutrin 9.375 + imidacloprid 75 g. i.a. ha-1 was efficient on controlling whiteflies nymphs but was not harmless to the studied natural enemies. In general, the treatments including pyretroids compounds (betacyflutrin 9.375 + imidacloprid 75 + spiromesifen 60, betacyflutrin 9.375 + imidacloprid 75 and lambda-cyhalothrin 26.5 + thiametoxan 35.25 g. a.i. ha-1 were the most harmful to the evaluated parasitoids and therefore it use should be avoid whenever possible. Nas últimas safras a mosca-branca, Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae tornou-se praga de importância econômica para a cultura da soja devido à ocorrência de altas infestações e à dificuldade de controle desta praga. Sendo assim, é importante buscar alternativas de manejo com base em um programa de manejo integrado de pragas. Assim, avaliaram-se neste trabalho a eficiência de diferentes inseticidas no controle da mosca-branca em casa-de-vegetação e a seletividade destes aos parasitoides Encarsia formosa, Trichogramma pretiosum e Telenomus remus. Buprofezina 150 g i.a. ha-1 + óleo mineral 0,2% v/v e piriproxifem 100 g. i.a. ha-1 foram consideradas as melhores opções para

  3. Resistência de genótipos de feijoeiro a Bemisia tabaci biótipo B Resistance of bean genotypes to Bemisia tabaci biotype B

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    Lucas Castro Torres

    2012-01-01

    Full Text Available O estudo de genótipos de feijoeiro resistentes à mosca-branca Bemisia tabaci (Genn. biótipo B (Hemiptera: Aleyrodidae é de grande importância devido aos danos ocasionados por essa praga à cultura. Neste trabalho, foram estudados a atratividade para adultos, a preferência para oviposição em testes com e sem chance de escolha, o ciclo ovo-adulto e o tipo e número de tricomas presentes nos folíolos. Os experimentos foram realizados em casa de vegetação avaliando-se, inicialmente, cem genótipos de feijoeiro. A resistência do tipo não-preferência para alimentação e/ou antibiose foi observada nos genótipos ARC-3, IAC-Alvorada e Canário 101, sendo a emergência de adultos fortemente influenciada pelos genótipos. Também se observou correlação negativa moderada entre o número de ovos e o número de tricomas glandulares, e correlação positiva muito forte entre o número de ovos e o número de tricomas tectores unciformes.The study of bean genotypes resistant to the whitefly Bemisia tabaci (Genn. B biotype (Hemiptera: Aleyrodidae has been of great importance due to the damage caused by this pest. In this research, bean genotypes were evaluated regarding attractiveness to whitefly adults, the preference for oviposition in free-choice and non choice tests, egg-to-adult development time and characterized for the presence, type and number of trichomes. The experiments were carried out under greenhouse conditions initially evaluating 100 bean genotypes. The non-preference type of resistance for feeding and/or antibiosis was observed in the genotypes ARC-3, IAC-Alvorada and Canário 101, and the emergence of adults was strongly influenced by the genotypes. It was also observed a moderate negative correlation between the number of eggs and the number of glandular trichomes, as well as a very strong positive correlation between the number of eggs and the number of unciform non-glandular trichomes.

  4. Plano de amostragem do biótipo B de Bemisia tabaci na cultura do pepino

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    Moura Marcelo Fialho de

    2003-01-01

    Full Text Available A adoção de programas de manejo integrado de pragas permite reduzir a aplicação de inseticidas e os planos convencionais de amostragem representam o ponto inicial na geração desses programas. Assim, o objetivo deste trabalho foi determinar plano de amostragem convencional para o biótipo B da mosca-branca Bemisia tabaci Genn. (Hemiptera: Aleyrodidae na cultura do pepino. Foram avaliadas as densidades de ninfas e de adultos em dez lavouras comerciais de pepino, Tocantins, MG, estudando nove sistemas amostrais formados pela combinação de três técnicas (batida de folha em bandeja de plástico branco, contagem direta dos insetos na face inferior da folha e coleta de folha em sacola de plástico e três unidades amostrais (folha do terço apical, mediano ou basal do espaldeiramento. A contagem direta em folha do terço basal foi o sistema com maior precisão econômica na amostragem de ninfas, mas não possibilitou a geração de plano de amostragem praticável. As batidas, em bandeja, de folha dos terços apicais, medianos ou basais do espaldeiramento foram os sistemas economicamente mais precisos na amostragem de adultos. Desses, apenas a batida de folha do terço mediano em bandeja gerou plano de amostragem praticável, sendo que este plano é composto de 196 amostras/lavoura.

  5. Interaction between resistant tomato genotypes and plant extracts on Bemisia tabaci (Genn. biotype B Interação de genótipos resistentes de tomateiro e extratos vegetais sobre Bemisia tabaci (Genn. biótipo B

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    Edson Luiz Lopes Baldin

    2007-10-01

    resistentes e extratos vegetais no controle de Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae biótipo B. Utilizaram-se os genótipos IAC-Santa Clara, PI-134417, LA-716, PI-134418 e PI-127826 e extratos aquosos à base de sementes de Azadirachta indica A. de Jussieu (Rutales: Meliaceae, ramos e folhas de Trichilia pallida Swartz (Rutales: Meliaceae. Em casa-de-vegetação, a pulverização com extratos de sementes de A. indica, folhas e ramos de T. pallida reduziu a atração da mosca-branca para o genótipo IAC-Santa Clara; em PI-134417, LA-716, PI-134418 e PI-127826, a presença dos extratos não afetou a atratividade a B. tabaci biótipo B. Extratos de sementes de A. indica e de folhas e ramos de T. pallida reduziram a oviposição em IAC-Santa Clara. O extrato de ramos de T. pallida reduziu a oviposição em PI-134417, PI-134418 e PI-127826; enquanto que o extrato de sementes de A. indica reduziu a oviposição em PI-127826. Já em LA-716, a presença dos extratos não afetou a oviposição. No laboratório, a presença dos extratos vegetais aumentou a mortalidade de ninfas nos genótipos. A interação genótipo x extrato foi significativa, indicando um efeito aditivo pelo uso de genótipos resistentes e extratos vegetais no controle da mosca-branca.

  6. Biology of Bemisia tabaci (Genn. B biotype (Hemiptera, Aleyrodidae on tomato genotypes Biologia de Bemisia tabaci (Genn. Biótipo B (Hemiptera, Aleyrodidae em genótipos de tomateiro

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    Maria Auxiliadora de Godoy Oriani

    2011-02-01

    Full Text Available Brazil is one of the main tomato (Solanum lycopersicum producers worldwide. Nevertheless, considerable part of the production is lost due to Bemisia tabaci (Genn. B biotype attacks. Resistant plants can be an important method for controlling this pest in an integrated pest management. Tests for evaluating some biological aspects of B. tabaci were carried out on 18 tomato genotypes, in controlled laboratory greenhouse conditions. Thirty-day-old plants placed in plastic cages were infested with 20 whitefly pairs each, for 24 h. The development of at least 30 eggs in three leaflets per plant (repetition was observed until adult emergence. The development period of insects grown in LA1335, PI365928 and LA722 genotypes took three days longer when compared to the ones grown in PI134418 (20.3 days. The highest mortality rate of whitefly nymphs occurred in PI365928, LA1335 and LA722 genotypes (63.8, 54.5 and 53.3%, respectively, and the smallest ones in IAC294 and IAC68F-22-2 genotypes (4.9 e 6.2%, respectively. LA1335, PI365928 and LA722 genotypes presented moderate feeding nonpreference and/or antibiosis-based resistance to B. tabaci B biotype.O Brasil é um dos maiores produtores mundiais de tomate (Solanum lycopersicum, porém grande parte da produção é perdida devido ao ataque de Bemisia tabaci (Genn. biótipo B. Entre as táticas de controle dessa praga num manejo integrado de pragas, pode-se relacionar a resistência de plantas. Ensaios para avaliar alguns aspectos biológicos de B. tabaci foram realizados com 18 genótipos de tomateiro, em condições controladas de laboratório (casa de vegetação. Plantas com 30 dias de idade foram colocadas em gaiolas plásticas e infestadas com 20 casais de moscas-brancas cada, durante 24h. Acompanhou-se então o desenvolvimento de pelo menos 30 ovos em três folíolos por planta (repetição até a emergência dos insetos. Os insetos criados nos genótipos LA1335, PI365928 e LA722 apresentaram

  7. Effect of bean genotypes, insecticides, and natural products on the control of Bemisia tabaci (Gennadius biotype B (Hemiptera: Aleyrodidae and Caliothrips phaseoli (Hood (Thysanoptera: Thripidae = Efeito de genótipos de feijoeiro, inseticida e produtos naturais no controle Bemisia tabaci (Gennadius biotipo B (Hemiptera: Aleyrodidae e Caliothrips phaseoli (Hood (Thysanoptera: Thripidae

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    Júlio Cesar Janini

    2011-07-01

    ninfas de B. tabaci biótipo B e ninfas de C. phaseoli nos folíolos dos genótipos. Concluiu-se: o número de ovos e ninfas de B. tabaci biótipo B foi menor em IAC Centauro e maior em IAC Harmonia. Osgenótipos testados foram igualmente infestados por C. phaseoli. IAC Centauro e IAC Harmonia associado ao óleo de nim e com destaque a dose cheia (1,0%, propiciaram menor número de ovos de mosca branca e de ninfas tripes, e o último deles atuou reduzindo o número de ninfas de mosca branca. Nos genótipos testados o inseticida proporcionou redução no número de ovos e ninfas de mosca branca e de ninfas de tripes, com incremento na dose recomendada.

  8. Efeito de extratos aquosos de meliáceas sobre Bemisia tabaci biótipo B em tomateiro Effect of aqueous extracts of meliaceous plants on Bemisia tabaci B biotype on tomato plants

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    ANTONIO PANCRÁCIO DE SOUZA

    2000-01-01

    Full Text Available Comparou-se a bioatividade de extratos aquosos a 3% (p/v de três meliáceas, Melia azedarach L. (frutos verdes, Trichilia pallida Swartz (ramos e Azadirachta indica A. Juss (sementes, em relação à mosca branca Bemisia tabaci (Gennadius biótipo B, criada em tomateiro. No primeiro experimento os extratos foram aplicados sobre ovos e sobre ninfas com três dias de idade, avaliando-se a mortalidade e a duração das fases de ovo e de ninfa. No segundo experimento os extratos foram aplicados apenas sobre as ninfas, avaliando-se a mortalidade nessa fase e a longevidade e fecundidade dos adultos. Em relação à fase de ovo, o extrato de T. pallida foi o que provocou maior mortalidade, seguindo-se os de A. indica e M. azedarach. A maior mortalidade ninfal foi constatada com o extrato de A. indica, seguindo-se os de T. pallida e M. azedarach. Nenhum dos extratos afetou a duração das fases de ovo e de ninfa, assim como a longevidade e fecundidade.The objective of this research was to compare the effect of aqueous extracts of fresh fruits of Melia azedarach L., twigs of Trichilia pallida Swartz and seeds of zadirachta indica A. Juss, on eggs and nymphs of silverleaf whitefly Bemisia tabaci (Gennadius B biotype reared on tomato plants. The extracts were tested at a concentration of 3%. In the first experiment, the extracts were applied on eggs and 3-day-old nymphs. Records were taken on mortality, duration of egg and nymphal stages. In the second experiment the extracts were applied on 3-day-old nymphs and records were taken on nymphal mortality, adult longevity and fecundity. The extracts of T. pallida were the most effective on eggs, followed by A. indica and M. azedarach. The extracts of A. indica were the most effective on nymphs followed by T. pallida and M. azedarach. In both experiments, the duration of egg and nymph stages, longevity and fecundity were not affected by the extracts.

  9. Toxicidade do extrato aquoso das folhas de Anacardium humile para Bemisia tuberculata Toxicity of aqueous extract of Anacardium humile leaves on Bemisia tuberculata

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    Nézio Nery de Andrade Filho

    2010-08-01

    Full Text Available A mosca-branca Bemisia tuberculata (Bondar, 1923 (Hem.: Aleyrodidae é uma das principais pragas da cultura da mandioca no Estado do Mato Grosso do Sul; no entanto, não há produtos registrados para seu controle. Produtos vegetais podem constituir em alternativa viável de controle de insetos e, por sua fotodegradabilidade, diminuir os riscos ao ambiente e ao homem. Objetivou-se, por meio deste trabalho, avaliar o efeito do extrato aquoso do "cajuzinho-do-cerrado" Anacardium humile St Hill (Anacardeaceae, nas concentrações de 2,0; 0,8; 0,4 e 0,05%, sobre a biologia de B. tuberculata, bem como identificar a classe de metabólitos secundários presentes no referido extrato. O experimento foi conduzido em casa de vegetação, sob temperatura de 26±4°C. O extrato aquoso de A. humile causou aumento da duração da fase larval e mortalidade significativamente superior à testemunha em todas as concentrações testadas. Concluiu-se que o extrato aquoso de folhas de A. humile provoca mortalidade em ninfas de B. tuberculata e alongamento da fase das ninfas sobreviventes. O extrato aquoso de folhas de A. humile apresenta taninos, açúcares redutores e saponinas, e o seu índice de espuma (Índice Afrosimétrico é de 1250.The whitefly Bemisia tuberculata (Bondar, 1923 (Hem.: Aleyrodidae is the main pest of cassava crops in Mato Grosso do Sul state, however there are no products registered for its control. Plant products may represent a viable alternative for insect pest control and, due to their photo-degradability, they may reduce risks to the environment and to man. The aim of this study is to assess the effect of "cajuzinho-do-cerrado" Anacardium humile St Hill (Anacardeaceae aqueous leaf extract on the biology of B. tuberculata at the concentrations 2.0; 0.8; 0.4; 0.05%, as well as to identify the class of secondary metabolites present in the referred extract. The experiment was carried out in a greenhouse at a temperature of 26±4°C. The

  10. Only the B biotype of Bemisia tabaci is present on vegetables in São Paulo State, Brazil Somente o biótipo B de Bemisia tabaci ocorre em hortaliças no Estado de São Paulo, Brasil

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    Kelly Cristina Gonçales Rocha

    2011-02-01

    Full Text Available Bemisia tabaci (Genn. is one of the most important pests in cultivated areas of vegetables and ornamental crops around the world. Based on the mitochondrial cytochrome oxidize I (mtCOI sequence, there is evidence that B. tabaci should be considered a cryptic species complex of 11 groups containing 24 species. Two of the groups, Middle East-Asia Minor 1 and Mediterranean include biotypes B and Q, respectively. In this study we evaluated the mtCOI sequence of B. tabaci populations collected in sites of the state of São Paulo, Brazil. Using PCR-RFLP with Taq I, a typical biotype B profile was obtained for all specimens. Based on the comparison with mtCOI reference sequences we found four haplotypes all belonging to the Middle East-Asia Minor 1. They occurred in the hosts pepper (Capsicum annuum L., tomato (Solanum lycopersicum L., eggplant (Solanum melongena L. and cucurbitaceae plants.Bemisia tabaci (Genn. é considerada uma das mais importantes pragas em cultivos de hortaliças e ornamentais em todo o mundo. Baseado na análise da seqüência mitocondrial (citocromo oxidase I - mtCOI foi proposto recentemente que B. tabaci deva ser considerado um complexo críptico de espécies, contendo 11 grupos e 24 espécies. Dois destes grupos: Middle East-Asia Minor e Mediterranean englobam os biótipos B e Q, respectivamente. Avaliou-se a sequência mtCOI de espécimes de B. tabaci coletados em regiões do estado de São Paulo, Brasil. Por PCR-RFLP utilizando-se a enzima Taq I, pôde-se observar somente o padrão típico de clivagem para o biótipo B. Comparando-se com sequências consenso, todas as moscas brancas foram classificadas no grupo Middle East-Asia Minor e puderam ser separadas em quatro haplótipos, indicando prevalência do biótipo B em áreas de pimentão (Capsicum annuum L., tomate (Solanum lycopersicum L., cucurbitáceas e berinjela (Solanum melongena L. do Estado de São Paulo.

  11. Sella & Mosca Wine, Fashion Taste in China

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    Bai Yifeng; Sun Yongjian

    2006-01-01

    @@ Sella & Mosca Winery(Qingdao) Co., Ltd. is a subsidiary owned by Campari Group, one of the leading grape wine producers in Italy, with an investment of US$30 billion in Qingdao city in 1999. On the eve of China's traditional Mid-autumn Festival(October 6),China's Foreign Trade interviewed Carbriele Scapin,General Manager of Sella & Mosca Winery(Qingdao) Co., Ltd., he and his company were busy onthe mar keting job because the festival isa good day for the Chinese family reunite which cannot be lived through without drinking some grape wine.

  12. Repelência e deterrência na oviposição de Bemisia tabaci biótipo B pelo uso de extratos vegetais em Cucurbita pepo L Repellence and deterrence on oviposition of Bemisia tabaci biotype B by the use of vegetal extracts in Cucurbita pepo L

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    J.P.G.F. Silva

    2012-01-01

    Full Text Available Bemisia tabaci biótipo B é um dos principais insetos-praga na cultura da abobrinha (Cucurbita pepo L.. O manejo dessa mosca-branca tornou-se grande desafio aos agricultores, uma vez que esta apresenta rápida capacidade de desenvolver resistência a diferentes classes de inseticidas. Como alternativa vem sendo investigado o uso de extratos vegetais com atividades inseticida e/ou insetistática, os quais têm revelado resultados promissores no combate a inseto. O presente trabalho teve por objetivo avaliar os possíveis efeitos de sete extratos provenientes de cinco espécies vegetais, Ruta graveolens L. (folhas, Azadirachta indica A. Juss. (folhas + ramos, Trichilia pallida Swartz (ramos, T. pallida (folhas, A. indica (amêndoas, Chenopodium ambrosioides L. (inflorescências + ramos+ folhas e Mentha pulegium L. (folhas, sobre Bemisia tabaci biótipo B em abobrinha, por meio de testes de repelência e deterrência para oviposição. Em teste com chance de escolha, avaliou-se a atratividade e determinou-se o índice de repelência após 6, 24 e 48 horas da aplicação dos extratos. A oviposição foi verificada após a terceira contagem do número de adultos. O extrato à base de folhas de M. pulegium mostrou repelência e deterrência à oviposição de B. tabaci biótipo B, podendo ser recomendado como alternativa para o manejo do inseto.Bemisia tabaci biotype B is one of the main pests in squash (Cucurbita pepo L.. The management of this whitefly has become a major challenge to growers, since they have the ability to quickly develop resistance to different classes of insecticides. Alternatively, the use of plant extracts with insecticide and/or insectistatic activities has been investigated, showing promising results for the whitefly control. The present study evaluated the possible effects of seven extracts from five plant species, Ruta graveolens L. (leaves, Azadirachta indica A. Juss. (leaves + branches, Trichilia pallida Swartz (branches

  13. Efeito inseticida sistêmico de nanoformulações à base de nim sobre Bemisia tabaci (Hemiptera: Aleyrodidae biótipo B em tomateiro

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    Sheila Salles de Carvalho

    2015-01-01

    Full Text Available Este estudo avaliou a ação inseticida sistêmica e o efeito residual de nanoformulações à base de derivados de nim (Azadirachta indica A. Juss, Meliaceae sobre ninfas de Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae, espécie-praga de diversas culturas de importância econômica. Suspensões coloidais contendo nanocápsulas carregadas com produtos derivados de A. indica foram preparadas utilizando polímeros biodegradáveis como poli-ε-caprolactona (PCL e poli-β-hidroxibutirato (PHB. A matriz encapsulada era composta por uma formulação comercial contendo uma quantidade enriquecida e conhecida dos limonoides azadiractina e 3-tigloilazadiractol (Azamax® 1,2 CE. Inicialmente foi estimada a CL50, para ninfas de B. tabaci, de soluções contendo óleo de nim, que foram aplicadas via água de irrigação (solo em tomateiro. Posteriormente, dois lotes de nanoformulações, com variação no tipo e quantidade dos polímeros e na quantidade do óleo comercial, foram testados quanto à ação sistêmica. As nanoformulações NC L5-2 (com nanocápsulas de PCL e NC L6-1 (com nanocápsulas de PHB, as mais eficazes entre as testadas, foram avaliadas quanto ao efeito residual. A CL50 estimada foi de 180,67 mg L–1 de azadiractina. Constatou-se também que a ação sistêmica de óleos e nanoformulações contendo compostos de nim dependem das condições ambientais em que são aplicados. O Azamax® não apresenta efeito deterrente sobre a oviposição, nem age sobre o desenvolvimento embrionário da mosca-branca quando aplicado via água de irrigação no solo no momento da infestação. As nanoformulações selecionadas são bioativas mesmo cerca de 30 dias após a aplicação, não diferindo do produto comercial.

  14. Aspectos biológicos de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae alimentada com Bemisia tabaci (Gennadius, 1889 biótipo B (Hemiptera: Aleyrodidae criada em três hospedeiros Biological aspects of Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae fed on Bemisia tabaci (Gennadius, 1889 biotype B (Hemiptera: Aleyrodidae reared in three hosts

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    Cláudio Gonçalves Silva

    2004-04-01

    Full Text Available Estudaram-se alguns aspectos biológicos de adultos de Chrysoperla externa (Hagen oriundos de larvas alimentadas com ninfas da mosca-branca Bemisia tabaci (Gennadius biótipo B, criadas em folhas de pepino (Cucumis sativus var. caipira, couve (Brassica oleraceae var. acephala e na planta invasora leiteiro (Euphorbia heterophylla. Discos foliares dos hospedeiros contendo ninfas de terceiro e quarto estádios da mosca-branca foram acondicionados em placas de Petri contendo ágar-água a 1%. Em cada placa foi colocada uma larva de C. externa recém-eclodida, onde permaneceram até a emergência dos adultos. Foram avaliados o peso logo após a emergência, os períodos de pré-oviposição, oviposição, efetivo de oviposição, pós-oviposição, número total de ovos produzidos por fêmea e longevidade. Avaliaram-se, também, o período embrionário e a viabilidade dos ovos, coletando-se, uma vez por semana, uma amostra de 10% do total de ovos produzidos no dia, ao longo de todo o período reprodutivo. O peso de machos e fêmeas não diferiu significativamente em função do hospedeiro da presa, sendo em média de 4,7 mg. De maneira geral, adultos de C. externa oriundos de larvas alimentadas com ninfas de B. tabaci biótipo B criadas em leiteiro apresentaram performance inferior em relação àqueles oriundos do pepino e da couve. O período de oviposição foi, em média, de 49,5 dias para o pepino e a couve, e de 31,6 dias para o leiteiro. A produção de ovos foi reduzida em aproximadamente 50% em leiteiro, sendo de 293,8 ovos; no pepino e couve, a média foi de 591,3 ovos. Ninfas de B. tabaci biótipo B criadas em leiteiro causaram uma redução da viabilidade dos ovos de C. externa, que foi 62,8% e 57,7% inferior ao verificado para o pepino e a couve, respectivamente.The aim was to study some biological aspects of adults of Chrysoperla externa (Hagen, from larvae fed on nymphs of third and fourth stages of Bemisia tabaci (Gennadius biotype B

  15. Aqueous extracts and oil of neem combined with neonicotinoid insecticides against Bemisia tabaci biotype B in melon Extratos aquosos e óleo de nim associados com inseticidas neonicotinóides sobre Bemisia tabaci biótipo B em meloeiro

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    Maria Santana de Araújo Trindade

    2007-12-01

    Full Text Available This research was aimed at evaluating nymph population density of whitefly (Bemisia tabaci biotype B in melon plants after treatment with neem-dry-leaf aqueous extracts and neem-oil ( A. Juss. applied alternately with neonicotinoid insecticides under field conditions. The experimental design was a randomized block, with 6 treatments and 4 replications. The treatments were control (only water; neem-dry-leaf extract at 5% (neem-dry-leaf powder 50g L-1 of water; neem oil (5.0mL L-1 water; chemicals insecticides imidacloprid (30g 25L-1 of water and acetamiprid (5g 20L-1 of water; neem-dry-leaf extract at 5% weekly alternated with imidacloprid (30g 25L-1 of water and acetamiprid (5g 20L-1 of water; neem oil (5.0mL L-1 of water weekly alternated with imidacloprid (30g 25L-1 of water and acetamiprid (5g20 L-1 of water. The efficiency of treatments was compared through of the number of nymphs recorded in leaves of melon with 35, and 50 days after planting. The less number of nymphs was registered when the neem oil was applied alternatively with the chemical treatment with efficiency of 28.58 and 7.85% in the first and second evaluations, respectively. However, the nymphs incidence was higher when the neem oil and the chemical treatment were applied separately.O objetivo deste trabalho foi avaliar a densidade populacional de ninfas de mosca-branca (Bemisia tabaci biótipo B em plantas de melão após o tratamento com extratos aquosos de folhas secas de nim e de óleo de nim (Azadiracta indica A. Juss., aplicados alternadamente com inseticidas neonitotinóides, sob condições de campo. O delineamento utilizado foi o de blocos casualizados, com 6 tratamentos e 4 repetições. Foram utilizados os seguintes tratamentos: controle (apenas água; extrato aquoso de folhas secas de nim a 5% (pó de folhas secas de nim, 50 g L-1 de água; óleo de nim (5mL L-1 de água; inseticidas químicos imidacloprid (30g 25L-1 de água e acetamiprid (5g 20L-1 de

  16. Estudios sobre la transmisión por "moscas blancas" (Homoptera: aleyrodidae de virus asociados con el "cuero de sapo" en yuca (Manihot esculenta Crantz

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    Angel S. Juan C.

    1987-12-01

    Full Text Available Estudios realizados en la zona endémica al "cuero de sapo" (Quilcacé, Cauca, encaminados a determinar la presencia de vectores de la enfermedad mostraron la existencia de dos virus asociados con "moscas blancas". El primero denominado "agente mosaico" fue transmitido por Bemisia tuberculata, el segundo asintomático, por Aleurotrachelus socialis. El 3.3% de la población de B. tuberculata utilizada transmitió el "agente mosaico" al clón M Col 2063 (Secundina y no a M Col 113: el 2.4 % de A. socialis transmitió el asintomático al clón Secundina y el 4.7% a M Col 113. El "agente mosaico", no fue identificado, pero si se demostró que el asintomático presente era CsXV; este sería el primer registro de un potexvirus transmitido por "moscas blancas". El papel de los dos virus en la etiología del “cuero de sapo” continúa en estudio.Whiteflies collected from a frogskin infested field in Quilcacé (Cauca were caged individually on M Col 2063 (Secundina and M Col 113 plants. It was possible to identify the species (Aleurotrachelus socialis, Trialeurodes variabilis and Bemisia tuberculata from pupae present on over 50% of the plants. A. socialis was found most f frequently and B. tuberculata the least com mom of the species. A. socialis was associated with the transmission of both CsXV and a serologically related strain, identified on the basis of symptoms produced on Nicotiana bentamiana, B. tuberculata was associated with the transmission of a mosaic agent to Secundina. The identify of the mosaic agent is unknown.

  17. Infestação de Bemisia tabaci biótipo B e Caliothrips phaseoli em genótipos de feijoeiro Infestation of Bemisia tabaci biotype B and Caliothrips phaseoli on bean genotypes

    Directory of Open Access Journals (Sweden)

    Flávio Gonçalves de Jesus

    2010-01-01

    Full Text Available Avaliou-se o comportamento de genótipos de feijoeiro sob a infestação de Bemisia tabaci (Genn. biótipo B e Caliothrips phaseoli (Hood em condições de campo, nas épocas de cultivo "de inverno", "das águas" e "da seca". Adotou-se o delineamento de blocos casualizados em esquema de parcelas sub-subdividida (19x3x6, com 19 genótipos (IAC Tybatã, IAC Una, FT Nobre, Pérola, Gen 96A98-15-3-32-1, Gen 96A45-3-51-52-1, IAC Alvorada, IAC Diplomata, Gen 96A3-P1-1-1, LP 98-122, LP 02-130, LP 01-38, LP 9979, BRS-Pontal, BRS-Requinte, BRS-Triunfo, BRS-Grafite, CV-48 e Z-28, três épocas de cultivos (inverno, águas e seca e seis períodos de avaliação. As avaliações foram realizadas semanalmente, contando-se o número de ovos e ninfas de B. tabaci e ninfas de C. phaseoli em dez folíolos por parcela. Os genótipos IAC Una, Pérola, Gen 96A45-3-51-52-1, Gen 96A98-15-32-1, FT Nobre, IAC Tybatã, IAC Alvorada, LP 02-130, LP 01-38, LP 98-122, IAC Diplomata e Gen 96A3P1-1-1 foram menos ovipositados por B. tabaci no cultivo "das águas". Os genótipos Pérola, Gen 96A45-3-51-52-1, IAC Una, Gen 96A98-15-32-1, IAC Tybatã e FT Nobre foram menos infestados por C. phaseoli. A maior incidência de ninfas de mosca-branca ocorreu no fim de janeiro no cultivo "das águas" e início de maio no cultivo "da seca"; para tripés, foi em junho durante o cultivo "de inverno". A maior incidência da população de B. tabaci e C. phaseoli, ocorreu dos 46 aos 60 dias após a emergência das plantas.The response of bean genotypes to infestation of Bemisia tabaci (Genn. biotype B and Caliothrips phaseoli (Hood in field conditions on the winter, rainy and dry seasons was evaluated. The experiment was arranged in a randomized Sub-divided (19x3x6 blocks design with 19 genotypes (IAC Tybatã, IAC Una, FT Nobre, Pérola, Gen 96A98-15-3-32-1, Gen 96A45-3-51-52-1, IAC Alvorada, IAC Diplomata, Gen 96A3-P1-1-1, LP 98-122, LP 02-130, LP 01-38, LP 9979, BRS-Pontal, BRS

  18. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae) y su posible actividad adaptativa

    OpenAIRE

    Eneida Torres Cabra; Javier Hernández-Fernández

    2014-01-01

    La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae) es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realiz...

  19. Distribuição espacial de Aphis gossypii (Glover (Hemiptera, Aphididae e Bemisia tabaci (Gennadius biótipo B (Hemiptera, Aleyrodidae em algodoeiro Bt e não-Bt Spatial distribution of Aphis gossypii (Glover (Hemiptera, Aphididae and Bemisia tabaci (Gennadius biotype B (Hemiptera, Aleyrodidae on Bt and non-Bt cotton

    Directory of Open Access Journals (Sweden)

    Tatiana Rojas Rodrigues

    2010-03-01

    Full Text Available Distribuição espacial de Aphis gossypii (Glover (Hemiptera, Aphididae e Bemisia tabaci (Gennadius biótipo B (Hemiptera, Aleyrodidae em algodoeiro Bt e não-Bt. O estudo da distribuição espacial de adultos de Bemisia tabaci e de Aphis gossypii nas culturas do algodoeiro Bt e não-Bt é fundamental para a otimização de técnicas de amostragens, além de revelar diferenças de comportamento de espécies não-alvo dessa tecnologia Bt entre as duas cultivares. Nesse sentido, o experimento buscou investigar o padrão da distribuição espacial dessas espécies de insetos no algodoeiro convencional não-Bt e no cultivar Bt. As avaliações ocorreram em dois campos de 5.000 m² cada, nos quais se realizou 14 avaliações com contagem de adultos da mosca-branca e colônias de pulgões. Foram calculados os índices de agregação (razão variância/média, índice de Morisita e Expoente k da Distribuição Binomial Negativa e realizados os testes ajustes das classes numéricas de indivíduos encontradas e esperadas às distribuições teóricas de freqüência (Poisson, Binomial Negativa e Binomial Positiva. Todas as análises mostraram que, em ambas as cultivares, a distribuição espacial de B. tabaci ajustou-se a distribuição binomial negativa durante todo o período analisado, indicando que a cultivar transgênica não influenciou o padrão de distribuição agregada desse inseto. Já com relação às análises para A. gossypii, os índices de agregação apontaram distribuição agregada nas duas cultivares, mas as distribuições de freqüência permitiram concluir a ocorrência de distribuição agregada apenas no algodoeiro convencional, pois não houve nenhum ajuste para os dados na cultivar Bt. Isso indica que o algodão Bt alterou o padrão normal de dispersão dos pulgões no cultivo.The study of spatial distribution of the adults of Bemisia tabaci and the colonies of Aphis gossypii on Bt and non-Bt cotton crop is fundamental for

  20. Con larvas de moscas sanan heridas crónicas

    OpenAIRE

    Universidad del Rosario, Programa de Divulgación Científica

    2008-01-01

    Diminutas, blancas, silenciosas, similares a los ‘gusanos’ que se encuentran en una guayaba, son las larvas esterilizadas de una mosca verde conocida científicamente como Lucilia sericata, capaces de sanar las heridas de una vaca y varios conejos. Así lo pudieron constatar los miembros del grupo de investigación en terapia larval de la Facultad de Medicina de la Universidad del Rosario, dirigidos por el profesor Felio Bello, biólogo y Ph.D en Entomología. Aunque las investigaciones, exper...

  1. Nuevos registros de especies del género Eretmocerus (Hymenoptera: Aphelinidae, parasitoides de Trialeurodes vaporariorum y el complejo Bemisia tabaci (Hemiptera: Aleyrodidae en Argentina

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    Silvia N. LÓPEZ

    2008-01-01

    Full Text Available El objetivo de este trabajo es dar a conocer nuevos registros y distribuciones de las especies del género Eretmocerus Haldeman, parasitoides de las dos especies de mosca blanca que tienen mayor importancia económica en cultivos hortícolas y ornamentales en Argentina. Una especie de Eretmocerus Haldeman fue hallada parasitando a Trialeurodes vaporariorum (Westwood en Santa Fe y Buenos Aires; por sus caracteres morfológicos, se encuentra en el grupo californicus , cercana a corni Haldeman, podría tratarse de una nueva especie. Asimismo, se amplía la distribución geográfica de Eretmocerus mundus Mercet, enemigo natural del complejo Bemisia tabaci (Gennadius, a las provincias de San Juan y Buenos Aires.

  2. Enemigos naturales de la mosca blanca Aleurodicus dispersus Russell (Homoptera: Aleyrodidae): parasitoides y depredadores.

    OpenAIRE

    2016-01-01

    Se estudió la composición de parasitoides y depredadores de la mosca blanca en espiral Aleurodicus dispersus así como la abundancia relativa de las primeras diez fincas productoras de banano, durante 1997 y 1998 en Matina, Limón, Costa Rica. Se recuperaron cuatro especies de parasitoides de ninfas de mosca blanca Encarsiella noyesi Hayat, E. aleurodici (Girault), Encarsiella probo nsp. y Encarsia guadeloupae Viggiani. Los depredadores de ninfas y adultos de mosca blanca más comunes fueron dos...

  3. Gaetano Mosca — aktualność uwag o systemie demokracji przedstawicielskiej

    OpenAIRE

    Żyromski, Marek

    1991-01-01

    The purpose of the article is to turn the readers' attention to the threats and dangers of functioning of the democratic system. The starting point for the considerations is the conception of a famous Italian sociologist Gaetano Mosca (1858-1941), a co-author of the sociological theory of elites. Gaetano Mosca was opposed to the introduction of a general right to vote and was against granting the voting rights to women. Besides, he was a strong opponent of proportional electora...

  4. Assesing Bemisia tabaci (Genn. biotype B resistance in soybean genotypes: Antixenosis and antibiosis Evaluación de la resistencia de genotipos de soya a Bemisia tabaci (Genn. biotipo B: Antixenosis y antibiosis

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    José Paulo Gonçalves Franco da Silva

    2012-12-01

    Full Text Available Since it was first reported in Brazil in the 1990s, the B biotype of silverleaf whitefly (Bemisia tabaci Genn., Hemiptera: Aleyrodidae has been recognized as an important pest in soybeans (Glycine max L., reducing the productivity of this legume species in some areas of the country. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM. This study evaluated the performance of 10 soybean genotypes prior to whitefly infestation, by testing attractiveness and preference for oviposition in the greenhouse and antibiosis in the laboratory. In a multiple-choice test, 'IAC-17' was the least attractive to insects. In a no-choice test, 'IAC-17' was the least attractive for egg deposition, indicating the occurrence of non-preference for oviposition on this genotype. Trichome density was positively correlated with the oviposition site and may be associated with the resistance of 'IAC-17' to infestation. The genotypes 'IAC-PL1', 'IAC-19', 'Conquista', 'IAC-24' and 'IAC-17' extended the insect's life cycle, indicating the occurrence of a small degree of antibiosis and/or non-preference for feeding.Desde que se registró por primera vez en Brasil en la década de 1990, el biotipo B de la mosca-blanca (Bemisia tabaci Genn., Hemiptera: Aleyrodidae, se reconoce como una importante plaga de la soya (Glycine max L. y es lo que reduce la productividad de estas especies de leguminosas en algunas zonas del pais. Como una alternativa al control químico, el uso de genotipos resistentes representa una herramienta importante para la gestión integrada de plagas (MIP. Este trabajo evaluó el comportamiento de 10 genotipos de soya frente al ataque de la mosca-blanca, por medio de ensayos de atractividad y preferencia para ovipostura en invernaderos y antibiosis en laboratorio. En una prueba de elección multiple, 'IAC-17' fue el menos atractivo para los insectos. En una prueba sin elecci

  5. No-choice ovipositional nonpreference of Bemisia tabaci (Gennadius B biotype on tomato genotypes Não-preferência para oviposição de Bemisia tabaci (Gennadius biótipo B em genótipos de tomateiro em teste sem chance de escolha

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    Maria Auxiliadora de Godoy Oriani

    2011-04-01

    to a high density of type V nonglandular trichomes.O Brasil é um dos maiores produtores mundiais de tomate, porém grande parte da produção é perdida devido ao ataque de Bemisia tabaci (Gennadius biótipo B. Entre as táticas de controle dessa praga num manejo integrado de pragas, pode-se relacionar a resistência de plantas. Avaliou-se a preferência para oviposição de B. tabaci biótipo B por 18 genótipos de tomateiro com diferentes densidades e tipos de tricomas utilizando-se dois métodos e estudou-se a influência dos tricomas nesta preferência, utilizando-se dois métodos para os experimentos de confinamento. Folíolos seccionados do terço superior dos tomateiros (primeiro método e plantas com 30 dias de idade (segundo método foram infestados com moscas-brancas durante 24 h. Para o primeiro experimento, foram realizados testes de correlação linear simples entre o número de insetos e de ovos e o número de tricomas nos tomateiros. O primeiro método foi melhor que o segundo, pois foi mais fácil de ser conduzido e demandou menos tempo para as avaliações, além disso, foi efetivo em discriminar o nível de resistência dos genótipos avaliados. Tricomas glandulares correlacionaram-se negativamente com adultos atraídos e com ovos, e positivamente com adultos capturados. Correlações negativas ocorreram entre o número de tricomas não-glandulares e o número de insetos capturados, e entre o número de tricomas totais e o número de insetos atraídos e capturados. Correlações positivas ocorreram entre o número de tricomas totais e o número de ovos cm-2 e de tricomas não-glandulares e o número de ovos. Ambos os métodos foram eficientes para discriminar os genótipos, principalmente os resistentes, com destaque para LA716, PI134417 e PI134418, que apresentaram altíssima antixenose para oviposição relacionada à presença de tricomas glandulares tipo IV. A preferência para oviposição de B. tabaci pelos genótipos LA1963 e NAV1062 est

  6. A escoliose de branca de neve: protagonistas e sujeitos

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    Ana Cristina Fricke Matte

    2004-11-01

    Full Text Available A comparação de diversas versões de uma mesma história produzidas em diferentes épocas pode ter variadas formas e objetivos. Neste trabalho, apresento uma opção de análise cujo principal objetivo é investigar a relação entre o conceito de protagonista e o conceito de sujeito como reveladora de elementos da opção ideológica de cada versão. 0 objeto da análise são cinco versões de Branca de Neve produzidas para a indústria fonográfica entre 1950 e 1991.

  7. Nuevos registros de especies del género Eretmocerus (Hymenoptera: Aphelinidae, parasitoides de Trialeurodes vaporariorum y el complejo Bemisia tabaci (Hemiptera: Aleyrodidae en Argentina New records of species of the genus Eretmocerus (Hymenoptera: Aphelinidae, parasitoids of Trialeurodes vaporariorum and Bemisia tabaci complex (Hemiptera: Aleyrodidae in Argentina

    Directory of Open Access Journals (Sweden)

    Silvia N. López

    2008-06-01

    Full Text Available El objetivo de este trabajo es dar a conocer nuevos registros y distribuciones de las especies del género Eretmocerus Haldeman, parasitoides de las dos especies de mosca blanca que tienen mayor importancia económica en cultivos hortícolas y ornamentales en Argentina. Una especie de Eretmocerus Haldeman fue hallada parasitando a Trialeurodes vaporariorum (Westwood en Santa Fe y Buenos Aires; por sus caracteres morfológicos, se encuentra en el grupo californicus, cercana a corni Haldeman, podría tratarse de una nueva especie. Asimismo, se amplía la distribución geográfica de Eretmocerus mundus Mercet, enemigo natural del complejo Bemisia tabaci (Gennadius, a las provincias de San Juan y Buenos Aires.The objective of this paper is to report new records of species of the genus Eretmocerus Haldeman, parasitoids of the most important whitefly pest species in vegetables and ornamental crops in Argentina. One species was found parasitizing Trialeurodes vaporariorum (Westwood in Santa Fe and Buenos Aires provinces and it is grouped into californicus group near corni Haldeman, due to its morphological characters. It could be a new species. The known distribution of Eretmocerus mundus Mercet, a parasitoid of Bemisia tabaci (Gennadius, is enlarged to include the provinces of San Juan and Buenos Aires of Argentina.

  8. Redução na produção da soja causada por Bemisia tabaci (Gennadius) biótipo b (Hemiptera: Aleyrodidae) e avaliação de táticas de controle

    OpenAIRE

    Simone Silva Vieira

    2009-01-01

    Objetivou-se com este trabalho estimar a redução na produção de soja causada pela mosca branca e estudar táticas de controle para seu manejo. Os experimentos foram conduzidos em casa de vegetação e área de campo da Embrapa Arroz e feijão e em lavouras de Itauçú e Goiânia, GO. O nível de controle foi avaliado a campo em três níveis de infestação com testemunha sem infestação. Semanalmente contou-se o numero de ninfas/folíolo e no final do ciclo avaliou-se a produção e o peso de ...

  9. Whitefly species (Hemiptera: Aleyrodidae on wild and cultivated plants in the horticultural region of Rosario, Santa Fe, Argentina Especies de moscas blancas (Hemiptera: Aleyrodidae sobre plantas silvestres y cultivadas en la región hortícola de Rosario, Santa Fe, Argentina

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    Gustavo G. Gonsebatt

    2012-06-01

    Full Text Available Whiteflies of economic importance are polyphagous, being able to develop on a large number of cultivated and spontaneous plants. We recorded the whitefly species on vegetable and flower crops and the wild plants associated, under greenhouse and field conditions, for two years. We observed two species: Trialeurodes vaporariorum (Westwood and the Bemisia tabaci complex (Gennadius. T vaporariorum was recorded on 24 plant species (11 families, 12 and 8 of which are new hosts in Argentina and in the world, respectively. The B. tabaci complex was recorded only on flower production systems, on 19 plant species (11 families, 14 and 7 of which are new hosts in Argentina and in the world, respectively. The crops Glycine max (L. and Chrysanthemum morifolium Ramat., the wild species Amaranthus blitum L., Amaranthus quitensis Kunth, Conyza bonariensis (L., Galinsoga parviflora Cav., Sonchus oleraceus L. and Wedelia glauca (Ortega O. Hoffm. ex Hicken were hosts of both species. The only parasitoid recorded was Eretmocerus californicus near corni Haldeman (Hymenoptera: Aphelinidae from T. vaporariorum. This study, which is the first systematic survey of host plants in the region, intends to provide a better knowledge of the range of whiteflies host plants in Argentina.Las moscas blancas de importancia económica son polífagas y capaces de desarrollarse sobre numerosas plantas cultivadas y espontáneas. Registramos las especies de moscas blancas sobre cultivos hortícolas y de flores, y sobre las plantas silvestres asociadas. Observamos dos especies: Trialeurodes vaporariorum (Westwood y el complejo Bemisia tabaci (Gennadius. T. vaporariorum fue registrada sobre 24 especies de plantas (11 familias, 12 y 8 de las cuales son hospedantes nuevos para Argentina y a nivel mundial, respectivamente. El complejo B. tabaci fue registrado solo en sistemas de producción de flores, sobre 19 especies de plantas (11 familias, 14 y 7 de las cuales son nuevos hospedantes para

  10. HOST PLANT PREFERENCES OF BEMISIA TABACI GENNADIUS

    Institute of Scientific and Technical Information of China (English)

    JINGYing; HUANGJian; MARui-yan; HANJu-cai

    2003-01-01

    The preferences of Bemisia tabaci Gennadius for five host plants:poinsettia, tomato, cabbage,sweet potato and flowering Chinese cabbage, was tested using a Y-tube olfactometer and a desiccator in the labo-ratory. The results show that B. tabaci adults were attracted by the odors of the five plants. The order of prefer-ence was poinsettia > flowering Chinese cabbage > sweet potato > cabbage > tomato. Preference was extremely sig-nificant between poinsettia and the other four plants, and between flowering Chinese cabbage, cabbage and toma-to. There was no significant difference in preference for flowering Chinese cabbage and sweet potato, sweet pota-to, cabbage and tomato or between cabbage and tomato.

  11. Branca de Neve multim?dia: a personagem na literatura, no cinema e nos quadrinhos

    OpenAIRE

    Miranda., Allana Dilene de Ara?jo de

    2011-01-01

    Objetivando estudar a categoria personagem e sua manifesta??o em tr?s diferentes m?dias, este trabalho analisa Branca de Neve e sua constru??o na literatura, no cinema, e nas hist?rias em quadrinhos. O corpus utilizado foi o conto Branca de Neve e os sete an?es, assinado pelos irm?os Wilhelm e Jacob Grimm; a anima??o de 1937, produzida pelos est?dios Disney, hom?nima; e o primeiro volume da miniss?rie As mil e uma noites, derivada da revista mensal F?bulas, de Bill Willingham. Nos tr?s primei...

  12. Estadísticos vitales de Bemisia tabaci biotipo B en frijol e interacción con el parasitoide Amitus fuscipennis: Life history parameters and absence of hostparasitoid interaction with Amitus fuscipennis Bemisia tabaci biotype B in bean

    Directory of Open Access Journals (Sweden)

    María del Rosario Manzano Martínez

    2009-10-01

    Full Text Available Se determinaron los estadísticos vitales de la mosca blanca Bemisia tabaci biotipo B en condiciones de laboratorio (26 °C ± 2 °C y 80 ± 5 % de HR en fríjol cultivar ICA-Pijao. Los valores promedios fueron: longevidad 34 ± 1.64 días, fecundidad de 211.4 ± 15.1 huevos/hembra y tasa de oviposición de 6.1 ± 0.28 huevos/día. La tasa neta reproductiva fue de 137.8. El tiempo generacional de 43.8 días y la tasa intrínseca de crecimiento poblacional (r m de 0.125. Estos valores son coincidentes con los reportados en la literatura e indicaron la utilidad del frijol (Phaseolus vulgaris L ICA-Pijao para la multiplicación de B. tabaci. No se logró la reproducción de Amitus fuscipennis en B. tabaci. Estudios de comportamiento mostraron que el parasitoide permaneció solo 617.3 seg en promedio en foliolos infestados con la mosca blanca, la mayor parte del tiempo lo invirtió en caminar (46.4%, limpiarse el cuerpo (35.6% y permanecer quieta (16.7%. A. fuscipennis solo tocó una vez accidentalmente una ninfa de B. tabaci, pero no la examinó con las antenas ni la ovipositó. Los resultados indican que A. fuscipennis no es un enemigo natural potencial de B. tabaci biotipo B.Life-history parameters of the whitefly Bemisia tabaci biotipo B were determined at laboratory conditions at 26 °C ± 2 °C y 80 ± 5 % de RH on bean ICA-Pijao. Mean longevity of the whitefly was 34 ± 1,64 days, mean total fecundity was 211,4 ± 15,1 eggs per female with a daily oviposition rate of 6,1 ± 0,28 eggs per day. Net reproduction rate was 137,8. Generation Time was 43,8 days and the intrinsic rate of population increase r m was 0,125. These values are according to previous ones reported and support usefulness of ICA-Pijao bean for B. tabaci rearing. It was not possible to rear Amitus fuscipennis from B. tabaci. Behaviour studies showed that the parasitoid stayed only average 617,3 s on whitefly infested leaflets. It invested most of the time walking (46

  13. Pareto, Mosca e a metodologia de uma nova ciência política

    OpenAIRE

    Bianchi,Alvaro

    2016-01-01

    O artigo investiga os debates metodológicos existentes no processo de institucionalização a ciência política italiana, no final do século XIX e início do XX. Gaetano Mosca e Vilfredo Pareto almejavam um conhecimento científico da política que fosse construído de acordo com parâmetros inspirados nas ciências naturais. Mosca advogou fortemente em favor de um método histórico que permitiria encontrar nas instituições as forças psicológicas que garantiriam a regularidade dos fenômenos políticos. ...

  14. Marx or Mosca? An inquiry into the foundations of ideocratic regimes

    OpenAIRE

    Best, Heinrich

    2012-01-01

    "In John Higley's and Michael Burton's taxonomy of elite settings, 'ideocratic elites' are represented by regimes of the Soviet type. These regimes based their rule on an egalitarian ideology that legitimized inequalities as temporary abnormalities. According to Marx the abolition of private ownership of the means of production would ultimately lead to a classless society. Gaetano Mosca questioned this claim and argued that families would maintain and even strengthen their function in produci...

  15. El vuelo de la mosca: Beelzebub en las artes

    Directory of Open Access Journals (Sweden)

    Aragonés Estella, Esperanza

    2002-12-01

    Full Text Available En gran número de composiciones pictóricas, datadas desde mediado el s. XV hasta el primer tercio del s. XVI, encontramos representada una mosca. El motivo del insecto se encuentra por primera vez, casi simultáneamente, en una obra de un artista flamenco y en otra de un artista hispano, aunque como veremos el significado de la mosca es muy distinto en una y otra composición. Desde estos inicios se adopta con rapidez en varios autores italianos, de aquí pasa a artistas del sur de Alemania, y continúa posándose en cuadros de pintores flamencos, donde ocupa un lugar destacado entre las figuras sagradas y en bodegones. Tradicionalmente el motivo de la mosca se había visto desprovisto de significado, su intención era anecdótica o al menos con un valor ilusionista, un trompe l'oeil para aquel que la veía en el cuadro....

  16. Insecticide resistance in Bemisia tabaci from Cyprus

    Institute of Scientific and Technical Information of China (English)

    Vassilis Vassiliou; Maria Emmanouilidou; Andreas Perrakis; Evangelia Morou; John Vontas; Anastasia Tsagkarakou; Emmanouil Roditakis

    2011-01-01

    A comprehensive study on the Bemisia tabaci(biotype B)resistance to neonicotinoid insecticides imidacloprid,acetamiprid and thiamethoxam,and pyrethroid bifenthrin was conducted in Cyprus.The resistance level to eight field-collected B.tabaci populations was investigated.The activities of enzymes involved in metabolic detoxification and the frequencies of pyrethroid and organophosphates target site resistance mutations were determined.Moderate to high levels of resistance were detected for imidacloprid(resistance factor[RF]77-392)and thiamethoxam(RF 50-164)while low resistance levels were observed for acetamiprid(RF 7-12).Uniform responses by the Cypriot whiteflies could be observed against all neonicotinoid insecticides.No cross-resistance between the neonicotinoids was detected as well as no association with the activity of the P450 microsomal oxidases.Only imidacloprid resistance correlated with carboxylesterase activity.Low to extremely high resistance was observed for insecticide bifenthrin(RF 49-1 243)which was associated with the frequency of the resistant allele in the sodium channel gene but not with the activity of the detoxification enzymes.Finally,the F331W mutation in the acetylcholinesterase enzyme ace1 gene was fixed in all B.tabaci populations from Cyprus.

  17. Effect of climate change on Bemisia tabaci in Southeastern USA

    Science.gov (United States)

    Traditional and molecular approaches can be used to improve cultivated watermelon (Citrullus lanatus var. lanatus) against whiteflies. The Bemisia tabaci (Hemiptera: Aleyrodidae) whitefly complex attacks many crops on a global scale. It is very adaptive, and it feeds on over 1,000 diverse species of...

  18. Resistance mechanisms against Bemisia tabaci in wild relatives of tomato

    NARCIS (Netherlands)

    Elsen, van den F.H.W.

    2013-01-01

    The silverleaf whitefly (Bemisia tabaciGenn.) poses a serious threat to tomato cultivation. A large part of the damage is done directly through heavy host plant colonization. Colonization has a negative impact on the plant, as the whitefly takes up nutrients from the phloem and induces phytotoxic re

  19. Phytoseiid predators as potential biological control agents for Bemisia tabaci

    NARCIS (Netherlands)

    Nomikou, M.; Janssen, A.; Schraag, R.; Sabelis, M.W.

    2001-01-01

    Mites of the family Phytoseiidae are known to be predators of whiteflies in several agroecosystems, especially of Bemisia tabaci Gennadius, a pest with high resistance to chemical insecticides that occurs in greenhouses in temperate regions. We collected predatory mites that were found to co-occur

  20. Caracterização da variabilidade da mosca do berne Dermatobia hominis (Diptera : oestridae) atraves de dois marcadores moleculares

    OpenAIRE

    Taila Andrade Lemos

    2000-01-01

    Resumo: Dermatobia hominis (Linnaus Jr.) conhecida popularmente como mosca do berne. É uma das principais causadoras de miíase primária em vertebrados. sendo uma das principais pragas da pecuária nacional. causando grandes prejuízos à industria coureira. laticínios e frigoríficos. A mosca do berne apresenta uma biologia interessante e ciclo de vida bastante peculiar. o que dificuta a observação da espécie na natureza e a manutenção desta em laboratório. Por estes motivos. a caracterização da ...

  1. Eficácia de atrativos alimentares na captura de moscas-das-frutas em pomar de citros

    OpenAIRE

    Raga, Adalton; Machado,Rogério Amaro; Dinardo,Welci; Strikis,Pedro Carlos

    2006-01-01

    As moscas-das-frutas (Diptera: Tephritoidea) são importantes pragas de frutas cítricas no Estado de São Paulo, principalmente Anastrepha fraterculus (Wied.) e Ceratitis capitata (Wied.). O objetivo deste estudo foi medir a eficiência dos atrativos alimentares para monitoramento de moscas-das-frutas, em pomar de citros. O delineamento experimental adotado foi de blocos ao acaso com cinco tratamentos e cinco repetições. O ensaio foi instalado em 30/9/2003 e desenvolvidopor nove semanas. Os atra...

  2. Dietas larvais alternativas para criação massal da mosca da bicheira, Cochliomyia hominivorax

    Directory of Open Access Journals (Sweden)

    Thiago Mastrangelo

    2014-04-01

    Full Text Available A criação massal da mosca da bicheira, Cochliomyia hominivorax (Diptera: Calliphoridae, para programas que utilizam a Técnica do Inseto Estéril nas Américas faz parte de um dos maiores programas do mundo de criação de insetos em larga escala. A maior parte do custo e do trabalho necessários para a produção massal está relacionada com a dieta larval, o que torna importante o seu aprimoramento levando-se em conta sua eficiência, custo e praticidade. Neste trabalho, foram realizados dois bioensaios com dietas alternativas feitas a partir de produtos disponíveis no mercado brasileiro com o objetivo de avaliar a viabilidade e eficiência dessas dietas para criações de mosca da bicheira no Brasil. Foram testadas duas dietas líquidas (tendo como bulking agents bagaço de cana ou fibra de coco, uma de carne, e outra de gel. Os parâmetros biológicos (peso das larvas, viabilidade larval, peso de pupas, porcentagem de emergência de adultos e razão sexual estiveram, em todos os casos, dentro de parâmetros satisfatórios para a criação laboratorial de C. hominivorax e as dietas não diferiram estatisticamente entre si. Devido a vantagens importantes, como alta viabilidade larval e menor custo, recomenda-se a dieta de gel para as criações de larvas da mosca da bicheira no Brasil.

  3. Capacidad reguladora de Chrysoperla externa (Hagen sobre mosca blanca Trialeurodes vaporariorum (Westwood en tomate bajo invernadero

    Directory of Open Access Journals (Sweden)

    Mayerly Alejandra Castro-Lopez

    2016-11-01

    Full Text Available Trialeurodes vaporariorum Westwood (Hemíptera: Aleyrodidae es uno de los principales limitantes del cultivo de tomate Solanum lycopersicum, por generar problemas directos e indirectos en este sistema de producción; para el manejo de este insecto (mosca blanca se acude a excesivas aplicaciones de productos de síntesis química, sin obtener los mejores resultados. Este estudio consistió en evaluar, en condiciones de invernadero, la capacidad reguladora de Chrysoperla externa Hagen (Neuróptera: Chrysopidae sobre la mosca blanca presente en tomate. En plantas infestadas con individuos de T. vaporariorum se adicionó C. externa en niveles poblacionales de 80, 160 y 240 individuos en estado larval por planta, y se contó con un testigo sin depredador. Se empleó un diseño completamente al azar en condiciones de invernadero (temperatura promedio de 20 ºC y humedad relativa del 60 %. Se observaron diferencias estadísticamente significativas entre las densidades del depredador, con infestaciones de 35, 52 y 53 % de T. vaporariorum (tras cuatro semanas, correspondientes a las liberaciones de 240, 160 y 80 individuos por planta, respectivamente. Se observó que las plantas del testigo presentaron menor altura y número de ramas, respecto de los tratamientos en los cuales había presencia del depredador C. externa.

  4. Efectividad de una mezcla de cipermetrina y clorpirifós para el control de la mosca Haematobia irritans

    Directory of Open Access Journals (Sweden)

    Gustavo López V.

    2011-05-01

    Full Text Available Objetivo. Determinar la eficacia de una mezcla de Cipermetrina y Clorpirifós contra la mosca de los cuernos Haematobia irritans. Materiales y métodos. Se utilizaron 24 novillas Holstein con infestación natural de moscas Haematobia irritans y se asignaron aleatoriamente a dos grupos, tratado y control, de 12 animales cada uno. El grupo tratado recibió el producto por aspersión en dilución 1:800, utilizando 1 litro por cada 100 kilos de peso. Se hicieron conteos de moscas antes del tratamiento y en los días 7, 14 y 21 post-aplicación para evaluar la eficacia del producto. Resultados. Los porcentajes de eficacia del producto fueron de 89.9, 97.4 y 99.5%, para los días 7, 14 y 21 post-tratamiento, respectivamente. Conclusiones. La mezcla de Cipermetrina y Clorpirifós resultó altamente eficaz contra la mosca de los cuernos Haematobia irritans y surge como una nueva alternativa para el control del parásito, especialmente donde se presente resistencia a las diferentes moléculas que contienen los productos comerciales.

  5. Moscas frugívoras (Diptera, Tephritoidea coletadas em Aquidauana, MS Frugivorous flies (Diptera, Tephritoidea collected in Aquidauana, MS

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    Sérgio Roberto Rodrigues

    2006-03-01

    Full Text Available No Brasil as moscas frugívoras são pragas importantes de frutas e hortaliças. O conhecimento da flutuação populacional dessas espécies em cada bioma é um importante requisito para a adoção de estratégia de controle de pragas nos agroecossistemas. O objetivo desse trabalho foi avaliar a diversidade de espécies de moscas-das-frutas infestantes de frutas silvestres e cultivadas em Aquidauana, MS. Vinte e uma espécies de frutas foram amostradas de fevereiro de 2003 a janeiro de 2004. As espécies de Tephritidae encontradas foram: Anastrepha striata Schiner, 1868, Anastrepha obliqua (Macquart, 1835 e Ceratitis capitata (Wiedemann, 1824. Os frugívoros Lonchaeidae e Muscidae encontrados foram: Neosilba sp. e Atherigona orientalis (Schiner, 1868, respectivamente. Um total de 2.568 moscas foram coletadas, das quais 2.394 representadas pela mosca-do-Mediterrâneo C. capitata. A associação entre moscas frugívoras e espécies de frutas é discutida.In Brazil, frugivorous flies represent important pests of fruits and vegetables. Information on populational fluctuation of these species in each biome is an important requirement for the adoption of a strategy of pest control in the agroecosystems. The objective of this paper is to assess the diversity of fruit fly species occurring in wild and cultived fruits in Aquidauana, MS. Twenty-nine fruit species were sampled from February 2003 to January 2004. The Tephritidae species recovered were: Anastrepha striata Schiner, 1868, Anastrepha obliqua (Macquart, 1835 and Ceratitis capitata (Wiedemann, 1824. The frugivorous Lonchaeidae and Muscidae recovered were: Neosilba sp. and Atherigona orientalis (Schiner, 1868, respectively. A total of 2.568 flies were obtained, from which 2.394 flies were the Mediterranean fruit fly, C. capitata. The association between frugivorous flies and the fruit species is discussed.

  6. Faca e armas brancas: um campo lexical em Grande sertão: veredas

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    Maria Célia de Moraes Leonel

    2001-02-01

    Full Text Available

    Estudo do campo lexical da palavra faca e de outros lexemas que se referem às armas brancas em Grande sertão: veredas de Guimarães Rosa, tendo-se em vista os significados dos vocábulos no universo de sentidos do romance. A orientação teórica centra-se, sobretudo, nas propostas de H. Geckeler e ainda nas de J. Lyons.

  7. Contribución al Estudio de las Moscas Anastrephas en Colombia.

    Directory of Open Access Journals (Sweden)

    González Mendoza Rafael

    1952-11-01

    Full Text Available 1. Colombia tiene amplias posibilidades de desarrollar una industria frutícola floreciente dadas las excepcionales condiciones de ubicación geográfica, diversidad de climas y de suelos. 2. La deficiente producción frutera actual es el resultado de una reunión de factores adversos, entre los que resalta el desconocimiento de los problemas científicos que afectan a dicha industria. En este aspecto, los problemas fitosanitarios, abandonados y faltos de investigación, ocupan lugar preponderante. 3. Las moscas Anastrephas constituyen la plaga más importante de la fruticultura nacional, y por esta razón, un estudio sobre estos insectos es un tema de importancia. 4. Las principales "moscas de las frutas" pertenecen dentro de la familia Trypetidae, a los géneros: Dacus, Rhaglethis, Ceratitis, Dactrocera y Anastrepha. 5. Los nombres comunes con que se conocen las moscas Anastrephas varían de un país a otro y se relacionan particularmente con el lugar de origen de las distintas especies o la fruta determinada como preterida por la mosca en una localidad. En Colombia la denominación vernácula más difundida es la de "gusano de las frutas". También se nombra el insecto como "mosca o gusano del mango" o "gusano de la guayaba". 6. Los nombres científicos de las moscas distinguen a una, gran cantidad de especies. En Colombia, varios autores han reportado la existencia de las especies A.fraterculus, A. ludens, A. mombinpracoptans, A. pikeli y A. serpentina. Todas estas especies inciden en las regiones colombianas comprendidas entre 0 y 2000 metros de altura, es decir, en casi todas las regiones agrícolas importantes (frutales, café, cacao de temperaturas entre 14° y 30° C. 7. Las moscas Anastrephas están confinadas casi exclusivamente al continente americano entre las latitudes 27° N. y 35° S. Particularmente, la especie A. fraterculus, una de las más difundidas en Colombia, fué determinada por Wiedemann (1830

  8. COMPATIBILIDADE DO INSETICIDA THIAMETHOXAM COM FUNGICIDAS UTILIZADOS NO TRATAMENTO DE SEMENTES DE FEIJOEIRO COMPATIBILITY OF THE INSECTICIDE THIAMETHOXAM WITH FUNGICIDES APPLIED TO COMMON BEAN SEEDS

    Directory of Open Access Journals (Sweden)

    Rosana Gonçalves Barros

    2007-09-01

    Full Text Available

    A mosca-branca (Bemisia argentifolli Bellows & Perring tem causado sérios prejuízos em muitas áreas produtoras de feijão no Brasil. O dano indireto através da transmissão do vírus do mosaico dourado é um dos fatores limitantes na produção do feijão, podendo causar perdas de até 100%. Uma das medidas recentemente desenvolvidas para o controle desta praga é o tratamento das sementes com inseticida. Neste trabalho foi testada a compatibilidade do inseticida thiamethoxam com alguns dos fungicidas utilizados para tratamento de sementes de feijão destinadas ao plantio (difenoconazole, fludioxonil e carboxin. As variáveis utilizadas na avaliação foram: porcentagens de germinação, de sanidade das sementes e de eficiência de controle da mosca-branca. Considerando todas as variáveis, constatou-se que não houve incompatibilidade do inseticida com os fungicidas utilizados. Os tratamentos thiamethoxam+carboxin e thiamethoxam+fludioxonil foram os que apresentaram maior eficiência no controle de fungos incidentes em sementes e da mosca-branca em plântulas até os onze dias após a emergência.

    PALAVRAS-CHAVE: Mosca-branca; Bemisia argentifolli; fungos de sementes; controle químico.

    The white fly (Bemisia argentifolli Bellows & Perring causes serious damage to the common bean crop in Brazil. The indirect damage through the transmission of bean gold mosaic virus can cause losses of up to 100%. One measure recently developed to control this pest is insecticide seed dressing. In this study, the compatibility of the insecticide thiamethoxam with the fungicides used for dry beans seed dressing was tested. These treatments included the fungicides difenoconazole, fludioxonil and carboxin. The variables evaluated were

  9. Reconocimiento de parasitoides naturales de moscas del género Dasiops Rondani (Díptera: Lonchaeidae) en pasifloras cultivadas de Cundinamarca y Boyacá, Colombia

    OpenAIRE

    Santamaría Galindo, Maikol Yohanny

    2012-01-01

    Las moscas del género Dasiops Rondani son los insectos plaga de mayor importancia económica en pasifloras cultivadas debido a que las moscas adultas ovipositan en botones florales y flores polinizadas y la larva consume su interior. Para su control se implementan estrategias convencionales basadas en la aplicación tipo calendario de insecticidas que no han tenido resultados efectivos. Esto ha venido afectando la sostenibilidad de los cultivos de pasifloras y causado deterioro de la biodiversi...

  10. DIVERSIDADE DE BROMELIACEAE NA APA SANTUÁRIO ECOLÓGICO DA PEDRA BRANCA, CALDAS, MG

    Directory of Open Access Journals (Sweden)

    Amália Eugênia Matavelli Rosa

    2014-10-01

    Full Text Available A Área de Proteção Ambiental Santuário Ecológico da Pedra Branca localiza-se no município de Caldas, sul de Minas Gerais. Nos seus 119 km2, a altitude é sempre superior a 1000m, chegando a 1760m no seu ponto culminante. O presente estudo objetiva o conhecimento da diversidade de Bromeliaceae, bem como sua distribuição por fisionomias vegetais e um diagnóstico sobre o estado de conservação da área. Durante os meses de julho/2009 e dezembro/2010 foram realizadas coletas abrangendo as diversas fisionomias vegetais desta unidade de conservação. Foram catalogadas 19 espécies de Bromeliaceae distribuídas por 5 fisionomias vegetais. A maior diversidade de Bromeliaceae ocorre ao longo da Serra da Pedra Branca, seja pela integridade da flora ou pela combinação entre altitude, clima e relevo que propiciam o surgimento de um mosaico de fisionomias.

  11. DEL CIUDADANO CAPACITARIO DE SIEYÈS A LAS CLASES POLÍTCAS DE MOSCA

    OpenAIRE

    Maria Elena Ludeña Párján

    2009-01-01

    En el presente artículo se trata de revisar las diferentes concepciones de clase política planteadas en el trabajo de Gaetano Mosca, y la concepción de ciudadano capacitario de Emmanuel Sieyès, basándonos en la idea fundamental que ese ciudadano capacitario que plantea Sieyès será la base para la formación de clases políticas en las sociedades modernas. El objetivo general que nos planteamos para este trabajo es estudiar, a la luz de la teoría de las clases políticas si la proposición de ciu...

  12. Dinâmica Populacional de Mosca-Branca, Incidência do Mosaico Dourado do Feijoeiro e Alternativas de Controle da Praga no "Cultivo das Secas" no Cerrado

    Directory of Open Access Journals (Sweden)

    Luciana Claudia Toscano

    2016-04-01

    Abstract. The objectives of this research were to study the population dynamics of whitefly and golden bean mosaic from planting to flowering of culture; check the efficiency of chemical and microbial insecticides to control the whitefly; and analyze some phytotechnical parameters in the bean crop “dry” after controlling the pest. The test was developed in the experimental area of the UEMS / Cassilândia - MS in (DBC, with four replications and eight treatments: 1 control, 2 thiamethoxan (50g ai ha-1, 3 acetamiprid (60g ai ha-1, 4 piryproxyfen (100g ai ha-1, 5 spiromesifen (96g ai ha-1, 6 imidacloprid (160g ai ha-1, 7 methamidophos (300g ai ha-1 and 8 Beauveria bassiana (Bals.-Criv. Vuill. (25 X 10 11 conidia ha-1. Counted the number of eggs and nymphs in 25 leaflets per plot and adults were captured and counted using yellow sticky traps (prior, and continuously in the witnesses. The evaluations were performed at seven and 14 days after application (DAA, and weekly until 51 (DAE in the control. The occurrence of eggs, nymphs and adult whitefly started up at 30 days after emergence (DAE, reducing to 51 DAE, the culture of flowering stage. For the number of eggs at seven DAA no significant difference between treatments, and at 14 DAA all treatments differed from the control except treatment B. bassiana. For nymphs, at seven and 14 DAA, piryproxifen showed better control again. At seven DAA it was found that piryproxyfen had lower average in the number of adults compared to the control.

  13. Quirópteros do Parque Estadual da Pedra Branca, Rio de Janeiro, Brasil (Mammalia, Chiroptera Bats from Pedra Branca State Park, Rio de Janeiro, Brazil (Mammalia, Chiroptera

    Directory of Open Access Journals (Sweden)

    Daniela Dias

    2002-12-01

    Full Text Available A survey of chiropteran fauna was conducted during the period from March 1994 to May 1998 in Pedra Branca State Park, Rio de Janeiro, Rio de Janeiro State. A total of 681 specimens of 24 species were recorded: Chrotopterus auritus (Peters, 1856; Micronycteris megalotis (Gray, 1842; Micronycteris minuta (Gervais, 1856; Mimmon bennettii (Gray, 1838; Phyllostomus hastatus (Pallas, 1767; Tonatia bidens (Von Spix, 1823; Lonchophylla bokermanni Sazima, Vizotto & Taddei, 1978; Lonchophylla mordax Thomas, 1903; Anoura caudifera (E. Geoffroy, 1818; Glosso-phaga soricina (Pallas, 1766; Carollia perspicillata (Linnaeus, 1758; Artibeus fimbriatus Gray, 1838; Artibeus lituratus (Olfers, 1818; Artibeus obscuras Schinz, 1821; Chiroderma doriae Thomas, 1891; Platyrrhinus lineatus (E. Geoffroy, 1810; Platyrrhinus recifinus (Thomas, 1901; Sturnira lilium (E. Geoffroy, 1810; Vampyressa pusilla (Wagner, 1843; Desmodus rotundus (E. Geoffroy, 1810; Diphylla ecaudata Von Spix, 1823; Eptesicus brasiliensis (DesMarest, 1819; Myotis nigricans (Schinz, 1821 and Molossus molossus (Palas, 1766. One external (forearm length and 13 cranial meansurements were studied for 23 species. The meansurements of male and female specimens were treated separately. Comments about some taxonomic respects for some species studied are also included.

  14. Hongos de importancia agrícola presentes en moscas de la fruta del valle de Ica, Perú

    Directory of Open Access Journals (Sweden)

    Carlos E. Tipismana

    2013-05-01

    Full Text Available El objetivo del presente trabajo fue aislar e identificar hongos de especímenes de moscas de la fruta de los géneros Ceratitis (Macleay y Anastrepha (Schiner, del valle de Ica, Perú. Se aislaron hongos pertenecientes a los géneros Alternaria, Aspergillus, Cladosporium, Mucor, Penicillium, Rhizoctonia, Rhizopus y Trichoderma;así como levaduras y micelios estériles. Los recuentos de hongos presentaron rangos entre 8x103 a 8x104 UFC/g para el género Ceratitis; y 7x103 a 7x104 UFC/g para el género Anastrepha. El IVI% (Índice de Valor de Importancia demostró que Cladosporium es el género con mayor valor ecológico con un 78,05%. El Índice de Similitud de especies de hongos entre ambos géneros de mosca de la fruta analizados fue 0,5. Los resultados obtenidos confirman la presencia de hongos en moscas de la fruta; y se deduce el posible impacto de estos dípteros en el área agrícola como potenciales agentes vectores de enfermedades fúngicas para los cultivos locales de importancia económica.

  15. Moscas-das-frutas (Diptera: Tephritidae em um pomar de goiabeira, no semiárido brasileiro

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    Elton Lucio Araujo

    2013-06-01

    Full Text Available As moscas-das-frutas (Diptera: Tephritidae são pragas-chave na cultura da goiabeira Psidium guajava L., com predominância de diferentes espécies de acordo com a região produtora no Brasil. Os objetivos do presente trabalho foram conhecer a diversidade e analisar parâmetros faunísticos das moscas-das-frutas obtidas em um pomar de goiabeira, no município de Cruzeta, Rio Grande do Norte, situado no semiárido brasileiro. As moscas-das-frutas foram coletadas semanalmente, com auxílio de armadilhas McPhail, tendo como atrativo proteína hidrolisada a 5% v/v. Foram registradas cinco espécies no pomar estudado: Ceratitis capitata (Wied., Anastrepha zenildae Zucchi, Anastrepha sororcula Zucchi, Anastrepha obliqua (Macquart e Anastrepha dissimilis Stone. Ceratitis capitata foi a espécie mais frequente, constante e dominante, considerada como uma praga invasiva, potencial em pomares de goiabeira no semiárido brasileiro.

  16. The family Bignoniaceae in the Environmental Protection Area Serra Branca, Raso da Catarina, Jeremoabo, Bahia, Brazil

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    Luiza Regina Silva

    2016-12-01

    Full Text Available Bignoniaceae comprises 82 genera and 827 species distributed mostly in tropical and subtropical regions, with a few species in temperate climates, and is most diverse in South America. The Brazil is the center of diversity for the group, with about 406 species in 33 genera, of which 22 genera and 90 species occur in the Caatinga. The floristic survey of Bignoniaceae in the Environmental Protection Area Serra Branca included analysis of 31 specimens collected from August 2009 to February 2012. The analyses were supplemented with dried collections from the following herbaria: ALCB, HRB and HUEFS. Nine genera and 11 species were recorded: [Anemopaegma Mart ex DC; Bignonia L.; Cuspidaria DC.; Fridericia Mart.; Handroanthus Mattos; Jacaranda Juss; Lundia DC.; Mansoa DC. and Tabebuia Gomes ex DC.]. Fridericia was the most representative genus with three species. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data of the geographical distribution, reproductive phenology and comments about the species.

  17. The family Passiloraceae in APA Serra Branca/Raso da Catarina, Jeremoabo, Bahia, Brazil

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    Jéssica Vieira dos Santos

    2016-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n1p11 This work presents a loristic survey of the family Passiloraceae in APA Serra Branca/Raso da Catarina, located in the municipality of Jeremoabo, Bahia. The family has a pantropical distribution and includes about 20 genera and 600 species. In Brazil there are four genera, Ancistrothyrsus, Dilkea, Mitostemma and Passilora, the latter being the most diverse. In the Caatinga biome there are 29 species, including one species of Mitostemma and the others of Passilora. The samples analyzed were collected from August/2011 to February/2013, and the analyses were supplemented with dried collections kept in the following herbaria: ALCB, HRB and HUEFS. Four species of the genus Passilora were recorded: Passilora cincinnata, P. foetida, P. luetzelburgii and P. setacea. Comments about the morphology and taxonomy, data on geographical distribution and phenology, illustrations, and a key to the taxa studied are provided.

  18. The family Passifloraceae in APA Serra Branca/Raso da Catarina, Jeremoabo, Bahia, Brazil

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    Jéssica Vieira dos Santos

    2016-02-01

    Full Text Available This work presents a floristic survey of the family Passifloraceae in APA Serra Branca/Raso da Catarina, located in the municipality of Jeremoabo, Bahia. The family has a pantropical distribution and includes about 20 genera and 600 species. In Brazil there are four genera, Ancistrothyrsus, Dilkea, Mitostemma and Passiflora, the latter being the most diverse. In the Caatinga biome there are 29 species, including one species of Mitostemma and the others of Passiflora. The samples analyzed were collected from August/2011 to February/2013, and the analyses were supplemented with dried collections kept in the following herbaria: ALCB, HRB and HUEFS. Four species of the genus Passiflora were recorded: Passiflora cincinnata, P. foetida, P. luetzelburgii and P. setacea. Comments about the morphology and taxonomy, data on geographical distribution and phenology, illustrations, and a key to the taxa studied are provided.

  19. Medicinal use of insects in the county of Pedra Branca, Santa Terezinha, Bahia, Brazil

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    Josué Marques Pacheco

    2005-05-01

    Full Text Available This paper deals with the use of insects as medicinal resources by inhabitants of the county of Pedra Branca, which is located in the interior of Bahia State, northeastern Brazil. The survey was carried out from February to May 2001 by conducting open-ended interviews with 52 informants of both sexes, aged over 30. The value of each of the entomotherapeutic resources was estimated through its relative importance (RI, a versatility measure. A total of 27 kinds of insects was recorded as being medicinally useful in the treatment of locally diagnosed illnesses and symptoms. The order Hymenoptera was predominant, with 12 kinds represented. The recording of the usage of medicinal insects in this locality provides a relevant contribution to the phenomenon of zootherapy. Biochemical and pharmacological studies are needed to promote the development of new drugs for the improvement of human health.

  20. PARASITOIDES (HYMENOPTERA DE MOSCAS-DAS-FRUTAS (DIPTERA: TEPHRITIDAE NO SEMIÁRIDO DO ESTADO DO CEARÁ, BRASIL

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    ELTON LUCIO ARAUJO

    2015-09-01

    Full Text Available RESUMO As moscas-das-frutas (Diptera: Tephritidae, Anastrepha spp. e Ceratitis capitata(Wiedemann, são importantes pragas da fruticultura no Brasil. Para desenvolver um sistema sustentável de manejo integrado para este grupo de pragas, é fundamental conhecer os parasitoides (Hymenoptera que podem regular as populações destes tefritídeos. Portanto, o objetivo deste estudo foi relatar a diversidade, a distribuição geográfica e as relações tritróficas dos himenópteros parasitoides de moscas-das-frutas, na região do Baixo Jaguaribe, no semiárido do Estado do Ceará, Brasil. Foram realizadas coletas de frutos em sete municípios da região, no período de maio de 2010 amaio de 2013. Os frutos foram levados para o laboratório, onde foram contados, pesados, colocados em bandejas plásticas com vermiculita e fechadas com tecido voile. Após sete dias, a vermiculita foi peneirada para a obtenção dos pupários das moscas-das-frutas que, em seguida, foram contados e acondicionados em placas de Petri, onde permaneceram até a emergência dos adultos (moscas e/ou parasitoides. Quatro espécies de parasitoides foram encontradas: Doryctobracon areolatus(Szépligeti, Opius bellus Gahan, Utetes anastrephae(Viereck (Braconidae e Tetrastichus giffardianusSilvestri (Eulophidae,sendo o mais frequente e com maior distribuição geográfica na região, D. areolatus. Doryctobracon areolatusfoi mais comum em associação com espécies de Anastrepha - A. sororcula Zucchi, A. obliqua (Mcquart e A. zenildae Zucchi, em frutos nativos e com C. capitata em frutos exóticos. Tetrastichus giffardianus foi obtido apenas em associação com C. capitata, em frutos nativos e exóticos. Estas informações podem servir de base para inserção de parasitoides em futuros programas de manejo integrado de moscas-das-frutas, nas condições do Semiárido brasileiro.

  1. Monitoring changes in bemisia tabaci susceptibility to neonicotinoid insecticides in Arizona and California

    Science.gov (United States)

    Laboratory bioassays were carried out on field-collected and laboratory strains of Bemisia tabaci to evaluate relative toxicities of four neonicotinoid insecticides: acetamiprid, dinotefuran, imidacloprid and thiamethoxam. Susceptibility to all four neonicotinoids in leaf-uptake bioassays varied co...

  2. Feeding Experience of Bemisia tabaci (Hemiptera: Aleyrodidae) Affects Their Performance on Different Host Plants

    Science.gov (United States)

    Shah, M. Mostafizur Rahman; Liu, Tong-Xian

    2013-01-01

    The sweetpotato whitefly, Bemisia tabaci biotype B is extremely polyphagous with >600 species of host plants. We hypothesized that previous experience of the whitefly on a given host plant affects their host selection and performance on the plants without previous experience. We investigated the host selection for feeding and oviposition of adults and development and survival of immatures of three host-plant-experienced populations of B. tabaci, namely Bemisia-eggplant, Bemisia-tomato and Bemisia-cucumber, on their experienced host plant and each of the three other plant species (eggplant, tomato, cucumber and pepper) without previous experience. We found that the influence of previous experience of the whiteflies varied among the populations. All populations refused pepper for feeding and oviposition, whereas the Bemisia-cucumber and the Bemisia-eggplant strongly preferred cucumber. Bemisia-tomato did not show strong preference to any of the three host palnts. Development time from egg to adult eclosion varied among the populations, being shortest on eggplant, longest on pepper, and intermediate on tomato and cucumber except for the Bemisia-cucumber developed similarly on tomato and pepper. The survivorship from egg to adult eclosion of all populations was highest on eggplant (80-98%), lowest on pepper (0-20%), and intermediate on tomato and cucumber. In conclusion, the effects of previous experience of whiteflies on host selection for feeding and oviposition, development, and survivorship varied depending on host plants, and host plants play a stronger role than previous experience. Preference of feeding and oviposition by adults may not accurately reflect host suitability of immatures. These results provided important information for understanding whitefly population dynamics and dispersal among different crop systems. PMID:24146985

  3. HISPANISMOS EN EL MUISCA. BOCABULARIO DE L A LENGUA CHIBCHA O MOSCA, MANUSCRITO II/2922

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    Diana Andrea Giraldo Gallego

    2013-01-01

    Full Text Available Este artículo muestra algunos hispanismos en la lengua muisca presentes en el Bocabulario de la Lengua Chibcha o Mosca, manuscrito II/2922 (3, conservado en la Real Biblioteca del Palacio Real de Madrid. El trabajo se llevó a cabo en las siguientes etapas: a búsqueda y selección de los posibles hispanismos en el manuscrito; b consulta etimológica en el Diccionario crítico etimológico castellano e hispánico, en el Tesoro de la Lengua Castellana o Española y, en algunos casos, en el Diccionario de la Lengua Española; c transcripción del préstamo en contexto, y d presentación de aquellos campos en donde se encuentran los hispanismos, ya que estos no solo se dieron en el campo religioso. Asimismo, se exponen las posibles adaptaciones fonéticas de estos hispanismos en el muisca. Palabras clave: lenguas en contacto, préstamo léxico, lengua muisca, manuscritos.

  4. HISPANISMOS EN EL MUISCA. BOCABULARIO DE LA LENGUA CHIBCHA O MOSCA, MANUSCRITO II/2922

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    Diana Andrea Giraldo Gallego

    2013-12-01

    Full Text Available Este artículo muestra algunos hispanismos en la lengua muisca presentes en el Bocabulario de la Lengua Chibcha o Mosca, manuscrito II/2922 (3, conservado en la Real Biblioteca del Palacio Real de Madrid. El trabajo se llevó a cabo en las siguientes etapas: a búsqueda y selección de los posibles hispanismos en el manuscrito; b consulta etimológica en el Diccionario crítico etimológico castellano e hispánico, en el Tesoro de la Lengua Castellana o Española y, en algunos casos, en el Diccionario de la Lengua Española; c transcripción del préstamo en contexto, y d presentación de aquellos campos en donde se encuentran los hispanismos, ya que estos no solo se dieron en el campo religioso. Asimismo, se exponen las posibles adaptaciones fonéticas de estos hispanismos en el muisca.

  5. Psicoanalisi ed educazione: il lavoro di Vera Schmidt e di Sabina Spielrein nell’asilo sperimentale di Mosca (1921-1925

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    Merete Amann Gainotti

    2012-12-01

    Full Text Available Negli anni 1921-1923 a Mosca, sulla scia delle profonde trasformazioni politiche e sociali innescate dalla Rivoluzione di ottobre si colloca un esperimento educativo originale, promosso da Vera Schmidt, una pedagogista formata alle idee psicoanalitiche, che si proponeva di cercare nuove vie educative per la prima infanzia sulla base delle recenti conquiste e conoscenze fornite dalla teoria psicoanalitica di S. Freud. Obiettivo di questo contributo è di fornire un breve excursus storico relativo alla diffusione della psicoanalisi in Unione sovietica e alla fondazione dell'asilo sperimentale di Mosca, di ricordare le figure delle due studiose Vera Schmidt e Sabina Spielrein che hanno animato l'iniziativa, il cui lavoro scientifico è rimasto in ombra rispetto a quello dei loro più famosi colleghi S. Freud e di C.G. Jung; infine si intende rendere conto dei principi educativi che esse cercarono di mettere in pratica nell'asilo sperimentale di Mosca.

  6. First record of occurrence of mosca-negra-dos-citrus, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Sternorrhyncha: Aleyrodidae in Roraima, Brazil = Primeiro registro da ocorrência de mosca-negra-dos-citros, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Aleyrodidae em Roraima

    Directory of Open Access Journals (Sweden)

    Francisco Clemilto da Silva Maciel

    2011-12-01

    Full Text Available The Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae is an important pest of citrus. Originated in Asia, this pest was detected in Brazil for the first time in the State of Para, Brazil in 2001. In the culture of citrus fruits the black fly carries direct and indirect damage, impeding the development and production of plants. In addition to restricting trade in local areas from its occurrence to the presence of the plague, since the A. woglumi quarantine pest is considered present (A2 of high alert in accordance with Instruction No 23, April 29, 2008, established by the Ministério da Agricultura, Pecuária e Abastecimento of the Brazil. The objective of this paper was to record the first occurrence of Aleurocanthus woglumi in the State of Roraima, Brazil.= A mosca-negra-dos-citros, Aleurocanthus woglumi Ashb, (Hemiptera: Aleyrodidae é uma importante praga dos citros. De origem asiática, esta praga foi detectada no Brasil pela primeira vez no estado do Pará no ano de 2001. Na cultura dos citros a mosca-negra acarreta danos diretos e indiretos, prejudicando o desenvolvimento e produção das plantas. Além de restringir o comércio de locais de sua ocorrência para áreas livres da presença da praga, visto que o A. woglumi é considerado praga quarentenária presente (A2 de alerta máximo de acordo com a instrução normativa No 23, de 29 de abril de 2008; estabelecida pelo Ministério da Agricultura, Pecuária e Abastecimento. Objetivou-se com o presente trabalho registrar a primeira ocorrência de mosca-negra-dos-citros no estado de Roraima.

  7. Geophysical Character and Geochemical Evolution of the Mesoproterozoic Figueira Branca Intrusive Suite, SW Amazon Craton (Brazil)

    Science.gov (United States)

    Louro, Vinicius; Cawood, Peter; Mantovani, Marta

    2016-04-01

    The Jauru Terrain hosts the Figueira Branca Intrusive Suite (FBS) in the SW of the Amazon Craton (Brazil). The FBS is a series of 1425 Ma layered mafic intrusions, previously interpreted as anorogenic. The FBS area is located in foreland to the Santa Helena orogen, formed by the subduction of the Rio Alegre Terrain under the Jauru Terrain. Potential field methods (magnetic and gravity), gamma-ray spectrometry, geochemical and isotope data were used to characterize and to model the extent of FBS magmatism, the distribution of faults and shear zones in the area, to evaluate affinities of the magmatic activity, and the relation between the FBS and the Santa Helena orogen. The geophysical methods identified three anomalies corresponding with FBS outcrops. A fourth anomaly with significantly higher amplitude was observed to the north of the three anomalies. From south to north, the anomalies were named Indiavaí, Azteca, Figueira Branca and Jauru. These anomalies were modeled and indicated a northwest-southeast trend, parallel to regional shear zones. The gamma-ray data enabled the collection of 50 samples from the FBS rocks, the Alto Jauru group that hosts the FBS, from nearby intrusive suites, and the Rio Alegre Terrain. The 30 freshest samples were analyzed by X-ray fluorescence for oxides and some trace elements, 20 by ICP-MS for Rare-Earth Elements and 10 for Nd-Sr isotope analyses. The FBS samples were gabbros and gabbro-norites with Nb/Yb-Th/Yb and TiO2/Yb-Nb/Yb ratios indicating varying degrees of crustal interaction. The TiO2/Yb-Nb/Yb data suggested a subduction related component and the ɛNd-ɛSr indicated a juvenile source. Samples from coeval adjacent intermediate magma suites displayed similar characteristics, which suggest derivation from a bimodal source probably related with the subduction of the Rio Alegre Terrain. We interpreted the tectonic setting of the FBS as a result of a roll-back of the subducted slab, which resulted in rejuvenation of the

  8. Literatura, cinema, parques e produtos: Branca de Neve e suas traduções intersemióticas

    OpenAIRE

    Débora Cibele de Benedetto e Silva

    2014-01-01

    Aproximadamente cem anos após sua primeira publicação em Contos de Fadas para Crianças e Adultos, de Jacob e Wilhelm Grimm, o conto Branca de Neve ganha, em 1937, uma tradução intersemiótica para o cinema produzida pelos estúdios Disney; trata-se da animação Branca de Neve e os Sete Anões, a primeira animação de longa-metragem da história do cinema. O enorme sucesso do filme confere a ele o caráter de uma das versões definitivas do conto original registrado pelos Irmãos Grimm. Além disso, a v...

  9. The complete mitochondrial genome of Bemisia afer (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Wang, Hua-Ling; Xiao, Na; Yang, Jiao; Wang, Xiao-Wei; Colvin, John; Liu, Shu-Sheng

    2016-01-01

    The length of the Bemisia afer (Priesner & Hosny) (Hemiptera: Aleyrodidae) mitochondrial genome (mitogenome) is 14,968 bp and consists of 13 protein coding genes (PCGs), 21 transfer RNAs (tRNA), 2 ribosomal RNAs and 1 control region. Apart from one serine transfer RNA gene (tRNA-Ser) which is absent, the synteny is consistent with the mitogenomes of other whitefly species. The overall base composition of the heavy strand for A, G, T and C is 28.96, 18.97, 36.7 and 15.37%, respectively, with a slight AT bias. Two rare codons (GTG and TTG) are employed as start codons by some PCGs. B. afer is a group of cryptic species. This first mitogenome cloned from African cassava B. afer, therefore, both enrich the whitefly molecular resource and will aid the sequencing of the other species' mitogenomes. It will contribute significantly to resolving the systematics of the B. afer complex.

  10. Resposta de fêmeas de Encarsia formosa Gahan (Hymenoptera: Aphelinidae aos odores do hospedeiro e da planta-hospedeira em olfatômetro de quatro vias Response of female Encarsia formosa Gahan (Hymenoptera: Aphelinidae to host and plant-host odors

    Directory of Open Access Journals (Sweden)

    Kátia Maria Medeiros de Siqueira

    2003-01-01

    Full Text Available A crescente importância da mosca-branca Bemisia tabaci raça B (Hemiptera: Aleyrodidae como praga agrícola tem incentivado a busca de inimigos naturais que possam ser utilizados em programas de controle biológico. Estudou-se a atração de fêmeas de Encarsia formosa (Hymenoptera: Aphelinidae aos odores emanados pelo seu hospedeiro - a mosca-branca B. tabaci raça B - em plantas de tomate, em olfatômetro de quatro vias. O parasitóide não apresentou atração aos odores da planta de tomate nem ao complexo planta de tomate-ninfas de B. tabaci.The increasing importance of the whitefly Bemisia tabaci race B (Hemiptera: Aleyrodidae as one of the major agricultural pest of this century, has resulted in a search for natural enemies that can be used in biological control programs. The response of naive females of Encarsia formosa (Hymenoptera: Aphelinidaeto volatiles from its hostspecies: insect (B. tabacci race B and plant (Lycopersicom esculentum Mill. were tested using 4-nose olfactometre. Parasitoid was not attracted by neither or insect hostspecies volatile.

  11. Controle químico da Cercosporiose, Mancha-Branca e dos Grãos Ardidos em milho

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    André Humberto Brito

    2013-10-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar os efeitos da aplicação de fungicida, no controle da Cercosporiose e da Mancha-Branca do milho, e suas consequências na produtividade de grãos e na incidência de grãos ardidos, além de estabelecer a relação existente entre a produtividade de grãos e a severidade dessas doenças. Dois experimentos distintos (com Azoxystrobina + Cyproconazole e tratamento controle foram conduzidos em três locais, no ano agrícola de 2007/2008. Utilizaram-se 12 híbridos comerciais de milho, que foram avaliados em delineamento de blocos casualizados, com três repetições. Foram realizadas cinco avaliações da severidade das doenças Cercosporiose e Mancha-Branca, por meio de escala de notas, variando de 1 (altamente resistente a 9 (altamente susceptível. Estimou-se a área abaixo da curva de progresso da doença (AACPD. A aplicação de fungicida é eficiente no controle de doenças foliares e na redução da incidência de grãos ardidos, além de proporcionar 12% de aumento na produtividade de grãos, em relação à do tratamento controle. As doenças foliares Cercosporiose e Mancha-Branca reduzem a produtividade de grãos de milho e essa redução é maior quando as doenças ocorrem mais precocemente. A Cercosporiose provoca maior redução na produtividade de grãos, quando comparada com a Mancha-Branca.

  12. Contaminación del agua y distribución de la mosca negra (Diptera: Simuliidae) en el bosque Atlántico, Brasil

    OpenAIRE

    Docile, Tatiana N.; Figueiró, Ronaldo; Gil-Azevedo, Leonardo H.; Nessimian, Jorge L.

    2015-01-01

    Aunque las moscas negras tienen importancia médica debido a que algunas de sus especies son vectores de la Oncocercosis y Mansonelosis, su ecología y su potencial como bioindicadores es aún poco estudiado en la Región Neotropical. En Brasil el uso de bioindicadores se centra principalmente en un índice ecológico multimétrico, en este estudio investigamos la distribución espacial de las moscas negras y su relación con los factores abióticos, para su utilización como indicadores de la integrida...

  13. Primeiro registro da ocorrência de mosca-negra-dos-citros, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Sternorrhyncha: Aleyrodidae) em Roraima.

    OpenAIRE

    Correia, Ruy Guilherme; Lima, Antonio Cesar Silva; Farias,Paulo Roberto Silva; Maciel, Francisco Clemilton da Silva; Silva, Marcos Wanderley da; da Silva, Anderson Gonçalves

    2012-01-01

    A mosca-negra-dos-citros, Aleurocanthus woglumi Ashb, (Hemiptera: Aleyrodidae) é uma importante praga dos citros. De origem asiática, esta praga foi detectada no Brasil pela primeira vez no estado do Pará no ano de 2001. Na cultura dos citros a mosca-negra acarreta danos diretos e indiretos, prejudicando o desenvolvimento e produção das plantas. Além de restringir o comércio de locais de sua ocorrência para áreas livres da presença da praga, visto que o A. woglumi é considerado praga quarente...

  14. White piedra and pediculosis capitis in the same patient Piedra branca e pediculose capitis no mesmo paciente

    Directory of Open Access Journals (Sweden)

    Silvio Alencar Marques

    2012-10-01

    Full Text Available White piedra is a superficial mycosis caused by the genus Trichosporon. It is characterized by nodules on the hair shaft. Pediculosis capitis is caused by Pediculus humanus var. capitis of the suborder Anoplura. Whereas pediculosis is a common infestation, clinical reports of white piedra are rare. Molecular biology procedures identified T. inkin as the agent of white piedra in this case report. The authors present associations between the two diseases in the same patient in order to highlight their clinical differences.Piedra branca é micose superficial causada pelo gênero Trichosporon e caracterizada por nódulos aderidos à haste do pelo. Pediculose capitis é causada pelo Pediculus humanus var. capitis pertencente à subordem Anoplura. Enquanto que a pediculose é enfermidade comum, relatos clínicos de piedra branca são raros. Técnicas de biologia molecular identificaram o agente de piedra branca do presente relato como T.inkin. Os autores apresentam associação de ambas as infestações no mesmo paciente para salientar seus aspectos clínicos distintos.

  15. Impregnação com resina natural na Figueira Branca como forma alternativa de impermeabilização Impregnation with natural resin in the 'Figueira Branca' as alternative form of impermeabilization

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    José de S. Nogueira

    2002-01-01

    Full Text Available Investigou-se, neste trabalho, a capacidade de impregnação da Figueira Branca (Ficus monckii com a resina natural da árvore de Jatobá (Hymenaea courbaril; trata-se de uma espécie de madeira de baixa densidade, originária do Estado do Mato Grosso, Brasil. Foram determinados os coeficientes de retração da madeira, preparando-se posteriormente, a resina, para impregnação, e depois se fez o ensaio inverso do inchamento da madeira impregnada. Compararam-se os dois coeficientes para a madeira não impregnada com o da madeira impregnada, a partir de testes estatísticos com amostras pareadas. O coeficiente de inchamento da madeira impregnada foi significativamente menor que o de retração da não impregnada, em todas as direções dos corpos de prova. Com isto, foi possível se constatar que a impregnação da Figueira Branca com a resina natural do Jatobá tornou-a mais impermeável aumentando, assim, a possibilidade dessa madeira ser empregada na construção civil ou na indústria moveleira.The capacity of impregnation of the 'Figueira Branca' (Ficus monckii, with the natural resin of 'Jatobá' tree (Hymenaea courbaril was investigated in this work. The Figueira Branca is a low density wood from Mato Grosso State, Brazil. The retraction coefficients of the untreated wood were determined and later the resin was prepared for impregnation and the inverse rehearsal of the swelling of the impregnated wood was made. The two coefficients for the impregnated wood and unimpregnated wood were compared by statistical tests of paired samples. The coefficient of swelling of the impregnated wood was significantly smaller than that of retraction of the unimpregnates wood for all directions. Therefore, it was possible to verify that the impregnation of the Figueira Branca, with the natural resin of Jatobá, made it more impermeable, increasing the possibility of its use in the construction of houses or in the furniture industry.

  16. Hongos de importancia agrícola presentes en moscas de la fruta del valle de Ica, Perú

    OpenAIRE

    Carlos E. Tipismana; Lilian R. Astudillo; Juan J. Guillermo

    2013-01-01

    El objetivo del presente trabajo fue aislar e identificar hongos de especímenes de moscas de la fruta de los géneros Ceratitis (Macleay) y Anastrepha (Schiner), del valle de Ica, Perú. Se aislaron hongos pertenecientes a los géneros Alternaria, Aspergillus, Cladosporium, Mucor, Penicillium, Rhizoctonia, Rhizopus y Trichoderma;así como levaduras y micelios estériles. Los recuentos de hongos presentaron rangos entre 8x103 a 8x104 UFC/g para el género Ceratitis; y 7x103 a 7x104 UFC/g para el g...

  17. Results of the radiological survey at 9 Branca Court, Lodi, New Jersey (LJ042)

    Energy Technology Data Exchange (ETDEWEB)

    Foley, R.D.; Floyd, L.M.; Carrier, R.F.

    1989-11-01

    Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. MCW supplied rare earth metals and thorium compounds to the Atomic Energy Commission and various other government agencies from the late 1940s to the mid-1950s. Area residents used the sandlike waste from this thorium extraction process mixed with tea and cocoa leaves as mulch in their yards. Some of these contaminated wastes were also eroded from the site into Lodi Brook. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally {sup 232}Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, 9 Branca Court, Lodi, New Jersey (LJ042), was conducted during 1985 and 1986. 4 refs., 7 figs., 3 tabs.

  18. Biology and management of Bemisia whitefly vectors of cassava virus pandemics in Africa.

    Science.gov (United States)

    Legg, James P; Shirima, Rudolph; Tajebe, Lensa S; Guastella, Devid; Boniface, Simon; Jeremiah, Simon; Nsami, Elibariki; Chikoti, Patrick; Rapisarda, Carmelo

    2014-10-01

    Cassava mosaic disease and cassava brown streak disease are caused by viruses transmitted by Bemisia tabaci and affect approximately half of all cassava plants in Africa, resulting in annual production losses of more than $US 1 billion. A historical and current bias towards virus rather than vector control means that these diseases continue to spread, and high Bemisia populations threaten future virus spread even if the extant strains and species are controlled. Progress has been made in parts of Africa in replicating some of the successes of integrated Bemisia control programmes in the south-western United States. However, these management efforts, which utilise chemical insecticides that conserve the Bemisia natural enemy fauna, are only suitable for commercial agriculture, which presently excludes most cassava cultivation in Africa. Initiatives to strengthen the control of B. tabaci on cassava in Africa need to be aware of this limitation, and to focus primarily on control methods that are cheap, effective, sustainable and readily disseminated, such as host-plant resistance and biological control. A framework based on the application of force multipliers is proposed as a means of prioritising elements of future Bemisia control strategies for cassava in Africa.

  19. Oviposição e dispersão de ninfas de Bemisia tabaci biótipo B em genótipos de tomateiro Oviposition and nymphal dispersion of Bemisia tabaci biotype B on tomato genotypes

    Directory of Open Access Journals (Sweden)

    Marilene Fancelli

    2008-12-01

    Full Text Available Diversos métodos têm sido empregados para avaliar a resistência de plantas a moscas-brancas. Todavia, poucos trabalhos têm sido realizados visando determinar a dispersão de ninfas desses insetos sobre as plantas. O objetivo do presente trabalho foi avaliar a oviposição de B. tabaci biótipo B e a dispersão de suas ninfas em folíolos com e sem exsudatos de genótipos de tomateiro. Foram utilizados sete genótipos de tomateiro: LA716, LA1739, PI134417, LA462, LA1584, 'Santa Clara' e P25 (controle suscetível. A oviposição de B. tabaci biótipo B foi avaliada em gaiolas plásticas (2,8 cm² fixadas na face abaxial dos folíolos, nas quais foram inseridos dez casais do inseto. Para avaliação da dispersão das ninfas, considerou-se o deslocamento dos insetos além do limite da área ocupada pelas gaiolas. As variáveis observadas foram: mortalidade de adultos 24 horas após a liberação, número de ovos, viabilidade da fase de ovo, período de incubação, número de ninfas e dispersão. Em folíolos com exsudato, LA716, LA1739 e PI134417 provocaram as maiores mortalidades. Adultos mortos nos folíolos desses genótipos ficaram aderidos aos tricomas glandulares, o que provocou redução na oviposição do inseto. Para dispersão, nos folíolos com exsudato, os máximos valores ocorreram nos genótipos LA716, LA462 e P25. Na condição sem exsudato, LA716 promoveu a menor dispersão das ninfas. A presença do exsudato influencia negativamente a sobrevivência e oviposição do inseto. A dispersão das ninfas também é afetada pelo exsudato, embora outros fatores possam ser importantes para o deslocamento do inseto.Several methods have been employed for evaluating plant resistance to whiteflies. Although, a few researches have been conducted aiming to determine the whitefly nymphal dispersion on crops. The objective of this work was to evaluate the oviposition of B. tabaci biotype B and nymphal dispersion in leaflets with and without

  20. Ocorrência precoce da mosca das frutas em ameixas Incidence of the southamerican fruit fly on plums

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Salles

    1999-06-01

    Full Text Available O objetivo deste estudo foi verificar qual o estágio fenológico mais precoce da fruta de ameixeira em que ocorreria o ataque de mosca das frutas Anastrepha fraterculus. Os estudos foram conduzidos em plantas adultas de ameixeira, expondo-se fêmeas grávidas da mosca das frutas, confinadas em gaiolas com frutos protegidos do ataque natural. Cinco cultivares de ameixeira foram estudados (Amarelinha, Pluma 7, Reubennel, Santa Rosa e Wade. Essa praga ataca frutos de qualquer um dos cultivares logo nos primeiros estádios do desenvolvimento, quando os mesmos têm somente cerca de 2 a 3cm de diâmetro.The incidence of the southamerican fruit fly, Anastrepha fraterculus, on plum cultivars is reported. The objective of this study was to know the earliest fruit phase that fly attack could occur. Fertilized females were confined with fruits in plum trees in an orchard. Five plums cultivars were studied: Amarelinha; Pluma 7; Reubennel; Santa Rosa and Wade. This pest attack fruits during first stages of their development, mainly they have only from 2 to 3 centimeters of diameter.

  1. Politicamente correta rosa branca: intertexto e enunciação

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    Ana Cristina Fricke Matte

    2004-07-01

    Full Text Available

    A intertextualidade é uma noção pouco óbvia em semiótica. Embora o assunto seja tratado, em geral, com uma certa dose de interdisciplinaridade, este trabalho procura explorar as premissas da teoria a fim de realizar uma análise semiótica da intertextualidade, stricto sensu. Nossa abordagem vai privilegiar a apresentação e a aplicação de conceitos como texto, intertexto, pistas e tipos de contexto: situacional, interno e externo. Longe de pretender esgotar a questão, este trabalho introduz o assunto procurando indicar os limiares e sua potencialidade no âmbito da teoria. Para fins de ilustração, apresentamos as análises de dois textos: a letra de uma canção infantil cujo texto verbal, bastante sucinto, termina com reticências (Rosa Branca foi ao chão, gravada pelo grupo vocal MPB4, e a introdução à versão brasileira do livro Contos de Fadas politicamente corretos, de James Finn Garner. A canção explora a relação lingüística entre o adulto e a criança, na dimensão enunciativa, enquanto o livro de contos explora a identidade do iluminismo com o politicamente correto, numa visão crítica bem-humorada.

  2. Plastic cup traps equipped with light-emitting diodes for monitoring adult Bemisia tabaci (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Chu, Chang-Chi; Jackson, Charles G; Alexander, Patrick J; Karut, Kamil; Henneberry, Thomas J

    2003-06-01

    Equipping the standard plastic cup trap, also known as the CC trap, with lime-green light-emitting diodes (LED-plastic cup trap) increased its efficacy for catching Bemisia tabaci by 100%. Few Eretmocerus eremicus Rose and Zolnerowich and Encarsia formosa Gahan were caught in LED-plastic cup traps. The LED-plastic cup traps are less expensive than yellow sticky card traps for monitoring adult whiteflies in greenhouse crop production systems and are more compatible with whitefly parasitoids releases for Bemisia nymph control.

  3. Rickettsia influences thermotolerance in the whitefly Bemisia tabaci B biotype

    Institute of Scientific and Technical Information of China (English)

    Marina Brumin; Svetlana Kontsedalov; Murad Ghanim

    2011-01-01

    The whitefly Bemisia tabaci harbors Portiera aleyrodidarum,an obligatory symbiotic bacterium,as well as several secondary symbionts,including Rickettsia,Hamiltonella,Wolbachia,Arsenophonus,Cardinium and Fritschea,the function of which is unknown.In Israel,Rickettsia is found in both the B and Q of B.tabaci biotypes,and while all other secondary symbionts are located in the bacteriomes,Rickettsia can occupy most of the body cavity of the insect.We tested whether Rickettsia influences the biology of B.tabaci and found that exposing a Rickettsia-containing population to increasing temperatures significantly increases its tolerance to heat shock that reached 40℃,compared to a Rickettsia-free population.This increase in tolerance to heat shock was not associated with specific induction of heat-shock protein gene expression; however,it was associated with eduction in Rickettsia numbers as was assessed by quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analyses.To assess the causes for thermotolerance when ickettsia is reduced,we tested whether its presence is associated with the induction of genes required for thermotolerance.We found that under normal 25℃ rearing temperature,genes associated with response to stress such as cytoskeleton genes are induced in the Rickettsia-containing population.Thus,the presence of Rickettsia in B.tabaci under normal conditions induces the expression of genes required for thermotolerance that under high temperatures indirectly lead to this tolerance.

  4. Tendências da desigualdade salarial para coortes de mulheres brancas e negras no Brasil

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    Ana Maria Hermeto Camilo de Oliveira

    2006-06-01

    Full Text Available É feita uma análise das tendências da desigualdade salarial da força de trabalho feminina no Brasil, segundo a raça, durante as décadas de 1980 e 1990. Crescentes retornos de qualificação e crescente demanda por trabalho qualificado resultam em uma divergência do crescimento salarial entre os trabalhadores com alta e baixa qualificação. Este crescente hiato resulta em um aumento da desigualdade salarial por raça. Com o propósito de interpretar as tendências, são examinadas diferenças por raça nos padrões de casamento, fecundidade, arranjos domiciliares, níveis educacionais, participação na força de trabalho, níveis de qualificação, alocação ocupacional e salários, distinguindo entre medidas de período e coorte. São usados dados provenientes das PNADs 1987-1999 para analisar a importância de mudanças inter e intracoortes para mulheres brancas e negras. Funções salariais são estimadas a partir dos dados agregados da série temporal de cross sections, usando mínimos quadrados ordinários e regressões quantílicas.We analyze trends of wage inequality of the Brazilian female labor force, by race, during the 1980s and 1990s. Increasing returns to skills and increasing demand for skilled labor result in a divergence of wages growth between high and low skilled workers. This increasing gap results in an increase of wage inequality by race. In order to interpret trends, we take into account race differences in marriage patterns, fertility, household arrangements, educational levels, labor market participation, skill levels, occupational location and earnings, distinguishing between period and cohort measures. We use 1987-1999 Brazilian Household Sample Surveys data to examine the importance of within- and between-cohort changes for black and white women. Earnings functions are estimated from the pooled time-series of these cross-section data, using OLS and quantile regressions.

  5. Parasitismo natural em moscas-das-frutas (Diptera: Tephritidae no semiárido do sudoeste da Bahia, Brasil

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    Ricardo Falcão de Sá

    2012-12-01

    Full Text Available Parasitoides são importantes agentes de controle natural de tefritídeos, e os conhecimentos sobre as relações tritróficas podem subsidiar o manejo destas pragas. Este trabalho objetivou estimar índices de parasitismo em moscas-das-frutas, em 21 espécies vegetais, e identificar as espécies de parasitoides associados, nas condições do semiárido do sudoeste da Bahia. Oito hospedeiros apresentaram infestação por Anastrepha spp. e, destes, em quatro, ocorreu parasitismo superior a 20,0%, sendo: 20,8% (Ziziphus joazeiro L.; 21,3% (Spondias tuberosa L.; 32,4% (Spondias purpurea L. e 57,1% (Malpighia emarginata L.. Os parasitoides coletados pertencem à família Braconidae, sendo 89% de Doryctobracon areolatus e 11% de Asobara anastrephae.

  6. Public management of urban hospitality: a case study of Agua Branca Park, São Paulo city

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    Luciana Carla Sagi

    2008-10-01

    Full Text Available This article is a qualitative study about the public management of Água Branca Park in São Paulo city and its impacts on the hospitality of this area. The research began in 2005 in master's degree in Hospitality at Anhembi Morumbi University and was pursuing independent until 2008. It is examined the three major dimensions of management: administrative and institutional, socio-political and economic-financial. It was possible to see how aspects related to human resources training, political projects of greater magnitude, physical resources, planning systematic and relationships with the various social actors ultimately result in the hospitality that the park offers to its visitors. Água Branca Park is having a good performance in that sense, since the various components of public management appear to be moving towards the park to be an area full of leisure, which includes the 3 D's of Dumazedier (1980: rest, fun and development, minimizing the pressures that affect Sao Paulo metropolis.

  7. "Cricket singing means rain": semiotic meaning of insects in the district of Pedra Branca, Bahia State, northeastern Brazil.

    Science.gov (United States)

    Costa Neto, Eraldo M

    2006-03-01

    This paper deals with the semiotic meanings which are given both to the appearance and/or behavior of insect species according to the ethnoentomological knowledge of the inhabitants of the village of Pedra Branca, Bahia State, Brazil. Data were collected from February to May 2001 by performing open-ended, recorded interviews with nine men and twenty-five women, whose ages ranged from 19 to 82 years old. Data were analyzed by using the union model, which involves considering all available information on the surveyed subject. Twelve kinds of insects were associated with both beneficial and harmful events, as well as with the indication of changing weather. The way local people perceive and interpret the appearance and/or behavior of certain species of insects depends on the cultural background of each inhabitant. The following semiotic meanings were recorded: fatal, funereal, auspicial, meteorological, societal, monetary, and of abundance or scarcity. The beliefs in the augural power of insects in the village of Pedra Branca are deep-rooted in the local tradition and are transmitted from generation to generation through oral culture. It is hoped that the data now available will be incorporated into a curriculum by those researchers interested in insect conservation and ethnobiology as well.

  8. PLANO DE MARKETING PARA A ASSOCIAÇÃO CRIANÇAS ESPECIAIS DE SANTA BRANCA ANTONIO NARVAES - (CESB

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    Nayara Cristini Rodrigues

    2017-01-01

    Full Text Available O Plano de Marketing pode ser entendido como um documento a qual estão detalhadas as ações necessárias para se atingir um ou mais objetivos na área do marketing. O propósito deste trabalho é elaborar um projeto para a Associação Crianças Especial de Santa Branca (CESB, a fim de desenvolver uma comunicação adequada, por meio de estratégias e procedimentos que caracterizam a divulgação, para que a entidade seja capaz de informar as necessidades para o público alvo e assim, consequentemente, desenvolver soluções pertinentes, para que esta alcance seus objetivos referente a oferecer atendimento clínico, incluindo práticas educativas. A partir disso, foi realizada uma pesquisa de campo nos municípios de Santa Branca/SP, Jacareí/SP e São José dos Campos/SP, onde ressaltou-se uma deficiência em relação à divulgação, gerando uma dificuldade de arrecadação para a associação, tanto de voluntariado como de verba financeira.

  9. Pathogenicity of Aschersonia spp. against whiteflies Bemisia argentifolii and Trialeurodes vaporariorum

    NARCIS (Netherlands)

    Meekes, E.T.M.; Fransen, J.J.; Lenteren, van J.C.

    2002-01-01

    Entomopathogenic fungi of the genus Aschersonia are specific for whitefly and scale insects. They can be used as biological control agents against silverleaf whitefly, Bemisia argentifolii and greenhouse whitefly, Trialeurodes vaporariorum. Forty-four isolates of Aschersonia spp. were tested for the

  10. Aerial electrostatic-charged spray for deposition and efficacy against sweetpotato whitefly (Bemisia tabaci) on cotton

    Science.gov (United States)

    Efficacy of aerial electrostatic-charged sprays was evaluated for spray deposit characteristics and season-long control of sweet potato whitefly (SWF), Bemisia tabaci biotype B (a.k.a. B. argentifolii), in an irrigated 24-ha cotton field. Treatments included electrostatic-charged sprays at full and ...

  11. Pathogenicity of Aschersonia spp. against whiteflies Bemisia argentifolii and Trialeurodes vaporariorum

    NARCIS (Netherlands)

    Meekes, E.T.M.; Fransen, J.J.; Lenteren, van J.C.

    2002-01-01

    Entomopathogenic fungi of the genus Aschersonia are specific for whitefly and scale insects. They can be used as biological control agents against silverleaf whitefly, Bemisia argentifolii and greenhouse whitefly, Trialeurodes vaporariorum. Forty-four isolates of Aschersonia spp. were tested for

  12. Quantitative resistance against Bemisia tabaci in Solanum pennellii : Genetics and metabolomics

    NARCIS (Netherlands)

    van den Oever-van den Elsen, Floor; Lucatti, Alejandro F.; van Heusden, Sjaak; Broekgaarden, Colette|info:eu-repo/dai/nl/314605894; Mumm, Roland; Dicke, Marcel; Vosman, Ben

    2016-01-01

    The whitefly Bemisia tabaci is a serious threat in tomato cultivation worldwide as all varieties grown today are highly susceptible to this devastating herbivorous insect. Many accessions of the tomato wild relative Solanum pennellii show a high resistance towards B. tabaci. A mapping approach was

  13. Effect of soil application of cyantraniliprole on Bemisia tabaci (MED whitefly) and Amblyseius swirskii, 2016

    Science.gov (United States)

    Bemisia tabaci is a polyphagous pest known to feed upon over 900 plant taxa, and is an effective vector of more than 100 plant damaging viruses. Among different biotypes of this cryptic species complex, MEAM1 and MED whitefly are the two most destructive members posing threats of several crops of ec...

  14. Effect of dinotefuran on Bemisia tabaci (MED whitefly) and Amblyseius swirskii, 2016

    Science.gov (United States)

    Bemisia tabaci is a polyphagous pest known to feed upon over 900 plant taxa, and is an effective vector of more than 100 plant damaging viruses. Among different biotypes of this cryptic species complex, MEAM1 and MED whitefly are the two most destructive members posing threats of several crops of ec...

  15. Quantitative resistance against Bemisia tabaci in Solanum pennellii : Genetics and metabolomics

    NARCIS (Netherlands)

    van den Oever-van den Elsen, Floor; Lucatti, Alejandro F.; van Heusden, Sjaak; Broekgaarden, Colette; Mumm, Roland; Dicke, Marcel; Vosman, Ben

    2016-01-01

    The whitefly Bemisia tabaci is a serious threat in tomato cultivation worldwide as all varieties grown today are highly susceptible to this devastating herbivorous insect. Many accessions of the tomato wild relative Solanum pennellii show a high resistance towards B. tabaci. A mapping approach was u

  16. Molecular and functional characterization of Bemisia tabaci aquaporins reveals the water channel diversity of hemipteran insects

    Science.gov (United States)

    The Middle East-Asia Minor 1 (MEAM1) whitefly, Bemisia tabaci (Gennadius) is an economically important pest of food, fiber, and ornamental crops. This pest has evolved a number of adaptations to overcome physiological challenges, including 1) the ability to regulate osmotic stress between gut lumen ...

  17. Insecticidal Activity of Some Reducing Sugars Against the Sweet Potato Whitefly, Bemisia tabaci, Biotype B

    Science.gov (United States)

    The effects of 15 sugars on sweet potato whitefly (Bemisia tabaci) survival were determined using bioassays. Arabinose, mannose, ribose and xylose were strongly inhibitory to both nymphal and adult survival. When 10% mannose was added to the diet, 10.5%, 1.0% and 0% of nymphs developed to the 2nd, ...

  18. Insecticidal Activity of Chromobacterium subtsugae on the Sweet Potato Whitefly, Bemisia tabaci, Biotype B

    Science.gov (United States)

    Chromobacterium subtsugae crude extracts contain compounds that are toxic to nymphal and adult Bemisia tabaci. When fed on artificial diet containing 10% of the supernatant of an aqueous cell-free extract of C subtsugae, the number of 2nd and 4th instar nymphs and of emerged adults was significantl...

  19. Del ciudadano capacitario de sieyès a las clases polítcas de Mosca

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    Maria Elena Ludeña Párján

    2006-01-01

    Full Text Available En el presente artículo se trata de revisar las diferentes concepciones de clase política planteadas en el trabajo de Gaetano Mosca, y la concepción de ciudadano capacitario de Emmanuel Sieyès, basándonos en la idea fundamental que ese ciudadano capacitario que plantea Sieyès será la base para la formación de clases políticas en las sociedades modernas. El objetivo general que nos planteamos para este trabajo es estudiar, a la luz de la teoría de las clases políticas si la proposición de ciudadano capacitario que plantea Sieyés nos conduce hacia el establecimiento de clases políticas dentro de la sociedad. La metodología en la que basaremos nuestra investigación es fundamentalmente el análisis de textos principales, para su posterior comparación. Abstract This article aims to review the different concepts of political class proposed by Gaetano Mosca and the concept of active citizen developed by Emmanuel Sieyès. Our starting point is the idea that this active citizen will be the basis to shape the political class formation in the modern societies. The main objective of this work is to verify, in the light of the political class theory, if the concept of active citizen proposed by Sieyès leads us to the establishment of the political classes in the society. The methodology applied in this work is the analisis of primary texts for purposes of comparison.

  20. Molecular Characterization of Vitellogenin and Vitellogenin Receptor of Bemisia tabaci.

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    Santosh Kumar Upadhyay

    Full Text Available Vitellogenin (Vg plays vital role in oocytes and embryo development in insects. Vg is synthesized in the fat body, moves through haemolymph and accumulates in oocytes. Vitellogenin receptors (VgR present on the surface of oocytes, are responsible for Vg transportation from haemolymph to oocytes. Here, we cloned and characterized these genes from Bemisia tabaci Asia1 (BtA1 species. The cloned BtA1Vg and BtA1VgR genes consisted of 6,330 and 5,430 bp long open reading frames, which encoded 2,109 and 1,809 amino acid (AA residues long protein. The BtA1Vg protein comprised LPD_N, DUF1943 and VWFD domains, typical R/KXXR/K, DGXR and GL/ICG motifs, and polyserine tracts. BtA1VgR protein contained 12 LDLa, 10 LDLb and 7 EGF domains, and a trans-membrane and cytoplasmic region at C-terminus. Phylogenetic analyses indicated evolutionary association of BtA1Vg and BtA1VgR with the homologous proteins from various insect species. Silencing of BtA1VgR by siRNA did not affect the transcript level of BtA1Vg. However, BtA1Vg protein accumulation in oocytes was directly influenced with the expression level of BtA1VgR. Further, BtA1VgR silencing caused significant mortality and reduced fecundity in adult whiteflies. The results established the role of BtA1VgR in transportation of BtA1Vg in oocytes. Further, these proteins are essential for fecundity, and therefore these can be potential RNAi targets for insect control in crop plants.

  1. Compatibility of the insect pathogenic fungus Beauveria bassiana with neem against sweetpotato whitefly, Bemisia tabaci, on eggplant

    Science.gov (United States)

    A study on the compatibility of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) with neem was conducted against sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on eggplant. Initially, three concentrations of B. bassiana (106, 1...

  2. New records of entomopathogenic fungi infecting Bemisia tabaci and Trialeurodes vaporariorum, pests of horticultural crops, in Argentina

    Science.gov (United States)

    The whiteflies (Hemiptera: Aleyrodidae) Bemisia tabaci (Gennadius), and Trialeurodes vaporariorum (Westwood) are major crop pests throughout the world. Although extensive research about biological control of whitefly has been conducted towards these insect's parasitoids and predators, several entom...

  3. Comparison of three trap types for adult catching of whitefly Bemisia tabaci and its parasitoid Eretmocerus mundus in tomato greenhouse

    OpenAIRE

    Nombela, Gloria; Chu, CC.; Heneberry, T.; Muñiz, M.

    2003-01-01

    The attractiveness of three trap types to Bemisia tabaci (Gennadius) B-biotype (= Bemisia argentifolii Bellows & Perring) and Eretmocerus mundus Mercet adult was compared in two choice experiments in a greenhouse at the Centro de Ciencias Medioambientales, Madrid, Spain.  Yellow sticky cards equipped with light-emitting-diodes (LED-YC) caught more adults per trap per day than yellow sticky card (YC) traps.YC traps caught significantly more B. tabaci and E. mundus adults than plastic cup traps...

  4. Mosca-dos-chifres, Haematobia irritans: comportamento e danos em vacas e bezerros Nelore antes da desmama The hornfly, Haematobia irritans: behaviour and damage caused in Nellore cows and pre-weaning calves

    Directory of Open Access Journals (Sweden)

    Ivo Bianchin

    2002-09-01

    Full Text Available Estudaram-se o comportamentos e os danos causados pela mosca-dos-chifres em vacas e bezerros Nelore antes da desmama. Foram utilizados dois grupos de 60 animais cada um, sendo um grupo com infestação natural de moscas e o outro sem moscas, por quatro anos consecutivos. Observou-se que o número de moscas das vacas não ultrapassou a média de 80 moscas/animal, em todos os anos experimentais. A maioria das vacas (83% apresentou poucas moscas, enquanto a minoria (17% teve maior quantidade. Os bezerros foram pouco infestados pelas moscas. Chuvas acima de 100 mm em curto espaço de tempo diminuíram a infestação de moscas. O ganho de peso das vacas tratadas com inseticida (sem infestação por moscas bem como os seus bezerros foi maior do que as vacas controle, porém não foi estatisticamente significativo (P>0,05. A percentagem média de prenhez, nos quatro anos, das vacas tratadas foi 15% superior a das não tratadas e esta diferença foi causada provavelmente pela infestação de moscas nos touros.The hornfly and losses caused by it in Nellore cows and pre-weaning calves where studied, using two groups of 60 animals each, one group with a natural infestation and the other without hornfly, during four consecutive years. It was seen that the number of flies on the cows did not exceed an average of 80 flies/animal in all years of observation. The majority of the cows (83% had few flies, whereas 17% had larger numbers. The calves were infested with few flies. Rainfall in excess of 100 mm during short periods diminished fly infestation. Weight gain in the cows without flies (treated with insecticides as well as their calves was greater than in the control cows, but not statistically significant (P>0.05. Mean percentage pregnancy during the four years was 15% more in treated cows than the non-treated animals, and this difference was probably due to the infestation of the bulls.

  5. Contribución al Conocimiento de las Moscas de las Frutas (Tephritidae y sus Parasitoides en el Departamento de Antioquia

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    Yepes R. Francisco

    1989-12-01

    Full Text Available Las moscas de las frutas constituyen, como grupo, la plaga insectil mas importante de estos cultivos en Colombia y en el mundo. Además de Anastrepha spp., la especie más dañina dentro de las verdaderas moscas de las frutas (Tephritidae, la mosca del Mediterráneo, fue detectada por primera vez en Colombia en 1986 y confirmada su presencia en Antioquia en abril de 1987. El trabajo se realizó en tres fases simultáneamente; una de campo (11 regiones, otra de laboratorio (procesamiento de muestras y la tercera consistió en la obtención de la identificación de las especies (moscas y parasitoides Los resultados fueron: 1.la especie más distribuida y frecuentemente registrada en mayor número de hospedantes fue Anastrepha striata; fue reportada por primera vez en guayabo anselmo (Campomanesia cornifolia y guayabo de mono (Bellucia axinanthera, 2.la especie que ataca a B. axinanthera en el nordeste y oriente antioqueños es A sp. "F-]", aparentemente no descrita y considerada dentro de un grupo actualmente bajo revisión, 3.en total se encontraron 13 especies diferentes de Tephritidae (incluyendo los géneros de Anastrepha, Ceratitis y Toxotrypana y siete especies de Lonchaeidae (Neosilba spp. y Dasiops spp., 4.dentro de los parasitoides de larva-pupa de Anastrepha spp. se destacan: Doryctobracon areolatus y D. crawfordi¡ Opius anastrephae, Asobara anastrephaey Microcrasis sp. pertenecientes a la familia Braconidae y Aganaspis pelleranoi (Eucoilidae y Aceratoneuromyia indicum (Eulophidae.

  6. Levantamento de moscas-das-frutas e seus parasitoides em citros, no município de Viçosa, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Daniel Lucas Magalhães Machado

    2012-12-01

    Full Text Available As moscas-das-frutas são responsáveis por grandes perdas em fruteiras comerciais no Brasil, por isso é fundamental conhecer as espécies predominantes na região. Objetivou-se com este trabalho estudar a ocorrência de moscas-das-frutas (Diptera: Tephritidae e seus parasitoides em laranjas doces (Citrus sinensis L. Osbeck, tangerina Poncã (Citrus reticulata Blanco e mexerica Rio (Citrus deliciosa Ten, no município de Viçosa, Minas Gerais. Os frutos foram coletados em abril de 2008. No laboratório eles foram acondicionados em caixas plásticas contendo areia umedecida e em ambiente controlado para obtenção dos pupários, que foram contados, acondicionados em frascos de vidro com areia fina e mantidos em estufa até a emergência dos adultos. Somente uma espécie de mosca-das-frutas (Anastrepha fraterculus (Wiedemann, 1830 e uma de parasitoide (Doryctobracon brasiliensis Szépligeti foram identificadas. Dentre as variedades, a laranja doce Baianinha apresentou o maior índice de infestação, e os menores foram atribuídos à mexerica Rio e à tangerina Poncã.

  7. Genetic diversity of Salminus brasiliensis wild populations in downstream and upstream Cachoeira Branca, Verde River MS Brazil: a preliminary view

    OpenAIRE

    Ricardo Pereira Ribeiro; Nelson Mauricio Lopera-Barrero; Jayme Aparecido Povh; Maria del Pilar Rodriguez-Rodriguez; Darci Carlos Fornari; Gilmar Baumgartner; Dirceu Baumgartner; Felipe Pinheiro de Souza; Pedro Luiz de Castro; Angela Rocio Poveda-Parra

    2016-01-01

    As usinas hidrelétricas são responsáveis por gerar a maioria da energia elétrica utilizada no Brasil, entretanto, suas construções podem gerar entraves ambientais, entre eles a interrupção da migração de peixes. O presente estudo foi realizado no período anterior a construção da UHE São Domingos sobre o eixo da cachoeira Branca, no rio Verde – Mato Grosso do Sul (Brazil), e teve como objetivo avaliar a diversidade genética de duas populações naturais de dourado (Salminus brasiliensis) localiz...

  8. IRRADIAÇÃO UV-C EM CULTIVARES DE UVAS NIÁGARA BRANCA, TREBBIANO, ISABEL E CABERNET SAUVIGNON

    OpenAIRE

    Taísa Ceratti Treptow

    2012-01-01

    Este trabalho avaliou a irradiação UV-C em tecidos vegetais de ráquis com e sem bagas, e bagas com pedúnculo de Vitis vinifera e Vitis labrusca. Nas bagas da cv. Isabel, foram analisados os compostos voláteis nos dias 2, 5 e 10 de armazenamento a 20 C e sobre o efeito da irradiação UV-C no 5 dia de armazenamento. Os experimentos basearam-se em quatro tratamentos de irradiação UV-C (0, 1, 2 e 3 kJ m-2), com quatro cv. (Niágara branca, Trebbiano, Isabel e Cabernet sauvignon) e tempos de avaliaç...

  9. IRRADIAÇÃO UV-C EM CULTIVARES DE UVAS NIÁGARA BRANCA, TREBBIANO, ISABEL E CABERNET SAUVIGNON

    OpenAIRE

    Taísa Ceratti Treptow

    2012-01-01

    Este trabalho avaliou a irradiação UV-C em tecidos vegetais de ráquis com e sem bagas, e bagas com pedúnculo de Vitis vinifera e Vitis labrusca. Nas bagas da cv. Isabel, foram analisados os compostos voláteis nos dias 2, 5 e 10 de armazenamento a 20 C e sobre o efeito da irradiação UV-C no 5 dia de armazenamento. Os experimentos basearam-se em quatro tratamentos de irradiação UV-C (0, 1, 2 e 3 kJ m-2), com quatro cv. (Niágara branca, Trebbiano, Isabel e Cabernet sauvignon) e tempos de avaliaç...

  10. Redução do acamamento em aveia-branca com uso do regulador de crescimento etil-trinexapac

    Directory of Open Access Journals (Sweden)

    Maraisa Crestani Hawerroth

    2015-02-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da aplicação de concentrações do regulador de crescimento etil-trinexapac na altura de planta, no acamamento e na produtividade de grãos da cultivar de aveia-branca Barbarasul, em diferentes ambientes de cultivo e doses de nitrogênio. Os experimentos foram conduzidos nas safras 2010 e 2011 nos municípios de Capão do Leão e Augusto Pestana, no Estado do Rio Grande do Sul, e nas safras 2010 e 2012 no Município de Lages, no Estado de Santa Catarina. Utilizou-se o delineamento de blocos ao acaso, em arranjo fatorial 4x2x6 (dose de etil-trinexapac, estádio de desenvolvimento da planta e ambiente, com quatro repetições constituídas por parcelas úteis de 3,0 m2. Em cada ambiente, realizou-se adubação nitrogenada com 30 e 90 kg ha-1 de N. Foram avaliados os caracteres altura de planta, percentagem de acamamento e produtividade de grãos. A aplicação do regulador de crescimento etil-trinexapac nas doses de 100 a 150 g i.a. ha-1 em plantas de aveia-branca 'Barbarasul', nos estádios E31 e E32, reduz a altura das plantas e a percentagem de acamamento, sem prejuízos à produtividade de grãos. A intensidade da redução do acamamento depende das características do ambiente de cultivo.

  11. Danos de moscas-das-frutas (Diptera, Tephritidae em citros, manejados no sistema orgânico de produção

    Directory of Open Access Journals (Sweden)

    Fernando Felisberto da Silva

    2014-10-01

    Full Text Available As moscas-das-frutas são as principais pragas da fruticultura mundial. Consideradas chaves para a produção de citros, torna-se necessário o seu monitoramento, visando a evitar os danos diretos. O experimento teve como objetivos conhecer a variação populacional de Anastrepha fraterculus e a relação de sua população com danos em pomares orgânicos de Citrus sinensis, cultivar Céu e de C. sinensis x Citrus reticulata tangor 'Murcott'. Os dados foram coletados em 2003 e 2004 durante o período de maturação dos frutos, na região do vale do Caí, RS, Brasil. O número de moscas-das-frutas foi registrado, semanalmente, por meio de armadilhas McPhail, contendo suco de uva, a 25%. Danos aos frutos foram determinados pela razão entre frutos sadios e frutos danificados pela mosca. Registros meteorológicos de temperatura, umidade relativa e precipitação pluviométrica foram obtidos, em estação meteorológica distante 30 km das áreas experimentais. Verificou-se que, em condições ideais de precipitação pluvial, maiores foram as populações de A. fraterculus, espécie predominante na região. A população estimada capaz de causar danos aos frutos variou de acordo com o cultivar, sendo a laranjeira 'Céu' a mais susceptível. Os maiores picos populacionais ocorrem na fase de mudança de coloração dos frutos. Porém, na fase de maturação, as moscas causaram os maiores danos, dada a intolerância dos frutos ao ataque. Conclui-se que a infestação dos frutos de citros por A. fraterculus está relacionada com espécie e cultivar e com fatores climáticos, principalmente com a precipitação pluvial. O monitoramento constante da população de mosca-das-frutas é importante na determinação da infestação na colheita.

  12. DEZ ANOS DE PESQUISAS SOBRE MOSCAS-DAS-FRUTAS (DIPTERA: TEPHRITIDAE NO ESTADO DO AMAPÁ: AVANÇOS OBTIDOS E DESAFIOS FUTUROS.

    Directory of Open Access Journals (Sweden)

    Ezequiel da Glória de Deus

    2013-12-01

    Full Text Available As moscas-das-frutas (Diptera: Tephritidae estão entre as principais pragas da agricultura mundial, sendo motivo de preocupação especialmente para países tropicais em desenvolvimento, os quais têm na fruticultura um importante componente de sua balança comercial. Esta revisão tem por objetivo compilar informações geradas nos últimos 10 anos sobre moscas-das-frutasno estado do Amapá, com ênfase em distribuição, hospedeiros e parasitoides. Além disso, visa indicar as prioridades de pesquisa para os próximos anos.No estado do Amapá, os estudos com moscas-das-frutas e seus inimigos naturais apresentaram, nos últimos anos, significativo crescimento. Atualmente, além Bactrocera carambolae, estão assinaladas para o Estado 34 espécies de Anastrepha. Anastrepha distincta, Anastrepha coronilli, Anastrepha fraterculus e Anastrepha striata são as espécies mais amplamente distribuídas. Estão assinaladas para o estado 37 espécies vegetais hospedeiras (pertencentes a 19 famílias botânicas de moscas-das-frutas. Anastrepha striata é espécie mais polífaga, estando associada a 25 hospedeiros. Nove espécies de parasitoides específicos de moscas-das-frutas estão registrados, sendo Doryctobracon areolatuso mais abundante. Apesar do significativo avanço, novos estudos sobre biologia, genética, ecologia, distribuição e dispersão populacional, bem como fatores reguladores dos níveis populacionais são necessários, com vista a desenvolver estratégias de controle menos onerosas com efeitos não nocivos ao ambiente. Palavras-chave: Anastrepha, Bactrocera carambolae, parasitoides, Amazônia. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v3n3p157-168

  13. Abordagem do paciente ferido por arma branca na zona de Ziedler

    Directory of Open Access Journals (Sweden)

    Decio Luis Portella

    2016-10-01

    Full Text Available Introdução: Ferimentos cardíacos penetrantes já foram considerados letais e intratáveis. Homero fez a primeira descrição da morte de Sarpedon em A Ilíada, em 3000 a.C. Em 1883, Billroth afirmou em um Congresso Europeu de Cirurgia que "o cirurgião que tentar suturar um ferimento cardíaco deverá perder o respeito de seus colegas". Em 1897, Rehn apresentou o primeiro caso bem sucedido de cardiorrafia de ventrículo direito Cerca de 87% das lesões cardiovasculares são, em particular, oriundas de trauma penetrante. E, as lesões ventriculares são mais frequentes que as atriais Objetivo: Descrever a abordagem realizada no serviço para pacientes com ferimento por arma branca (FAB na zona de Ziedler, através da experiência de sete casos relatados em 7 anos Discutir a relevância da utilização do FAST (Focused Assesment with Sonography for Trauma na avaliação primária do protocolo ATLS (Advanced Trauma Life Support e a sequência de reavaliação, e analisar qual o melhor procedimento diagnóstico e terapêutico para cada apresentação clínica do paciente. Método: Realizou-se um estudo retrospectivo, descritivo e analítico de sete pacientes atendidos no pronto atendimento do Politrauma do Conjunto Hospitalar de Sorocaba. O conteúdo deste trabalho foi obtido através da revisão de prontuário e descrição cirúrgica, registro fotográficos, além de revisão da literatura. Resultados: A experiência do serviço mostra que a abordagem inicial descrita pelo ATLS é fundamental para guiar o atendimento ao ferido. Quando da realização do FAST na avaliação primária indicando ausência de líquido na janela pericárdica deve-se manter o paciente com FAB em zona de Ziedler na sala de urgência sendo assistido por profissionais capacitados. A necessidade de Tomografia Computadorizada com contraste demonstra-se relevante para os casos em que há FAST inconclusivo, ainda que com paciente estável. A amostra exibe um caso de

  14. Special Issue Introduction- The Whitefly Bemisia tabaci Species Complex and Begomoviruses: Research Progress and Future Prospects

    Institute of Scientific and Technical Information of China (English)

    LIU Shu-sheng; Linda L Walling; WANG Xiao-wei

    2012-01-01

    The whitefly Bemisia tabaci species complex and the begomoviruses they transmit are devastating agricultural pests worldwide.With the rapid and further invasions by some members of the whitefly species complex into new regions,their impacts on human society are likely to increase in the years to come.This special issue of the Journal of Integrative Agriculture is devoted to these two groups of interacting organisms.The initial inspiration for this special issue came from the International Symposium on Future Directions in Bemisia Research held in Hangzhou,China,in October 2010.The symposium was organized by the Institute of Insect Sciences and the Institute of Biotechnology of Zhejiang University,China,in an effort to promote information exchange and international collaborative research on a few key aspects of the biology of B.tabaci.

  15. Foraging behavior and prey interactions by a guild of predators on various lifestages of Bemisia tabaci

    OpenAIRE

    Hagler, James R.; Charles G. Jackson; Rufus Isaacs; Machtley, Scott A.

    2004-01-01

    The sweetpotato whitefly, Bemisia tabaci (Gennadius) is fed on by a wide variety of generalist predators, but there is little information on these predator-prey interactions. A laboratory investigation was conducted to quantify the foraging behavior of the adults of five common whitefly predators presented with a surfeit of whitefly eggs, nymphs, and adults. The beetles, Hippodamia convergens Guérin-Méneville and Collops vittatus (Say) fed mostly on whitefly eggs, but readily and rapidly prey...

  16. Development and reproduction of Bemisia tabaci (Homoptera: Aleyrodidae) on three bean species

    Institute of Scientific and Technical Information of China (English)

    PETERD.MUSA; SHUN-XIANGREN

    2005-01-01

    The development, survivorship and reproduction of Bemisia tabaci B-biotype on three bean species were studied at 26 ± 1 ℃ in the laboratory. The developmental periods from egg to adult varied from 27.80 days on garden beans to 18.20 days on soybeans. The survivorship from egg to adult on soybeans, cowpeas and garden beans was 77.14, 70.14 and 64.28%, respectively. The average longevity of female adults ranged from 12.30 days on soybeans to 9.80 days on garden beans, and the oviposition of B. tabaci varied from 160.85 eggs on soybeans to 98.00 eggs on garden beans. Life table parameters were calculated as biological attributes for Bemisia tabaci populations fed on three bean species. The results indicated that the intrinsic rate of increase (rm), the finite rate of increase ( λ ) and net reproductive rate (R0) were high for populations fed on soybeans, with values of 0.1857,1.2041 and 82.1576, respectively. The corresponding values were less for populations fed on garden beans, with values of 0.1097, 1.1159 and 31.2661, respectively. The parametric values for cowpeas were intermediate between soybeans and garden beans but no significant difference were observed for the rm values for soybeans and cowpeas. Experimental evidence in our investigation indicated that Bemisia tabaci is best adapted and shows the greatest preference for soybean of the three bean species tested in this study.

  17. Suscetibilidade de genótipos de feijão ao vírus-do-mosaico-dourado

    Directory of Open Access Journals (Sweden)

    Lemos Leandro Borges

    2003-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a suscetibilidade de diversos genótipos de feijão ao vírus-do-mosaico-dourado (VMDF, transmitido pela mosca branca (Bemisia tabaci. A semeadura foi realizada na época da seca e das águas, com e sem aplicação do inseticida granulado Aldicarb (3,0 kg ha-1 do i.a. no sulco de semeadura. O delineamento experimental utilizado foi o de blocos casualizados disposto em esquema fatorial 14x2, representado por genótipos e inseticida, respectivamente, com quatro repetições. A maior infestação de mosca-branca e incidência do vírus ocorreu na época da seca, causando prejuízos à produção do feijoeiro. Os genótipos apresentaram diferentes graus de suscetibilidade ao vírus e ao inseto vetor. Os genótipos mais tolerantes foram IAPAR 57, IAPAR 65, IAPAR 72, Ônix, Aporé e 606 (5(214-17. A aplicação do inseticida sistêmico controla o vetor em ambas as épocas de cultivo, proporcionando aumentos da produtividade.

  18. Qualidade pós-colheita de goiabas 'Branca de Kumagai', tratadas com cloreto de cálcio Post-harvest quality of guavas 'Branca de Kumagai', treated with calcium chloride

    Directory of Open Access Journals (Sweden)

    RENATO VASCONCELOS BOTELHO

    2002-04-01

    Full Text Available Com o objetivo de estudar o efeito do tratamento pós-colheita com cloreto de cálcio, pelo método da temperatura diferenciada, na conservação e qualidade de goiabas 'Branca de Kumagai', conduziu-se experimento em que frutos, na temperatura de 26ºC, foram imersos em soluções de cloreto de cálcio a 5ºC, nas concentrações de 0%; 0,5%; 1,5%; 2,5% e 3,5%. A testemunha foi representada por frutos que não receberam qualquer tipo de aplicação. Após a imersão, os frutos foram mantidos à temperatura ambiente. O tratamento na concentração de 0,5% de cloreto de cálcio estendeu em 34,8% (3,2 dias o período de conservação dos frutos, reduziu a taxa respiratória e a perda de massa fresca, aumentou ligeiramente os teores de sólidos solúveis totais, sem alterar a acidez titulável e o teor de ácido ascórbico. O tratamento a 0% de cloreto de cálcio reduziu a conservação e aumentou a taxa respiratória dos frutos, indicando que a temperatura da solução de 5ºC, foi prejudicial ao metabolismo dos frutos.A trial was conducted to verify the effect of post-harvest treatment with calcium chloride by the temperature differential method on the shelf-life and quality of guavas 'Branca de Kumagai'. The treatments consisted in dipping fruits with pulp temperature at 26ºC in solutions at 5ºC of different calcium chloride concentrations: 0%, 0,5%, 1,5%, 2,5% e 3,5%. The control did not receive any kind of application. After dipping, fruits were kept under environmental conditions. The treatment with 0,5% of calcium chloride extended the shelf-life in 34,8% (3,2 days, decreased respiration rate and fresh weight loss, slightly increased the total soluble solids content, but not change the acid ascorbic content and the tritable acidity. The treatment at 0% of calcium chloride decreased its shelf-life, indicating that the solution temperature of 5ºC was harmful to the fruit metabolism.

  19. O Estado Novo português e a reforma do Estado colonial em Angola: o comportamento político das elites brancas (1961-1962

    Directory of Open Access Journals (Sweden)

    Fernando Tavares PIMENTA

    2014-12-01

    Full Text Available Este artigo coloca em perspectiva a problemática das relações políticas e institucionais entre diferentes níveis de governação da administração colonial portuguesa e entre esta e os estratos superiores da comunidade branca de Angola. Para o efeito, definimos um triângulo analítico constituído por: a Estado central, representado pelo Ministério do Ultramar; b Estado colonial, representado pelo Governo Geral de Angola; c as elites brancas de Angola, representadas pelas respectivas associações económicas. A análise incide fundamentalmente no biénio 1961/1962, que coincidiu com o início da guerra de independência de Angola e com a subsequente experiência de reformismo colonial promovida por Adriano Moreira.

  20. The freshwater crab, Trichodactylus fluviatilis (Latreille, 1828) (Crustacea, Decapoda, Trichodactylidae), as perceived by the inhabitants of the county of Pedra Branca, Bahia, Brazil

    OpenAIRE

    Eraldo Medeiros Costa Neto

    2007-01-01

    Freshwater crabs are key elements of the aquatic biota of streams, rivers, lakes, and dams because of their ecological and economic importance. Considering that Trichodactylus fluviatilis (Latreille, 1828) is an important source of food for the human settlements that inhabit the places of its occurrence, this article records, for the first time, an ethnocarcinological study carried out with the inhabitants of Pedra Branca county, Bahia State. Data were obtained from February to June 2005 by m...

  1. Flutuação populacional de moscas-das-frutas em pomares de citros no oeste de Santa Catarina, Brasil Population fluctuation of fruit flies in citrus orchards in the West of Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Luís Antônio Chiaradia

    2004-04-01

    Full Text Available As moscas-das-frutas (Diptera, Tephritidae causam danos econômicos em muitas frutíferas. Para conhecer a flutuação populacional destas moscas em pomares de citros da região Oeste de Santa Catarina, Brasil, e estudar as interferências de fatores climáticos sobre estes insetos, cinco frascos "caça-mosca", tendo vinagre de vinho tinto a 25% como atrativo, foram semanalmente instalados em dois pomares de laranjeiras da variedade Valência, em Águas de Chapecó e Chapecó, no período de outubro de 1999 a setembro de 2001. As moscas capturadas nas armadilhas foram triadas no Laboratório de Fitossanidade da Epagri de Chapecó. Análises de correlação e regressão polinomial foram realizadas entre o número mensal de moscas do gênero Anastrepha e os dados mensais de precipitação pluviométrica, insolação, umidade relativa do ar, velocidade do vento e temperatura ambiente. Temperatura máxima e mínima mostraram interferir na população destas moscas mais do que os outros fatores climáticos. O número mensal acumulado de moscas capturadas foi submetido à análise de regressão não linear, que revelou picos de captura destes insetos de março a junho. Anastrepha fraterculus (Wiedemann, 1830 predominou sobre outras espécies de moscas-das-frutas.Fruit flies (Diptera, Tephritidae cause economic damages in many fruit orchards. To know the population fluctuation of these flies in Citrus orchards in the west of Santa Catarina, Brazil, and to study the environmental factor interferences on these insects, five traps with 25% vinegar were weekly installed in two orange Valência variety orchards, in Águas de Chapecó and Chapecó, from October of 1999 to September of 2001. The samples of flies trap captured were counted at Epagri Fitossanity Laboratory in Chapecó. A correlation and regression polynomial analyses between flies monthly captured of genus Anastrepha and monthly datas of rain precipitation, isolation, air humidity, wind speed

  2. Caracterización de daños de moscas del género dasiops (diptera: lonchaeidae) en passiflora spp. (passifloraceae) cultivadas en colombia / characterization of damage of the genus dasiops flies (diptera: lonchaeidae) from cultivated passiflora (passiflor

    OpenAIRE

    Maikol Yohanny Santamaría Galindo; Ángela Patricia Castro Ávila; Everth Emilio Ebratt Ravelo; Helena Luisa Margarita Brochero

    2014-01-01

    Resumen. Las moscas del género Dasiops Rondani constituyen la plaga más limitante en cultivos de pasifloras en Colombia, por lo que el reconocimiento de especies es importante para la toma de decisiones de vigilancia y control. Se caracterizaron los síntomas y daños producidos por moscas Dasiops spp.. en botones florales y frutos de maracuyá (Passiflora edulis f. flavicarpa Sims), gulupa (Passiflora edulis f. edulis Sims), granadilla (Passiflora ligularis Juss) y curuba (Passiflora tripartita...

  3. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae y su posible actividad adaptativa

    Directory of Open Access Journals (Sweden)

    Eneida Torres Cabra

    2014-06-01

    Full Text Available La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realizó una caracterizaciónin silico de las proteínas Hsp70 y Hsp90 de B. tabaci, secuencias obtenidas de NCBI. La determinaciónde los perfiles de hidrofobicidad, polaridad, accesibilidady flexibilidad se obtuvieron con “ProScale” de ExPASy, el perfil de antigenicidad con JaMBW. La secuencia aminoacídica se analizó con GOR IV y SOPMA y la composición de aminoácidos con ProtParam. Para analizar el peso molecular, índice deinestabilidad, índice alifático y gradiente hidropático,con GRAVY. La estructura terciaria se obtuvo con HHpred, y ESyPred3D. Para validar las estructuras 3D se utilizó Procheck, What_check y errat. Hsp70 y Hsp90 de B. tabaci presentan valores bajos de hidrofobicidady altos de polaridad, flexibilidad y accesibilidad, características que le permiten a las proteínas extender su capacidad como chaperonas. La Hsp70tiene una estructura secundaria compuesta por 41-45% alfa hélices, 30-43% coil y menos del 6% en hoja plegada y la Hsp90 por 52 y 53% hélices, 26-34% coily 6% hoja plegada. Las Hsp juegan un rol importante en los insectos debido a su tamaño y corto ciclo de vida, pues la temperatura influye en su distribución y abundancia.

  4. Nível de infestação de moscas-das-frutas em faixa de fronteira, no Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Naymã Pinto Dias

    2013-08-01

    Full Text Available As moscas-das-frutas são as principais pragas da fruticultura mundial, destacando-se os tefritídeos e os lonqueídeos, sendo que, sobre este último grupo de insetos, existem poucas informações a respeito do seu potencial de danos. O objetivo deste trabalho foi identificar os níveis de infestação de moscas-das-frutas, em municípios da faixa de fronteira do Rio Grande do Sul com a Argentina e o Uruguai. O estudo foi realizado em 2011 e 2012, nos municípios de Itaqui, Quaraí, Santana do Livramento e Uruguaiana, RS. Foram realizadas coletas de frutos de 19 espécies vegetais exóticas e nativas, calculando-se os índices de infestação em pupários/kg de fruto e pupários/fruto. O maior índice de infestação de Ceratitis capitata ocorreu em nectarineira, com 72,01 pupários/kg e 2,51 pupários/fruto. Anastrepha fraterculus apresentou índices elevados em cerejeira, correspondendo a 57,57 pupários/kg e 0,23 pupários/fruto. Os lonqueídeos foram representados pelos gêneros Neosilba e Lonchaea, infestando frutos de mamoeiro e caramboleira, respectivamente. Registra-se para os municípios estudados do Rio Grande do Sul a ocorrência das seguintes espécies de moscas-das-frutas: C. capitata, A. fraterculus, Neosilba zadolicha e Lonchaea sp.

  5. Experimentos virtuales sobre una mosca vagabunda: más allá de la solución de Neumann

    OpenAIRE

    Talero, Paco; Mora, Cesar; Organista,Orlando; Galindo,Fabian

    2013-01-01

    Se extiende el problema tradicional que pregunta por la distancia que recorre una mosca con rapidez constante cuando se mueve entre dos trenes en movimiento uniforme rectilíneo con dirección de colisión. Se revisa tanto la solución trivial como la atribuida a Neumann y mediante una simulación se amplía el problema para incluir trenes acelerados. Este problema puede usarse en cursos de física elemental para ilustrar la relación física-matemática, dar contexto al análisis gráfico y estudiar div...

  6. Bloodmeal Identification in Field-Collected Sand Flies From Casa Branca, Brazil, Using the Cytochrome b PCR Method.

    Science.gov (United States)

    Carvalho, G M L; Rêgo, F D; Tanure, A; Silva, A C P; Dias, T A; Paz, G F; Andrade Filho, J D

    2017-07-01

    PCR-based identification of vertebrate host bloodmeals has been performed on several vectors species with success. In the present study, we used a previously published PCR protocol followed by DNA sequencing based on primers designed from multiple alignments of the mitochondrial cytochrome b gene used to identify avian and mammalian hosts of various hematophagous vectors. The amplification of a fragment encoding a 359 bp sequence of the Cyt b gene yielded recognized amplification products in 192 female sand flies (53%), from a total of 362 females analyzed. In the study area of Casa Branca, Brazil, blood-engorged female sand flies such as Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1924), and Nyssomyia whitmani (Antunes & Coutinho, 1939) were analyzed for bloodmeal sources. The PCR-based method identified human, dog, chicken, and domestic rat blood sources. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Update on the Status of Bemisia tabaci in the UK and the Use of Entomopathogenic Fungi within Eradication Programmes

    Directory of Open Access Journals (Sweden)

    Andrew G. S. Cuthbertson

    2013-05-01

    Full Text Available The sweetpotato whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae continues to be a serious threat to crops worldwide. The UK holds Protected Zone status against this pest and, as a result, B. tabaci entering on plant material is subjected to a policy of eradication. Both B and Q Bemisia biotypes are now regularly intercepted entering the UK. With increasing reports of neonicotinoid resistance in both these biotypes, it is becoming more problematic to control/eradicate. Therefore, alternative means of control are necessary. Entomopathogenic fungi (Lecanicilllium muscarium and Beauveria bassiana offer much potential as control agents of B. tabaci within eradication programmes in the UK.

  8. Construction of a viral vector based on DNA-A of Tomato rugose mosaic virus (ToRMV) for induction of gene silencing in host plants

    OpenAIRE

    Cardoso, Mariana Santos

    2009-01-01

    Os begomovírus pertencem à família Geminiviridae, que inclui vírus com genoma composto por uma ou duas moléculas de DNA circular de fita simples, encapsidado em partículas icosaédricas geminadas. Os begomovírus são transmitidos pela mosca branca Bemisia tabaci e causam doenças de importância econômica em diversas culturas, principalmente em regiões tropicais e subtropicais. No Brasil, há diversos relatos de begomovírus causando sérias perdas nas culturas do feijoeiro e tomateiro e relatos esp...

  9. ANÁLISE FAUNÍSTICA DE ESPÉCIES DE MOSCA-DAS-FRUTAS (DIP., TEPHRITIDAE EM MINAS GERAIS

    Directory of Open Access Journals (Sweden)

    N.A. CANAL

    1998-01-01

    Full Text Available Em seis locais de quatro municípios (Janaúba, Jaíba, Nova Porteirinha e Itacarambí do norte do Estado de Minas Gerais, foram coletados 29.454 espécimes de mosca-das-frutas, pertencentes a Ceratitis capitata e a 20 espécies de Anastrepha. O levantamento foi feito entre janeiro de 94 e dezembro de 96, utilizando armadilhas plásticas tipo McPhail. Ceratitis capitata foi a espécie predominante em áreas urbanas. As espécies de Anastrepha predominaram em áreas rurais. A. obliqua, A. zenildae e Anastrepha n. sp.3 foram as espécies predominantes do gênero, entretanto, essa predominância variou de local para local em função da disponibilidade de hospedeiros. As comunidades apresentaram índices de diversidade baixos e quocientes de similaridade entre 73 e 100%.A total of 29,454 specimens of fruit fly were trapped in six sites of four counties (Janaúba, Jaíba, Nova Porteirinha and Itacarambí of the north of the State of Minas Gerais, Brazil. The specimens were collected using McPhail plastic traps from January 1994 to December 1996. The trapped fruit flies belonged to Ceratitis capitata and to 20 species of Anastrepha. Ceratitis capitata was the predominant species in the urban areas and Anastrepha species were predominant in the field areas. A. obliqua, A. zenildae and Anastrepha n. sp.3 were the predominant species of the genera, whereas the predominant species differed among localities, according to host availability. The diversity indexes were low and the coefficient of similarity varied from 73 to 100%.

  10. Improved DNA barcoding method for Bemisia tabaci and related Aleyrodidae: development of universal and Bemisia tabaci biotype-specific mitochondrial cytochrome c oxidase I polymerase chain reaction primers.

    Science.gov (United States)

    Shatters, Robert G; Powell, Charles A; Boykin, Laura M; Liansheng, He; McKenzie, C L

    2009-04-01

    Whiteflies, heteropterans in the family Aleyrodidae, are globally distributed and severe agricultural pests. The mitochondrial cytochrome c oxidase I (mtCOI) sequence has been used extensively in whitefly phylogenetic comparisons and in biotype identification of the agriculturally important Bemisia tabaci (Gennadius) whitefly. Because of the economic importance of several whitefly genera, and the invasive nature of the B and the Q biotypes of Bemisia tabaci, mtCOI sequence data are continually generated from sampled populations worldwide. Routine phylogenetic comparisons and biotype identification is done through amplification and sequencing of an approximately 800-bp mtCOI DNA fragment. Despite its routine use, published primers for amplification of this region are often inefficient for some B. tabaci biotypes and especially across whitefly species. Through new sequence generation and comparison to available whitefly mtCOI sequence data, a set of polymerase chain reaction (PCR) amplification primers (Btab-Uni primers) were identified that are more efficient at amplifying approximately 748 bp of the approximately 800-bp fragment currently used. These universal primers amplify an mtCOI fragment from numerous B. tabaci biotypes and whitefly genera by using a single amplification profile. Furthermore, mtCOI PCR primers specific for the B, Q, and New World biotypes of B. tabaci were designed that allow rapid discrimination among these biotypes. These primers produce a 478-, 405-, and 303-bp mtCOI fragment for the B, New World, and Q biotypes, respectively. By combining these primers and using rapid PCR and electrophoretic techniques, biotype determination can be made within 3 h for up to 96 samples at a time.

  11. A reliable begomovirus inoculation method for screening Lycopersicon esculentum lines Um método de inoculação de begomovírus confiável para a seleção de linhagens de Lycopersicon esculentim

    Directory of Open Access Journals (Sweden)

    Alice K Inoue-Nagata

    2007-09-01

    Full Text Available Due to failures of infection after mechanical inoculation of begomovirus on tomato (Lycopersicon esculentum Mill. plants, an efficient and reliable begomovirus inoculation method was developed using the whitefly vector (Bemisia tabaci. Virus acquisition was carried out using a 'Tube-cage', made of a polypropylene tube, containing one to two day-old whiteflies and a tomato plant apex infected with a begomovirus isolate. After 48 h of acquisition access period, inoculation was done using a 'Ring-cage', containing viruliferous whiteflies, attached to the abaxial side of the leaf of young tomato plants. 48 hours after acquisition, the whiteflies were eliminated and the inoculated plants were incubated for 28 days under greenhouse conditions. Three viruliferous whiteflies per plant were enough to cause infection in susceptible tomato cv. Viradoro. This procedure was applied to test the resistance of tomato line 486-1 (resistant line in comparison with 'Viradoro' (susceptible cultivar. Dot blot hybridization confirmed the susceptibility of 'Viradoro' and the resistance of the line 486-1, showing the efficiency of this method for screening plants for disease resistance. This method is also a useful tool in detecting the presence of virus in inoculated (lower leaves and in non-inoculated (upper leaves in a given plant. Using this procedure, it was observed that the resistance of the line 486-1 probably is expressed in the inoculated leaf without virus translocation to the upper leaves.Devido às falhas encontradas no método de inoculação de begomovírus em plantas de tomateiro, um método eficiente e confiável de inoculação de begomovírus foi desenvolvido utilizando como vetor a mosca-branca (Bemisia tabaci. A aquisição viral foi realizada em uma armadilha ('Tube-cage' feita a partir de um tubo de polipropileno contendo moscas-brancas de um ou dois dias de idade e o ápice de uma planta de tomate infectada com um begomovírus. Após 48 horas de

  12. Records of Natural Enemies of Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) Biotype B in Brazil.

    Science.gov (United States)

    Torres, L C; Lourenção, A L; Costa, V A; Souza, B; Costa, M B; Tanque, R L

    2014-04-01

    Collections of natural enemies of Bemisia tabaci biotype B (Genn.) (Hemiptera: Aleyrodidae) were made in Lavras, state of Minas Gerais, Brazil. In the greenhouse, 6,495 predators and 16,628 parasitoids belonging to three families were collected. In the field, 267 predators and 344 parasitoids belonging to five families were found. For the first time in Brazil, five species of predators associated with this whitefly were reported. Because of the diversity of natural enemies of B. tabaci biotype B recorded, this study points out the importance of these data for studies on integrated pest management.

  13. Identification of Chinese populations of Bemisia tabaci (Gennadius) by analyzing ribosomal ITS1 sequence

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Spreading of Bemisia tabaci B biotype has had a large impact on the production of vegetables, ornamental and fiber crops in many countries of the world since the 1990s. This study analyzes the ribosomal ITS1 sequence (~520 bp) to distinguish genetic difference of B. tabaci from representative different geographical populations in China. Phylogenetic analysis shows that populations of B.tabaci from Beijing and Shandong Province are of biotype B, and populations of B.tabaci from sweet potato in Fujian Province and pumpkin in Guangxi, China, belong to two different non-B biotypes and have a geographical origin of Asia.

  14. Effectiveness of BPMC Application against Bemisia tabaci (Gennadius Population and CMMV Disease Incidence on Soybean

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    Wartono Wartono

    2015-09-01

    Full Text Available Control of whitefly (Bemisia tabaci (Gennadius is the starting point in suppressing the CMMV disease (cowpea mild mottle virus. This study aims to determine the influence of applications BPMC (500 g a.i./l against B. tabaci populations and disease incidence of CMMV on soybean plants. Research was conducted in the field with randomized complete block design consisting of 5 treatments i.e. five concentration levels: 0.75, 1.50,2.25, and 3.00 ml/l including control (untreated with 5 replications. The results showed that BPMC is effective in suppressing the adult population of B. tabaci and disease incidence of CMMV.

  15. Infestação da mosca-negra-dos-citros (Aleurocanthus woglumi Ashby em pomares de citros, em sistemas de plantio convencional e agroflorestal

    Directory of Open Access Journals (Sweden)

    Anderson Gonçalves Da Silva

    2011-03-01

    Full Text Available Objetivou-se com o presente trabalho avaliar a infestação da mosca-negra-dos-citros em pomares de citros, em sistemas de plantio convencional e agroflorestal. A área experimental está localizada no município de Capitão Poço-PA, onde foram realizadas 12 amostragens durante o período de setembro de 2008 a outubro de 2009, avaliando a presença ou a ausência da praga nas laranjeiras, em ambos os sistemas de produção. Pelos resultados obtidos, observou-se que o sistema de plantio agroflorestal apresentou maior incidência de plantas com presença de mosca-negra-dos-citros comparado ao convencional, houve influência da temperatura na regulação da população da praga, e precipitações elevadas reduziram o número de plantas com presença de A. woglumi.

  16. Purificação e estudo de algumas propriedades do vírus da necrose branca do fumo

    Directory of Open Access Journals (Sweden)

    Darcy M. Silva

    1961-01-01

    Full Text Available Experimentos relativos à purificação do vírus da necrose branca do fumo, em geral instável aos processos de purificação, mostraram ser possível obter preparações razoàvelmente homogêneas partindo-se de plantas por êle infetadas. O processo de purificação constou de uma clarificação preliminar através da adsorção de diversos componentes do suco de planta, ao qual foi adicionado dietilditiocarbamato de sódio a 0,1 M e tampão de fosfato pH 8,0 e a 0,1 M em fosfato hidradatado de cálcio, seguida de ultracentrifugações diferenciais. Os resultados das purificações a partir de Nicotiana tabacum L. var. xanthi, Solanum nigrum L. e Datura stramonium L. doentes, mostraram-se consistentes com respeito à presença de pellets após duas ultracentrifugações, o mesmo não acontecendo com as plantas contrôles. Tais preparações apresentaram infetuosidade até o terceiro dia após a extração do suco. Exames ao microscópio eletrônico das suspensões das pellets acima mencionadas em água destilada, mostraram a existência de partículas esferóides com um diâmetro ao redor de 50 milimicra. Injeções em coelho, via íntravenosa, num total de 7 doses de 2-3 ml de suspensão do vírus da necrose branca do fumo, preparadas diariamente pelo processo já referido, mas com uma só ultracentrifugação, provocaram a formação de anticorpos para o mesmo, conforme se pôde constatar pelos testes de precipitina de difusão em ágar.This work presents the results of the purification of the Brazilian tobacco streak virus from material of different three host plant species. The procedure consisted of a preliminar clarification through the adsorption of several components of the juice from diseased plants extracted with phosphate buffer at pH 8,0, 0,1, M and sodium diethyl ditbio carbamate at 0,1 M on hidrated calcium phosphate and two or more ultracentrifugation cycles. Pellets were obtained from diseased Nicotiana tubacum L. var. xanthi

  17. House Fly (Musca domestica L. (Diptera Muscidae Development in Different Types of Manure Desarrollo de la Mosca Doméstica (Musca domestica L. (Díptera Muscidae en Distintos Tipos de Estiércol

    Directory of Open Access Journals (Sweden)

    Patricia Larraín S

    2008-06-01

    Full Text Available Animal production units with different management systems can be found along the Huasco Valley, Region of Atacama, Chile. These constitute sources of house flies (Musca domestica L. and other vector fly species that cause damage to animals and nuisance problems in urban areas. In order to asses the importance of fly breeding sources, an experiment was carried out under laboratory conditions to evaluate different types of animal manure and composted swine manure. Time of larval development, larva mortality, pupa size, and weight and time of development to the adult stage were assessed. Results show that swine, poultry and calf manure produced a significantly higher number of adult flies, shorter life cycles and larger and heavier pupae. Cow, dog, goat and horse manure follow in effectiviveness for fly production. Composted swine manure was totally ineffective for domestic fly development.En algunas comunas del Valle del Huasco, Región de Atacama, Chile, se encuentran diversas explotaciones pecuarias con diferentes sistemas de manejo, las cuales constituyen focos generadores de mosca doméstica, Musca domestica L., y otras especies de moscas con importancia sanitaria y médica. Estos insectos provocan pérdidas económicas en dichos planteles afectando además el bienestar de poblaciones urbanas cercanas. Con el objetivo de cuantificar la importancia de dichos focos en la generación de mosca doméstica, se realizó un ensayo de laboratorio donde se evaluó como sustrato de desarrollo del insecto estiércol de diferentes especies animales y estiércol de cerdo compostado. La calidad de estos sustratos en la producción del insecto se evaluó a través de los siguientes parámetros biológicos: tiempo de desarrollo de larvas, mortalidad de larvas, tamaño y peso de pupas, y tiempo hasta la emergencia de moscas adultas. Los resultados indicaron que el estiércol de cerdo, gallina y ternero produce significativamente más moscas adultas, con un

  18. Study of the pathosystem: Begomovirus Bemisia tabaci I tomato on the South West islands of the Indian Ocean

    NARCIS (Netherlands)

    Delatte, H.

    2005-01-01

    Tomato yellow leaf curl virus (TYLCV) belongs to the genus Begomovirus within the Geminiviridae family, and is exclusively transmitted by the whitefly species Bemisia labaci (Hemiptera: Aleyrodidae) (Gennadius). It is an emerging virus which since the 1980's has globally spread over many tropical, s

  19. Identification of the MEAM1 cryptic species of Bemisia tabaci (Hemiptera: Aleyrodidae) by loop-mediated isothermal amplification

    Science.gov (United States)

    There are two major invasive cryptic species within the Bemisia tabaci cryptic species complex in Florida, called MEAM1 or biotype B, and MED or biotype Q. We used loop-mediated isothermal amplification of DNA to detect these groups. Primer sets developed in house and those previously published wer...

  20. Entomopathogenic fungi against whiteflies : tritrophic interactions between Aschersonia species, Trialeurodes vaporariorum and Bemisia argentifolii, and glasshouse crops

    NARCIS (Netherlands)

    Meekes, E.T.M.

    2001-01-01

    Many horticultural and agricultural crops are good host plants for the greenhouse whitefly, Trialeurodes vaporariorum, and the silverleaf whitefly, Bemisia argentifolii . Their damage to crops is manifold. When present in sufficient numbers they can

  1. Study of the pathosystem: Begomovirus Bemisia tabaci I tomato on the South West islands of the Indian Ocean

    NARCIS (Netherlands)

    Delatte, H.

    2005-01-01

    Tomato yellow leaf curl virus (TYLCV) belongs to the genus Begomovirus within the Geminiviridae family, and is exclusively transmitted by the whitefly species Bemisia labaci (Hemiptera: Aleyrodidae) (Gennadius). It is an emerging virus which since the 1980's has globally spread over many tropical,

  2. Tomato yellow leaf curl virus can be acquired and transmitted by Bemisia tabaci (Gennadius) from tomato fruits

    NARCIS (Netherlands)

    Delatte, H.; Dalmon, A.; Rist, D.; Soustrade, I.; Wuster, G.; Lett, J.M.; Goldbach, R.W.; Peterschmitt, M.; Reynaud, B.

    2003-01-01

    The whitefly Bemisia tabaci is an insect pest causing worldwide economic losses, especially as a vector of geminiviruses such as Tomato yellow leaf curl virus (TYLCV). Currently, imported and exported tomato fruit are not monitored for TYLCV infection because they are not considered to represent a

  3. Entomopathogenic fungi against whiteflies. Tritrophic interactions between Aschersonia species, Trialeurodes vaporariorum and Bemisia argentifolii, and glasshouse crops

    NARCIS (Netherlands)

    Meekes, E.T.M.

    2001-01-01

    Many horticultural and agricultural crops are good host plants for the greenhouse whitefly, Trialeurodes vaporariorum, and the silverleaf whitefly, Bemisia argentifolii . Their damage to crops is manifold. When present in sufficient numbers they can cause leaf drop and inhibit fruit maturation. They

  4. Genome sequencing and analysis of the whitefly (Bemisia tabaci) MEAM1, one of the most important vectors for plant viruses

    Science.gov (United States)

    Among whiteflies, the Bemisia tabaci (Hemiptera: Aleyrodidae) species complex is particularly important because of its ability to transmit hundreds of plant viruses, resulting in the loss of billions of U.S. dollars on agronomically important crops such as tomato, cucurbits, cassava, and cotton worl...

  5. Comparison of three single-nozzle operator-carried spray applicators for whitefly (Bemisia tabaci) management on squash

    Science.gov (United States)

    Whiteflies cause problems in vegetable production on a global scale. The primary worldwide whitefly pest is Bemisia tabaci (Gennadius). Insecticides are commonly used to mitigate the whitefly problem in vegetable crops. In limited-resource crop production, operator-carried spray applicators are comm...

  6. Estimation of the whitefly Bemisia tabaci genome size based on k-mer and flow cytometry analyses

    Science.gov (United States)

    Whiteflies, Bemisia tabaci (Hemiptera: Aleyrodidae), are one of the most important agricultural insect pests in the world. These phloem-feeding insects can colonize over 500 crop plants worldwide and inflict severe economic losses, mainly through the transmission of pathogenic viruses. Surprisingl...

  7. Genetic distinctions among the Mediterranean and Chinese populations of Bemisia tabaci Q biotype and their endosymbiont Wolbachia populations

    Science.gov (United States)

    The sweetpotato whitefly, Bemisia tabaci, is a cryptic species complex composed of more than 24 different biotypes around the world. The Q biotype of B. tabaci, which is thought to have originated in the Mediterranean Basin, is now a widespread and serious agricultural pest. In this study, the genet...

  8. The Feeding Rate of Predatory Mites on Life Stages of Bemisia tabaci Mediterranean Species

    Directory of Open Access Journals (Sweden)

    Andrew G. S. Cuthbertson

    2014-07-01

    Full Text Available The sweetpotato whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae continues to be a serious threat to crops worldwide. The UK holds Protected Zone status against this pest and, as a result, B. tabaci entering on plant material is subjected to a policy of eradication. There has recently been a shift from Middle East-Asia Minor 1 to the more chemical resistant Mediterranean species entering the UK. Predatory mites (Amblyseius swirskii, Transeius montdorensis and Typhlodromalus limonicus were screened for their impact upon various lifestages of B. tabaci Mediterranean species. Approximately 30% of eggs were fed upon by A. swirskii following a 5 day period. Feeding rates slightly decreased for all mite species when feeding on first instar life-stages (27%, 24%, 16% respectively and significantly decreased when feeding on second instars (8.5%, 8.5%, 8.7% respectively. Combining the two mite species (A. swirskii and T. montdorensis increased mortality of Bemisia eggs to 36%. The potential of incorporating the mites into existing control strategies for B. tabaci is discussed.

  9. Phylogenetic Analysis and Rapid Identification of the Whitefly, Bemisia afer, in China

    Science.gov (United States)

    Chu, Dong; Liu, Guoxia; Wan, Fanghao; Tao, Yunli; Gill, Ray J

    2010-01-01

    The phylogenetic relationship between the whitefly Bemisia afer (Priesner & Hosny) (Hemiptera: Aleyrodidae) from China and other populations among the world were analyzed based on the mitochondrial cytochrome oxidase I (mtCOI) gene. Phylogenetic analysis of mtCOI sequences and those of reference B. afer sequences showed that the populations of the species could be separated into 5 clades (I–V). There were at least two clades of the species from China (IV and V). These data suggested that B. afer might be a species complex. The Chinese B. afer populations were most divergent with B. afer from the United Kingdom and African countries. The distance between the Chinese B. afer (IV and V) and clades I, II, and III is more than 32%, while the distance among clades I, II, III is lower than 7.7%. A new set of primers specific to B. afer was designed to amplify a region of approximately 400 bp to discriminate B. afer from other Bemisia species in China based on mtCOI sequences. PMID:20673071

  10. Effects of selected fertilizers on the life history of Bemisia tabaci (Hemiptera: Aleyrodidae) biotype B.

    Science.gov (United States)

    England, K M; Sadof, C S; Cañnas, L A; Kuniyoshi, C H; Lopez, R G

    2011-04-01

    We tested the effects among a purportedly sustainable water-soluble fertilizer, a conventional water-soluble fertilizer, an alternation of these, a controlled-release fertilizer, and a clear water control on the life-history traits of sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae; =Bemisia argentifolii Bellows & Perring) biotype B reared on poinsettia (Euphorbia pulcherrima Willdenow ex Klotzch). Free amino acids in petioles were measured to estimate plant nutrient assimilation and phloem nutritional quality for B. tabaci biotype B. The sustainable fertilizer produced plants with the highest concentration of amino acids. In contrast, fecundity of whiteflies was lowest in plants treated with the sustainable fertilizer and the water control. The relationship between total amino acids in phloem and survival was significantly quadratic, with the highest survival at intermediate levels. Fecundity, however, was negatively correlated with total amino acid content of the maternal host plant. Variation in total amino acid concentration in petioles of plants treated within fertilizer treatments makes it difficult to predict whether a particular fertilizer will produce plants with enough amino acids to deleteriously affect both survivorship and fecundity and yet yield a plant of good quality. Despite this limitation, we can conclude that the use of this sustainable fertilizer will not cause increases in whitefly populations relative to plants fertilized with water-soluble and slow-release fertilizers that deliver the same level of nitrogen to the plant.

  11. Study on the Occurrence Regularity of Invasive Whitefly Bemisia Tabaci Population

    Directory of Open Access Journals (Sweden)

    Xu Senfu

    2013-11-01

    Full Text Available The B biotype whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae is an invasive species in China, witch severely damage the production of numerous crops through direct feeding and transmission of plant viruses. In order to clarify the major biological characteristics of a whitefly as an alien invasive species, reveal the seasonal growth and decline of its population quantity, the law of fluctuation from year to year and it’s influencing factors and improves the monitoring, prevention and control level. Our study investigates the main biological characteristics and the population quantity’s fluctuation of the whitefly Bemisia tabaci in Linhai, Zhejiang province, China. Adult whiteflies were investigated in the greenhouse and field from 2006 to 2011 with using yellow sticky boards. The results show that the whiteflies can produce 11 generations each year with an evident generation overlapping. The number of whiteflies in the greenhouse started to increase from June, with a significant increase after July and then reached its peak during August and September. With the temperature drop, the whitefly population started to decrease after mid-October. The observation of the insects indicated that whiteflies are capable of surviving within the whole year under the greenhouse condition. On the other hand, the overwintering frequency for the whitefly in the open field was approximately 20%. Moreover, the main factors that affect the population dynamics of whiteflies in the field include the initial population number, climate condition, farming system and flood inundation, among which, the temperature condition is the most important.

  12. La percepción de diplopoda (arthropoda, myriapoda) por los habitantes del poblado de pedra branca, santa teresinha, bahía, brasil

    OpenAIRE

    ERALDO M. COSTA NETO

    2011-01-01

    Este artículo registra las concepciones, los conocimientos y los comportamientos que los habitantes del poblado de Pedra Branca, en el estado de Bahía, poseen sobre los artrópodos de la clase Diplopoda. Los datos fueron obtenidos desde febrero hasta junio de 2005 a través de entrevistas abiertas y semiestructuradas realizadas con 28 individuos de ambos sexos, con edades que variaron de 13 a 86 años. Se registraron los conocimientos tradicionales relacionados con taxonomía, biología, há...

  13. The literary vision of the exile as a synthesis of Baroja’s political experience: the case of Susana y los cazadores de moscas

    Directory of Open Access Journals (Sweden)

    Francesca Crippa

    2015-12-01

    Full Text Available In his short novel titled Susana y los cazadores de moscas (1938, Baroja tells the story of an ordinary person who finds himself compelled to live in another country because of the Civil War. Baroja partially identifies himself in his main character, whose name is Miguel Salazar, because he himself had to build a new life in Paris, where he decided to go after the war broke out. The aim of this work is to analyze the novel according to the ideological and biographical correspondences between the author and the main character in order to confirm the possibility of an autobiographical interpretation for one of the less known novels written by the Basque writer.

  14. Alguém mais belo do que eu: Alberto Caeiro, Leopold Bloom, o Portugal de Pessoa, a Irlanda de Joyce e outras Brancas de Neve

    Directory of Open Access Journals (Sweden)

    Inês Lage Pinto Basto

    2012-10-01

    Full Text Available Ao definir-se como um quarto de espelhos fantásticos, Fernando Pessoa encontra no espelho a única certeza comum a todas as “reflexões falsas”, a materialização da “única anterior realidade” que os seus inúmeros espelhos “torcem”. Tomando a Branca de Neve como uma sublimação final da beleza usurpadora da Madrasta e a corporização de uma beleza inicial, considerarei os “inúmeros espelhos fantásticos” de Pessoa e o “cracked looking glass” de Joyce como distorcidas sequelas de uma qualquer pureza de origem ou de uma superfície reflectora una. Argumento que Caeiro, Bloom, o Império Espiritual de Pessoa e a “Irlanda Caricatura do Mundo Sério” de Joyce virão a ser a materialização dessa superfície reflectora de origem, Brancas de Neve posteriores às realidades que lhes são madrastas mas colocadas estrategicamente na sua origem e destinadas a suprir a ausência de uma “única anterior realidade” – pessoal, nacional e global.

  15. Tectonic insights of the southwest Amazon Craton from geophysical, geochemical and mineralogical data of Figueira Branca mafic-ultramafic suite, Brazil

    Science.gov (United States)

    Louro, Vinicius H. A.; Cawood, Peter A.; Mantovani, Marta S. M.; Ribeiro, Vanessa B.

    2017-06-01

    The Figueira Branca Suite is a layered mafic-ultramafic complex in the Jauru Terrane, southwest Amazon Craton. New lithological, geochemical, gamma-ray and potential field data, integrated with geological, isotope and paleomagnetic data are used to characterize this pulse of Mesoproterozoic extension-related magmatism. The Figueira Branca Suite formed through juvenile magma emplacement into the crust at 1425 Ma, coeval with the later stages of the Santa Helena Orogen. Gabbros and peridotite-gabbros display increasing enrichment of LREE, interpreted as evidence of progressive fractionation of the magma. Magnetic and gamma-ray data delimit the extent of magmatism within the suite to four bodies to the north of Indiavaí city. Modelling gravity and magnetic field data indicate that the anomalous sources are close to the surface or outcropping. These intrusions trend northwest over 8 km, with significant remanent magnetization that is consistent with published direction obtained through paleomagnetic data. The emplacement, mineralogy and geochemical signature point towards a back-arc extension tectonic framework in the later stages of the Santa Helena Orogen.

  16. Susceptibility of the horn fly, Haematobia irritans irritans (Diptera: Muscidae, to insecticides in Brazil Suscetibilidade da mosca-dos-chifres, Haematobia irritans irritans (Diptera: Muscidae, a inseticidas no Brasil

    Directory of Open Access Journals (Sweden)

    Antonio Thadeu Medeiros Barros

    2012-06-01

    Full Text Available Since horn fly populations became established throughout Brazil, complaints regarding control failure have increased around the country. A broad survey to evaluate the susceptibility of horn flies to both organophosphate (OP and pyrethroid insecticides was conducted from October 2000 to April 2003. Bioassays using filter papers impregnated with cypermethrin, permethrin or diazinon were conducted on 154 horn fly populations in 14 states and 78 municipalities. Resistance to cypermethrin, the active ingredient present in most insecticide products for horn fly control in Brazil, was detected in 98.46% of the populations, with resistance ratios (RR ranging from 2.5 to 719.9. Resistance to permethrin (RRs Desde a dispersão da mosca-dos-chifres, no Brasil, queixas sobre seu controle aumentaram em todo o país. Um amplo levantamento objetivando avaliar a suscetibilidade da mosca a inseticidas organofosforados (OF e piretróides foi realizado de outubro de 2000 a abril de 2003. Bioensaios com papéis de filtro impregnados com cipermetrina, permetrina ou diazinon foram conduzidos em 154 populações da mosca-dos-chifres de 14 Estados e 78 municípios. Resistência à cipermetrina, ingrediente ativo presente na maioria dos produtos para controle da mosca-dos-chifres no Brasil, foi detectada em 98,46% das populações, com fatores de resistência (FR variando de 2,5 a 719,9. Resistência à permetrina (FR < 6,3 foi encontrada em 96,67% das populações testadas, apesar da falta de uso de produtos contendo este princípio ativo. Em geral, resistência a piretróides foi detectada em 97,18% das populações, com frequências acima de 87% em todas as regiões do país. A situação da suscetibilidade da mosca-dos-chifres a inseticidas, no Brasil, pode ser caracterizada por uma elevada suscetibilidade aos organofosforados e ocorrência generalizada de resistência aos piretróides, potencialmente comprometendo a eficácia desses produtos na maioria dos casos

  17. Efectos del daño de la mosca del olivo y del atroje sobre la microflora en pasta y la acidez del aceite virgen de oliva

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    Martínez, J. A.

    2003-09-01

    Full Text Available The effects of olive fly damage, olive storage, harvest date, olive grove plot and their interactions on the microflora associated with olive paste and oil acidity were studied. Microflora and oil acidity were significantly affected by the four studied factors and by several interactions between them. Fly damage and olive storage interacted sinergically increasing oil acidity. The relationship between fly damage and oil acidity was lineal although sometimes it was not significant depending on microflora populations. The relationship between microflora populations and oil acidity fitted to a logarithmic model. Major microorganisms in olive paste were bacteria (Xanthomonas, yeasts (mostly Torulopsis and Candida and in a smaller measure moulds (mainly Fusarium and Penicillium. Results overall suggest that a qualitative damage threshold based on the percentage of damaged fruits in order to infer oil acidity may be unfeasible in most instances.Se estudiaron los efectos del daño de mosca, atroje, fecha de recolección, parcela de olivo y de sus interacciones, sobre la microflora asociada a la pasta de aceituna y la acidez del aceite obtenido. Microflora y acidez se vieron significativamente afectados por los cuatro factores estudiados y por varias de sus interacciones. Daño y atroje interactuaron sinérgicamente para incrementar la acidez. La relación entre el daño de mosca y la acidez fue lineal aunque a veces no fue significativa dependiendo de la microflora. La relación entre la microflora y la acidez se ajustó a un modelo logarítmico. Los microorganismos predominantes en la pasta fueron bacterias (Xanthomonas, levaduras (fundamentalmente Torulopsis y Candida y en menor medida otros hongos (principalmente Fusarium y Penicillium. Los resultados sugieren que un umbral de daño cualitativo basado en el porcentaje de frutos picados para inferir la acidez del aceite es de difícil implementación.

  18. Impact of cotton planting date and nitrogen fertilization on Bemisia argentifolii populations

    Institute of Scientific and Technical Information of China (English)

    JIAN-LONGBI; DONG-MEILIN; KEH-SHENLII; NICKC.TOSCANO

    2005-01-01

    The silverleaf whitefly (Bemisia argentifolii Bellows and Perring) is a widely distributed pest of cotton (Gossypium hirsutum L.) and the population levels may be affected by rates of nitrogen fertilization and planting date. Field experiments were conducted to investigate the impact of cotton planting date and nitrogen fertilization on silverleaf whitefly population dynamics. Cotton was planted on 26 April and 8 June, for the early and late plantings, respectively. Nitrogen treatments consisted of soil applications of 0, 112, 168 and 224 kg of nitrogen per hectare. The population levels of adult whiteflies were much higher on early-planted cotton than on late planting. Also, increased numbers of adult whiteflies on both early and late plantings occurred with increasing amounts of applied nitrogen.Applied nitrogen increased seed cotton yields of early plantings but had no effect on the yields of late plantings.

  19. Indigenous American species of the Bemisia tabaci complex are still widespread in the Americas.

    Science.gov (United States)

    Barbosa, Leonardo da F; Marubayashi, Julio M; De Marchi, Bruno R; Yuki, Valdir A; Pavan, Marcelo A; Moriones, Enrique; Navas-Castillo, Jesús; Krause-Sakate, Renate

    2014-10-01

    Bemisia tabaci is a complex of at least 36 putative cryptic species. Since the late 1980s, the Middle East-Asia Minor 1 species (MEAM1, formerly known as the B biotype), has emerged in many tropical and subtropical regions of the world and in some areas has displaced the indigenous populations of B. tabaci. Based on analysis of the mtCOI gene, two indigenous species native to America have been reported: New World (NW, formerly the A biotype) and New World 2 (NW2). NW is present at least in Argentina, Brazil, Martinique, Mexico, Texas and Venezuela, and NW2 in Argentina, Bolivia and Brazil. Wild plants (Euphorbia sp. and Ipomoea sp.), as well as important crops such as tomato, bean and cotton, are still hosts for native B. tabaci populations in the Americas. MEAM1 has not completely displaced the native B. tabaci from the Americas. © 2014 Society of Chemical Industry.

  20. Wolbachia Has Two Different Localization Patterns in Whitefly Bemisia tabaci AsiaII7 Species.

    Science.gov (United States)

    Shi, Peiqiong; He, Zhan; Li, Shaojian; An, Xuan; Lv, Ning; Ghanim, Murad; Cuthbertson, Andrew G S; Ren, Shun-Xiang; Qiu, Bao-Li

    2016-01-01

    The whitefly Bemisia tabaci is a cosmopolitan insect species complex that harbors the obligate primary symbiont Portiera aleyrodidarum and several facultative secondary symbionts including Wolbachia, which have diverse influences on the host biology. Here, for the first time, we revealed two different localization patterns of Wolbachia present in the immature and adult stages of B. tabaci AsiaII7 cryptic species. In the confined pattern, Wolbachia was restricted to the bacteriocytes, while in the scattered pattern Wolbachia localized in the bacteriocytes, haemolymph and other organs simultaneously. Our results further indicated that, the proportion of B. tabaci AsiaII7 individuals with scattered Wolbachia were significantly lower than that of confined Wolbachia, and the distribution patterns of Wolbachia were not associated with the developmental stage or sex of whitefly host. This study will provide a new insight into the various transmission routes of Wolbachia in different whitefly species.

  1. [Transmission of tomato Venezuela virus by Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), in Maracaibo, Venezuela].

    Science.gov (United States)

    Romay, Gustavo; Geraud-Pouey, Francis; Chirinos, Dorys T; Morales, Francisco; Herrera, Emilio; Fernández, Carlos; Martínez, Ana K

    2010-01-01

    The biological transmission of Tomato Venezuela virus (ToVEV) by biotype B of the whitefly species Bemisia tabaci (Gennadius) increased (21.7-95.0%), and the time for symptom expression decreased (16-12.6 days) as the number of viruliferous whiteflies allowed access for inoculation to susceptible tomato plants increased from 1 to 20 adults/plant. When acquired only as a nymph, adults of this biotype transmitted the virus to 88.3% of susceptible tomato plants, using 15 viruliferous individuals per test plant, corroborating the circulative nature of the transmission. Disease incidence further increased (up to 100%) when the individuals were allowed to feed again on a virus-infected plant as adults. Leaf area, plant height and dry matter were significantly affected in ToVEV infected tomato plants.

  2. PENGGUNAAN PREDATOR UNTUK MENGENDALIKAN KUTU KEBUL (BEMISIA TABACI, VEKTOR PENYAKIT KUNING PADA CABAI DI KABUPATEN TANGGAMUS

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    Sudiono & Purnomo .

    2011-11-01

    Full Text Available Application of predators to control  whitefly (Bemisia tabaci, an insect vector of yellow diseases of chili in Tanggamus district on dry and rainy season.  The yellow disease is one of the important diseases in chili which is transmitted by whitefly.  Utilization of natural enemy such as predators is one of some methods in controlling whitefly.  This study was conducted in Gisting, Tanggamus District, Lampung province from June 2009 to January 2010.  The objective of this research was to determine effectiveness of controlling whitefly by its predators: Menochilus sp., Micraspis sp., and Paederus sp.  The results showed that Menochilus, Micraspis, and Paederus could effectively decrease the population of whitefly.  The three predators were more effective in rainy than in dry season.

  3. Effect of starvation on vein preference of whitefly (Bemisia tabaci) on chilli as host plant

    Science.gov (United States)

    Siti Sakinah, A.; Mohamad Roff M., N.; Idris, A. B.

    2014-09-01

    The whitefly, Bemisia tabaci (Gennadius), is a cosmopolitan pest of horticultural crops. It caused serious damaged to the plants by feeding on plant saps as direct damage and transmit virus as indirect damage. Vein preferences of both female and male whitefly (WF) on chilli plant were recorded using Dinolite, a portable microscope, under laboratory conditions. WF adults of both sexes were starved for 2 and 4 hours before used for observation while no starvation for control individual (treatment). Results showed that both female and male preferred to feed on secondary veins rather than lamina, midrib and vein. From the result of whitefly preferred target site, hopefully this information will help to improve control tactics in WF management.

  4. Sublethal effects of some synthetic and botanical insecticides on Bemisia tabaci (Hemiptera: Aleyrodidae

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    Esmaeily Saeideh

    2014-07-01

    Full Text Available In addition to direct mortality caused by insecticides, some biological traits of insects may also be affected by sublethal insecticide doses. In this study, we used the age-stage, two-sex life table method to evaluate the sublethal effects of the four synthetic insecticides: abamectin, imidacloprid, diazinon, and pymetrozin as well as the botanical insecticide taken from Calotropis procera (Asclepiadaceae extract, on eggs of the cotton whitefly, Bemisia tabaci (Hem.: Aleyrodidae. The lowest and highest survival rates and oviposition periods were observed in whiteflies treated by diazinon and imidacloprid, respectively. We found significant differences in the net reproductive rate (R0, the intrinsic rate of increase (r, the finite rate of increase (?, and the gross reproductive rate (GRR among different insecticides. Altogether, our results showed that pymetrozin and C. procera induced the most sublethal effects, thus they may be suitable candidates for use in integrated pest management programs of B. tabaci.

  5. Diversity and evolution of the Wolbachia endosymbionts of Bemisia (Hemiptera: Aleyrodidae) whiteflies

    Science.gov (United States)

    Bing, Xiao-Li; Xia, Wen-Qiang; Gui, Jia-Dong; Yan, Gen-Hong; Wang, Xiao-Wei; Liu, Shu-Sheng

    2014-01-01

    Wolbachia is the most prevalent symbiont described in arthropods to date. Wolbachia can manipulate host reproduction, provide nutrition to insect hosts and protect insect hosts from pathogenic viruses. So far, 13 supergroups of Wolbachia have been identified. The whitefly Bemisia tabaci is a complex containing more than 28 morphologically indistinguishable cryptic species. Some cryptic species of this complex are invasive. In this study, we report a comprehensive survey of Wolbachia in B. tabaci and its relative B. afer from 1658 insects representing 54 populations across 13 provinces of China and one state of Australia. Based on the results of PCR or sequencing of the 16S rRNA gene, the overall rates of Wolbachia infection were 79.6% and 0.96% in the indigenous and invasive Bemisia whiteflies, respectively. We detected a new Wolbachia supergroup by sequencing five molecular marker genes including 16S rRNA, groEL, gltA, hcpA, and fbpA genes. Data showed that many protein-coding genes have limitations in detecting and classifying newly identified Wolbachia supergroups and thus raise a challenge to the known Wolbachia MLST standard analysis system. Besides, the other Wolbachia strains detected from whiteflies were clustered into supergroup B. Phylogenetic trees of whitefly mitochondrial cytochrome oxidase subunit I and Wolbachia multiple sequencing typing genes were not congruent. In addition, Wolbachia was also detected outside the special bacteriocytes in two cryptic species by fluorescence in situ hybridization, indicating the horizontal transmission of Wolbachia. Our results indicate that members of Wolbachia are far from well explored. PMID:25077022

  6. Sequence Analysis of mtDNA COIGene and Molecular Phylogeny of Different Geographical Populations of Bemisia tabaci (Gennadius)

    Institute of Scientific and Technical Information of China (English)

    CHU Dong; ZHANG You-jun; CONG Bin; XU Bao-yun; WU Qing-jun; ZHU Guo-ren

    2005-01-01

    Bemisia tabaci(Gennadius) is a serious pest in many cropping systems worldwide and occurs in different biotypes. The mtDNA COI gene of the 12 Bemisia tabaci (Gennadius) populations from different regions and countries were analyzed.Based on mtDNA COI sequences, their biotypes were characterized and phylogenetic relationships among these populations were established with the method of UPGMA. The results indicated the genetic similarity between those populations from Beijing, Zhengzhou, Zaozhuang, Nanjing, Shanghai, Haikou, and the B-biotype populations from California, Texas, Arizona reached 99.8-100%, which meant the nation-wide infested populations of B. tabaci in China in recent years were B-biotypes. Another population collected from Kunming of Yunnan Province showed very high similarity with Q-biotype B. tabaci from Spain and Morocco, which meant the Kunming population was Q-biotype. This is the first report on the invasion of Q-biotype into China.

  7. Olfactory response of predatory Macrolophus caliginosus Wagner (Heteroptera: Miridae) to the odours host plant infested by Bemisia tabaci

    Science.gov (United States)

    Saad, Khalid A.; Roff, M. N. Mohamad; Salam, Mansour; Hanifah Mohd, Y.; Idris, A. B.

    2014-09-01

    Plant infested with herbivores, release volatile that can be used by natural enemies to locate their herbivorous prey. Laboratory studies were carried out to determine the olfactory responses of predator Macrolophus caliginosus Wagner (Heteroptera: Miridae), to chili plant infected with eggs, nymphs of Bemisia tabaci, using Y-tube olfactometer. The results shown that predator, M. caliginosus has ability to discriminate between non-infested and infested plant by B. tabaci. Moreover, the predator preferred plants with nymphs over plants with eggs. This suggested that M. caliginous uses whitefly-induced volatile as reliable indicators to distinguish between infested chili plants by nymphs, eggs and non-infested plants. These results enhance our understanding of the olfactory cues that guide foraging by M. caliginosus to plant with and without Bemisia tabaci.

  8. Umbu-cajá como repositório natural de parasitoide nativo de moscas-das-frutas Umbu-cajá as natural repository of native fruit fly parasitoids

    Directory of Open Access Journals (Sweden)

    Romulo da Silva Carvalho

    2010-10-01

    Full Text Available O objetivo deste trabalho foi avaliar diversidade de espécies de mosca-das-frutas e de parasitóides nativos em frutos de umbu-cajá (Spondias spp.. Os frutos foram coletados em nove municípios do Estado da Bahia. Estimaram-se: a infestação dos frutos pelas moscas; o índice de parasitismo das moscas; e a frequência de ocorrência das espécies de parasitóides. Pela primeira vez, a infestação de Anastrepha obliqua em frutos de umbu-cajá e a presença do parasitóide Asobara anastrephae em larvas de Anastrepha obliqua foram registradas. O parasitoide nativo Doryctobracon areolatus foi o mais frequente. A umbu-cajazeira é repositório natural de parasitoides de tefritídeos, e sua preservação é fundamental para a manutenção das relações tróficas entre as espécies de mosca-das-frutas e parasitoides.The objective of this work was to assess the species diversity of fruit fly and their parasitoids in fruit of umbu-cajá (Spondias spp.. Fruit were collected in nine municipalities of the state of Bahia, Brazil. Fruit infestation, fruit fly parasitism rates, and frequencies of the parasitoid species were estimated. For the first time, Anastrepha obliqua infesting umbu-cajá fruit and the presence of the native parasitoid Asobara anastrephae in Anastrepha oblique larvae were recorded. The native parasitoid Doryctobracon areolatus was the most frequent. Umbu-cajá tree is a natural repository of Tephritidae parasitoids, and its preservation is essential for the maintenance of trophic relationships between fruit fly species and parasitoids.

  9. Moscas-das-frutas em pomares de pessegueiro e maracujazeiro, no Município de Iraceminha, Santa Catarina, Brasil Fruit flies in peach and passion fruit orchards in Iraceminha, Santa Catarina, Brazil

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    Sheila Alberti

    2009-08-01

    Full Text Available Este estudo teve o objetivo de caracterizar a comunidade de moscas-das-frutas de ocorrência em pomares de pessegueiro e maracujazeiro, no Município de Iraceminha, Santa Catarina (SC, por meio da análise faunística. Os adultos de moscas-das-frutas foram capturados semanalmente, em armadilhas McPhail, contendo glicose invertida a 10%, no período de abril de 2006 a março de 2007. Na caracterização, foram calculados os índices de abundância, constância, dominância, frequência e diversidade. Foram coletados 697 adultos de moscas-das-frutas. Anastrepha grandis e Anastrepha fraterculus foram as espécies mais abundantes, frequentes, constantes e dominantes nos pomares estudados, predominando sobre as outras espécies de moscas-das-frutas. Ceratitis capitata foi caracterizada como dispersa e pouco frequente. O maior índice de diversidade encontrado foi de 1,99 no pomar de maracujazeiro.This research had the objective to characterize the community of fruit flies in peach and passion fruit orchards in Iraceminha, Santa Catarina, Brazil, through faunistic analyses. The adults fruit flies were weekly captured in McPhail traps with 10% inverted glucose, from April 2006 to March 2007. In the characterization, the indices for abundance, constancy, dominance, frequency and diversity were calculated. A total of 697 adults fruit flies were collected. Anastrepha grandis and Anastrepha fraterculus species were the most abundant, frequent, constant and dominant in orchards studied, predominating upon other fruit flies species. Ceratitis capitata was dispersed and not very frequent. The biggest index of diversity of 1.99 was in passion fruit orchard.

  10. Dinâmica populacional e incidência de moscas-das-frutas e parasitoides em cultivares de pessegueiros (Prunus Persica L. Batsch no município de presidente prudente-sp

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    Sônia Maria Nalesso Marangoni Montes

    2011-06-01

    Full Text Available Esta pesquisa teve como objetivos avaliar a dinâmica populacional e registrar a diversidade de moscas-das-frutas (Diptera: Tephritoidea em cultivares de pessegueiro Tropical, Talismã, Aurora 2, Aurora 1, Dourado 2 e Doçura 2, enxertadas sobre os porta-enxertos 'Okinawa' e Umê, em Presidente Prudente-SP. Foram realizadas as correlações da dinâmica populacional com a temperatura e a precipitação, e também a infestação com as características químicas dos frutos, Sólidos Solúveis e Acidez Titulável. No período de julho de 2004 a dezembro de 2006, a dinâmica populacional de moscas-das-frutas foi obtida através de coletas semanais de moscas-das-frutas em armadilhas McPhail, e a incidência foi determinada através da coleta de 30 frutos/planta/cultivar. O delineamento estatístico adotado foi o inteiramente casualizado, com cinco repetições. Ceratitis capitata foi predominante nas cultivares de pessegueiros estudadas. Não foi observada correlação significativa entre população de moscas-das-frutas e as variáveis de temperatura e precipitação, e sólidos solúveis e ácidez titulável. Entre as cultivares de pêssego, Aurora 2 apresentou maior infestação por C. capitata, da ordem de 22 e 23% nos anos 2004 e 2006, respectivamente. Também foi registrada a incidência de Neosilba spp. em frutos de pêssego. Doryctobracon areolatus (Braconidae, Tetrastichus giffardianus (Eulophidae e Pachycrepoideus vindemmiae (Pteromalidae foram recuperados de pupários de Tephritidae.

  11. Glutathione S-transferases are involved in thiamethoxam resistance in the field whitefly Bemisia tabaci Q (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Yang, Xin; He, Chao; Xie, Wen; Liu, Yating; Xia, Jixing; Yang, Zezong; Guo, Litao; Wen, Yanan; Wang, Shaoli; Wu, Qingjun; Yang, Fengshan; Zhou, Xiaomao; Zhang, Youjun

    2016-11-01

    The whitefly, Bemisia tabaci, has developed a high level of resistance to thiamethoxam, a second generation neonicotinoid insecticide that has been widely used to control this pest. In this study, we assessed the level of cross-resistance, the activities of detoxifying enzymes, and the expression profiles of 23 glutathione S-transferase (GST) genes in a thiamethoxam-resistant ant and -susceptible strain of Bemisia tabaci Q. The thiamethoxam-resistant strain showed a moderate level of cross-resistance to another nicotinoid insecticide imidacloprid, a low level of cross-resistance to acetamiprid and nitenpyram, and no significant cross-resistance to abamectin and bifenthrin. Among detoxifying enzymes, only GSTs had significantly higher activity in the resistant strain than in the susceptible strain. Seven of 23 GST genes were over-expressed in the resistant strain relative to the susceptible strain. Using the technology of RNA interference to knockdown a GST gene (GST14), the results showed that silencing GST14 increased the mortality of whiteflies to thiamethoxam in Bemisia tabaci.

  12. Novas determinações dos parâmetros atmosféricos das estrelas anãs brancas DA

    Science.gov (United States)

    Giovannini, O.; Costa, A. F. M.; Kepler, S. O.

    2003-08-01

    Nós temos selecionado uma amostra de estrelas anãs brancas DA (atmosfera de hidrogênio) a partir dos índices de Strömgren cujos valores estão próximos a região de instabilidade das estrelas anãs brancas DA variáveis, as chamadas estrelas DAV ou ZZ Ceti. O objetivo é determinar os parâmetros fundamentais (temperatura efetiva, Teff, aceleração da gravidade, log g, e massa) destas estrelas para verificar quais os parâmetros estelares estão envolvidos com o mecanismo de pulsação das estrelas DAV. Nós obtemos, até agora, mais de 120 espectros óticos de estrelas DA. Entre as estrelas selecionadas há 20 estrelas variáveis (DAV). Assim, podemos verificar se existem ou não estrelas não variáveis dentro da faixa de instabilidade das estrelas ZZ Ceti. Neste trabalho nós apresentamos a determinação dos parâmetros atmosféricos (temperatura efetiva, Teff, e aceleração da gravidade, log g) das estrelas anãs brancas DA usando os novos modelos de atmosfera ML2/a = 0.6. Estes modelos têm sido utilizados recentemente por fornecerem uma excelente consistência interna na determinação das temperaturas nas regiões do ultra-violeta e ótico. Os parâmetros atmosféricos são determinados espectroscopicamente através da comparação do fluxo de energia das linhas de Balmer (Hb à H9) entre os espectros observados e sintéticos (gerados pelos modelos de atmosfera). As temperaturas obtidas com os novos modelos são, em geral, menores (~ 1000 K menos) que as temperaturas determinadas anteriormente, com modelos ML1. Os valores de log g não mudaram significativamente (menos de 10%). A faixa de instabilidade das DAVs está entre 11000 e 13000 K, consistente com dados de outros autores.

  13. Progresso genético no melhoramento da aveia-branca no Sul do Brasil Genetic progress in oat breeding in Southern Brazil

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    JOSÉ F. BARBOSA NETO

    2000-08-01

    Full Text Available As cultivares de aveia-branca (Avena sativa L. cultivadas no sul do Brasil até princípios da década de 80 eram provenientes do Uruguai e da Argentina, apresentando problemas de adaptação ao ambiente de cultivo. A partir dos anos 70, programas de melhoramento começaram a produzir suas próprias populações segregantes, possibilitando o lançamento em escala comercial de cerca de 35 cultivares. Com o objetivo de estimar o progresso genético nos programas de melhoramento de aveia-branca do sul do Brasil, foi realizado um experimento envolvendo 15 cultivares lançadas em diferentes épocas, em dois locais, com quatro diferentes condições de manejo. Os resultados obtidos indicaram progresso genético linear para os caracteres ciclo vegetativo, rendimento de grãos, peso de grão e peso do hectolitro; a inexistência de efeitos quadráticos significativos sugeriram a possibilidade de ganhos posteriores a partir da seleção de novos genótipos. Os programas de melhoramento genético de aveia-branca do sul do Brasil, embora ainda não tenham atingido o patamar máximo, têm sido eficientes em produzir novas cultivares com maiores rendimento e qualidade de grãos e com caracteres agronômicos superiores.The oat (Avena sativa L. cultivars cultivated in Southern Brazil up to the beginning of the 80's were introduced from Uruguay and Argentina. They presented adaptation problems to the new environment. Starting from the 70's, oat breeding programs began to produce their own segregant populations. These programs already released 35 cultivars. Aiming to estimate the genetic progress in oat breeding programs from southern Brazil, an experiment with 15 cultivars released in different times was conducted in two locations using four different cultural practices. The results indicated linear genetic progress for days to flowering, grain yield, grain weight and test weight. The non significance of quadratic effects suggested the possibility of additional

  14. THE PERCEPTION OF DIPLOPODA (ARTHROPODA, MYRIAPODA BY THE INHABITANTS OF THE COUNTY OF PEDRA BRANCA, SANTA TERESINHA, BAHIA, BRAZIL La percepción de diplopoda (Arthropoda, Myriapoda por los habitantes del poblado de Pedra Branca, Santa Teresinha, Bahía, Brasil

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    ERALDO M COSTA NETO

    2007-11-01

    Full Text Available This paper deals with the conceptions, knowledge and attitudes of the inhabitants of the county of Pedra Branca, Bahia State, on the arthropods of the class Diplopoda. Data were collected from February to June 2005 by means of openended interviews carried out with 28 individuals, which ages ranged from 13 to 86 years old. It was recorded some traditional knowledge regarding the following items: taxonomy, biology, habitat, ecology, seasonality, and behavior. Results show that the diplopods are classified as “insects”. The characteristic of coiling the body was the most commented, as well as the fact that these animals are considered as “poisonous”. In general, the traditional zoological knowledge of Pedra Branca’s inhabitants concerning the diplopods is coherent with the academic knowledge.Este artículo registra las concepciones, los conocimientos y los comportamientos que los habitantes del poblado de Pedra Branca, en el estado de Bahía, poseen sobre los artrópodos de la clase Diplopoda. Los datos fueron obtenidos desde febrero hasta junio de 2005 a través de entrevistas abiertas y semiestructuradas realizadas con 28 individuos de ambos sexos, con edades que variaron de 13 a 86 años. Se registraron los conocimientos tradicionales relacionados con taxonomía, biología, hábitat, ecología, estacionalidad y comportamiento. Los resultados muestran que los diplópodos son clasificados como “insectos”. La característica de enrollar el cuerpo fue la más comentada, así como el hecho de que la mayoría de los individuos cree que estos animales son ponzoñosos. En general, el conocimiento zoológico tradicional que los pobladores de Pedra Branca tienen acerca de los diplópodos se mostró coherente con el conocimiento académico.

  15. La percepción de diplopoda (Arthropoda, Myriapoda por los habitantes del poblado de Pedra Branca, Santa Teresinha, Bahía, Brasil The perception of diplopoda (Arthropoda, Myriapoda by the inhabitants of the country of Pedra Branca Santa Teresinha, Bahía, Brasil

    Directory of Open Access Journals (Sweden)

    Costa Neto Eraldo M.

    2007-08-01

    Full Text Available Este artículo registra las concepciones, los conocimientos y los comportamientos que los habitantes del poblado de Pedra Branca, en el estado de Bahía, poseen sobre los artrópodos de la clase Diplopoda. Los datos fueron obtenidos desde febrero hasta junio de 2005 a través de entrevistas abiertas y semiestructuradas realizadas con 28 individuos de ambos sexos, con edades que variaron de 13 a 86 años. Se registraron los conocimientos tradicionales relacionados con taxonomía, biología, hábitat, ecología, estacionalidad y comportamiento. Los resultados muestran que los diplópodos son clasificados como “insectos”. La característica de enrollar el cuerpo fue la más comentada, así como el hecho de que la mayoría de los individuos cree que estos animales son ponzoñosos. En general, el conocimiento zoológico tradicional que los pobladores de Pedra Branca tienen acerca de los diplópodos se mostró coherente con el conocimiento académicoThis paper deals with the conceptions, knowledge and attitudes of the inhabitants of the county of Pedra Branca, Bahia State, on the arthropods of the class Diplopoda. Data were collected from February to June 2005 by means of openended interviews carried out with 28 individuals, which ages ranged from 13 to 86 years old. It was recorded some traditional knowledge regarding the following items: taxonomy, biology, habitat, ecology, seasonality, and behavior. Results show that the diplopods are classified as “insects”. The characteristic of coiling the body was the most commented, as well as the fact that these animals are considered as “poisonous”. In general, the traditional zoological knowledge of Pedra Branca’s inhabitants concerning the diplopods is coherent with the academic knowledge.

  16. Direitos sexuais, direitos reprodutivos: concepções de mulheres negras e brancas sobre liberdade Sexual and reproductive rights: the conceptions of black and white women regarding freedom

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    Raquel Souzas

    2007-08-01

    Full Text Available A saúde reprodutiva relaciona-se ao usufruto da liberdade intrínseca aos direitos sexuais e reprodutivos. A questão central, neste artigo, é como a noção de liberdade se articula à condição social, de gênero, raça/etnia, com o intuito de investigar diferenças de gênero e de raça nas questões reprodutivas de mulheres negras e brancas, em relação à concepção de liberdade. A pesquisa é de natureza qualitativa e aborda questões reprodutivas de mulheres, a partir de um recorte de gênero e raça. Foram entrevistadas 36 mulheres, autoclassificadas brancas e negras (pretas e pardas, em união conjugal há, pelo menos, um ano. Os discursos foram analisados articulando-se raça/etnia e diferentes níveis de escolaridade. No conjunto, observa-se que as condições de vida e saúde reprodutiva de mulheres negras e brancas diferenciam-se em razão das condições socioeconômicas e culturais. Comparativamente, os discursos dos dois grupos podem ser interpretados em dois níveis característicos, da vida privada e do espaço público: enquanto mulheres brancas focam a defasagem das mulheres, no exercício eqüitativo da liberdade em relação aos homens, mas destacam conquistas no mundo do trabalho, mulheres negras pensam a liberdade mais circunscrita à possibilidade de vivência democrática da conjugalidade. As diferenças de discurso em relação à liberdade podem estar relacionadas tanto à questão do racismo no Brasil, historicamente vivenciado por mulheres negras no cotidiano, como às questões especificamente culturais dos dois grupos estudados.Reproductive health is related to the enjoyment of freedom that is intrinsic to sexual and reproductive rights. The core issue, in this article, is how the notion of freedom articulates itself to the social condition of gender, race and ethnicity. To investigate gender and race differences in reproductive issues of black and white women regarding the conception of freedom. The research

  17. The freshwater crab, Trichodactylus fluviatilis (Latreille, 1828 (Crustacea, Decapoda, Trichodactylidae, as perceived by the inhabitants of the county of Pedra Branca, Bahia, Brazil

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    Eraldo Medeiros Costa Neto

    2007-03-01

    Full Text Available Freshwater crabs are key elements of the aquatic biota of streams, rivers, lakes, and dams because of their ecological and economic importance. Considering that Trichodactylus fluviatilis (Latreille, 1828 is an important source of food for the human settlements that inhabit the places of its occurrence, this article records, for the first time, an ethnocarcinological study carried out with the inhabitants of Pedra Branca county, Bahia State. Data were obtained from February to June 2005 by means of open-ended interviews using the usual techniques of ethnographical survey. Sixteen women and eleven men were interviewed. Their ages ranged from 25 to 86 years old. The results showed that the ethnocarcinological knowledge about T. fluviatilis is relatively consistent with academic knowledge. Ethnozoological studies that stress the cultural significance of freshwater crustaceans are very important, since they would represent a great contribution to the debate on biodiversity conservation in the environments these animals inhabit.

  18. Elaboração de fiambres com as carnes branca e escura de frango Chicken loaves prepared with broiler light and dark meat

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    M. Graner

    1992-01-01

    Full Text Available O presente trabalho teve como objetivo específico a obtenção de fiambres com as carnes branca (do peito e escura (das coxas e pernas de frango, separadamente. Os cortes foram desossados manualmente e às carnes, após limpeza e corte, foram adicionados ingredientes não cárneos e aditivos, sendo elas moídas após 12 h. O processamento térmico foi realizado em defumador até a temperatura interna de 71°C. Foram obtidos fiambres curados e defumados com boa qualidade sensorial, adequado nível de proteína e baixo conteúdo calórico, do tipo semi-conserva. O rendimento foi maior na elaboração do fiambre de carne branca, o qual foi preferido na avaliação sensorial, em relação ao produto de carne escura.Chiken loaves were prepared with light and dark meat from broiler and deboned breasts and legs. The meat was cut, cured, ground, smoked and pasteurized (until 71°C. The yield was greater for the loaf prepared with light meat, which was also ranked first in sensory analysis. The light and the dark meat loaves had the following chemical compositions: moisture 70.6 - 71.0%; protein 22.0 - 20.2%; moisture/protein ratio 3.2 - 3.5; fat 4.0 - 4.5%; sodium chloride 2.4 - 2.5%; sodium nitrite 51.5 - 69.0 ppm; pH 6.1 - 6.25, respectively.

  19. INFLUÊNCIA DA TEMPERATURA E PRECIPITAÇÃO NA INFESTAÇÃO DE MOSCA-NEGRA-DOS-CITROS (Aleurocanthuswoglumi EM PLANTIO DE CITROS

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    BOIÇA JUNIOR, Arlindo Leal

    2011-05-01

    Full Text Available The citrus industry in the state of Pará, has important economic and social role, by raisingforeign currency for the state, besides employment generation and the heating of the local economy. Among themajor disease problems of the state, the citrus blackfly (Aleurocanthus woglumi, stands out for causing damagesthat can compromise up to 80% of production. Thus the objective was with the present work to evaluate theinfluence of abiotic factors (temperature and precipitation in a natural infestation of blackfly in the citrusplanting in the state of Pará. The study was conducted from September 2008 to August 2009. Were performed 12samples by assessing the infestation in the experimental area. Were used correlations between infestation ofplants with presence of blackfly and ace variables rainfall (mm and minimum temperature, average andmaximum (° C. As main conclusions, stand out that the experimental area was found to be infested during allassessments, the monthly average temperature (° C influenced in the regulation of pest population and heavyrain reduced the infestation of blackfly of citrus.A citricultura, no estado do Pará, exerce importante papel econômico e social, através dearrecadação de divisas para o estado; além da geração de empregos e aquecimento da economia local. Dentre osprincipais problemas fitossanitários do estado, a mosca-negra-dos-citros (Aleurocanthus woglumi, destaca-sepor acarretar prejuízos que podem comprometer até 80% da produção. Dessa forma objetivou-se com o presentetrabalho avaliar a influência de fatores abióticos (temperatura e precipitação na infestação natural de moscanegra-dos-citros em plantio de citros no estado do Pará. O trabalho foi desenvolvido de setembro de 2008 aagosto de 2009. Fez-se 12 amostragens avaliando-se a infestação da praga na área experimental. Utilizou-secorrelações entre infestação de plantas com presença de mosca negra e ás variáveis precipitação pluviom

  20. Insecticide susceptibility of horn flies, Haematobia irritans (Diptera: Muscidae, in the State of Mato Grosso do Sul, Brazil Suscetibilidade da mosca-dos-chifres, Haematobia irritans (Diptera: Muscidae, a inseticidas no Estado de Mato Grosso do Sul, Brasil

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    Antonio Thadeu M. Barros

    2007-09-01

    Full Text Available Horn fly susceptibility to insecticides was evaluated in the state of Mato Grosso do Sul, Brazil, from October 2000 to September 2002. Insecticide bioassays (n=57 were conducted in 38 ranches from 14 municipalities throughout the state. Horn flies from wild populations were collected on cattle and exposed to filter papers impregnated with cypermethrin, permethrin, or diazinon and mortality was assessed after two hours. Resistance to cypermethrin was detected in all populations, with resistance ratios (RR ranging from 27.6 to 91.3-fold. Permethrin bioassays provided apparently low levels of resistance (RRA suscetibilidade da mosca-dos-chifres a inseticidas foi avaliada no estado de Mato Grosso do Sul de outubro/2000 a setembro/2002 com a realização dos ensaios biológicos (n=57 em 38 propriedades, de 14 municípios. Moscas coletadas em bovinos foram expostas a papéis de filtro impregnados com cipermetrina, permetrina, ou diazinon, registrando-se a mortalidade após duas horas. Resistência à cipermetrina foi detectada em todas as populações, com fatores de resistência (FR entre 27,6 e 91,3. Ensaios biológicos com permetrina resultaram em níveis de resistência aparentemente baixos (FR<5, entretanto, o uso de concentrações diagnósticas evidenciaram a ocorrência de moscas resistentes em 96,9% das populações. Considerando ambos os bioensaios com piretróides, 97,4% das populações apresentaram resistência. De outro modo, todas as populações demonstraram elevada suscetibilidade ao diazinon (FR < 1.1. Todas as propriedades onde o controle da mosca-dos-chifres era realizado (97,5% utilizavam produtos piretróides, principalmente à base de cipermetrina (92,3% e deltametrina (66,7%. Tratamentos inseticidas utilizando bombas costais manuais eram realizados em 84,5% das propriedades, geralmente de forma inadequada. O perfil de uso de inseticidas nas propriedades contribui para explicar a ampla ocorrência de resistência da mosca

  1. Espessura da polpa como condicionante do parasitismo de mosca-das-frutas (Diptera:Tephritidae por Hymenoptera: braconidae Fruit pulp thickness conditioning fruit fly (Diptera:Tephritidae parasitism by Hymenoptera: braconidae

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    Eduardo Rodrigues Hickel

    2002-12-01

    Full Text Available Dentre as estratégias de manejo integrado de mosca-das-frutas está a manutenção de refúgios, vizinhos aos pomares, para proliferação de inimigos naturais. Objetivando verificar quais hospedeiros de mosca-das-frutas seriam mais adequados para incrementar o controle natural, estabeleceu-se uma correlação entre o nível de parasitismo e a espessura da polpa de frutos. Frutos em maturação de café (Coffea arabica, jabuticaba (Myrciaria cauliflora, cajá-mirim (Spondias lutea e laranja (Citrus aurantium foram coletados e mantidos em bandejas plásticas sobre uma camada de areia. As pupas de mosca-das-frutas retiradas da areia foram mantidas em estufa incubadora para emergência dos adultos. O diâmetro dos frutos e das sementes foi medido para se calcular a espessura da polpa. O café, com 1,8mm de polpa, foi o hospedeiro em que ocorreu maior índice de parasitismo de mosca-das-frutas (13,73%. O nível de parasitismo apresentou uma correlação negativa com a espessura da polpa dos frutos, sendo os frutos de polpa fina mais adequados para proliferação de parasitóides de mosca-das-frutas.One of the strategies for fruit fly integrated pest management is the refugee maintenance, near the orchards, for fruit fly natural enemies proliferation. With the aim to check the most suitable fruit fly hosts to increment natural control, a correlation was established between the parasitism level and the fruit pulp thickness. Ripening fruits of coffee (Coffea arabica, jabuticaba (Myrciaria cauliflora, cajá-mirim (Spondias lutea, and orange (Citrus aurantium were collected and maintained in plastic trays over a sand layer. The fruit fly pupae were taken from the sand and put in B.O.D. for adult emergence. The fruit and seed diameter were measure to estimate the fruit pulp thickness. The coffee bean, with 1.8mm of pulp was the fruit fly host with the greatest parasitism level (13.37%. The level of parasitism showed a negative relation with the fruit

  2. Replication of Tomato Yellow Leaf Curl Virus in Its Whitefly Vector, Bemisia tabaci.

    Science.gov (United States)

    Pakkianathan, Britto Cathrin; Kontsedalov, Svetlana; Lebedev, Galina; Mahadav, Assaf; Zeidan, Muhammad; Czosnek, Henryk; Ghanim, Murad

    2015-10-01

    Tomato yellow leaf curl virus (TYLCV) is a begomovirus transmitted exclusively by the whitefly Bemisia tabaci in a persistent, circulative manner. Replication of TYLCV in its vector remains controversial, and thus far, the virus has been considered to be nonpropagative. Following 8 h of acquisition on TYLCV-infected tomato plants or purified virions and then transfer to non-TYLCV-host cotton plants, the amounts of virus inside whitefly adults significantly increased (>2-fold) during the first few days and then continuously decreased, as measured by the amounts of genes on both virus DNA strands. Reported alterations in insect immune and defense responses upon virus retention led us to hypothesize a role for the immune response in suppressing virus replication. After virus acquisition, stress conditions were imposed on whiteflies, and the levels of three viral gene sequences were measured over time. When whiteflies were exposed to TYLCV and treatment with two different pesticides, the virus levels continuously increased. Upon exposure to heat stress, the virus levels gradually decreased, without any initial accumulation. Switching of whiteflies between pesticide, heat stress, and control treatments caused fluctuating increases and decreases in virus levels. Fluorescence in situ hybridization analysis confirmed these results and showed virus signals inside midgut epithelial cell nuclei. Combining the pesticide and heat treatments with virus acquisition had significant effects on fecundity. Altogether, our results demonstrate for the first time that a single-stranded DNA plant virus can replicate in its hemipteran vector. Plant viruses in agricultural crops are of great concern worldwide. Many of them are transmitted from infected to healthy plants by insects. Persistently transmitted viruses often have a complex association with their vectors; however, most are believed not to replicate within these vectors. Such replication is important, as it contributes to the

  3. Genetic diversity of Bemisia tabaci (Genn. Populations in Brazil revealed by RAPD markers

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    L.H.C. Lima

    2002-01-01

    Full Text Available Bemisia tabaci (Genn. was considered a secondary pest in Brazil until 1990, despite being an efficient geminivirus vector in beans and soybean. In 1991, a new biotype, known as B. tabaci B biotype (=B. argentifolii was detected attacking weed plants and causing phytotoxic problems in Cucurbitaceae. Nowadays, B. tabaci is considered one of the most damaging whitefly pests in agricultural systems worldwide that transmits more than 60 different plant viruses. Little is known about the genetic variability of these populations in Brazil. Knowledge of the genetic variation within whitefly populations is necessary for their efficient control and management. The objectives of the present study were to use RAPD markers (1 to estimate the genetic diversity of B. tabaci populations, (2 to study the genetic relationships among B. tabaci biotypes and two other whitefly species and (3 to discriminate between B. tabaci biotypes. A sample of 109 B. tabaci female individuals obtained from 12 populations in Brazil were analyzed and compared to the A biotype from Arizona (USA and B biotype from California (USA and Paraguay. Trialeurodes vaporariorum and Aleurodicus cocois samples were also included. A total of 72 markers were generated by five RAPD primers and used in the analysis. All primers produced RAPD patterns that clearly distinguished the Bemisia biotypes and the two other whitefly species. Results also showed that populations of the B biotype have considerable genetic variability. An average Jaccard similarity of 0.73 was observed among the B biotype individuals analyzed. Cluster analysis demonstrated that, in general, Brazilian biotype B individuals are scattered independently in the localities where samples were collected. Nevertheless, some clusters were evident, joining individuals according to the host plants. AMOVA showed that most of the total genetic variation is found within populations (56.70%, but a significant portion of the variation is found

  4. Foraging by Polybia (Trichothorax ignobilis (Hymenoptera, Vespidae on flies at animal carcasses Forrageamento de Polybia (Trichothorax ignobilis sobre moscas visitantes de carcaças animais

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    Leonardo Gomes

    2007-09-01

    Full Text Available Proteins for brood nutrition of social wasps are obtained from many prey, including insects (even bees and other wasps, spiders and bits of decaying meat. After being captured and killed, prey are reduced to a shapeless mass and distributed to the brood. Little is known about the foraging activity, especially on this group. Herein we describe the sequence of foraging behaviours of the social wasp Polybia (Trichothorax ignobilis for hunting flies (Diptera: Calliphoridae and Muscidae over pig carcasses. To our knowledge, there are few scientific descriptions of prey foraging behaviour on this species.Proteínas para nutrição da prole de vespas sociais são obtidas de várias presas, incluindo insetos (mesmo abelhas e outras vespas, aranhas e pedaços de carne em decomposição. Após serem capturadas e mortas, as presas são reduzidas a massas amorfas e distribuídas para a prole. Pouco é sabido sobre a atividade de forrageamento, especialmente nesse grupo. Assim nós descrevemos a seqüência de comportamento de forrageamento da vespa social Polybia (Trichothorax ignobilis capturando moscas (Díptera: Calliphoridae e Muscidae em carcaças de porcos. Para nosso conhecimento, há poucas descrições científicas do comportamento de forrageamento nessa espécie.

  5. Población de mosca blanca en tomate cultivado a campo con pantallas de sombreamiento Whitefly population in shaded tomato field

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    Daniel Sánchez

    2005-02-01

    Full Text Available El objetivo de este trabajo fue analizar la población de mosca blanca Trialeurodes vaporariorum, Westwood (Hemiptera: Aleyrodidae en tomate de verano en cultivos con sombreado, en Santa Fe, Argentina. Se transplantó tomate en hileras cubriendo un sector con malla negra de polipropileno, realizándose cada tres días, en 30 plantas un recuento de adultos en una hoja superior y de ninfas en diez folíolos al azar. El diseño experimental fue de bloques al azar analizándose la correlación entre la temperatura y la evolución de adultos y ninfas. El sombreado disminuyó la temperatura, pero incrementó diez veces la densidad de adultos y cinco veces la de ninfas respecto al cultivo al aire libre.In Santa Fe, Argentina, whitefly (Trialeurodes vaporariorum, Westowood (Hemiptera: Aleyrodidae populations were monitored during summer in shaded and non shaded tomato field. Tomato was transplanted in rows and half of crop surface was shaded with a black polypropilen layer. Whitefly population was monitored at three-day intervals in 30 plants. Adult whiteflies were surveyed in the highest developed leaf and immature stages in 10 random leaflets in each plant. Experimental design was in randomized blocks and the correlation was calculated among temperature and number of adults and nymphs. In shaded tomato, temperature was lower but whitefly adult populations increased ten times and immature stages increased five times.

  6. UTILIZAÇÃO DA ANÁLISE DISCRIMINANTE EM ESTUDOS TAXONÔMICOS DE MOSCAS-DAS-FRUTAS DO GÊNERO Anastrepha Schiner, 1868 (DIPTERA: TEPHRITIDAE

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    E.L. ARAUJO

    1998-01-01

    Full Text Available As moscas-das-frutas Anastrepha fraterculus (Wiedemann, 1830, A. obliqua (Macquart, 1835, A. sororcula (Zucchi, 1979 e A. zenildae (Zucchi, 1979 foram submetidas a uma análise discriminante. Essas espécies do grupo fraterculus distinguem-se unicamente com base em detalhes do ápice do acúleo, que por serem muito semelhantes, dificultam a identificação específica. A análise discriminante permitiu a separação das quatro espécies de Anastrepha, com base em oito medidas do acúleo. Portanto, essa é mais uma técnica para auxiliar as identificações de espécies de Anastrepha, como já acontece em muitos outros grupos de insetos.A discriminant analysis was carried out for four species of the fraterculus group, Anastrepha fraterculus (Wiedemann, 1830, A. obliqua (Macquart, 1835, A. sororcula (Zucchi, 1979 and A. zenildae (Zucchi, 1979. These species can be distinguished only by minor morphological characters of the aculeus apex and sometimes there is great difficulty in determining specific limits. The study was based on eight measurements of the aculeus and it was possible to separate the species using the discriminant analysis. Therefore, this analysis is an additional tool for the identification of Anastrepha species as it was already observed for many other groups of insects.

  7. Diets based on soybean protein for Mediterranean fruit fly Dietas baseadas em proteína de soja para moscas do Mediterrâneo

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    Raimundo Braga Sobrinho

    2006-04-01

    Full Text Available The objective of this work was to develop suitable and economic diets for mass rearing Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae. Diets containing sugar beet bagase, wheat bran, brewer yeast, and others with wheat bran and palletized soybean protein from Brazil were tested. Diets based on soybean protein have shown promising results regarding pupal recovery, pupal weight and adult emergence. Soybean bagase in the form of pellets with 60% of protein can be a very important substitute for other expensive sources of protein.O objetivo deste trabalho foi desenvolver dietas adequadas e econômicas para a criação massal de moscas de frutas do Mediterrâneo, Ceratitis capitata (Diptera: Tephritidae. Foram testados dietas com bagaço de beterraba açucareira, farelo de trigo, levedura de cerveja e outras dietas de farelo de trigo e proteína de soja prensada brasileira. Dietas compostas por proteína de soja apresentaram resultados positivos de recuperação de pupas, pesos de pupa e emergência de adultos. O bagaço de soja, na forma de pellet com 60% de proteína, pode ser um importante substituto de outras fontes de proteína.

  8. Dinamismo econômico e batismos de ingênuos: a libertação do ventre da escrava em Casa Branca e Iguape, província de São Paulo (1871-1885

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    José Flávio Motta

    2008-01-01

    Full Text Available Estudamos os batismos de ingênuos registrados nas localidades paulistas de Iguape e Casa Branca entre 1871 e 1885. Nesse período, houve em Iguape o esmorecimento do dinamismo econômico assentado no cultivo de arroz destinado ao mercado interno. Já Casa Branca achava-se próxima à fronteira da expansão da lavoura cafeeira na província. Com a ênfase posta na comparação entre esses dois municípios, com vistas a explorar o condicionamento exercido por seus díspares panos de fundo econômicos, analisamos as características dos registros aludidos. Observamos a freqüência dos batizados no tempo, bem como computamos a distribuição, de acordo com a condição de legitimidade, das crianças nascidas de mães escravas após a promulgação da Lei do Ventre Livre. Acompanhamos o comportamento da defasagem temporal entre a data do nascimento e a do batismo. Avançamos, com fundamento em dois estudos de caso, um para cada uma das localidades selecionadas, algumas considerações acerca dos intervalos intergenésicos. Por fim, voltamos nossa atenção para a condição social de padrinhos e madrinhas. Mostraram-se muito expressivas, regra geral, as disparidades entre Iguape e Casa Branca.We study the baptisms of ingênuos registered in the localities of Iguape and Casa Branca, both in the province of São Paulo, in the period 1871-1885. Iguape, in those years, saw a slackening of the economic dynamism based on rice cultivation for the internal market. Casa Branca, on the other hand, was near the expansion frontier of coffee culture in the province. We emphasize the comparison between the characteristics of the registers of baptisms of ingênuos preserved for those two cities to explore the impact of their different economic contexts. We observe the frequency in time of the baptisms of children born of slave mothers after de promulgation of the Ventre-Livre Law. In addition, we compute the distribution of baptisms according to legitimacy

  9. Cloning, Expression and Characterization of Mitochondrial Manganese Superoxide Dismutase from the Whitefly, Bemisia tabaci

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    Xian-Long Gao

    2013-01-01

    Full Text Available A mitochondrial manganese superoxide dismutase from an invasive species of the whitefly Bemisia tabaci complex (Bt-mMnSOD was cloned and analyzed. The full length cDNA of Bt-mMnSOD is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. Compared with various vertebrate and invertebrate animals, the MnSOD signature (DVWEHAYY and four conserved amino acids for manganese binding (H54, H102, D186 and H190 were observed in Bt-mMnSOD. Recombinant Bt-mMnSOD was overexpressed in Escherichia coli, and the enzymatic activity of purified mMnSOD was assayed under various temperatures. Quantitative real-time PCR analysis with whiteflies of different development stages showed that the mRNA levels of Bt-mMnSOD were significantly higher in the 4th instar than in other stages. In addition, the in vivo activities of MnSOD in the whitefly were measured under various conditions, including exposure to low (4 °C and high (40 °C temperatures, transfer from a favorable to an unfavorable host plant (from cotton to tobacco and treatment with pesticides. Our results indicate that the whitefly MnSOD plays an important role in cellular stress responses and anti-oxidative processes and that it might contribute to the successful worldwide distribution of the invasive whitefly.

  10. Fitness of Encarsia sophia(Hymenoptera: Aphelinidae)parasitizing Trialeurodes vaporariorum and Bemisia tabaci (Hemiptera: Aleyrodidae)

    Institute of Scientific and Technical Information of China (English)

    Chen Luo; Tong-Xian Liu

    2011-01-01

    Fitness and efficacy of Encarsia sophia(Girault & Dodd)(Hymenoptera:Aphelinidae)as a biological control agent was compared on two species of whitefly(Hemiptera: Aleyrodidae)hosts,the relatively smaller sweetpotato whitefly,Bemisia tabaci(Gennadius)biotype 'B',and the larger greenhouse whitefly,Trialeurodes vaporariorum(Westwood).Significant differences were observed on green bean(Phaseolus vulgaris L.)in the laboratory at 27± 2℃,55% ± 5% RH,and a photoperiod of 14 : 10 h(L : D).Adult parasitoids emerging from T.vaporariorum were larger than those emerging from B.tabaci,and almost all biological parameters of E.sophia parasitizing the larger host species were superior except for the developmental times of the parasitoids that were similar when parasitizing the two host species.Furthermore,parasitoids emerging from T.vaporariorum parasitized more of these hosts than did parasitoids emerging from B.tabaci.We conclude that E.sophia reared from larger hosts had better fitness than from smaller hosts.Those from either host also preferred the larger host for oviposition but were just as effective on smaller hosts.Therefore,larger hosts tended to produce better parasitoids than smaller hosts.

  11. Foraging behavior and prey interactions by a guild of predators on various lifestages of Bemisia tabaci

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    James R. Hagler

    2004-01-01

    Full Text Available The sweetpotato whitefly, Bemisia tabaci (Gennadius is fed on by a wide variety of generalist predators, but there is little information on these predator-prey interactions. A laboratory investigation was conducted to quantify the foraging behavior of the adults of five common whitefly predators presented with a surfeit of whitefly eggs, nymphs, and adults. The beetles, Hippodamia convergens Guérin-Méneville and Collops vittatus (Say fed mostly on whitefly eggs, but readily and rapidly preyed on all of the whitefly lifestages. The true bugs, Geocoris punctipes (Say and Orius tristicolor (Say preyed almost exclusively on adult whiteflies, while Lygus hesperus Knight preyed almost exclusively on nymphs. The true bugs had much longer prey handling times than the beetles and spent much more of their time feeding (35-42% than the beetles (6-7%. These results indicate that generalist predators vary significantly in their interaction with this host, and that foraging behavior should be considered during development of a predator-based biological control program for B. tabaci.

  12. Foraging behavior and prey interactions by a guild of predators on various lifestages of Bemisia tabaci.

    Science.gov (United States)

    Hagler, James R; Jackson, Charles G; Isaacs, Rufus; Machtley, Scott A

    2004-01-01

    The sweetpotato whitefly, Bemisia tabaci (Gennadius) is fed on by a wide variety of generalist predators, but there is little information on these predator-prey interactions. A laboratory investigation was conducted to quantify the foraging behavior of the adults of five common whitefly predators presented with a surfeit of whitefly eggs, nymphs, and adults. The beetles, Hippodamia convergens Guerin-Meneville and Collops vittatus (Say) fed mostly on whitefly eggs, but readily and rapidly preyed on all of the whitefly lifestages. The true bugs, Geocoris punctipes (Say) and Orius tristicolor (Say) preyed almost exclusively on adult whiteflies, while Lygus hesperus Knight preyed almost exclusively on nymphs. The true bugs had much longer prey handling times than the beetles and spent much more of their time feeding (35-42%) than the beetles (6-7%). These results indicate that generalist predators vary significantly in their interaction with this host, and that foraging behavior should be considered during development of a predator-based biological control program for B. tabaci.

  13. Bioactivity of indigenous medicinal plants against the cotton whitefly, Bemisia tabaci.

    Science.gov (United States)

    Hammad, E Abou-Fakhr; Zeaiter, A; Saliba, N; Talhouk, S

    2014-01-01

    Forty-one methanol extracts of 28 indigenous medicinal plant species were tested for their insecticidal bioactivity against cotton whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), adults and second nymphal instars under controlled conditions. This study is within a bioprospection context, in the form of utilizing local plant species as an alternative in sustainable agriculture development. Eighteen and nine plant extracts caused a significant decrease in number of live adult and nymphal whiteflies, respectively, compared to the control. This is the first report for the potential effect on survival of insects for 22 out of 28 tested medicinal plant species. Whole plant extracts of Ranunculus myosuroudes Boiss. and Kotschy (Ranunculaceae),Achillea damascena L. (Asteraceae), and Anthemis hebronica Boiss. and Kotschy (Asteraceae) and leaf extracts of Verbascum leptostychum DC. (Scrophulariaceae) and Heliotropium rotundifolium Boiss. (Borangiaceae) caused both repellent and toxic effects against the adult and second nymphal instars, respectively. Extracts of leaves and stems of Anthemis scariosa Boiss. (Asteraceae) and Calendula palestina Pers. (Asteraceae) were found to be more bioactive against the adult and nymphal instars, respectively, than extracts of other plant parts, such as flowers. Thus, the bioactive extracts of these medicinal plants have the potential to lower whitefly populations in a comprehensive pest management program in local communities, pending cultivation of these medicinal plant species.

  14. RNA interference for the control of whiteflies (Bemisia tabaci) by oral route

    Indian Academy of Sciences (India)

    Santosh Kumar Upadhyay; K Chandrashekar; Nidhi Thakur; Praveen Chandra Verma; J Francis Borgio; Pradhyumna Kumar; Rakesh Tuli

    2011-03-01

    RNA interference (RNAi)-mediated gene silencing was explored for the control of sap-sucking pest Bemisia tabaci, commonly known as whitefly. dsRNAs and siRNAs were synthesized from five different genes – actin ortholog, ADP/ATP translocase, -tubulin, ribosomal protein L9 (RPL9) and V-ATPase A subunit. A simplified insect bioassay method was developed for the delivery of ds/siRNA through the oral route, and efficacy was evaluated. ds/siRNA caused 29–97% mortality after 6 days of feeding. Each insect ingested nearly 150 nl of insect diet per day, which contained a maximum of 6 ng of RNA. Knocking down the expression of RPL9 and V-ATPase A caused higher mortality with LC50 11.21 and 3.08 g/ml, respectively, as compared to other genes. Semi-quantitative PCR of the treated insects showed significant decrease in the level of RPL9 and V-ATPase A transcripts. siRNAs were found stable in the insect diet for at least 7 days at the room temperature. Phloem-specific expression of dsRNAs of RPL9 and V-ATPase A in transgenic plants for the protection against whiteflies might be an interesting application of this technology.

  15. The Salicylic Acid-Mediated Release of Plant Volatiles Affects the Host Choice of Bemisia tabaci

    Directory of Open Access Journals (Sweden)

    Xiaobin Shi

    2016-06-01

    Full Text Available The whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae causes serious crop losses worldwide by transmitting viruses. We have previously shown that salicylic acid (SA-related plant defenses directly affect whiteflies. In this study, we applied exogenous SA to tomato plants in order to investigate the interaction between SA-induced plant volatiles and nonviruliferous B. tabaci B and Q or B- and Q-carrying tomato yellow leaf curl virus (TYLCV. The results showed that exogenous SA caused plants to repel nonviruliferous whiteflies, but the effect was reduced when the SA concentration was low and when the whiteflies were viruliferous. Exogenous SA increased the number and quantity of plant volatiles—especially the quantity of methyl salicylate and δ-limonene. In Y-tube olfactometer assays, methyl salicylate and δ-limonene repelled the whiteflies, but the repellency was reduced for viruliferous Q. We suggest that the release of plant volatiles as mediated by SA affects the interaction between whiteflies, plants, and viruses. Further studies are needed to determine why viruliferous Q is less sensitive than nonviruliferous Q to repellent plant volatiles.

  16. Population genetic structure and secondary endosymbionts of Q Bemisia tabaci (Hemiptera: Aleyrodidae) from Greece.

    Science.gov (United States)

    Tsagkarakou, A; Mouton, L; Kristoffersen, J B; Dokianakis, E; Grispou, M; Bourtzis, K

    2012-06-01

    We investigated the molecular diversity of the major agricultural pest Bemisia tabaci and of its associated secondary endosymbionts in Greece. Analyzing mitochondrial DNA, we found that the Q1 (=Q west) is predominant. We used eight microsatellite polymorphic markers to study the genetic structure of 37 populations from mainland and insular Greece, collected on different host species from outdoor and protected crops as well as from non-cultivated plants. In some cases, gene flow was found to be low even between populations separated by just a few kilometres. Bayesian analysis identified two main genetic groups, the first encompassing populations from south Crete and the second composed of populations from north Crete, two other Aegean islands and mainland Greece. Genetic differentiation was not correlated with different host plant species or habitat, or greenhouse versus open environment populations. Gene flow significantly decreased with geographic distance, but no isolation by distance existed when only the samples from mainland Greece or only the samples from Crete were considered. The secondary symbionts Wolbachia and Hamiltonella were present at high frequencies while Arsenophonus, Cardinium and Rickettsia were absent from Greek populations. Multilocus sequence typing of Wolbachia identified two Wolbachia strains. These two strains were found together in most of the populations studied but never in the same host individual. Their role on the observed population structure is discussed.

  17. Identification of the molting hormone of the sweet potato (Bemisia tabaci) and greenhouse (Trialeurodes vaporariorum) whitefly.

    Science.gov (United States)

    Gelman, Dale B; Blackburn, Michael B; Hu, Jing S

    2005-01-01

    In order to identify the whitefly molting hormone, whole body extracts of mature 4th instar and newly formed pharate adult Bemisia tabaci (Biotype B) and Trialeurodes vaporariorum were prepared and subjected to reverse phase high performance liquid chromatography (RPHPLC). Ecdysteroid content of fractions was determined by enzymeimmunoassay (EIA). The only detectable ecdysteroids that were present in significant amounts in whitefly extracts were ecdysone and 20-hydroxyecdysone. The concentrations of 20-hydroxyecdysone in B. tabaci and T. vaporariorum extracts, respectively, were 40 and 15 times greater than the concentrations of ecdysone. The identity of the two ecdysteroids was confirmed by normal phase high performance liquid chromatography (NPHPLC). When ecdysteroid content of RPHPLC fractions was assayed by radioimmunoassay (RIA), small amounts of polar ecdysteroids were also detected indicating that these ecdysteroids have a very low affinity for the antiserum used in the EIA. Ecdysteroid at 10.4 mM administered by feeding stimulated 2nd instar whitefly nymphs to molt. Based on our results, it appears that 20-hydroxyecdysone is the whitefly molting hormone.

  18. Pathogenicity of Aschersonia spp. against whiteflies Bemisia argentifolii and Trialeurodes vaporariorum.

    Science.gov (United States)

    Meekes, Ellis T M; Fransen, Joanne J; van Lenteren, Joop C

    2002-09-01

    Entomopathogenic fungi of the genus Aschersonia are specific for whitefly and scale insects. They can be used as biological control agents against silverleaf whitefly, Bemisia argentifolii and greenhouse whitefly, Trialeurodes vaporariorum. Forty-four isolates of Aschersonia spp. were tested for their ability to sporulate and germinate on semi-artificial media and to infect insect hosts. Seven isolates sporulated poorly (less than 1x10(7) conidia/dry weight) and 10 were not able to infect either of the whitefly species. Several isolates were able to produce capilliconidia. Infection level was not correlated with germination on water agar. After a selection based on spore production and infection, virulence of 31 isolates was evaluated on third instar nymphs of both whitefly species on poinsettia (Euphorbia pulcherrima). Whitefly infection levels varied between 2 and 70%, and infection percentages of B. argentifolii correlated with that of T. vaporariorum. However, mortality was higher for T. vaporariorum than for B. argentifolii, as a result of a higher 'mortality due to unknown causes.' Several isolates, among which unidentified species of Aschersonia originating from Thailand and Malaysia, A. aleyrodis from Colombia, and A. placenta from India showed high spore production on semi-artificial medium and high infection levels of both whitefly species.

  19. Suitability changes with host leaf age for Bemisia tabaci B biotype and Trialeurodes vaporariorum.

    Science.gov (United States)

    Zhang, Gui-Fen; Wan, Fang-Hao

    2012-10-01

    The suitability of tomato leaves of different ages for Bemisia tabaci (Gennadius) B biotype and Trialeurodes vaporariorum (Westwood) was characterized by development time, stage-specific survival, sex ratio, longevity, and fecundity. Three categories of leaf ages were tested (young: expanding leaves <2 wk old; mature: fully expanded, 4-5-wk-old leaves; old: fully expanded, 6-7-wk-old leaves). There was no significant variation in the duration of development of the two species among the three classes of leaf ages, but total survival and ratio of females to males on mature and old leaves were higher than on young leaves. For egg hatch, the reverse tendency was found. Longevity of both species was higher on mature than on young leaves, and fecundity during the first 2 wk of adult life was higher on mature than on young or old leaves. The B. tabaci B biotype developed faster through the quiescent fourth nymphal instar, had higher ratio of females to males, survived longer, and produced more eggs (in the first 2 wk of adult life) than T. vaporariorum on leaves of the same age; although on young leaves, B. tabaci B biotype survivorship was lower than that of T. vaporariorum. The index of host suitability of B. tabaci B biotype was higher on mature and old leaves than on young leaves. In T. vaporariorum, no such differences were found among these three leaf ages. The results could provide some cues why B. tabaci B biotype is spreading so vigorously.

  20. Feeding preference of Macrolophus caliginosus (Heteroptera: Miridae) on Bemisia tabaci and Trialeurodes vaporariorum (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Bonato, Olivier; Couton, Louise; Fargues, Jacques

    2006-08-01

    A study of predation choices of Macrolophus caliginosus Wagner (Heteroptera: Miridae) late instars and adults, when offered various developmental stages (eggs and nymphs) of the recently established whitefly Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), was made based on two preference indices. In addition, prey choices of late instars when presented with three ratios of Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) and B. tabaci at a similar developmental stage (eggs, young or late instars) were assessed. M. caliginosus preferred older nymphs of B. tabaci than any other stage. It also chose T. vaporariorum over B. tabaci, unless the latter consisted of > 75% of the available prey. These results suggested that M. caliginosus might interfere with parasitoids such as Encarsia, Eretmocerus, or Amitus spp. because all three species emerge from the host pupal case. Furthermore, in mixed infestations, M. caliginosus preference for T. vaporariorum might either negatively affect the control of B. tabaci, or, contrarily, enhance the predator population, before a B. tabaci outbreak occurs in the greenhouse.

  1. Sublethal effects of some botanical and chemical insecticides on the cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-09-01

    Full Text Available In addition to direct mortalities caused by acute concentrations of insecticides, some biological traits of target pests may be also affected by sublethal doses. The cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae is an important pest of a wide variety of agricultural crops across the world. The control of B. tabaci largely relies on wide application of chemical insecticides. In this study, we analyzed the life table parameters to evaluate the sublethal effect of three plant-derived insecticides (Fumaria parviflora (Fumariaceae, Teucrium polium (Lamiaceae, and Thymus vulgaris (Lamiaceae and two chemical insecticides (pymetrozin and neemarin on B. tabaci. The whiteflies were allowed to oviposit on plants infected with each of the five insecticides using leaf-dip method. The data were analyzed using the age-stage two-sex life table. We found significant differences in the gross reproductive rate (GRR, the net reproductive rat (R0, the intrinsic rate of increase (r and the finite rate of increase (λ of treated whiteflies compared to control. Our results showed that some biological traits of B. tabaci are affected by sub-lethal doses of the plant-derived extracts and that these effects are comparable to those of chemical insecticides. Given the detrimental effects of chemical insecticides on human, environment and non-target organisms, plant-derived insecticides may provide valuable environmentally friendly tools for pest management programs.

  2. Genetic Differentiation of Different Geographical Populations of Bemisia tabaci (Gennadius) Complex

    Institute of Scientific and Technical Information of China (English)

    CHU Dong; LIU Guo-xia; FAN Zhong-xue; TAO Yun-li; ZHANG You-jun

    2007-01-01

    Bemisia tabaci (Gennadius) is a species complex, which includes different geographical populations with genetic differentiation. The recent progress on the genetic differentiation of various geographical populations of B. tabaci complex was introduced. The genetic differentiation was further analyzed on the basis of the sequences of mtDNA COI and rDNA ITSl recorded in the world's GenBank. Five groups are defined on the basis of mtDNA COI and rDNA ITS1, including the Asia group, America group, Africa group, Australia group, and Biotype B/Mediterranean/Middle East/ Northern Africa/Biotype Ms group. There are several ungrouped geographical classifications, such as the Uganda population, Ivory Coast population, and Taiwan population. Geographical isolation may be the most important factor that contributed to the genetic differentiation of various geographical populations of B. tabaci. Many populations with biological advantages invaded new regions and caused severe economic losses within human activity. It is necessary to strengthen the research of B. tabaci biotype to prevent the spread of invaded populations and the invasion of potentially dangerous populations.

  3. RNAi-mediated resistance to whitefly (Bemisia tabaci) in genetically engineered lettuce (Lactuca sativa).

    Science.gov (United States)

    Ibrahim, Abdulrazak B; Monteiro, Tatiane R; Cabral, Glaucia B; Aragão, Francisco J L

    2017-07-15

    RNA interference (RNAi)-based transgenic technologies have evolved as potent biochemical tools for silencing specific genes of plant pathogens and pests. The approach has been demonstrated to be useful in silencing genes in insect species. Here, we report on the successful construction of RNAi-based plasmid containing an interfering cassette designed to generate dsRNAs that target a novel v-ATPase transcript in whitefly (Bemisia tabaci), an important agricultural pest in tropical and sub-tropical regions. The presence of the transgene was confirmed in T0 and T1 generations of transgenic lettuce lines, segregating in a Mendelian fashion. Seven lines were infested with whiteflies and monitored over a period of 32 days. Analysis of mortality showed that within five days of feeding, insects on transgenic plants showed a mortality rate of 83.8-98.1%. In addition, a reduced number of eggs (95 fold less) was observed in flies feeding on transgenic lettuce plants than insects on control lines. Quantitative reverse transcription PCR showed decreased expression level of endogenous v-ATPase gene in whiteflies feeding on transgenic plants. This technology is a foundation for the production of whitefly-resistant commercial crops, improving agricultural sustainability and food security, reducing the use of more environmentally aggressive methods of pest control.

  4. Comparative Morphology and Morphometry of Six Biotypes of Bemisia tabaci (Hemiptera:Aleyrodidae) from China

    Institute of Scientific and Technical Information of China (English)

    LI Jing-jing; TANG Qing-bo; BAI Run-e; LI Xiao-min; JIANG Jin-wei; ZHAI Qing; YAN Feng-ming

    2013-01-01

    Morphology and morphometry of six biotypes (B, Q, Cv, ZHJ-1, ZHJ-2 and ZHJ-3) of Bemisia tabaci (Gennadius) from China on cotton plants were studied by using microscopes. Nymphal body sizes and characters were measured and observed, especially on the 4th instar (pupal case), including the vasiform orifice, operculum, lingula, length and thickness of anterior and posterior wax margins, width of thoracic tracheal combs. Adult characters of both sexes were investigated including the body size, compound eyes, antennal segments, vasiform orifice, hind tarsi and genitals. The results indicated that differences of some morphological characters or morphometrics were significant among the six biotypes of B. tabaci in China:(1) Pupal sizes of the exotic biotypes (B and Q) were significantly larger than the indigenous biotypes with the following order as B>Q>ZHJ-1>Cv>ZHJ-3>ZHJ-2;(2) for both male and female adults, sizes of all characters investigated in the invading biotypes (B and Q), especially B, were much larger than those of the indigenous ones.

  5. Whitefly Bemisia tabaci (Homoptera: Aleyrodidae) infestation on cassava genotypes grown at different ecozones in Nigeria.

    Science.gov (United States)

    Ariyo, O A; Dixon, A G O; Atiri, G I

    2005-04-01

    Large-scale screening of cassava, Manihot esculenta Crantz, genotypes for resistance to infestation by whitefly Bemisia tabaci Gennadius, the vector of cassava mosaic geminiviruses, is limited. A range of new cassava elite clones were therefore assessed for the whitefly infestation in the 1999/2000 and 2000/2001 cropping seasons in experimental fields of International Institute of Tropical Agriculture, Ibadan, Nigeria. On each scoring day, between 0600 and 0800 hours when the whiteflies were relatively immobile, adult whitefly populations on the five topmost expanded leaves of cassava cultivars were counted. All through the 6-mo scoring period, there was a highly significant difference in whitefly infestation among the new cassava elite clones. Vector population buildup was observed in Ibadan (forest-savanna transition zone) and Onne (humid forest), 2 mo after planting (MAP). Mean infestation across cassava genotypes was significantly highest (16.6 whiteflies per plant) in Ibadan and lowest in Zaria (0.2). Generally, whitefly infestation was very low in all locations at 5 and 6 MAP. During this period, cassava genotypes 96/1439 and 91/02324 significantly supported higher infestations than other genotypes. Plants of 96/1089A and TMS 30572 supported the lowest whitefly infestation across cassava genotypes in all locations. The preferential whitefly visitation, the differences between locations in relation to whitefly population, cassava mosaic disease, and the fresh root yield of cassava genotypes are discussed.

  6. Isolation and identification of culturable bacteria from honeydew of whitefly, Bemisia tabaci (G. (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Roopa H.K.

    2014-12-01

    Full Text Available Bemisia tabaci (G. is an important pest and a vector of Gemini viruses infecting plants. During the process of feeding B. tabaci excretes honeydew which is rich in nutrients, and an excellent medium for microbial growth. Recent report proved that volatile emitted by the honeydew associated bacteria of aphid, Acyrthosiphon pisum Harris was involved in natural enemy calling. Thus understanding the honeydew associated bacteria is of paramount importance from the non-chemical method of insect pest management. In this perspective, very less information is available on bacteria associated with the honeydew excreted by B. tabaci. Therefore, in the present study we have isolated and characterized three culturable bacteria from the honeydew of B. tabaci viz. Bacillus endophyticus, Bacillus niacini and Roseomonas species by employing 16Sr DNA BLASTx analyses which revealed that both B. endophyticus and B. niacini had high similarity (>99% to the respective species, while Roseomonas sp. showed only 95% similarity to the existing Roseomonas sp. specificity of honeydew association of Roseomonas sp. was confirmed by developing specific primers as this genus is reported from immunocompromised persons and recently from ticks and mites. The present study also indicated the possible host-plant origin of these honeydew associated bacteria.

  7. Isolation and identification of culturable bacteria from honeydew of whitefly, Bemisia tabaci (G.) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    H K, Roopa; K B, Rebijith; R, Asokan; Mahmood, Riaz; N K, Krishna Kumar

    2014-12-01

    Bemisia tabaci (G.) is an important pest and a vector of Gemini viruses infecting plants. During the process of feeding B. tabaci excretes honeydew which is rich in nutrients, and an excellent medium for microbial growth. Recent report proved that volatile emitted by the honeydew associated bacteria of aphid, Acyrthosiphon pisum Harris was involved in natural enemy calling. Thus understanding the honeydew associated bacteria is of paramount importance from the non-chemical method of insect pest management. In this perspective, very less information is available on bacteria associated with the honeydew excreted by B. tabaci. Therefore, in the present study we have isolated and characterized three culturable bacteria from the honeydew of B. tabaci viz. Bacillus endophyticus, Bacillus niacini and Roseomonas species by employing 16Sr DNA BLASTx analyses which revealed that both B. endophyticus and B. niacini had high similarity (> 99%) to the respective species, while Roseomonas sp. showed only 95% similarity to the existing Roseomonas sp. specificity of honeydew association of Roseomonas sp. was confirmed by developing specific primers as this genus is reported from immunocompromised persons and recently from ticks and mites. The present study also indicated the possible host-plant origin of these honeydew associated bacteria.

  8. Feasible sampling plan for Bemisia tabaci control decision-making in watermelon fields.

    Science.gov (United States)

    Lima, Carlos Ho; Sarmento, Renato A; Pereira, Poliana S; Galdino, Tarcísio Vs; Santos, Fábio A; Silva, Joedna; Picanço, Marcelo C

    2017-05-23

    The silverleaf whitefly Bemisia tabaci is one of the most important pests of watermelon fields worldwide. Conventional sampling plans are the starting point for the generation of decision-making systems of integrated pest management programs. The aim of this study was to determine a conventional sampling plan for B. tabaci in watermelon fields. The optimal leaf for B. tabaci adult sampling was the 6(th) most apical leaf. Direct counting was the best pest sampling technique. Crop pest densities fitted the negative binomial distribution and had a common aggregation parameter (Kcommon ). The sampling plan consisted of evaluating 103 samples per plot. This sampling plan was conducted for 56 min, costing US$ 2.22 per sampling and with a 10% maximum evaluation error. The sampling plan determined in this study can be adopted by farmers because it enables the adequate evaluation of B. tabaci populations in watermelon fields (10% maximum evaluation error) and is a low-cost (US$ 2.22 per sampling), fast (56 min per sampling) and feasible (because it may be used in a standardized way throughout the crop cycle) technique. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  9. Diversity of secondary endosymbionts among different putative species of the whitefly Bemisia tabaci.

    Science.gov (United States)

    Bing, Xiao-Li; Ruan, Yong-Ming; Rao, Qiong; Wang, Xiao-Wei; Liu, Shu-Sheng

    2013-04-01

    Endosymbionts are important components of arthropod biology. The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex composed of ≥ 28 putative species. In addition to the primary endosymbiont Portiera aleyrodidarum, six secondary endosymbionts (S-endosymbionts), Hamiltonella, Rickettsia, Wolbachia, Cardinium, Arsenophonus and Fritschea, have been identified in B. tabaci thus far. Here, we tested five of the six S-endosymbiont lineages (excluding Fritschea) from 340 whitely individuals representing six putative species from China. Hamiltonella was detected only in the two exotic invaders, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED). Rickettsia was absent in Asia II 1 and MED, scarce in Asia II 3 (13%), but abundant in Asia II 7 (63.2%), China 1 (84.7%) and MEAM1 (100%). Wolbachia, Cardinium and Arsenophonus were absent in the invasive MEAM1 and MED but mostly abundant in the native putative species. Furthermore, phylogenetic analyses revealed that some S-endosymbionts have several clades and different B. tabaci putative species can harbor different clades of a given S-endosymbiont, demonstrating further the complexity of S-endosymbionts in B. tabaci. All together, our results demonstrate the variation and diversity of S-endosymbionts in different putative species of B. tabaci, especially between invasive and native whiteflies.

  10. HOST SPECIFIC MOLECULAR VARIATIONS IN BEMISIA TABACI (G. AS REVEALED BY USING MITOCHONDRIAL AND RIBOSOMAL MARKER

    Directory of Open Access Journals (Sweden)

    R. ELLANGO

    2014-06-01

    Full Text Available Bemisia tabaci is globally important pest and also vector of Gemini viruses on various economically important crops worldwide. Presently there are lots of debates going on the species status and cryptic nature of this species which is complex as challenging. Therefore, in this study we analysed the genetic diversity of B. tabaci (18 samples collected on various host plants. The diversity analysis was performed using two well known markers such as mitochondrial COI gene and the ribosomal ITS1. The phylogenetic trees were constructed separately for two dataset using Neighbor-Joining method. Our result confirmed presence of four putative species of B. tabaci such as Asia I, Asia II 1, Asia II 5 and Asia II 8 in India. The Asia I genetic group found most widely distributed and shows relatively polyphagus, which has mtCOI consensus sequence identity of 84.32% to 86.76% with Asia II sub groups. Our work has shown the genetic boundary of B. tabaci which helped in understanding host specificity across Karnataka, India.

  11. Bemisia tabaci (Hemiptera: Aleyrodidae) nymphal feeding in cotton (Gossypium hirsutum) leaves

    Institute of Scientific and Technical Information of China (English)

    CHANG-CHI CHU; DENNIS A. MARGOSAN; JAMES S. BUCKNER; THOMAS P. FREEMAN; THOMAS J. HENNEBERRY

    2007-01-01

    We used brightfield electron microscopy (BEM), differential interference contrast microscopy (DICM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM) to investigate the stylet pathways of Bemisia tabaci during nymphal feeding behavior in cotton leaves beginning with penetration of the abaxial leaf surface and ending with stylers in sieve tubes in phloem tissues. Most nymphal stylets within salivary sheaths penetrating leaf tissues made complex turns and developed more than one salivary sheath branch before ending in sieve tubes. The external morphology of the salivary sheaths and their routes between and through leaf cells are described during the present study. Results showed the presence of the stylet within the sieve tubes. B. tabaci nymphs may remove stylets and feed in different sieve tubes.Ten short movies showing the progression of the stylet penetrations from adaxial surface to the sieve tubes are attached to Figures 8-15. The report and movies can be viewed from the internet. Download the movies to a local drive in your compute rfirs tfor fast upload. The movies are posted on theweb sitehttp ://www.ars.usda.gov/Services/docs.htm? docid= 14629.The movies can be used as a teaching aid in biology classes.

  12. Odor, Not Performance, Dictates Bemisia tabaci's Selection between Healthy and Virus Infected Plants

    Science.gov (United States)

    Chen, Gong; Su, Qi; Shi, Xiaobin; Liu, Xin; Peng, Zhengke; Zheng, Huixin; Xie, Wen; Xu, Baoyun; Wang, Shaoli; Wu, Qingjun; Zhou, Xuguo; Zhang, Youjun

    2017-01-01

    Although, insect herbivores are generally thought to select hosts that favor the fitness of their progeny, this “mother-knows-best” hypothesis may be challenged by the presence of a plant virus. Our previous study showed that the whitefly, Bemisia tabaci, the obligate vector for transmitting Tomato yellow leaf curl virus (TYLCV), preferred to settle and oviposit on TYLCV-infected rather than healthy host plant, Datura stramonium. The performances of B. tabaci larvae and adults were indeed improved on virus-infected D. stramonium, which is consistent with “mother-knows-best” hypothesis. In this study, B. tabaci Q displayed the same preference to settle and oviposit on Tomato spotted wilt virus (TSWV)-infected host plants, D. stramonium and Capsicum annuum, respectively. As a non-vector of TSWV, however, insect performance was impaired since adult body size, longevity, survival, and fecundity were reduced in TSWV infected D. stramonium. This appears to be an odor-mediated behavior, as plant volatile profiles are modified by viral infection. Infected plants have reduced quantities of o-xylene and α-pinene, and increased levels of phenol and 2-ethyl-1-hexanol in their headspace. Subsequent behavior experiments showed that o-xylene and α-pinene are repellant, while phenol and 2-ethyl-1-hexanol are attractive. This indicates that the preference of B. tabaci for virus-infected plants is modulated by the dynamic changes in the volatile profiles rather than the subsequent performances on virus-infected plants. PMID:28360861

  13. Diversity of secondary endosymbionts among different putative species of the whitefly Bemisia tabaci

    Institute of Scientific and Technical Information of China (English)

    Xiao-Li Bing; Yong-Ming Ruan; Qiong Rao; Xiao-Wei Wang; Shu-Sheng Liu

    2013-01-01

    Endosymbionts are important components of arthropod biology.The whitefly Bemisia tabaci (Gennadius) (Hemiptera:Aleyrodidae) is a cryptic species complex composed of≥28 putative species.In addition to the primary endosymbiont Portiera aleyrodidarum,six secondary endosymbionts (S-endosymbionts),Hamiltonella,Rickettsia,Wolbachia,Cardinium,Arsenophonus and Fritschea,have been identified in B.tabaci thus far.Here,we tested five of the six S-endosymbiont lineages (excluding Fritschea) from 340 whitely individuals representing six putative species from China.Hamiltonella was detected only in the two exotic invaders,Middle East-Asia Minor 1 (MEAM 1) and Mediterranean (MED).Rickettsia was absent in Asia Ⅱ 1 and MED,scarce in Asia Ⅱ 3 (13%),but abundant in Asia Ⅱ 7 (63.2%),China 1 (84.7%) and MEAM1 (100%).Wolbachia,Cardinium and Arsenophonus were absent in the invasive MEAM 1 and MED but mostly abundant in the native putative species.Furthermore,phylogenetic analyses revealed that some S-endosymbionts have several clades and different B.tabaci putative species can harbor different clades of a given S-endosymbiont,demonstrating further the complexity of S-endosymbionts in B.tabaci.All together,our results demonstrate the variation and diversity of S-endosymbionts in different putative species ofB.tabaci,especially between invasive and native whiteflies.

  14. Transcriptome analysis of host-associated differentiation in Bemisia tabaci (Hemiptera: Aleyrodidae

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    Wen eXie

    2014-12-01

    Full Text Available Host-associated differentiation is one of the driving forces behind the diversification of phytophagous insects. In this study, host induced transcriptomic differences were investigated in the sweetpotato whitefly Bemisia tabaci, an invasive agricultural pest worldwide. Comparative transcriptomic analyses using coding sequence (CDS, 5’ and 3’ untranslated regions (UTR showed that sequence divergences between the original host plant, cabbage, and the derived hosts, including cotton, cucumber and tomato, were 0.11%-0.14%, 0.19%-0.26% and 0.15%-0.21%, respectively. In comparison to the derived hosts, 418 female and 303 male transcripts, respectively, were up-regulated in the original cabbage strain. Among them, 17 transcripts were consistently up-regulated in both female and male whiteflies originated from the cabbage host. Specifically, two ESTs annotated as Cathepsin B or Cathepsin B-like genes were significantly up-regulated in the original cabbage strain, representing a transcriptomic response to the dietary challenges imposed by the host shifting. Results from our transcriptome analysis, in conjunction with previous reports documenting the minor changes in their reproductive capacity, insecticide susceptibility, symbiotic composition and feeding behavior, suggest that the impact of host-associated differentiation in whiteflies is limited. Furthermore, it is unlikely the major factor contributing to their rapid range expansion/invasiveness.

  15. Quantitative resistance against Bemisia tabaci in Solanum pennellii:Genetics and metabolomics

    Institute of Scientific and Technical Information of China (English)

    Alejandro F Lucatti; Sjaak van Heusden; Colette Broekgaarden; Roland Mumm; Marcel Dicke; Ben Vosman

    2016-01-01

    The whitefly Bemisia tabaci is a serious threat in tomato cultivation worldwide as all varieties grown today are highly susceptible to this devastating herbivorous insect. Many accessions of the tomato wild relative Solanum pennellii show a high resistance towards B. tabaci. A mapping approach was used to elucidate the genetic background of whitefly-resistance related traits and associated biochemical traits in this species. Minor quantitative trait loci (QTLs) for whitefly adult survival (AS) and oviposition rate (OR) were identified and some were confirmed in an F2BC1 population, where they showed increased percentages of explained variance (more than 30%). Bulked segregant analyses on pools of whitefly-resistant and-susceptible F2 plants enabled the identification of metabolites that correlate either with resistance or susceptibility. Genetic mapping of these metabolites showed that a large number of them co-localize with whitefly-resistance QTLs. Some of these whitefly-resistance QTLs are hotspots for metabolite QTLs. Although a large number of metabolite QTLs correlated to whitefly resistance or suscepti-bility, most of them are yet unknown compounds and further studies are needed to identify the metabolic pathways and genes involved. The results indicate a direct genetic correla-tion between biochemical-based resistance characteristics and reduced whitefly incidence in S. pennellii.

  16. Host plants and natural enemies of Bemisia tabaci (Hemiptera: Aleyrodidae)in China

    Institute of Scientific and Technical Information of China (English)

    Shao-Jian Li; Xia Xue; Muhammad Z.Ahmed; Shun-Xiang Ren; Yu-Zhou Du; Jian-Hui Wu; Andrew G.S.Cuthbertson; Bao-Li Qiu

    2011-01-01

    The sweetpotato whitefly,Bemisia tabaci,has been a destructive pest in China for over the past two decades.It is an extremely polyphagous insect,being recorded feeding on hundreds of host plants around the world.Potential host plants and natural enemies of B.tabaci in the south,southeast,middle,north and northwest of China were investigated during the last decade.In total 361 plant species from 89 families were recorded in our surveys.Plants in the families Compositae,Cruciferae,Cucurbitaceae,Solanaceae and Leguminosae were the preferred host species for B.tabaci,which therefore suffered much damage from this devastating pest due to their high populations.In total,56 species of parasitoids,54 species of arthropod predators and seven species of entomopathogenic fungi were recorded in our surveys.Aphelinid parasitoids from Encarsia and Eretmocerus genera,lady beetles and lacewings in Coleoptera and Neuroptera were found to be the dominant arthropod predators of B.tabaci in China.The varieties of host plant,their distribution and the dominant species of natural enemies of B.tabaci in different regions of China are discussed.

  17. Sequential sampling of Bemisia tuberculata (Bondar, 1923 (Hemiptera: Aleyrodidae on cassava crop

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    ANTONIO S. SILVA

    2014-06-01

    Full Text Available Estimate efficiently of the whitefly population (Bemisia tuberculata Bondar in cassava, to assist in decision making of pest control is one of the advantages of sequential sampling plans. Therefore, the objective of this study was to determine a sequential sampling plan according to two methods of pest management, using biological and/or chemical control. Samples were obtained in a commercial field of 2.500,00 m2, divided into 100 plots. The visualization method was used for sampling of the upper leaves by counting the number of adults. In total 15 samples were taken weekly from January to April 2012. The spatial distribution model which best fit to the behavior of B. tuberculata adults was the negative binomial distribution. Levels adapted for biological and chemical control were five and twenty adults per plant, respectively. Sampling plans resulted in two decisions for each proposed method. Thus, for population control the upper limit was defined as S1 = 4.2056 + 2.1540n (biological and S1 = 20.219 + 10.4306n (chemical; and the lower limit where the pest control is not recommended was defined by S0 = -4.2056 + 2.1540n (biological and S0 = -20.219 + 10.4306n (chemical. Sequential sampling estimated the maximum number of sample units necessary for decision-making of three samples with 1.34 adults for biological control and 3.85 sample units with 7.39 adult pests for chemical control.

  18. Development of Bemisia tabaci (Gennadius,1889 biotype B on Lycopersicon spp. genotypes

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    Marilene Fancelli

    2002-01-01

    Full Text Available Whiteflies are phytophagous insects, whose nymphs and adults suck the phloem sap, causing direct damage due to host plant weakness. In tomato (Lycopersicon spp. crops, they are important vectors of limiting fitoviruses. The objective of this study was to determine the effects of Lycopersicon spp. genotypes on Bemisia tabaci (Gennadius, 1889 biotype B development under greenhouse conditions. The evaluated genotypes were LA462 (L. peruvianum, LA716 (L. pennellii, LA1584 (L. pimpinellifolium, LA1609 (L. peruvianum, LA1739 (L. hirsutum, P25 (L. esculentum, PI134417 (L. hirsutum f. glabratum and Santa Clara (L. esculentum. LA716 was non-preferred for oviposition by the whitefly, which suggests an antixenotic effect. LA1584 showed an antibiotic resistance because nymphal survival was reduced and nymphal developmental time was increased. Antixenotic resistance was observed in LA1739 and PI134417, based on a reduction of oviposition. PI134417 also reduced nymphal survival, which suggests an antibiotic effect, but LA1739 was suitable for insect development. LA1609 was highly preferred for oviposition, however it reduced insect survival. P25 and Santa Clara (L. esculentum were highly preferred for oviposition.

  19. Lack of resistance development in Bemisia tabaci to Isaria fumosorosea after multiple generations of selection

    Science.gov (United States)

    Gao, Tianni; Wang, Zhaolei; Huang, Yü; Keyhani, Nemat O.; Huang, Zhen

    2017-01-01

    The emergence of insecticide resistant insect pests is of significant concern worldwide. The whitefly, Bemisia tabaci, is an important agricultural pest and has shown incredible resilience developing resistance to a number of chemical pesticides. Entomopathogenic fungi such as Isaria fumosorosea offer an attractive alternative to chemical pesticides for insect control, and this fungus has been shown to be an effective pathogen of B. tabaci. Little is known concerning the potential for the development of resistance to I. fumosorosea by B. tabaci. Five generations of successive survivors of B. tabaci infected by I. fumosorosea were assayed with I. fumosorosea. No significant differences in susceptibility to I. fumosorosea, number of ovarioles, or ovipostioning were seen between any of the generations tested. Effects of I. fumosorosea and cell-free ethyl acetate fractions derived from the fungus on the B. tabaci fat body, ovary, and vitellogenin were also investigated. These data revealed significant deformation and degradation of ovary tissues and associated vitellogenin by the fungal mycelium as well as by cell-free ethyl acetate fungal extracts. These data indicate the lack of the emergence of resistance to I. fumosorosea under the conditions tested and demonstrate invasion of the insect reproductive tissues during fungal infection. PMID:28230074

  20. Bioactivity of indigenous medicinal plants against the cotton whitefly, Bemisia tabaci.

    Science.gov (United States)

    Hammad, E Abou-Fakhr; Zeaiter, A; Saliba, N; Talhouk, S

    2014-01-01

    Forty-one methanol extracts of 28 indigenous medicinal plant species were tested for their insecticidal bioactivity against cotton whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), adults and second nymphal instars under controlled conditions. This study is within a bioprospection context, in the form of utilizing local plant species as an alternative in sustainable agriculture development. Eighteen and nine plant extracts caused a significant decrease in number of live adult and nymphal whiteflies, respectively, compared to the control. This is the first report for the potential effect on survival of insects for 22 out of 28 tested medicinal plant species. Whole plant extracts of Ranunculus myosuroudes Boiss. and Kotschy (Ranunculaceae), Achillea damascena L. (Asteraceae), and Anthemis hebronica Boiss. and Kotschy (Asteraceae) and leaf extracts of Verbascum leptostychum DC. (Scrophulariaceae) and Heliotropium rotundifolium Boiss. (Borangiaceae) caused both repellent and toxic effects against the adult and second nymphal instars, respectively. Extracts of leaves and stems of Anthemis scariosa Boiss. (Asteraceae) and Calendula palestina Pers. (Asteraceae) were found to be more bioactive against the adult and nymphal instars, respectively, than extracts of other plant parts, such as flowers. Thus, the bioactive extracts of these medicinal plants have the potential to lower whitefly populations in a comprehensive pest management program in local communities, pending cultivation of these medicinal plant species.

  1. Characterization of a newly discovered symbiont of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Bing, Xiao-Li; Yang, Jiao; Zchori-Fein, Einat; Wang, Xiao-Wei; Liu, Shu-Sheng

    2013-01-01

    Bemisia tabaci (Hemiptera: Aleyrodidae) is a species complex containing >28 cryptic species, some of which are important crop pests worldwide. Like many other sap-sucking insects, whiteflies harbor an obligatory symbiont, "Candidatus Portiera aleyrodidarum," and a number of secondary symbionts. So far, six genera of secondary symbionts have been identified in B. tabaci. In this study, we report and describe the finding of an additional bacterium in the indigenous B. tabaci cryptic species China 1 (formerly known as B. tabaci biotype ZHJ3). Phylogenetic analysis based on the 16S rRNA and gltA genes showed that the bacterium belongs to the Alphaproteobacteria subdivision of the Proteobacteria and has a close relationship with human pathogens of the genus Orientia. Consequently, we temporarily named it Orientia-like organism (OLO). OLO was found in six of eight wild populations of B. tabaci China 1, with the infection rate ranging from 46.2% to 76.8%. Fluorescence in situ hybridization (FISH) of B. tabaci China 1 in nymphs and adults revealed that OLOs are confined to the bacteriome and co-occur with "Ca. Portiera aleyrodidarum." The vertical transmission of OLO was demonstrated by detection of OLO at the anterior pole end of the oocytes through FISH. Quantitative PCR analysis of population dynamics suggested a complex interaction between "Ca. Portiera aleyrodidarum" and OLO. Based on these results, we propose "Candidatus Hemipteriphilus asiaticus" for the classification of this symbiont from B. tabaci.

  2. Investigating contact toxicity of Geranium and Artemisia essential oils on Bemisia tabaci Gen.

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    Fatemeh Yarahmadi

    2013-04-01

    Full Text Available Objective: Sweet potato whitefly, Bemisia tabaci Gen. (B. tabaci, is one of the most important pests of various greenhouse crops in Iran. Nowadays, chemical insecticides are broadly used for control of the pests that causes risk to consumer's health. For the first time, contact toxicity of Pelargonium roseum Andrews and Artemisia sieberi Besser essential oils on B. tabaci and its possible application against the whitefly was evaluated in 2012. Materials and Methods: Essential oil with concentrations of 2500, 1250, 125, and 12 ppm were used. Infested leaves of greenhouse cucumber were treated by mentioned concentrations. After 24 hours, mortality of B. tabaci was recorded and compared after correcting by Abbot's formula. Results: Results showed that all concentrations of the essential oil could significantly reduce population of B. tabaci compared with the control treatment. Phytotoxicity of the treated leaves were recorded after 24, 48, and 72 hours and compared with the control. Concentrations of 2500, 1250, and 125 ppm caused severe phytotoxicity on greenhouse cucumber leaves and therefore are not suitable for greenhouse application. Phytotoxicity of 12 ppm was relatively low. Conclusions: This data implicated suitable protective effects of the essential oils to the pest infestation. Therefore, essential oils distillated from Geranium and Artemisia could be applied to control B. tabaci in greenhouse cucumber at V/V 12 ppm.

  3. Aphid-induced Defences in Chilli Affect Preferences of the Whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Saad, Khalid A; Mohamad Roff, M N; Hallett, Rebecca H; Idris, A B

    2015-09-03

    The sweetpotato whitefly (WF), Bemisia tabaci, is a major pest that damages a wide range of vegetable crops in Malaysia. WF infestation is influenced by a variety of factors, including previous infestation of the host plant by other insect pests. This study investigated the effects of previous infestation of host chilli plants by the green peach aphid (Myzus persicae) on the olfactory behavioural response of B. tabaci, using free-choice bioassay with a Y-tube olfactometer. We analysed volatile organic compounds (VOCs) emitted by non-infested and M. persicae-infested chilli plants using solid-phase microextraction and gas chromatography-mass spectrometry. Our results showed that female WFs preferred non-infested to pre-infested plants. Collection and analysis of volatile compounds emitted by infested plants confirmed that there were significant increases in the production of monoterpenes (cymene; 1,8-cineole), sesquiterpenes (β-cadinene, α-copaene), and methyl salicylate (MeSA) compared to non-infested plants. Our results suggest that host plant infestation by aphids may induce production of secondary metabolites that deter B. tabaci from settling on its host plants. These results provide important information for understanding WF host selection and dispersal among crops, and also for manipulating WF behaviour to improve IPM in chilli.

  4. Acyl sugars and whitefly (Bemisia tabaci) resistance in segregating populations of tomato genotypes.

    Science.gov (United States)

    Dias, D M; Resende, J T V; Marodin, J C; Matos, R; Lustosa, I F; Resende, N C V

    2016-04-07

    The wild tomato, Solanum pennellii, is an important source of resistance genes against tomato pests. This resistance is due to the presence of acyl sugars (AS), which are allelochemicals that have negative effects on arthropod pests. There are no commercially available tomato cultivars that exhibit significant levels of resistance to arthropod pests. Therefore, this study evaluated resistance to whitefly (Bemisia tabaci) in F2 and F2RC1 tomato genotypes with high AS levels from a cross between Solanum lycopersicum 'Redenção' and the S. pennellii accession, LA-716. Plants were exposed to B. tabaci biotype B at the pre-flowering stage. In both generations, there were significant, negative correlations between AS content and oviposition preference and nymph development. Whitefly exhibited a lower preference for oviposition and produced fewer nymphs in genotypes with high AS levels and the wild parent S. pennellii than in the low AS-level genotypes and Redenção cultivar, demonstrating that the breeding program was effective in transferring resistance to the F2 and F2RC1 generations. RVTA-2010-pl#31 and RVTA-2010-pl#94 in the F2 population are promising genotypes that produced materials with high AS levels in the F2RC1 generation (RVTA-2010-31-pl#177 and RVTA-2010-94-pl#381).

  5. Cloning, expression and characterization of mitochondrial manganese superoxide dismutase from the Whitefly, Bemisia tabaci.

    Science.gov (United States)

    Gao, Xian-Long; Li, Jun-Min; Wang, Yong-Liang; Jiu, Min; Yan, Gen-Hong; Liu, Shu-Sheng; Wang, Xiao-Wei

    2013-01-07

    A mitochondrial manganese superoxide dismutase from an invasive species of the whitefly Bemisia tabaci complex (Bt-mMnSOD) was cloned and analyzed. The full length cDNA of Bt-mMnSOD is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. Compared with various vertebrate and invertebrate animals, the MnSOD signature (DVWEHAYY) and four conserved amino acids for manganese binding (H54, H102, D186 and H190) were observed in Bt-mMnSOD. Recombinant Bt-mMnSOD was overexpressed in Escherichia coli, and the enzymatic activity of purified mMnSOD was assayed under various temperatures. Quantitative real-time PCR analysis with whiteflies of different development stages showed that the mRNA levels of Bt-mMnSOD were significantly higher in the 4th instar than in other stages. In addition, the in vivo activities of MnSOD in the whitefly were measured under various conditions, including exposure to low (4 °C) and high (40 °C) temperatures, transfer from a favorable to an unfavorable host plant (from cotton to tobacco) and treatment with pesticides. Our results indicate that the whitefly MnSOD plays an important role in cellular stress responses and anti-oxidative processes and that it might contribute to the successful worldwide distribution of the invasive whitefly.

  6. Lack of resistance development in Bemisia tabaci to Isaria fumosorosea after multiple generations of selection

    Science.gov (United States)

    Gao, Tianni; Wang, Zhaolei; Huang, Yü; Keyhani, Nemat O.; Huang, Zhen

    2017-02-01

    The emergence of insecticide resistant insect pests is of significant concern worldwide. The whitefly, Bemisia tabaci, is an important agricultural pest and has shown incredible resilience developing resistance to a number of chemical pesticides. Entomopathogenic fungi such as Isaria fumosorosea offer an attractive alternative to chemical pesticides for insect control, and this fungus has been shown to be an effective pathogen of B. tabaci. Little is known concerning the potential for the development of resistance to I. fumosorosea by B. tabaci. Five generations of successive survivors of B. tabaci infected by I. fumosorosea were assayed with I. fumosorosea. No significant differences in susceptibility to I. fumosorosea, number of ovarioles, or ovipostioning were seen between any of the generations tested. Effects of I. fumosorosea and cell-free ethyl acetate fractions derived from the fungus on the B. tabaci fat body, ovary, and vitellogenin were also investigated. These data revealed significant deformation and degradation of ovary tissues and associated vitellogenin by the fungal mycelium as well as by cell-free ethyl acetate fungal extracts. These data indicate the lack of the emergence of resistance to I. fumosorosea under the conditions tested and demonstrate invasion of the insect reproductive tissues during fungal infection.

  7. Biological Invasions of Geminiviruses: Case Study of TYLCV and Bemisia tabaci in Reunion Island

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    Jean-Michel Lett

    2012-12-01

    Full Text Available In the last 20 years, molecular ecology approaches have proven to be extremely useful to identify and assess factors associated with viral emerging diseases, particularly in economically and socially important tropical crops such as maize (maize streak disease and cassava (cassava mosaic disease. Molecular ecology approaches were applied in Reunion Island to analyze the epidemic of tomato yellow leaf curl disease, which has been affecting the island since the end of the 1990s. Before the invasive biotype B (currently known as Middle East-Asia Minor 1 cryptic species of Bemisia tabaci spread across the world, Reunion Island (South West Indian Ocean only hosted an indigenous biotype of B. tabaci, Ms (currently known as Indian Ocean cryptic species. Wild hybrids between invasive and indigenous species were subsequently characterized over multiple generations. Endosymbiont analysis of the hybrid population indicated that matings were non-random. Similarly, while no indigenous begomoviruses have ever been reported on Reunion Island, the two main strains of one of the most damaging and emerging plant viruses in the world, the Mild and Israel strains of the Tomato yellow leaf curl virus (TYLCV-Mld and TYLCV-IL, were introduced in 1997 and 2004 respectively. While these introductions extensively modified the agricultural landscape of Reunion Island, they also provided an invaluable opportunity to study the ecological and genetic mechanisms involved in biological invasion and competition.

  8. Factors affecting population dynamics of maternally transmitted endosymbionts in Bemisia tabaci.

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    Huipeng Pan

    Full Text Available While every individual of Bemisia tabaci (Hemiptera: Aleyrodidae harbors the primary symbiont (P-symbiont Portiera, the infection frequencies of the six secondary symbionts (S-symbionts including Hamiltonella, Arsenophonus, Cardinium, Wolbachia, Rickettsia and Fritschea vary greatly among different populations. To characterize the factors influencing the infection dynamics of the six S-symbionts in B. tabaci, gene-specific PCR were conducted to screen for the presence of the P-symbiont Portiera and the six S-symbionts in 61 (17 B and 44 Q biotypes field populations collected from different plant species and locations in China. All individuals of the 61 populations hosted the P-symbiont Portiera, but none of them harbored Arsenophonus and Fritschea. The presence and infection rates of Hamiltonella, Cardinium, Rickettsia, Wolbachia and their co-infections Rickettsia + Hamiltonella (RH, Rickettsia + Cardinium (RC, Hamiltonella + Cardinium (HC and Rickettsia + Hamiltonella + Cardinium (RHC varied significantly among the 61 field populations; and the observed variations can be explained by biotypes, sexes, host plants and geographical locations of these field populations. Taken together, at least three factors including biotype, host plant and geographical location affect the infection dynamics of S-symbionts in B. tabaci.

  9. AÇÕES EM EDUCAÇÃO AMBIENTAL: UMA CONTRIBUIÇÃO PARA O PROCESSO DE EMPODERAMENTO DA COMUNIDADE DE PEDRA BRANCA, SANTA TEREZINHA, BA

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    Bruna Moreno Lins

    2015-04-01

    Full Text Available Este trabalho foi realizado por professores e alunos da Universidade Estadual de Feira de Santana (UEFS conjuntamente com moradores da comunidade de Pedra Branca, organizado a partir de entrevistas abertas, de oficinas e palestras. A proposta contemplou a realização de ações de Educação Ambiental (EA onde a questão norteadora foi a geração e disposição de resíduos sólidos domiciliares, bem como sua reutilização para produção de peças artesanais. A análise das entrevistas nos permitiu formar uma ideia da visão de lixo da comunidade, que foi trabalhada através de oficinas e palestras, onde foi discutida a problemática do lixo em comunidades rurais, transmitidas informações sobre os processos de reciclagem e reutilização de materiais, e sobre consumo consciente. Novas ações em EA serão realizadas para dar continuidade aos trabalhos educativos, buscando reforçar as ações anteriores, bem como estimular as pessoas a se perceberem como parte integrante do meio ambiente. Palavras-chave: Extensão Universitária, Reutilização de Materiais, Educação para Sustentabilidade.   Environmental Education Actions: Contributions for the Empowerment of Pedra Branca Community, Santa Terezinha, Bahia Abstract: This work was carried out by students and professors of Universidade Estadual de Feira de Santana (UEFS with people from Pedra Branca village, Bahia State. The study was developed through open interviews, workshops and lectures. The project included environmental education actions on which the guiding question was the generation and disposal of solid waste in rural areas as well as their reuse for production of handicrafts. The interviews analysis allowed us to form an idea about the vision of trash in the community, which was covered in the workshops and lectures on which we discussed the problem of waste in rural communities and transmitted information about the recycling process and conscious consumption. News actions

  10. Virulence of entomopathogenic fungi against nymphs of Bemisia tabaci (Genn. (Hemiptera: AleyrodidaeVirulência de fungos entomopatogênicos a ninfas de Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae

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    Alfredo Gouvea

    2011-12-01

    Full Text Available The objective of this study was to evaluate the pathogenicity and virulence of isolates of Beauveria bassiana (Unioeste 47 and Unioeste 57, Metarhizium anisopliae (Unioeste 43 and Esalq 09 and Isaria sp. (IBCB 367 a d IBCB 394 against Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae. Suspensions of the isolates (1.0 × 109 conidia/mL were sprayed on third instar nymphs on cabbage leaves. It was performed four replications, each one with 20 insects, for each treatment. The control consisted of sterile distilled water + Tween® 80 (0.01%. The number of killed nymphs was evaluated during seven days, and then they were kept in a moist chamber. To estimate the median lethal concentration (LC50, isolates suspensions of 1.0 × 105, 1.0 × 106, 1.0 × 107, 1.0 × 108 and 1.0 × 109 conidia/mL were sprayed on third instar nymphs. The number of nymphs with confirmed mortality was evaluated. The isolates B. bassiana Unioeste 47 (84.1% and Isaria sp. IBCB 367 (98.6% did not differ significantly, causing the highest mortalities. However, the isolate M. anisopliae Esalq 09 caused the lower confirmed mortality (23.2%. The LC50 of the B. bassiana isolates varied from 1.8 × 105 and 4.1 × 105 conidia/mL (Unioeste 57 and Unioeste 47, respectively. Among the isolates of M. anisopliae, Esalq 09 presented the highest LC50 value (7.8 × 108 conidia/mL, whereas Unioeste 43 presents the lowest (4,3 × 105 conidia/mL. The Isaria sp. isolates presented LC50 of 2.5 × 105 and 3.1 × 105 conidia/mL (IBCB 367 and IBCB 394, respectively. Therefore, B. bassiana Unioeste 47 e Isaria sp. IBCB 367 isolates had potential to B. tabaci control and for future field studies.O objetivo deste trabalho foi avaliar a patogenicidade e a virulência dos isolados de Beauveria bassiana (Unioeste 47 e Unioeste 57, Metarhizium anisopliae (Unioeste 43 e Esalq 09 e Isaria sp. (IBCB 367 e IBCB 394 a Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae. Suspensões dos isolados (1,0 × 109 conídios/ m

  11. First report and differential colonization of Passiflora species by the B biotype of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Endson S.; Vieira, Maria L.C. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Genetica]. E-mail: esnunes@carpa.ciagri.usp.br; mlcvieir@esalq.usp.br; Brown, Judith K. [University of Arizona, Tucson, AZ (United States). Dept. of Plant Sciences]. E-mail: jbrown@Ag.arizona.edu; Moreira, Adriana G.; Rezende, Jorge A.M. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola]. E-mails: agmoreir@esalq.usp.br; amrezen@esalq.usp.br; Watson, Gillian [California Dept. of Food and Agriculture, Sacramento, CA (United States)]. E-mail: gwatson@cdfa.ca.gov; Lourencao, Andre L. [Instituto Agronomico, Campinas, SP (Brazil). Centro de Pesquisa e Desenvolvimento de Fitossanidade]. E-mail: andre@iac.sp.gov.br; Piedade, Sonia M.S. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Ciencias Exatas]. E-mail: jsoniamsp@esalq.usp.br

    2008-11-15

    This note is the first report of Bemisia tabaci (Gennadius) biotype B colonizing passionvine in Brazil. We examined the colonization of nine Passiflora species by a wild B type population under greenhouse conditions. P. amethystina Mikan was the most preferred species for oviposition and colonization, whereas P. suberosa L., P. coriacea Juss. and two commercially cultivated species, P. alata Curtis and P. edulis Sims f. flavicarpa Degener, were mostly uncolonised. P. morifolia Mast., P. cincinnata Mast., P. foetida L. and P. caerulea L. showed intermediate levels of colonization. Such differential colonization might suggest some degree of resistance by certain Passiflora species or oviposition preference by B. tabaci. (author)

  12. Occurrence of Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae parasitizing Bemisia tabaci (Genn. biotype B (Hemiptera: Aleyrodidae in Brazil

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    André Luiz Lourenção

    2014-06-01

    Full Text Available The parasitism of Bemisia tabaci (Genn. biotype B nymphs on cotton plants was observed during a research on resistance of cotton genotypes to this whitefly. The experiment was set in a greenhouse at the Experimental Station of the Instituto Agronômico (IAC, in Campinas, São Paulo State, Brazil. Samples of the parasitized nymphs were collected and maintained in laboratory to monitor the parasitism and obtain the adult parasitoids. A total of 129 adult parasitoids were obtained, including one Encarsia inaron (Walker, 13 En. lutea (Masi, and 115 Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae. This is the first report of Er. mundus in Brazil.

  13. Only the B biotype of Bemisia tabaci is present on vegetables in São Paulo State, Brazil

    OpenAIRE

    Rocha, Kelly Cristina Gonçales [UNESP; Marubayashi,Julio Massaharu; Navas-Castillo, Jesús; Yuki, Valdir Atsushi; Wilcken, Carlos Frederico [UNESP; Pavan,Marcelo Agenor; Krause-Sakate, Renate

    2011-01-01

    Bemisia tabaci (Genn.) is one of the most important pests in cultivated areas of vegetables and ornamental crops around the world. Based on the mitochondrial cytochrome oxidize I (mtCOI) sequence, there is evidence that B. tabaci should be considered a cryptic species complex of 11 groups containing 24 species. Two of the groups, Middle East-Asia Minor 1 and Mediterranean include biotypes B and Q, respectively. In this study we evaluated the mtCOI sequence of B. tabaci populations collected i...

  14. Análise da freqüência de trombofilia em pacientes com atrofia branca de Milian Frequency analysis of thrombophilia in patients with atrophie blanche

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    Aline Donati Jorge

    2007-02-01

    Full Text Available FUNDAMENTOS - Atrofia branca de Milian ou vasculopatia livedóide é entidade clinicopatológica rara, cuja patogênese não é completamente compreendida. OBJETIVOS - Avaliar casos de atrofia branca de Milian para verificar a prevalência de diversas trombofilias. MATERIAL E MÉTODOS - Quatorze pacientes foram submetidos a exames laboratoriais incluindo pesquisa de fator V (Leiden, protrombina mutante, dosagem de antitrombina, proteína S e C, pesquisa de anticorpos anticardiolipina e anticoagulante lúpico, dosagem de homocisteína e pesquisa da mutação da metilenotetraidrofolatoredutase. RESULTADOS - Dos nove doentes cujos critérios de inclusão foram preenchidos para análise da freqüência de trombofilia, foram encontrados quatro com fatores relacionados à trombofilia: deficiência da antitrombina (um caso, deficiência da proteína S (um caso, mutação da metilenotetraidrofolatoredutase com hiperhomocisteinemia (um caso e presença de anticorpo anticardiolipina (um caso. CONCLUSÃO - Apesar de este estudo não apresentar casuística que possibilite a comparação com a população geral, os dados sugerem a presença de eventos geradores de trombofilia nesses doentes, contribuindo para adoção sistemática de um protocolo de investigação de trombofilia nos doentes portadores de vasculopatia livedóide no Brasil.INTRODUCTION: Atrophie blanche, or livedoid vasculopathy, is a rare clinicopathological entity of unknown etiology. A "thrombo-occlusive process" theory has recently been accepted. OBJECTIVES: To search the presence of several thrombophilic abnormalities in patients with livedoid vasculopathy. METHODS: Fourteen patients were evaluated and tested for factor V Leiden, prothrombin 20210G/A variant, antithrombin, C and S proteins, anticardiolipin and lupus anticoagulant antibodies, homocysteine and methylenetetrahydrofolate reductase mutation. RESULTS: Nine patients met all criteria to be included in the analysis and four of

  15. Densidade mineral óssea vertebral e femoral de 724 mulheres brancas brasileiras: influência da idade e do peso corporal

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    Lewin S.

    1997-01-01

    Full Text Available OBJETIVO. Estudar a densidade mineral óssea (BMD vertebral (L2-L4 e femoral (colo do fêmur de mulheres brancas, normais. MATERIAL E MÉTODO. Mediu-se o BMD de 724 mulheres (40-79 kg; 20-69 anos de idade por dual-energy x-ray absorptiometry e analisaram-se os dados em função da idade e peso corporal (PC. RESULTADOS. As mulheres mais leves (40-49 kg atingiram o BMD máximo (BMDm vertebral e femoral aos 30-39 anos de idade, enquanto as mais pesadas (60-79kg apresentaram BMDm aos 20 anos. No fêmur, houve uma correlação significativa entre BMDm e PC (r=0,97 , p<0,001; slope=0,72%/kg. Em L2-L4, apenas as mulheres com 40-49kg apresentaram BMDm menor do que as demais (p<0,001. A diminuição do BMD vertebral foi mais intensa (-8,3 vs. -5,7%/década e iniciou mais cedo (quarta vs. quinta década nas mulheres pesando 40-59kg do que nas pesando 60-79kg. A diminuição do BMD femoral iniciou logo após o BMDm ser atingido e, até os 69 anos, as mulheres mais pesadas apresentaram um decréscimo 5,3% menor do que aquelas pesando 40-49kg. O BMD vertebral das mulheres brasileiras foi praticamente o mesmo de uma população norte-americana previamente descrita. CONCLUSÕES. 1 O BMD vertebral e femoral das brasileiras estudadas comportou-se, em função da idade, de forma semelhante a de outras populações brancas; 2 havendo o cuidado de corrigir o PC, o BMD das mulheres brasileiras é comparável ao de mulheres norte-americanas; e 3 o PC é importante na aquisição e diminuição da massa óssea, além de influenciar a relação BMD-idade.

  16. Eficácia de atrativos alimentares na captura de moscas-das-frutas em pomar de citros Attractiveness of food baits to the fruit flies in citrus orchard

    Directory of Open Access Journals (Sweden)

    Adalton Raga

    2006-01-01

    Full Text Available As moscas-das-frutas (Diptera: Tephritoidea são importantes pragas de frutas cítricas no Estado de São Paulo, principalmente Anastrepha fraterculus (Wied. e Ceratitis capitata (Wied.. O objetivo deste estudo foi medir a eficiência dos atrativos alimentares para monitoramento de moscas-das-frutas, em pomar de citros. O delineamento experimental adotado foi de blocos ao acaso com cinco tratamentos e cinco repetições. O ensaio foi instalado em 30/9/2003 e desenvolvidopor nove semanas. Os atrativos testados foram: proteínas hidrolisadas comerciais Bio Anastrepha, Isca Mosca e Aumax®, todas diluídas em água a 5%; melaço a 7% isoladamente e melaço a 7% em mistura com suco de laranja a 10%. Foram utilizados semanalmente, 400mL da solução atrativa por frasco plástico McPhail instalado na copa de laranjeiras da variedade 'Pêra Rio'. As soluções eram renovadas semanalmente, ocasião em que os adultos eram coletados e çevados ao laboratório para contagem, sexagem e identificação. Foram capturados 1.821 adultos de Tephritoidea, sendo 892 de Anastrepha spp., 731 de C. capitata e 198 de Neosilba spp. Para essas espécies, as proteínas Bio Anastrepha e Isca Mosca foram altamente eficientes e semelhantes entre si, capturando 44,5% e 41,3% dos adultos de Tephritidae respectivamente. Não houve diferença entre as espécies de Tephritidae analisadas por sexo capturadas em Bio Anastrepha, Aumax® e melaço. Aumax®, melaço isoladamente e melaço + suco de laranja atraíram apenas 4,6%, 1,3% e 1,2% do total de adultos de Tephritidae, respectivamente. Melaço isoladamente e melaço com suco de laranja foram mais eficazes na atratividade de Zaprionus indianus (Gupta (Diptera: Drosophilidae.Fruit flies (Diptera: Tephritoidea are key pests in citrus production in the State of São Paulo, Brazil, mainly Anastrepha fraterculus (Wied. and Ceratitis capitata (Wied.. The objective of this study was to evaluate food baits to monitor fruit fly

  17. Diversidade de moscas frugívoras (Diptera, Tephritoidea) em áreas de matas decídua e ciliar no Pantanal sul-mato-grossense, Brasil Diversity of frugivorous flies (Diptera, Tephritoidea) in areas of decidual and riparian forests in South Pantanal, Brazil

    OpenAIRE

    Edima Ramos Minzão; Manoel Araécio Uchôa-Fernandes

    2008-01-01

    O conhecimento da diversidade de espécies de moscas nos ecossistemas é importante para subsidiar na escolha de métodos ecologicamente corretos para o controle de tefritóideos (Tephritidae e Lonchaeidae) pragas. O objetivo deste trabalho foi avaliar a diversidade de tefritóideos e seus padrões populacionais em áreas de matas decídua e ciliar. As moscas foram capturadas em armadilhas McPhail com atrativo alimentar em duas reservas florestais do município de Corumbá-MS, de agosto de 2003 a agost...

  18. Avaliação de atrativos alimentares utilizados no monitoramento de mosca-das-frutas em pessegueiro na lapa- PR Food attractants used in the monitoring of fruit flies in peach trees in lapa, Paraná (PR, Brazil

    Directory of Open Access Journals (Sweden)

    Lino Bittencourt Monteiro

    2007-04-01

    Full Text Available As moscas-das-frutas do gênero Anastrepha são uma praga-chave na cultura do pessegueiro no Paraná. Atrativos alimentares foram testados para determinar a sua eficiência no monitoramento de moscas-das-frutas capturadas em frascos caça-moscas McPhail. O experimento foi conduzido por três anos, sendo que, em 2002, foram testados como atrativo o suco de uva da marca Maguari®, o hidrolisado enzimático de proteína da marca BioAnastrepha® e o vinagre da marca Chemin Agrin®. Nos dois anos seguintes, o vinagre foi substituído pelo composto protéico hidrolisável da marca Torula®. As substâncias atrativas à base de proteína foram as mais eficientes na captura de Anastrepha spp., e as capturas ocorreram antecipadas em relação ao suco de uva. De acordo com os resultados, recomendam-se atrativos à base de proteína para monitoramento de Anastrepha spp em pessegueiro, na Lapa.Fruit flies of Anastrepha genus are a key pest in peach trees in Paraná. Food attractants were tested to determine their efficiency in monitoring fruit flies captured in McPhail fly traps. The experiment was conducted over a period of three years. In 2002 the following attractors were tested: Maguari® brand grape juice, BioAnastrepha® brand hydrolyzed enzymatic protein and Chemin Agrin® vinegar. Over the next two years, the vinegar was replaced by Torula® hydrolyzed protein compound. Protein-based attractants were the most efficient in trapping Anastrepha spp. and captured flies earlier comparing to grape juice. According to the results, the use of protein-based attractants for monitoring Anastrepha spp in the Lapa peach trees was recommended.

  19. Pre shipping dip treatments using soap, natural oils, and Isaria fumosorosea: potential biopesticides for mitigating the spread of whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) invasive insects on ornamental plants

    Science.gov (United States)

    The whitefly Bemisia tabaci (Hemiptera: Aleyodidae) is an invasive insect pest affecting different crops including vegetables, fruits, cereals, and ornamentals. The efficacy of some products such as commercial soap, natural oils and Preferal® (based on the entomopathogenic fungus Isaria fumosorosea ...

  20. Asymmetric consequences of host plant occupation on the competition between the whiteflies Bemisia tabaci cryptic species MEAM1 and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae)

    DEFF Research Database (Denmark)

    Zhang, Gui-Fen; Lövei, Gabor L; Hu, Man

    2014-01-01

    BACKGROUND: The two common whitefly species, Bemisia tabaci (Gennadius) MEAM1 and Trialeurodes vaporariorum (Westwood), often co-occur on their host plants. The effect of host plant occupation by one species on later-arriving conspecific individuals or on the other competing species was examined...

  1. The draft genome of whitefly Bemisia tabaci MEAM1, a global crop pest, provides novel insights into virus transmission, host adaptation, and insecticide resistance

    Science.gov (United States)

    Whiteflies are among the most important agricultural pests. They have a broad range of host plants and exceptional ability to transmit a large number of plant viruses, and can rapidly evolve insecticide resistance. Here we present a high-quality draft genome of the whitefly, Bemisia tabaci. Comparat...

  2. Repellency of mustard (Brassica juncea) and arugula (Eruca sativa) plants, and plant oils against the sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an economic complex of at least 36 cryptic species, comprising a highly polyphagous and serious pest of vegetable, fiber and ornamental crops. Sustainable alternative measures such as cultural controls can be effective ...

  3. Comparative transcriptome analysis in Bemisia tabaci in response to tomato yellow leaf curl virus and development of ribonucleic acid interference to manage whitefly-transmitted viruses

    Science.gov (United States)

    The whitefly, Bemisia tabaci transmits over 300 plant viruses, with the majority of them belonging to the Begomovirus genus. Begomoviruses are obligately transmitted to a wide range of agriculture crops, resulting in the loss of billions of dollars annually, while jeopardizing food security worldwid...

  4. Transcriptome analysis reveals a comprehensive insect resistance response mechanism in cotton to infestation by the phloem feeding insect Bemisia tabaci (whitefly)

    Science.gov (United States)

    The whitefly (Bemisia tabaci) causes tremendous damage to cotton production worldwide. However, very limited information is available about how plants perceive and defend themselves from this destructive pest. In this study, the transcriptomics differences between two cotton cultivars that exhibit e...

  5. Transcriptome analysis of Bemisia tabaci during tomato yellow leaf curl virus acquisition and ribonucleic acid interference to manage whitefly-transmitted viruses

    Science.gov (United States)

    Over 300 viruses are transmitted by the whitefly, Bemisia tabaci, with 90% of them belonging to the genus, Begomovirus. Begomoviruses are obligately transmitted by whiteflies to a wide range of agriculture crops, resulting in billions of dollars lost annually, while jeopardizing food security worldw...

  6. En boca cerrada no entran moscas : significado social, rasgos pragmáticos y desautomatización de las paremias de CALLAR en alemán y español

    OpenAIRE

    Mellado Blanco, Carmen

    2016-01-01

    El objeto de estudio de este trabajo son el significado y comportamiento textual del proverbio alemán Reden ist Silber, Schweigen ist Gold ("El habla es plata, el silencio es oro") y de su equivalente español En boca cerrada no entran moscas. El objetivo principal es comparar las respectivas funciones pragmáticas que presentan, así como el tipo de modificaciones a las que están sometidos en el discurso. Para ello se tiene en cuenta la teoría de Wulf & Oesterreicher sobre "conceptional scriptu...

  7. A check list of necrophagous flies (Diptera: Calyptratae from urban area in Medellín, Colombia Lista de moscas necrófagas (Diptera: Calyptratae del área urbana del municipio de Medellín, Colombia

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    Jorge Alberto Salazar-Ortega

    2012-06-01

    Full Text Available An updated checklist of necrophagous flies (Diptera, Calyptratae occurring in the urban area of Medellín-Colombia is presented. 27 species belonging to 4 families are reported. Data were obtained from field work and recent bibliography references.Se presenta una lista actualizada de moscas necrófagas (Diptera, Calyptratae presentes en el área urbana del municipio de Medellín. Se registran 27 especies incluidas en cuatro familias. Los datos se obtuvieron a partir de recolectas en campo y referencias bibliográficas.

  8. Evaluation of Resistance of Cucumber Cultivars to the Vegetable Leafminer (Liriomyza sativae Blanchard (Diptera: Agromyzidae in Greenhouse Evaluación de Resistencia de Cultivares de P epino a la Mosca Minadora (Liriomyza sativae Blanchard (Diptera: Agromyzidae en Invernadero

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    Moslem Basij

    2011-09-01

    Full Text Available The leafminer, Liriomyza sativae Blanchard, is distributed around the world and is an important pest of vegetables and ornamentals. Given the resistance potential of the leafminer to current insecticides, the use of resistant plant cultivars and parasitoids could be effective integrated pest management (IPM strategies against it. Cucumber (Cucumis sativus L. is a preferred host for this insect. Seventeen cultivars of cucumber have been evaluated to study resistance mechanisms to L. sativae. All cucumber cultivars were evaluated in screening tests in greenhouse with indices such as the number of leafminer stings, the number of larval mines, the proportion of larval mines to leafminer stings, and the rate of injury. Significant differences (p La mosca minadora, Liriomyza sativae Blanchard, se ha distribuido por el mundo en recientes años y es una plaga importante de vegetales y plantas ornamentales. La resistencia potencial de la mosca minadora a insecticidas corrientes, el uso de cultivares resistentes, y parasitoides podrían ser estrategias efectivas en su manejo integrado de plagas (IPM. El pepino (Cucumis sativus L. es un huésped preferido por este insecto. Diecisiete cultivares de pepino fueron evaluados para estudiar los mecanismos de resistencia a L. sativae, en pruebas de screening en invernadero usando índices tales como número de marcas hechas por la mosca, número de galerías larvales, proporción entre galerías larvales y marcas hechas por la mosca, y tasa de daño. Se observaron diferencias significativas (p < 0,01 entre cultivares, así como correlaciones significativas entre los índices evaluados. Los cultivares de pepino se clasificaron por el método cluster basado en todos los caracteres medidos en cuatro grupos: susceptible, semi susceptible, semi resistente, y resistente. Los ensayos de resistencia a antibiosis de los cultivares se condujeron en cámara de crecimiento y se evaluaron con algunos índices biológicos de

  9. 'Aroeira-branca' [Lithraea molleoides (Vell. Engl. - Anacardiaceae] seed quality evaluation by the X-ray test Avaliação da qualidade de sementes de aroeira-branca [Lithraea molleoides (Vell. Engl. - Anacardiaceae] por meio de raios-X

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    Cibele Ferreira Machado

    2003-01-01

    Full Text Available 'Aroeira-branca', an arboreal species of great ecological and economic importance, is seed propagated and presents limitations with respect to the availability of methods for seed quality evaluation. The X-ray test has been considered of potential value because it is accurate, quick and nondestructive. In this context, the objective of this work was to verify the possibility of this test to detect damage and/or abnormalities in aroeira-branca embryos, in an attempt to correlate these anomalies to germination. Four seed lots were collected in different locations in the southern region of the State of Minas Gerais, Brazil, during 2001. The X-ray test consisted of submitting 100 seeds/lot to radiation (exposure of seeds to radiation of 13 kV/5 minutes and classifying them according to embryo/embryo cavity proportions of 0, A aroeira-branca, espécie arbórea de grande importância ecológica e econômica, multiplica-se por sementes, as quais têm apresentado limitações quanto à disponibilidade de métodos para a avaliação da qualidade. O teste de raios-X tem se destacado por ser um método rápido, preciso e não destrutivo. Neste contexto, o presente trabalho foi realizado com o objetivo de verificar a possibilidade de uso do teste de raios-X na detecção de danos e ou anormalidades em embriões de aroeira-branca, bem como associá-los à germinação. Foram utilizados quatro lotes de sementes colhidas em áreas da região sul de Minas Gerais, no ano de 2001. Cem sementes/lote foram submetidas ao teste de raios-X, que consistiu na radiografia (condições de exposição à radiação: 13 kV/5 minutos e classificação das sementes baseada na proporção do embrião em relação à cavidade embrionária, de 0, < 50, 50-75 e 100%, sendo a última classe dividida quanto à morfologia do embrião, em normal e anormal. Em seguida, foi conduzido o teste de germinação, visando detectar possíveis correspondências entre a anatomia das sementes e

  10. REVISITANDO O PEGMATITO ALTO SERRA BRANCA, MUNICÍPIO DE PEDRA LAVRADA (PB: MAPEAMENTO GEOLÓGICO, ASPECTOS DE CAMPO E ZONEAMENTO MINERAL

    Directory of Open Access Journals (Sweden)

    Lauro Montefalco Santos

    2016-01-01

    Full Text Available Nas adjacências do município de Pedra Lavrada, (Paraíba, ocorrem uma série de corpos pegmatíticos, os quais compõe a Província Pegmatítica da Borborema. Compondo um grupo de pegmatitos economicamente importantes pela abundante ocorrência de minerais na região, destaca-se entre esses o Pegmatito Alto Serra Branca. Este pegmatito ocorre encaixado em xistos da Formação Seridó, sendo influenciado por zonas de cisalhamento locais dúcteis relacionadas ao Lineamento Patos e por fraturas de atitudes variáveis. Mapeamento geológico de detalhe,  revelou que este corpo ocorre de maneira zonada, sendo definidas as zonas: i contato, ii intermediária externa, iii intermediária interna e núcleo de quartzo. Estas zonas definem ocorrências preferenciais de minerais de valor econômico, como turmalinas e apatitas na nas zonas próximas  a borda e cassiterita  nas porções mais internas. Os dados obtidos nesta pesquisa sugerem que esta rocha corresponde a um pegmatito heterogêneo alojado ao longo de tenshion gashes em um evento regional de injeção de corpos pegmatíticos na Província Borborema.

  11. Aspectos institucionais e urbanos para o desenvolvimento local do município de Pedra Branca do Amapari/Amapá

    Directory of Open Access Journals (Sweden)

    Adalberto Carvalho Ribeiro

    2010-12-01

    Full Text Available Normal 0 false false false O presente artigo tem como propósito refletir sobre fenômenos institucionais recentes que vem acontecendo no município de Pedra Branca do Amaparí vislumbrando a possibilidade de um planejamento urbano participativo para o desenvolvimento local no município. O procedimento metodológico tem como principio a pesquisa exploratória (Gil, 1991 a partir do método histórico (Lakatos, 1991 e estatístico quali/ quantitativo (Gil, 1991. Os principais pressupostos teóricos utilizados foram Buarque (2002, Ferrari Jr (2004, Oliveira (2004, Pontes (2007, e Zapata (2001.  Os resultados apontam para um conjunto de novos fenômenos que vem ocorrendo em PBA a partir de 2004, criando novas institucionalidades, bem como para um intenso fluxo migratório, falta de regularização fundiária, crescimento econômico revigorado com o “novo” ciclo minerário, mas com um modelo de gestão pública ainda precário. Assim a necessidade de construção do plano diretor a partir de metodologias participativas pode ser uma boa oportunidade para mitigar, de forma mais democrática, os níveis de desenvolvimento local. PALAVRAS-CHAVE: Planejamento Urbano Participativo, Desenvolvimento Local, Pequena Cidade.

  12. Conservation of predatory arthropods in cotton: role of action thresholds for Bemisia tabaci (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Naranjo, S E; Ellsworth, P C; Chu, C C; Henneberry, T J

    2002-08-01

    Studies were conducted in 1994 and 1995 to examine the effects of a range of action thresholds for managing Bemisia tabaci (Gennadius) Biotype B (= B. argentifolii Bellows & Perring) with insecticides in cotton on populations of arthropod predators in Imperial Valley, CA, and Maricopa, AZ. Application of insecticides significantly reduced population densities of spiders, Geocoris punctipes (Say), G. pallens (Stål), Orius tristicolor (White), Nabis alternatus Parshley, Zelus renardii Kolenati, Hippodamia convergens Guerin-Méneville, Spanogonicus albofasciatus (Reuter), Drapetis sp., and Chrysoperla carnea Stephens in one or both years and sites compared with untreated controls. Use of higher B. tabaci thresholds conserved some species and groups relative to lower thresholds. Stepwise regression analyses indicated that reductions in predator populations were generally influenced more strongly by the timing of the first insecticide application than by the total number of sprays necessary to maintain suppression of the pest below any given action threshold. A predation index, which weights the importance of each predator species based on their known frequency of predation on B. tabaci and another key pest, Pectinophora gossypiella (Saunders), was developed and analyzed. Patterns were similar to results based on changes in abundance alone, but the index generally revealed less severe effects of insecticides on overall predator function. The current action threshold for conventional insecticidal control of B. tabaci in Arizona and southern California is five adults per leaf. Results here suggest that predator conservation may be enhanced by raising the initial threshold to delay the first application or initially using more selective materials such as insect growth regulators.

  13. Identification of three major Bemisia tabaci biotypes in China based on morphological and DNA polymorphisms

    Institute of Scientific and Technical Information of China (English)

    Baoli Qiu; Yanping Chen; Li Liu; Weilu Peng; Xiaoxi Li; Yuzhou Du; Shunxiang Ren

    2009-01-01

    The sweet potato whitefly, Bemisia tabaci, is a complex species, and many of its biotypes are important agricultural pests. The B and Q biotypes are invasive and coexist with the native Cv biotype on vegetable and ornamental crops in China. In this study, these three bio-types were identified based on their morphological characteristics, RAPD-PCR analysis, and DNA sequences of the COl gene. The ante-rior and posterior wax fringes of the B, Q, and Cv biotypes significantly differed from each other. Based on this morphological characteristic, the three biotypes can easily be distinguished in greenhouses and fields. Genomic DNA RAPD-PCR band patterns also revealed differences between these biotypes using the H16 primer. The B biotype has three bright DNA bands between 250 and 600 bp, the Q biotype only has one bright band at ~300 bp, while the Cv biotype has no band between 250 and 500 bp. Both the Cv and Q biotypes have two bright bands at ~750 and 1000 bp while the B biotype has only one band at ~1000 bp. Based on the COI gene, the genetic identity between B and Cv, B and Q, and Q and CV was 85.8%, 94.7%, and 86.0%, respectively. The MP tree indicated that the phylogenetic relationship between the B and Q biotypes is much closer than that between the B and Cv or the Q and Cv biotypes. The uses of the morphological, RAPD-PCR, and DNA sequencing methods in biotype identification of B. tabaci are discussed.

  14. Bean yellow disorder virus: Parameters of transmission by Bemisia tabaci and host plant range

    Institute of Scientific and Technical Information of China (English)

    German Martín; Isabel Maria Cuadrado; Dirk Janssen

    2011-01-01

    Bean yellow disorder virus(BnYDV)was recently identified as the first crinivirus(family Closteroviridae)that infects members of the family Leguminosae.It was first observed during the autumn of 2003,causing heavy losses in French bean (Phaseolus vulgaris L.)grown commercially in Spain.The virus is transmitted by the sweetpotato whitefly,Bemisia tabaci(Hemiptera:Aleyrodidae)Q-biotype,and disease symptoms resemble nutritional disorders consisting of interveinal mottling and yellowing in leaves,combined with stiffness or brittleness,and are typically produced on the middle to lower parts of the plant.Transmission experiments showed that 50% and 100% of B.tabaci adults acquired the virus after a feeding period of 3 and 7 h,respectively.Viruliferous whiteflies infected 66% and 100% of P.vulgaris plants after a feeding period of 12 and 24 h,respectively.The transmission efficiency of single whiteflies was 37% and persistence of BnYDV in the vector lasted up to 2 weeks with a half-life of 9 days.BnYDV was transmitted to P.vulgaris,Pisum sativum L.,Lens culinaris Medik.,and Vicia faba L.,but not to Vigna unguiculata L.,Glycine max(L.) Merr.,Cicer arietum L.,and to crop species belonging to families of the Solanaceae and Cucurbitaceae.No virus was detected in field samples collected from 30 different species from Boraginaceae,Asteraceae,Geraniaceae,Lamiaceae,Leguminosae,Malvaceae,Scrophulariaceae,Thymelaeaceae and Verbenaceae.The restricted host range and efficient management of crops regarding whitefly infestation may be key elements in the control of BnYDV.

  15. Lack of fitness costs associated with acetamiprid resistance in Bemisia tabaci (Hemiptera: Aleyrodidae).

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    Basit, Muhammad; Sayyed, Ali H; Saeed, Shafqat; Saleem, Mushtaq A

    2012-08-01

    Sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is a devastating pest that can cause severe damage to a range of crops by direct feeding and by plant virus transmission. Because of indiscriminate use of insecticides, this whitefly has developed resistance to several insecticides, including neonicotinoids. Our objectives were to determine fitness components affected by acetamiprid resistance in B. tabaci. Assay results showed that selection with acetamiprid had removed heterozygotes from the field population because the survival rate of the resistant population was significantly greater than that of the field population at a very high dose. Comparison of various life traits between the acetamiprid-selected (Aceta-SEL) population and three other populations showed that the numbers of eggs laid by acetamiprid Aceta-SEL population were significantly lower compared with that of other populations but that the proportions of eggs hatched were significantly higher. However, the time taken by nymphal stages of the Aceta-SEL population to develop was significantly higher than that of the susceptible populations. The intrinsic rate of increase, net reproductive rate, mean generation time, and doubling time of Aceta-SEL was significantly higher than Lab-PK and UNSEL populations, but the growth index was similar for all populations. The growth index and high intrinsic value of Aceta-SEL population suggest that the resistance allele may not have detrimental impact. The lack of fitness costs in B. tabaci could promote the rapid development of resistance to acetamiprid and other neonicotinoids. This resistance could threaten the sustainability of whitefly management program on genetically engineered cotton (Gossypium hirsutum L.) where neonicotinoids are being sprayed to manage sucking pests in the field.

  16. Acylsucrose-producing tomato plants forces Bemisia tabaci to shift its preferred settling and feeding site.

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    Maria Jose Rodríguez-López

    Full Text Available BACKGROUND: The whitefly Bemisia tabaci (Genn. causes dramatic damage to plants by transmitting yield-limiting virus diseases. Previous studies proved that the tomato breeding line ABL 14-8 was resistant to B. tabaci, the vector of tomato yellow leaf curl disease (TYLCD. This resistance is based on the presence of type IV glandular trichomes and acylsucrose production. These trichomes deter settling and probing of B. tabaci in ABL 14-8, which reduces primary and secondary spread of TYLCD. METHODOLOGY/PRINCIPAL FINDINGS: Whitefly settlement preference was evaluated on the adaxial and abaxial leaf surfaces of nearly-isogenic tomato lines with and without B. tabaci-resistance traits, 'ABL 14-8 and Moneymaker' respectively, under non-choice and free-choice conditions. In addition, the Electrical Penetration Graph technique was used to study probing and feeding activities of B. tabaci on the adaxial and abaxial leaf surfaces of the same genotypes. B. tabaci preferred to settle on the abaxial than on the adaxial surface of 'Moneymaker' leaves, whereas no such preference was observed on ABL 14-8 tomato plants at the ten-leaf growth stage. Furthermore, B. tabaci preferred to feed on the abaxial than on the adaxial leaf surface of 'Moneymarker' susceptible tomato plants as shown by a higher number of sustained phloem feeding ingestion events and a shorter time to reach the phloem. However, B. tabaci standard probing and feeding behavior patterns were altered in ABL 14-8 plants and whiteflies were unable to feed from the phloem and spent more time in non-probing activities when exposed to the abaxial leaf surface. CONCLUSIONS/SIGNIFICANCE: The distorted behavior of B. tabaci on ABL 14-8 protects tomato plants from the transmission of phloem-restricted viruses such as Tomato yellow leaf curl virus (TYLCV, and forces whiteflies to feed on the adaxial side of leaves where they feed less efficiently and become more vulnerable to natural enemies.

  17. Small RNAs from Bemisia tabaci are transferred to Solanum lycopersicum phloem during feeding

    Directory of Open Access Journals (Sweden)

    Paula J.M. Van Kleeff

    2016-11-01

    Full Text Available The phloem-feeding whitefly Bemisia tabaci is a serious pest to a broad range of host plants, including many economically important crops such as tomato. These insects serve as a vector for various devastating plant viruses. It is known that whiteflies are capable of manipulating host-defense responses, potentially mediated by effector molecules in the whitefly saliva. We hypothesized that, beside putative effector proteins, small RNAs (sRNA are delivered by B. tabaci into the phloem, where they may play a role in manipulating host plant defenses. There is already evidence to suggest that sRNAs can mediate the host-pathogen dialogue. It has been shown that Botrytis cinerea, the causal agent of gray mold disease, takes advantage of the plant sRNA machinery to selectively silence host genes involved in defense signaling.Here we identified sRNAs originating from B. tabaci in the phloem of tomato plants on which they are feeding. sRNAs were isolated and sequenced from tomato phloem of whitefly-infested and control plants as well as from the nymphs themselves, control leaflets and from the infested leaflets. Using stem-loop RT-PCR, three whitefly sRNAs have been verified to be present in whitefly-infested leaflets that were also present in the whitefly-infested phloem sample. Our results show that whitefly sRNAs are indeed present in tomato tissues upon feeding, and they appear to be mobile in the phloem. Their role in the host-insect interaction can now be investigated.

  18. Interspecific interactions between Bemisia tabaci biotype B and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Zhang, Gui-Fen; Li, Dong-Chao; Liu, Tong-Xian; Wan, Fang-Hao; Wang, Jin-Jun

    2011-02-01

    Bemisia tabaci (Gennadius) biotype B and Trialeurodes vaporariorum (Westwood) are invasive whitefly species that often co-occur on greenhouse-grown vegetables in northern China. Although B. tabaci biotype B has been present in China for a relatively short period of time, it has become dominant over T. vaporariorum. We studied the interspecific competitive interactions between the two species in single or mixed cultures at 24 ± 1 °C, 40 ± 5% RH, and L14:D10 h photoperiod. Female longevity on tomato was not significantly different between species, but B. tabaci reproduced 4.3 to 4.9 fold more progeny. The ratio of female to male progeny in both instances was greater for B. tabaci. When cultured on tomato, cotton, and tobacco, B. tabaci developed 0.8, 3.3, and 4.7 d earlier in single culture, and 1.8, 3.9, and 4.3 d earlier in mixed culture. B. tabaci displaced T. vaporariorum in four, five and six generations when the initial ratios of B. tabaci to T. vaporariorum were 15:15, 20:10, or 10:20 on tomato. Populations of B. tabaci were 2.3 fold higher than that of T. vaporariorum on tomato plants for seven consecutive generations in single culture. B. tabaci performed better in development, survival, fecundity, and female ratio. We conclude that B. tabaci could displace T. vaporariorum in as short as four generations in a controlled greenhouse environment when they start at equal proportions. Warmer greenhouse conditions and an increase in total greenhouse area could be contributing factors in the recent dominance of B. tabaci.

  19. Resistance of soybean genotypes to Bemisia tabaci (Genn.) Biotype B (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Vieira, S S; Bueno, A F; Boff, M I C; Bueno, R C O F; Hoffman-Campo, C B

    2011-01-01

    The silverleaf whitefly Bemisia tabaci (Genn.) biotype B has become a serious problem for soybean cultivation because it can significantly reduce soybean productivity. The use of soybean cultivars resistant to whitefly attack is an important strategy in an integrated pest management (IPM) program. This study evaluated the preference for oviposition and colonization by B. tabaci biotype B on different soybean genotypes. In the free-choice test, the genotypes studied were 'IAC 17' and 'IAC 19' as the standards for resistance and 'IAC Holambra Stwart' as the standard for susceptibility, as well as BABR01-0492, BABR01-0173, BABR01-1259, BABR01-1576, BABR99-4021HC, BABR99-4021HP, 'Barreiras', 'Conquista', 'Corisco', 'BRS Gralha', PI274454, PI227687, and PI171451. In the no-choice test, the four best genotypes selected in the free-choice test, in addition to the susceptible and resistant standards were evaluated. Our data indicated 'Barreiras' as the most resistant genotype against B. tabaci biotype B. 'BRS Gralha', which was the least attractive to whitefly adults in the free-choice test, did not show resistance to insect attack when they were confined in cages in the no-choice test. Despite the high number of eggs observed, BABR01-1576 and BABR99-4021HC showed a reduced number of nymphs, indicating antibiosis. The genotypes with a high level of resistance can be used as a tool against B. tabaci in IPM or as a source of resistance in plant-breeding programs.

  20. Gene expression profiling in the thiamethoxam resistant and susceptible B-biotype sweetpotato whitefly, Bemisia tabaci.

    Science.gov (United States)

    Xie, Wen; Yang, Xin; Wang, Shao-Ii; Wu, Qing-jun; Yang, Ni-na; Li, Ru-mei; Jiao, Xiao-guo; Pan, Hui-peng; Liu, Bai-ming; Feng, Yun-tao; Xu, Bao-yun; Zhou, Xu-guo; Zhang, You-jun

    2012-01-01

    Thiamethoxam has been used as a major insecticide to control the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Due to its excessive use, a high level of resistance to thiamethoxam has developed worldwide over the past several years. To better understand the molecular mechanisms underlying this resistance in B. tabaci, gene profiles between the thiamethoxam-resistant and thiamethoxam-susceptible strains were investigated using the suppression subtractive hybridization (SSH) library approach. A total of 72 and 52 upand down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These expressed sequence tags (ESTs) belong to several functional categories based on their gene ontology annotation. Some categories such as cell communication, response to abiotic stimulus, lipid particle, and nuclear envelope were identified only in the forward library of thiamethoxam-resistant strains. In contrast, categories such as behavior, cell proliferation, nutrient reservoir activity, sequence-specific DNA binding transcription factor activity, and signal transducer activity were identified solely in the reverse library. To study the validity of the SSH method, 16 differentially expressed genes from both forward and reverse SSH libraries were selected randomly for further analyses using quantitative realtime PCR (qRT-PCR). The qRT-PCR results were fairly consistent with the SSH results; however, only 50% of the genes showed significantly different expression profiles between the thiamethoxam-resistant and thiamethoxam-susceptible whiteflies. Among these genes, a putative NAD-dependent methanol dehydrogenase was substantially over-expressed in the thiamethoxamresistant adults compared to their susceptible counterparts. The distributed profiles show that it was highly expressed during the egg stage, and was most abundant in the abdomen of adult females.

  1. Genetic networking of the Bemisia tabaci cryptic species complex reveals pattern of biological invasions.

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    Paul De Barro

    Full Text Available BACKGROUND: A challenge within the context of cryptic species is the delimitation of individual species within the complex. Statistical parsimony network analytics offers the opportunity to explore limits in situations where there are insufficient species-specific morphological characters to separate taxa. The results also enable us to explore the spread in taxa that have invaded globally. METHODOLOGY/PRINCIPAL FINDINGS: Using a 657 bp portion of mitochondrial cytochrome oxidase 1 from 352 unique haplotypes belonging to the Bemisia tabaci cryptic species complex, the analysis revealed 28 networks plus 7 unconnected individual haplotypes. Of the networks, 24 corresponded to the putative species identified using the rule set devised by Dinsdale et al. (2010. Only two species proposed in Dinsdale et al. (2010 departed substantially from the structure suggested by the analysis. The analysis of the two invasive members of the complex, Mediterranean (MED and Middle East - Asia Minor 1 (MEAM1, showed that in both cases only a small number of haplotypes represent the majority that have spread beyond the home range; one MEAM1 and three MED haplotypes account for >80% of the GenBank records. Israel is a possible source of the globally invasive MEAM1 whereas MED has two possible sources. The first is the eastern Mediterranean which has invaded only the USA, primarily Florida and to a lesser extent California. The second are western Mediterranean haplotypes that have spread to the USA, Asia and South America. The structure for MED supports two home range distributions, a Sub-Saharan range and a Mediterranean range. The MEAM1 network supports the Middle East - Asia Minor region. CONCLUSION/SIGNIFICANCE: The network analyses show a high level of congruence with the species identified in a previous phylogenetic analysis. The analysis of the two globally invasive members of the complex support the view that global invasion often involve very small portions of

  2. Transcriptomic and proteomic responses of sweetpotato whitefly, Bemisia tabaci, to thiamethoxam.

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    Nina Yang

    Full Text Available BACKGROUND: The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae, is one of the most widely distributed agricultural pests. Although it has developed resistance to many registered insecticides including the neonicotinoid insecticide thiamethoxam, the mechanisms that regulate the resistance are poorly understood. To understand the molecular basis of thiamethoxam resistance, "omics" analyses were carried out to examine differences between resistant and susceptible B. tabaci at both transcriptional and translational levels. RESULTS: A total of 1,338 mRNAs and 52 proteins were differentially expressed between resistant and susceptible B. tabaci. Among them, 11 transcripts had concurrent transcription and translation profiles. KEGG analysis mapped 318 and 35 differentially expressed genes and proteins, respectively, to 160 and 59 pathways (p<0.05. Thiamethoxam treatment activated metabolic pathways (e.g., drug metabolism, in which 118 transcripts were putatively linked to insecticide resistance, including up-regulated glutathione-S-transferase, UDP glucuronosyltransferase, glucosyl/glucuronosyl transferase, and cytochrome P450. Gene Ontology analysis placed these genes and proteins into protein complex, metabolic process, cellular process, signaling, and response to stimulus categories. Quantitative real-time PCR analysis validated "omics" response, and suggested a highly overexpressed P450, CYP6CX1, as a candidate molecular basis for the mechanistic study of thiamethoxam resistance in whiteflies. Finally, enzymatic activity assays showed elevated detoxification activities in the resistant B. tabaci. CONCLUSIONS: This study demonstrates the applicability of high-throughput omics tools for identifying molecular candidates related to thiamethoxam resistance in an agricultural important insect pest. In addition, transcriptomic and proteomic analyses provide a solid foundation for future functional investigations into the complex molecular

  3. Genome reduction and potential metabolic complementation of the dual endosymbionts in the whitefly Bemisia tabaci.

    Science.gov (United States)

    Rao, Qiong; Rollat-Farnier, Pierre-Antoine; Zhu, Dan-Tong; Santos-Garcia, Diego; Silva, Francisco J; Moya, Andrés; Latorre, Amparo; Klein, Cecilia C; Vavre, Fabrice; Sagot, Marie-France; Liu, Shu-Sheng; Mouton, Laurence; Wang, Xiao-Wei

    2015-03-21

    The whitefly Bemisia tabaci is an important agricultural pest with global distribution. This phloem-sap feeder harbors a primary symbiont, "Candidatus Portiera aleyrodidarum", which compensates for the deficient nutritional composition of its food sources, and a variety of secondary symbionts. Interestingly, all of these secondary symbionts are found in co-localization with the primary symbiont within the same bacteriocytes, which should favor the evolution of strong interactions between symbionts. In this paper, we analyzed the genome sequences of the primary symbiont Portiera and of the secondary symbiont Hamiltonella in the B. tabaci Mediterranean (MED) species in order to gain insight into the metabolic role of each symbiont in the biology of their host. The genome sequences of the uncultured symbionts Portiera and Hamiltonella were obtained from one single bacteriocyte of MED B. tabaci. As already reported, the genome of Portiera is highly reduced (357 kb), but has kept a number of genes encoding most essential amino-acids and carotenoids. On the other hand, Portiera lacks almost all the genes involved in the synthesis of vitamins and cofactors. Moreover, some pathways are incomplete, notably those involved in the synthesis of some essential amino-acids. Interestingly, the genome of Hamiltonella revealed that this secondary symbiont can not only provide vitamins and cofactors, but also complete the missing steps of some of the pathways of Portiera. In addition, some critical amino-acid biosynthetic genes are missing in the two symbiotic genomes, but analysis of whitefly transcriptome suggests that the missing steps may be performed by the whitefly itself or its microbiota. These data suggest that Portiera and Hamiltonella are not only complementary but could also be mutually dependent to provide a full complement of nutrients to their host. Altogether, these results illustrate how functional redundancies can lead to gene losses in the genomes of the different

  4. Small RNAs from Bemisia tabaci Are Transferred to Solanum lycopersicum Phloem during Feeding

    Science.gov (United States)

    van Kleeff, Paula J. M.; Galland, Marc; Schuurink, Robert C.; Bleeker, Petra M.

    2016-01-01

    The phloem-feeding whitefly Bemisia tabaci is a serious pest to a broad range of host plants, including many economically important crops such as tomato. These insects serve as a vector for various devastating plant viruses. It is known that whiteflies are capable of manipulating host-defense responses, potentially mediated by effector molecules in the whitefly saliva. We hypothesized that, beside putative effector proteins, small RNAs (sRNA) are delivered by B. tabaci into the phloem, where they may play a role in manipulating host plant defenses. There is already evidence to suggest that sRNAs can mediate the host-pathogen dialogue. It has been shown that Botrytis cinerea, the causal agent of gray mold disease, takes advantage of the plant sRNA machinery to selectively silence host genes involved in defense signaling. Here we identified sRNAs originating from B. tabaci in the phloem of tomato plants on which they are feeding. sRNAs were isolated and sequenced from tomato phloem of whitefly-infested and control plants as well as from the nymphs themselves, control leaflets, and from the infested leaflets. Using stem-loop RT-PCR, three whitefly sRNAs have been verified to be present in whitefly-infested leaflets that were also present in the whitefly-infested phloem sample. Our results show that whitefly sRNAs are indeed present in tomato tissues upon feeding, and they appear to be mobile in the phloem. Their role in the host-insect interaction can now be investigated. PMID:27933079

  5. Implication of Bemisia tabaci heat shock protein 70 in Begomovirus-whitefly interactions.

    Science.gov (United States)

    Götz, Monika; Popovski, Smadar; Kollenberg, Mario; Gorovits, Rena; Brown, Judith K; Cicero, Joseph M; Czosnek, Henryk; Winter, Stephan; Ghanim, Murad

    2012-12-01

    The whitefly Bemisia tabaci (Gennadius) is a major cosmopolitan pest capable of feeding on hundreds of plant species and transmits several major plant viruses. The most important and widespread viruses vectored by B. tabaci are in the genus Begomovirus, an unusual group of plant viruses owing to their small, single-stranded DNA genome and geminate particle morphology. B. tabaci transmits begomoviruses in a persistent circulative nonpropagative manner. Evidence suggests that the whitefly vector encounters deleterious effects following Tomato yellow leaf curl virus (TYLCV) ingestion and retention. However, little is known about the molecular and cellular basis underlying these coevolved begomovirus-whitefly interactions. To elucidate these interactions, we undertook a study using B. tabaci microarrays to specifically describe the responses of the transcriptomes of whole insects and dissected midguts following TYLCV acquisition and retention. Microarray, real-time PCR, and Western blot analyses indicated that B. tabaci heat shock protein 70 (HSP70) specifically responded to the presence of the monopartite TYLCV and the bipartite Squash leaf curl virus. Immunocapture PCR, protein coimmunoprecipitation, and virus overlay protein binding assays showed in vitro interaction between TYLCV and HSP70. Fluorescence in situ hybridization and immunolocalization showed colocalization of TYLCV and the bipartite Watermelon chlorotic stunt virus virions and HSP70 within midgut epithelial cells. Finally, membrane feeding of whiteflies with anti-HSP70 antibodies and TYLCV virions showed an increase in TYLCV transmission, suggesting an inhibitory role for HSP70 in virus transmission, a role that might be related to protection against begomoviruses while translocating in the whitefly.

  6. Differential responses of the whitefly Bemisia tabaci symbionts to unfavorable low and high temperatures.

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    Shan, Hong-Wei; Lu, Yu-Heng; Bing, Xiao-Li; Liu, Shu-Sheng; Liu, Yin-Quan

    2014-10-01

    The whitefly Bemisia tabaci complex contains many cryptic species, of which the Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) are notorious invasive pests. In our field-collected whitefly samples, MEAM1 harbors an obligate primary symbiont "Candidatus Portiera aleyrodidarum" and two secondary symbionts, "Candidatus Hamiltonella defensa" and Rickettsia sp., whereas MED has only "Ca. Portiera aleyrodidarum" and "Ca. Hamiltonella defensa." Both "Ca. Portiera aleyrodidarum" and "Ca. Hamiltonella defensa" are intracellular endosymbionts residing in the bacteriomes, whereas Rickettsia sp. has a scattered distribution throughout the host body cavity. We examined responses of these symbionts to adverse temperatures as well as survival of the host insects. After cold treatment at 5 or 10 °C or heat treatment at 35 or 40 °C for 24 h, respectively, the infection rates of all symbionts were not significantly decreased based on diagnosis PCR. However, quantitative PCR assays indicated significant reduction of "Ca. Hamiltonella defensa" at 40 °C, and the reduction became greater as the duration increased. Compared with "Ca. Hamiltonella defensa," "Ca. Portiera aleyrodidarum" was initially less affected in the first day but then showed more rapid reduction at days 3-5. The density of Rickettsia sp. fluctuated but was not reduced significantly at 40 °C. Meanwhile, the mortality rates of the host whiteflies elevated rapidly as the duration of exposure to heat treatment increased. The differential responses of various symbionts to adverse temperatures imply complex interactions among the symbionts inside the same host insect and highlight the importance of taking the whole bacterial community into account in studies of symbioses.

  7. Molecular characterization of soluble and membrane-bound trehalases of the whitefly, Bemisia tabaci.

    Science.gov (United States)

    Wang, Jia; He, Wen-Bo; Su, Yun-Lin; Bing, Xiao-Li; Liu, Shu-Sheng

    2014-04-01

    Trehalases (Tres) have been demonstrated to be the key enzymes that are involved in various trehalose-associated physiological processes in insects. However, little attention has been devoted to the Tres in the whitefly, Bemisia tabaci. In this study, a soluble Tre (BtTre-1) and a membrane-bound Tre (BtTre-2) were cloned in the invasive cryptic species Middle East-Asia Minor 1 (MEAM1) of the whitefly B. tabaci complex. Alignment of deduced amino acids sequences of both BtTres revealed that they share common consensus regions and residues with Tres of other insect species. Levels of BtTres expression in various stages and tissues of the whitefly suggested that BtTre-2 may play a key role in trehalose catabolism during development of the whitefly, especially for oocyte development, while BtTre-1 may prevent trehalose in salivary gland from leaking and entering into plants along with saliva. Potential roles of trehalose catabolism in response to direct and/or plant-mediated indirect effects of Tomato Yellow Leaf Curl China Virus (TYLCCNV) were also detected. Whiteflies feeding on virus-infected tobacco plants showed higher BtTres expressions and accordingly higher BtTres activity but lower trehalose content than those feeding on uninfected plants. The enhanced trehalose catabolism may be beneficial to oocyte development in ovary and attenuate plant defensive responses induced by trehalose in saliva. Viruliferous and nonviruliferous whiteflies feeding on cotton, a nonhost plant for TYLCCNV, differed significantly only in trehalose content. The higher trehalose content in viruliferous whiteflies may be conducive to resisting the stress inflicted by TYLCCNV.

  8. Further insight into reproductive incompatibility between putative cryptic species of the Bemisia tabaci whitefly complex.

    Science.gov (United States)

    Qin, Li; Pan, Li-Long; Liu, Shu-Sheng

    2016-04-01

    The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), with its global distribution and extensive genetic diversity, is now known to be a complex of over 35 cryptic species. However, a satisfactory resolution of the systematics of this species complex is yet to be achieved. Here, we designed experiments to examine reproductive compatibility among species with different levels of mitochondrial cytochrome oxidase I (mtCOI) divergence. The data show that putative species with mtCOI divergence of >8% between them consistently exhibited complete reproductive isolation. However, two of the putative species, Asia II 9 and Asia II 3, with mtCOI divergence of 4.47% between them, exhibited near complete reproductive compatibility in one direction of their cross, and partial reproductive compatibility in the other direction. Together with some recent reports on this topic from the literature, our data indicates that, while divergence in the mtCOI sequences provides a valid molecular marker for species delimitation in most clades, more genetic markers and more sophisticated molecular phylogeny will be required to achieve adequate delimitation of all species in this whitefly complex. While many attempts have been made to examine the reproductive compatibility among genetic groups of the B. tabaci complex, our study represents the first effort to conduct crossing experiments with putative species that were chosen with considerations of their genetic divergence. In light of the new data, we discuss the best strategy and protocols to conduct further molecular phylogenetic analysis and crossing trials, in order to reveal the overall pattern of reproductive incompatibility among species of this whitefly complex.

  9. Biotype Characterization, Developmental Profiling, Insecticide Response and Binding Property of Bemisia tabaci Chemosensory Proteins: Role of CSP in Insect Defense

    Science.gov (United States)

    Liu, Guoxia; Ma, Hongmei; Xie, Hongyan; Xuan, Ning; Guo, Xia; Fan, Zhongxue; Rajashekar, Balaji; Arnaud, Philippe; Offmann, Bernard; Picimbon, Jean-François

    2016-01-01

    Chemosensory proteins (CSPs) are believed to play a key role in the chemosensory process in insects. Sequencing genomic DNA and RNA encoding CSP1, CSP2 and CSP3 in the sweet potato whitefly Bemisia tabaci showed strong variation between B and Q biotypes. Analyzing CSP-RNA levels showed not only biotype, but also age and developmental stage-specific expression. Interestingly, applying neonicotinoid thiamethoxam insecticide using twenty-five different dose/time treatments in B and Q young adults showed that Bemisia CSP1, CSP2 and CSP3 were also differentially regulated over insecticide exposure. In our study one of the adult-specific gene (CSP1) was shown to be significantly up-regulated by the insecticide in Q, the most highly resistant form of B. tabaci. Correlatively, competitive binding assays using tryptophan fluorescence spectroscopy and molecular docking demonstrated that CSP1 protein preferentially bound to linoleic acid, while CSP2 and CSP3 proteins rather associated to another completely different type of chemical, i.e. α-pentyl-cinnamaldehyde (jasminaldehyde). This might indicate that some CSPs in whiteflies are crucial to facilitate the transport of fatty acids thus regulating some metabolic pathways of the insect immune response, while some others are tuned to much more volatile chemicals known not only for their pleasant odor scent, but also for their potent toxic insecticide activity. PMID:27167733

  10. Bemisia tabaci: The current situation in the UK and the prospect of developing strategies for eradication using entomopathogens

    Institute of Scientific and Technical Information of China (English)

    Andrew G.S.Cuthbertson; Lisa F.Blackburn; Dominic P.Eyre; Raymond J.C.Cannon; Judith Miller; Phil Northing

    2011-01-01

    The sweetpotato whitefly,Bemisia tabaci(Gennadius)(Hemiptera: Aleyrodidae)remains a serious threat to crops worldwide.The damaging B-biotype is of specific economic concern because it is an effective vector of over 111 viruses from several families,particularly geminiviruses.Bemisia tabaci is regularly intercepted on plants coming into the UK where it is subjected to a policy of eradication.The UK maintains Protective Zone status against this pest.A main pathway of entry of B.tabaci into the Protected Zone involves propagating material,especially Poinsettia(Euphorbia pulcherrima).With increased insecticide resistance continuously being recorded,B.tabaci is becoming more difficult to control/eradicate.Recent research involving both entomopathogenic nematodes and fungi is showing much potential for the development of control programs for this pest.Both the nematode Steinernema feltiae and the fungus Lecanicillium muscarium have been shown to be most effective against second instar B.tabaci.Fine-tuning of the environmental conditions required has also increased their efficacy.The entomopathogens have also shown a high level of compatibility with chemical insecticides,all increasing their potential to be incorporated into control strategies against B.tabaci.

  11. Biotype Characterization, Developmental Profiling, Insecticide Response and Binding Property of Bemisia tabaci Chemosensory Proteins: Role of CSP in Insect Defense.

    Directory of Open Access Journals (Sweden)

    Guoxia Liu

    Full Text Available Chemosensory proteins (CSPs are believed to play a key role in the chemosensory process in insects. Sequencing genomic DNA and RNA encoding CSP1, CSP2 and CSP3 in the sweet potato whitefly Bemisia tabaci showed strong variation between B and Q biotypes. Analyzing CSP-RNA levels showed not only biotype, but also age and developmental stage-specific expression. Interestingly, applying neonicotinoid thiamethoxam insecticide using twenty-five different dose/time treatments in B and Q young adults showed that Bemisia CSP1, CSP2 and CSP3 were also differentially regulated over insecticide exposure. In our study one of the adult-specific gene (CSP1 was shown to be significantly up-regulated by the insecticide in Q, the most highly resistant form of B. tabaci. Correlatively, competitive binding assays using tryptophan fluorescence spectroscopy and molecular docking demonstrated that CSP1 protein preferentially bound to linoleic acid, while CSP2 and CSP3 proteins rather associated to another completely different type of chemical, i.e. α-pentyl-cinnamaldehyde (jasminaldehyde. This might indicate that some CSPs in whiteflies are crucial to facilitate the transport of fatty acids thus regulating some metabolic pathways of the insect immune response, while some others are tuned to much more volatile chemicals known not only for their pleasant odor scent, but also for their potent toxic insecticide activity.

  12. Crecimientoy metabolismo: la regulación y la vía de la insulina desde la mosca de la fruta, Drosophila melanogaster

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    Deyannira Otero-Moreno

    2016-01-01

    Full Text Available Drosophila melanogaster, la mosca de la fruta, es un organismo genético modelo que en años recientes se ha usado exitosamente para estudiar el control del metabolismo y el crecimiento. A pesar de poseer algunas diferencias con las vías de señalización homólogas a las de los vertebrados, las semejanzas son profundas y claras. En D. melanogaster, la vía de la insulina, homóloga a la de los vertebrados, regula tanto el metabolismo como el crecimiento del organismo a través de un receptor membranal único. A su vez, esta vía –que conjunta lo que en vertebrados es la vía de la insulina y la de los péptidos parecidos a la insulina- está regulada por la ingesta de nutrientes (carbohidratos y proteínas y por el control hormonal (hormona del crecimiento, ecdisona, upd2, hormona adipocinética, Ilp8. En consecuencia, normalmente se obtiene un crecimiento adaptable a las condiciones nutricionales que influye, como en los vertebrados, en el promedio de vida y en la capacidad reproductiva con un tamaño típico y una diferenciación armónica, a tono con el bauplandel organismo. Por el contrario las mutaciones y desviaciones dan por resultado partes desproporcionadas, menor capacidad reproductiva, y disminución tanto del tamaño como de la proliferación, y hasta la muerte.

  13. Dietas artificiais para a criação de larvas e adultos da mosca-das-frutas sul-americana

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    Adrise Medeiros Nunes

    2013-10-01

    Full Text Available O objetivo deste trabalho foi adequar as dietas artificiais para o desenvolvimento dos estágios de larva e adulto da mosca-das-frutas sul-americana (Anastrepha fraterculus. Para o estágio larval, foram testadas as seguintes dietas: D1, original, com 10 g de ágar; D2, modificada, com 3,6 g de ágar; e, D3, modificada, com bagaço seco de cana-de-açúcar. Para os adultos, foram testadas quatro dietas: A, levedura de cerveja + mel (2:1; B, açúcar refinado + extrato de levedura + gérmen de trigo cru (3:1:1; C, extrato de soja + açúcar mascavo + gérmen de trigo cru (3:1:1; e D, levedura seca de cervejaria + mel (2:1. Avaliaram-se os parâmetros biológicos de duração do período ovo-pupa, duração e viabilidade do estágio de pupa, massa média de pupas, razão sexual e duração e viabilidade do período ovo-adulto. O desenvolvimento larval em D1 e D2 foi semelhante e indicou que a criação de larvas pode ser realizada com 1/3 da quantidade de ágar da utilizada em D1. A utilização do bagaço seco de cana-de-açúcar, na dieta artificial, afetou negativamente o desenvolvimento larval. As dietas artificiais com levedura de cerveja + mel e com açúcar refinado + extrato de levedura + gérmen de trigo cru são as mais adequadas para a criação de adultos.

  14. Estudios de laboratorio para el control de Ceratitis capitata (Wiedmann (Diptera: Tephritidae (Mosca del Mediterráneo con Beauveria bassiana

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    Luis Porras

    2008-01-01

    Full Text Available Con el objetivo de seleccionar cepas promisorias de Beauveria bassiana para el control de Ceratitis capitata, se realizó, en condiciones de laboratorio, una serie de ensayos empleando la mosca adulta como estado vulnerable al parasitismo por el hongo entomopatógeno. Para la selección se utilizó una concentración de 5x109 CV.m-2 del hongo. Se determinó la CL90, la sobrevivencia media (SM, la compatibilidad con insecticidas, además de ensayos de producción con el hongo. Así como la compatibilidad de los insecticidas Mercaptotion 100% CE (Lupara® y Dimetoato 40% CE (Sistémico Icona con las cepas seleccionadas. Se cuantificó la viabilidad de los conidios en platos de Petri pos-tratamiento, a 50, 100 y 200% de la dosis comercial del insecticida. A partir de 7 cepas evaluadas (mortalidad 97-14% fueron seleccionadas la Bb 26, la Bb 259, la Bb 132, y la Bb 238. Los valores de CL90 estuvieron entre 1x109 y 3,8 x1011 CV.m-2 (Bb 238 y Bb 26, respectivamente. La SM de las cepas varió de 7-12 días (Bb 238 y Bb 26, respectivamente. La mayor producción fue de 7x109 UFC.mg-1 y 20,7 g.conidios.kg-1 de arroz (Bb 26. Todas las cepas fueron compatibles con Mercaptotion y la Bb 132 presentó la mayor compatibilidad con el Dimetoato. En conclusión, los ensayos en el laboratorio permitieron seleccionar cepas de B. bassiana con potencial para controlar C. capitata

  15. 烟粉虱暴发成因及其治理技术研究%Outbreak Reason of Cotton Whitefly [Bemisia Tabaci(Gennadius)]and its Integrated Pest Measure

    Institute of Scientific and Technical Information of China (English)

    慕卫; 刘峰; 刘海涛

    2003-01-01

    The reason of cotton whitefly [ Bemisia tabaci ( Gennadius) ] happened heavily in China in recent years was analyzed from its biology characteristic, host range, crop culture and environment situation, control measure. At last, integrated pest measure for control cotton whiteflywas clarified.

  16. Presence of the yeast Candida tropicalis in figs infected by the fruit fly Zaprionus indianus (dip.: Drosophilidae Presença da levedura Candida tropicalis em figos infestados pela mosca da fruta Zaprionus indianus (dip.: Drosophilidae

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    Luiz H. Gomes

    2003-04-01

    Full Text Available In the last years, the fruit fly Zapronius indianus became the most important plague of Brazilian fig production. A fermentation process is associated with infection of the fruit by this fly. A single yeast species, Candida tropicalis, was identified in all the infected figs. The presence of one species and the low genetic variability (RAPD of the isolates indicates an uncommonly strict interaction between C. tropicalis and Z. indianus.Nos últimos anos, a mosca-africana-do-figo Zaprionus indianus tem se tornado a praga mais importante desta cultura no Brasil. Um processo fermentativo está associado com a infecção dos frutos por esta mosca. Uma única espécie de levedura, Candida tropicalis, foi identificada nos figos infectados. A presença de uma única espécie de levedura e a baixa variabilidade genética (RAPD dos isolados indica uma relação muito estreita entre C. tropicalis e Z. indianus.

  17. Eficiência de substâncias atrativas na captura de moscas-das-frutas (diptera: tephritidae em goiabeiras no município de Itapecuru-Mirim (MA

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    Lemos Raimunda Nonata Santos

    2002-01-01

    Full Text Available O experimento foi conduzido em pomar comercial de goiaba (Psidium guajava L. cultivar 'Pêra Vermelha', localizado no município de Itapecuru-Mirim (MA, na Comunidade Magnificat, visando a adotar um sistema de manejo integrado de moscas-das-frutas através do monitoramento com armadilhas do tipo frasco caça-moscas (modelo garrafa plástica e atraentes de alimentação. O delineamento estatístico adotado foi o de blocos inteiramente casualizados, com cinco tratamentos e quatro repetições, sendo: suco de laranja (50%, acerola (30%, goiaba (30%, maracujá (30% e solução de açúcar cristal a 10 %. Verificou-se que o suco de maracujá (30% e a solução de açúcar cristal (10% foram mais atrativos para os adultos de Anastrepha distincta Greene, A. sororcula Zucchi, A. striata Schiner, A. obliqua Macquart e A. serpentina Wiedemann.

  18. Species of fruit flies (Tephritidae obtained of McPhail trap in the Bahia State, Brazil/ Espécies de moscas-das-frutas (Tephritidae obtidas em armadilhas McPhail no Estado da Bahia, Brasil

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    Miguel Francisco de Souza Filho

    2006-07-01

    Full Text Available The objective of this study was to provide knowledge on the species of fruit flies in commercial orchards in counties of the southern and extreme southern regions of the State of Bahia, Brazil. Flies were captured weekly by McPhail traps, using a hydrolyzed corn protein at 5%, as attractant. A total of 257 female was collected, and the species were identified as: Anastrepha fraterculus (77.4%, A. sororcula (4.7%, A. obliqua (2.7%, A. zenildae (0.8%, A. distincta (0.4%, A. consobrina (0.4%, Anastrepha sp.1 (5.1% and Ceratitis capitata (8.5%.O objetivo deste trabalho foi conhecer as espécies de moscas-das-frutas que ocorrem em pomares comerciais em alguns municípios da região sul e extremo-sul do estado da Bahia, Brasil. As moscas-dasfrutas foram capturadas, semanalmente, utilizando-se armadilhas McPhail, tendo como atrativo proteína hidrolisada de milho a 5%. Foi obtido um total de 257 espécimes fêmeas, pertencentes às espécies: Anastrepha fraterculus (77,4%, A. sororcula (4,7%, A. obliqua (2,7%, A. zenildae (0,8%, A. distincta (0,4%, A. consobrina (0,4%, Anastrepha sp.1 (5,1% e Ceratitis capitata (8,5%.

  19. Instabilidade da expressão de descritores morfológicos e fenológicos à variação ambiental em aveia-branca

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    Jossana Santos

    2017-05-01

    Full Text Available Caracteres morfológicos e fenológicos são utilizados na seleção, cruzamentos e descrição de genótipos, sua instabilidade frente a alterações ambientais pode determinar o seu valor na etapa de proteção de cultivares. Este trabalho foi desenvolvido com o objetivo de verificar a expressão de descritores morfológicos e fenológicos e, consequentemente, a dissimilaridade entre cultivares de aveia-branca (Avena sativa L. em dois períodos de cultivo. Para isso, cinco cultivares, protegidas e oriundas de quatro obtentores e, aqui, codificadas (G1, G2, G3, G4 e G5, foram semeadas dentro do período recomendado para a cultura no sul do do Brasil (outono-hibernal e fora desse período (hiberno-primaveril, com intervalo de quarenta dias. O experimento foi estabelecido em campo, em blocos casualizados, com três repetições. As cultivares foram avaliadas quanto a 42 descritores (15 quantitativos e 27 qualitativos. Os dados quantitativos foram submetidos à análise de variância, seguida da comparação de médias, e à análise multivariada, por meio da geração da distância euclidiana média. Os dados qualitativos foram submetidos à determinação da moda, seguida da obtenção do índice de similaridade. A relação entre as cultivares foi ilustrada por meio de dendrogramas. Foi calculado o índice de estabilidade dos descritores. A interação genótipo x ambiente foi observada em 28 descritores. A estabilidade de expressão, à alteração no período de cultivo, foi maior nos descritores qualitativos (44%, quando comparada aos quantitativos (7%. Os descritores qualitativos mais estáveis foram: cor do lema, pilosidade do nó superior, posição da folha-bandeira, pilosidade da base do grão, comprimento dos pelos basais do grão e comprimento da ráquila. O descritor quantitativo mais estável foi o comprimento da folha-bandeira. O atraso no período de cultivo da aveia-branca, de outono-hibernal para hiberno-primaveril, reduz o

  20. Capacidade combinatória para resistência àmancha branca em linhagens endogâmicas de milho

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    Paula de Souza Guimarães

    2009-12-01

    Full Text Available Estimaram-se as capacidades geral (CGC e específica (CEC de combinação para resistência à mancha branca de 24 linhagens do programa de melhoramento de milho do IAC, de diferentes procedências, sob esquemas de dois dialelos parciais (Dialelo A e B, em Mococa, na região nordeste do Estado de São Paulo, na safra 2004/2005. O delineamento experimental utilizado foi o de blocos ao acaso com 3 repetições e 2 testemunhas comerciais (IAC 8333 e DKB 350. Avaliou-se a severidade da mancha branca nas linhagens, nos 36 híbridos simples resultantes de cada dialelo parcial 6x6 e nos dois híbridos comerciais. A avaliação da doença foi realizada nos estádios de grãos leitosos a pastosos, através de escala de notas de 1 a 9, correspondendo a 0; 1; 2,5; 5; 10; 25; 50; 75 e mais de 75% de área foliar afetada. Houve diferenças significativas (PEstimates of the general combining abilities (GCA and specific combining abilities (SCA of resistance to white leaf spot were obtained in 24 different IAC maize lines, following two partial diallel schemes (Dialelo A and Dialelo B, evaluated in Mococa, north-east region of the São Paulo State, in 2004/2005. The trials followed a randomized blocks design with three replicates and two commercial checks (IAC 8333 and DKB 350. The severity of white leaf spot were evaluated in the lines, in the 36 single cross hybrids results of two partial diallel 6x6 and in the two commercial hybrids. The disease was assessed according to a scale of notes from 1 to 9, corresponding to: 0; 1; 2,5; 5; 10; 25; 50; 75 and + 75% affected leaf area in the adult plant, respectively. There was significant difference (P<0.01 among the hybrids for resistance to white leaf spot, making possible discrimination of hybrids. The lines more resistance were PM518, IP4035 (Dialelo A and IP398 (Dialelo B, while the hybrids IAC8333, PM 518 x IP4035 and IP701 x IP4035 in the Dialelo A and L8 x IP398, VER266 x IP398 and L161 x IP398 in the

  1. Conservation of natural enemies in cotton: comparative selectivity of acetamiprid in the management of Bemisia tabaci.

    Science.gov (United States)

    Naranjo, Steven E; Akey, David H

    2005-06-01

    The integrated control concept emphasizes the importance of both chemical and biological control for pest suppression in agricultural systems. A two-year field study was conducted to evaluate the selectivity of acetamiprid for the control of Bemisia tabaci (Gennadius) in cotton compared with a proven selective regime based on the insect growth regulators (IGRs) pyriproxyfen and buprofezin. Acetamiprid was highly effective in controlling all stages of B tabaci compared with an untreated control, and generally produced lower pest densities than the IGR regime. Univariate analyses indicated that nine of 17 taxa of arthropod predators were significantly depressed with the use of acetamiprid compared with an untreated control, including common species such as Geocoris punctipes (Say), Orius tristicolor (White), Chrysoperla carnea Stephens sensu lato, Collops vittatus (Say), Hippodamia convergens Guérin-Méneville, and Drapetis nr divergens. Compared with results from independent, concurrent studies using mixtures of broad-spectrum insecticides at the same research site, acetamiprid depressed populations of fewer predator taxa; but, for eight predator taxa significantly affected by both regimes, the average population reduction was roughly equal. In contrast, only four taxa were significantly reduced in the IGR regime compared with the untreated control and three of these were omnivores that function primarily as plant pests. Principal response curves analyses (a time-dependent, multivariate ordination method) confirmed these patterns of population change for the entire predator community. Predator:prey ratios generally increased with the use of both IGRs and acetamiprid compared with an untreated control, but ratios were consistently higher with IGRs. Parasitism by aphelinid parasitoids was unaffected or depressed slightly in all insecticide regimes compared with the control. Because of its high efficacy, acetamiprid may play an important role in later stages of B

  2. Repellent effect of alphacypermethrin-treated netting against Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Martin, T; Kamal, A; Gogo, E; Saidi, M; Delétré, E; Bonafos, R; Simon, S; Ngouajio, M

    2014-04-01

    For > 20 yr, Bemisia tabaci Gennadius persists as a begomovirus vector and is a serious problem in tomato production in many parts of the world. In tropical countries, the use of netting to protect horticultural crops has proven to be an effective and sustainable tool against Lepidoptera but not against small insects. This study evaluated the repellent effect of AgroNet 0.9T, a 0.9-mm pore diameter and 40-mesh size netting treated with alphacypermethrin insecticide against B. tabaci. This pyrethroid insecticide is known to have toxic and repellent effects against mosquitoes and has been used for treatment of mosquito nets. Two nontreated netting materials were used as control: AgroNet 0.9NT with 0.9-mm pore diameter and 40-mesh size and AgroNet 0.4NT with 0.4-mm pore diameter and 80-mesh size. The behavior of B. tabaci and its parasitoid Encarsia formosa Gahan as they progressed through the treated netting was studied in the laboratory in choice and no-choice tests. The development of wild B. tabaci population on tomato plants protected by the same nets was followed in two field trials implemented in Njoro, Kenya. Results obtained with the no-choice tests showed a significant reduction of movement on the treated net with 40-mesh (19%) compared with nontreated netting (35 and 46% with 80- and 40-mesh, respectively). The mortality of B. tabaci was significantly higher (two-fold) in the test tube containing only the treated netting compared with the nontreated one. The repellent effect of the treated netting was also demonstrated against E. formosa, but it did not have this toxic effect. Unlike for B. tabaci, the treated and nontreated nets appeared to have a similar repellent effect on E. formosa in the choice test, which suggests a learning behavior of the parasitoid. In both field tests, B. tabaci population was significantly lower on tomato protected by the treated net compared with the same nontreated net. However there was no significant difference in B. tabaci

  3. Distribution of Bemisia tabaci (Hemiptera: Aleyrodidae) biotypes in North America after the Q invasion.

    Science.gov (United States)

    McKenzie, Cindy L; Bethke, James A; Byrne, Frank J; Chamberlin, Joseph R; Dennehy, Timothy J; Dickey, Aaron M; Gilrein, Dan; Hall, Paula M; Ludwig, Scott; Oetting, Ronald D; Osborne, Lance S; Schmale, Lin; Shatters, Robert G

    2012-06-01

    After the 2004 discovery of the Bemisia tabaci (Gennadius) (Hemiptera Aleyrodidae) Q biotype in the United States, there was a vital need to determine the geographical and host distribution as well as its interaction with the resident B biotype because of its innate ability to rapidly develop high-level insecticide resistance that persists in the absence of exposure. As part of a coordinated country-wide effort, an extensive survey of B. tabaci biotypes was conducted in North America, with the cooperation of growers, industry, local, state, and federal agencies, to monitor the introduction and distribution of the Q biotype. The biotype status of submitted B. tabaci samples was determined either by polymerase chain reaction amplification and sequencing of a mitochondrial cytochrome oxidase I small subunit gene fragment and characterization of two biotype discriminating nuclear microsatellite markers or esterase zymogram analysis. Two hundred and eighty collections were sampled from the United States, Bermuda, Canada, and Mexico during January 2005 through December 2011. Host plants were split between ornamental plant and culinary herb (67%) and vegetable and field crop (33%) commodities. The New World biotype was detected on field-grown tomatoes (Solanum lycopersicum L.) in Mexico (two) and in commercial greenhouses in Texas (three) and represented 100% of these five collections. To our knowledge, the latter identification represents the first report of the New World biotype in the United States since its rapid displacement in the late 1980s after the introduction of biotype B. Seventy-one percent of all collections contained at least one biotype B individual, and 53% of all collections contained only biotype B whiteflies. Biotype Q was detected in 23 states in the United States, Canada (British Columbia and Ontario territories), Bermuda, and Mexico. Forty-five percent of all collections were found to contain biotype Q in samples from ornamentals, herbs and a single

  4. Pengelolaan Kutu Kebul (Bemisia tabaci Gen. dengan Sistem Barier pada Tanaman Tembakau

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    Tri Maruto Aji

    2015-07-01

    Full Text Available Since 2009, the leaf curl disease was observed on tobacco plants grown under net shadow of PTPN X (Persero and has caused yield losses up to 70%. The disease was likely to be associated with the existence of a high population of the sweet potato whitefly (Bemisia tabaci Gen. and the symptoms resembled that reported for Begomovirus infection on eggplant and tomatoes. This study aimed to know the effectiveness of physical barriers in combination with a biological barrier to avoid B. tabaci in infesting the farm. The research was done by monitoring tobacco diseases to measure the diseases intensity. Research for the management of insect vectorsB. tabaci were done based on two pretexts: (1 physical barrier using the type of net; and (2 combinations of a net with a plant (corn belt. The result showed that an effective control was obtained using a net with higher mesh size rather than using a standard net with low mesh size which was presently used by PTPN X (Persero. Corn barrier did not effective to control B. tabaci except as a wind breaker. INTISARI Peningkatan populasi kutu kebul (B. tabaci Gen. di daerah Klaten, Jawa Tengah pada tahun 2009 ternyata menjadi penyebab mewabahnya penyakit kerupuk pada tanaman Solanaceae di wilayah tersebut. Tanaman tembakau cerutu Vorstenlanden milik PTPN X (Persero yang ditanam di area bawah naungan (TBN yang berada di wilayah tersebut turut terjangkit wabah penyakit kerupuk setelah sebelumnya terindikasi terjadi peningkatan jumlah kutu kebul. Wabah penyakit kerupuk pada tembakau cerutu Vorstenlanden milik PTPN X (Persero telah menurunkan hasil hingga 70%. Gejala penyakit pada tembakau berupa penyakit kerupuk. Penelitian ini bertujuan untuk mengetahui efektivitas penerapan barier fisik sebagai langkah awal untuk mengendalikan populasi kutu kebul pada pertanaman tembakau cerutu milik PTPN X (Persero. Penelitian dimulai dengan memonitoring populasi kutu kebul dan peningkatan intensitas penyakit kerupuk pada tanaman

  5. Genetic variability of the whitefly Bemisia tabaci and its secondary endosymbionts in the Arabian Peninsula

    KAUST Repository

    Ragab, Alaa I.

    2013-05-01

    The whitefly Bemisia tabaci species complex has been well documented as one of the most economically important emergent plant virus vectors, through serious feeding damage to its broad range of plant hosts and transmission of plant viruses to important agricultural crops. It has been shown to have associations with endosymbionts which have significant effects on the insect fitness. The purpose of this study was to provide information for the biotype and secondary endosymbiont distribution for B. tabaci populations in the relatively unstudied Arabian peninsula. The geographical localization and variation in endosymbiont populations across the region were identified using a sequence-driven analysis of the population genetics of the secondary endosymbiont. Live field specimens were collected from 22 different locations in the region and preserved in 70% ethanol for genetic studies. Previously established procedures were used to extract and purify total insect DNA from 24-30 individual whiteflies for each location (Frohlich et al., 1999; Chiel et al., 2007). Specimens were subjected to PCR amplification using the respective 16S rDNAprimers for the Rickettsia, Hamiltonella, and Wolbachia to amplify endosymbiont DNA. PCR was run with primers for the highly conserved whitefly mitochondrial cytochrome oxidase subunit I (COI) gene for biotyping. Samples were sequenced using the Sanger method and the data analyzed to correlate the presence, prevalence and geographical distribution of endosymbionts in B. tabaci. Phylogenies 5 were constructed to track evolutionary differences amongst the endosymbionts and insects and how they have influenced the evolution of the regional populations. Samples were characterized by differences in the genomes and endosymbionts of common whitefly ‘biotypes’ that have different host plant preferences, vector capacities and insecticide resistance characteristics. It was found that the B biotype is the predominant haplotype, with no evidence of

  6. Cadeias de suprimentos de montadoras dos setores automobilístico e de linha branca: Uma análise comparativa por meio de estudos de caso

    Directory of Open Access Journals (Sweden)

    Aline Lamon Cerra

    2014-09-01

    Full Text Available O objetivo deste artigo é identificar e comparar características estruturais e relacionais de cadeias de suprimentos produtoras de motores para automóveis e de cadeias do setor de linha branca instaladas no Brasil. Foram realizados para isso três estudos de caso em cada um destes setores. Os processos de reestruturação dos dois setores desde meados da década de 1990 apresentaram traços semelhantes, e as montadoras estudadas aumentaram suas bases de fornecimento em função da ampliação da diversidade de modelos e produtos produzidos. Mas há diferenças entre os dois setores no que tange à sazonalidade de demanda, ao comprimento (quantidade de elos das cadeias e às relações das montadoras com fornecedores de segundo nível (da segunda camada de fornecimento. Os resultados mostram que, em cada setor, mesmo quando possuem objetivos estratégicos e prioridades competitivas de produção em alguma medida similares, as empresas adotam práticas e configurações de Gestão da Cadeia de Suprimentos (GCS distintas. Em cada um dos setores, há diferenças estruturais e relacionais importantes entre as cadeias de suprimentos. As montadoras estudadas apresentam diferentes níveis de terceirização de componentes, têm suas plantas posicionadas a distâncias distintas dos respectivos conjuntos de fornecedores e possuem diferentes políticas de suprimentos e números de fornecedores.

  7. Implication of the bacterial endosymbiont Rickettsia spp. in interactions of the whitefly Bemisia tabaci with tomato yellow leaf curl virus.

    Science.gov (United States)

    Kliot, Adi; Cilia, Michelle; Czosnek, Henryk; Ghanim, Murad

    2014-05-01

    Numerous animal and plant viruses are transmitted by arthropod vectors in a persistent, circulative manner. Tomato yellow leaf curl virus (TYLCV) is transmitted by the sweet potato whitefly Bemisia tabaci. We report here that infection with Rickettsia spp., a facultative endosymbiont of whiteflies, altered TYLCV-B. tabaci interactions. A B. tabaci strain infected with Rickettsia acquired more TYLCV from infected plants, retained the virus longer, and exhibited nearly double the transmission efficiency compared to an uninfected B. tabaci strain with the same genetic background. Temporal and spatial antagonistic relationships were discovered between Rickettsia and TYLCV within the whitefly. In different time course experiments, the levels of virus and Rickettsia within the insect were inversely correlated. Fluorescence in situ hybridization analysis of Rickettsia-infected midguts provided evidence for niche exclusion between Rickettsia and TYLCV. In particular, high levels of the bacterium in the midgut resulted in higher virus concentrations in the filter chamber, a favored site for virus translocation along the transmission pathway, whereas low levels of Rickettsia in the midgut resulted in an even distribution of the virus. Taken together, these results indicate that Rickettsia, by infecting the midgut, increases TYLCV transmission efficacy, adding further insights into the complex association between persistent plant viruses, their insect vectors, and microorganism tenants that reside within these insects. Interest in bacterial endosymbionts in arthropods and many aspects of their host biology in agricultural and human health systems has been increasing. A recent and relevant studied example is the influence of Wolbachia on dengue virus transmission by mosquitoes. In parallel with our recently studied whitefly-Rickettsia-TYLCV system, other studies have shown that dengue virus levels in the mosquito vector are inversely correlated with bacterial load. Our work

  8. Are Yellow Sticky Traps an Effective Method for Control of Sweetpotato Whitefly, Bemisia tabaci, in the Greenhouse or Field?

    Science.gov (United States)

    Lu, Yaobin; Bei, Yawei; Zhang, Jinming

    2012-01-01

    Yellow sticky traps are a common method for monitoring many pests, but it has not been shown whether they could be used as a control method. In this study the impact of yellow sticky traps on the population dynamics of the sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) was determined in the greenhouse and field. In the greenhouse, yellow sticky traps significantly suppressed the population increase of adult and immature whiteflies. The whitefly densities in the greenhouse with traps were significantly lower than the greenhouse without traps. In the field, traps did not have a significant impact on the population dynamics of adult and immature whiteflies. The densities in fields with traps were very similar to fields without traps. These results suggest that yellow sticky traps can be used as an effective method for the control of whiteflies in the greenhouse, but not in the field. This information will prove useful for the effective management of whiteflies in greenhouses. PMID:23445077

  9. Role of the Insect Supervectors Bemisia tabaci and Frankliniella occidentalis in the Emergence and Global Spread of Plant Viruses.

    Science.gov (United States)

    Gilbertson, Robert L; Batuman, Ozgur; Webster, Craig G; Adkins, Scott

    2015-11-01

    Emergence of insect-transmitted plant viruses over the past 10-20 years has been disproportionately driven by two so-called supervectors: the whitefly, Bemisia tabaci, and the Western flower thrips, Frankliniella occidentalis. High rates of reproduction and dispersal, extreme polyphagy, and development of insecticide resistance, together with human activities, have made these insects global pests. These supervectors transmit a diversity of plant viruses by different mechanisms and mediate virus emergence through local evolution, host shifts, mixed infections, and global spread. Associated virus evolution involves reassortment, recombination, and component capture. Emergence of B. tabaci-transmitted geminiviruses (begomoviruses), ipomoviruses, and torradoviruses has led to global disease outbreaks as well as multiple paradigm shifts. Similarly, F. occidentalis has mediated tospovirus host shifts and global dissemination and the emergence of pollen-transmitted ilarviruses. The plant virus-supervector interaction offers exciting opportunities for basic research and global implementation of generalized disease management strategies to reduce economic and environmental impacts.

  10. Aqueous extracts of some medicinal plants are as toxic as Imidacloprid to the sweet potato whitefly, Bemisia tabaci.

    Science.gov (United States)

    Ateyyat, Mazen A; Al-Mazra'awi, Mohammad; Abu-Rjai, Talal; Shatnawi, Mohamad A

    2009-01-01

    Aqueous extracts of nine plants, known to have medicinal activity, were tested for their toxicity against the sweet potato whitefly, Bemisia tabaci Genn. (Homoptera: Aleurodidae) compared to the toxicity of the insecticide, Imidacloprid. Extracts of Lepidiuim sativum L. (Brassicales: Brassicaceae) killed 71 % of early stage nymphs, which was not significantly different from mortality caused by Imidacloprid. Treatment of pupae with three plant extracts, L. sativum, Achillea biebersteinii L. (Asterales: Asteraceae), or Retama raetam (Forssk.) Webb and Berthel (Fabales: Fabaceae) prevented adult development, and treatment with R. raetam extract killed adults, at levels that were not significantly different from Imidacloprid. None of the other plants showed significant toxicity. However extracts of four plants, Pimpinella anisum L. (Apiales: Apiaceae), Galium longifolium (Sibth. and SM.) (Gentianales: Rubiaceae), R. raetam and Ballota undulata Bentham (Lamiales: Lamiaceae) had a repellent effect.

  11. Study of The Use Of Maize as Barrier Crop in Chili to Control Bemisia tabaci (Gennadius Population

    Directory of Open Access Journals (Sweden)

    Yogi Puspo Friarini

    2016-12-01

    Full Text Available This study was conducted to determine the effect of maize as barrier crop to prevent the spread of Bemisia tabaci (Gennadius, the yellow virus vector in pepper farming. The research was conducted in the field at Pakem, Sleman, during two cropping seasons from October 2014 to February 2015 as first planting period and in April to August 2015 as second planting period. The escalation of B. tabaci (Gennadius populations was directly correlated with virus yellow peppers increment. The result indicated that planting barrier was effective in reducing the spread of B. tabaci (Gennadius in pepper plants. The population of B. tabaci (Gennadius in plots with pepper surrounded by maize was lower compared to plots without maize barrier, showed that the yellow virus spreads on pepper can be minimized, and hence the incidence of yellow disease was also decreased.   INTISARI   Penelitian ini dilakukan untuk mengetahui pengaruh penanaman jagung sebagai pemberian tanaman pembatas (barrier untuk mengatasi penyebaran Bemisia tabaci (Gennadius yang merupakan vektor virus kuning pada tanaman cabai. Penelitian dilakukan di lahan pertanaman cabai di Pakem, Sleman. Penelitian dilaksanakan selama dua musim tanam dari bulan Oktober 2014 sampai dengan bulan Februari 2015 pada periode tanam I dan bulan April 2015 sampai dengan bulan Agustus 2015 pada periode tanam II. Meningkatnya populasi B. tabaci (Gennadius berbanding lurus dengan meningkatnya virus kuning pada cabai. Hasil penelitian ini menunjukkan bahwa penanaman tanaman pembatas (barrier cukup efektif mengurangi penyebaran B. tabaci (Gennadius pada ke dalam petak tanaman cabai. Populasi B. tabaci (Gennadius pada petak tanaman cabai yang dikelilingi tanaman jagung lebih rendah jika dibanding dengan petak tanaman cabai yang tidak dikelililing tanaman jagung, sehingga secara tidak langsung penyebaran virus kuning pada cabai dapat diminimalisir.

  12. Preoperative Nd:YAG laser anterior capsulotomy in white intumescent cataracts: report of 11 cases Capsulotomia anterior pré-operatória com Nd:YAG laser em cataratas brancas intumescentes: relato de 11 casos

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    Roberto Pinto Coelho

    2009-02-01

    Full Text Available Creating a continuous curvilinear capsulorhexis in eyes with white intumescent cataracts is a challenge due to the high risk of extension of capsular tears to the lens periphery. Several approaches have been described to avoid this complication and preoperative Nd:YAG laser anterior capsulotomy has been little reported as an optional technique. Eleven patients with white intumescent cataracts were submitted to preoperative Nd:YAG laser anterior capsulotomy. All patients had some degree of cortex falling in anterior chamber after laser application. No patient developed later complications. Thus, preoperative Nd:YAG laser anterior capsulotomy represents a safe and easy option for white intumescent cataracts.A realização da capsulorrexis curvilínea contínua em olhos com catarata branca intumescente é ainda considerada um desafio pelo alto risco de extensão da capsulotomia para a periferia do cristalino. Apesar da descrição de diversas técnicas cirúrgicas voltadas para a prevenção de tal complicação, o uso de Nd:YAG laser no pré-operatório tem raros relatos na literatura internacional. Onze pacientes com cataratas brancas intumescentes foram submetidos a capsulotomia pré-operatória com Nd:YAG laser. Todos os pacientes apresentaram, após a aplicação do laser, a saída de córtex liquefeito para a câmara anterior. Nenhum paciente apresentou complicações cirúrgicas com o procedimento. Desta forma, a capsulotomia anterior com Nd:YAG laser representa uma opção técnica fácil e segura no manejo de cataratas brancas intumescentes.

  13. Nutritional value of black and white oat cultivars ensiled in two phenological stages Valor nutricional de cultivares de aveia preta e branca ensiladas em dois estádios fenológicos

    Directory of Open Access Journals (Sweden)

    Diego Bitencourt de David

    2010-07-01

    Full Text Available It was evaluated in this work, crop yield, fermentative quality and nutritional value of the silage of cultivars of white (Avena Sativa L. and black (Avena Strigosa Schreb oats cut at two development stages. It was used an experimental randomized block design in a 4 x 2 factorial scheme, consisting of four oat cultivars (two cultivars of black oats: Aveia Preta Comum and UTFP 971; and two cultivars of white oats: ER 91156- 1- 2- 1 and SI 98105- b, with four replicates. The cultivars were ensiled at flowering and dough grain stages. Oat cut at dough grain stage, especially genotypes from white oat, allows the obtainment of a more productive and qualitative silage. Cultivar, genotype, and maturation stage affect protein fractioning and oat silage carbohydrates.Avaliaram- se a produção das culturas, a qualidade fermentativa e o valor nutricional da silagem de cultivares de aveia- branca (Avena Sativa L. e aveia- preta (Avena Strigosa Schreb submetidas ao corte em dois estádios de maturação. O delineamento experimental foi de blocos ao acaso, num arranjo fatorial 4 x 2, composto por quatro cultivares de aveia (dois de aveia- preta: Comum e UTFP 971; e dois de aveia- branca: ER 91156- 121 e SI 98105- b, com quatro repetições. Os cultivares foram ensilados nos estádios de floração e grão pastoso. O corte da aveia no estádio de grão pastoso, sobretudo dos genótipos de aveia- branca, possibilita obter silagem de maior qualidade, tanto produtiva quanto qualitativa. O cultivar, o genótipo e o estádio de maturação influenciam o fracionamento das proteínas e dos carboidratos de silagens de aveia.

  14. Quando a tradução (re)conta a história: análise textual e tradução comentada de interrogatórios da \\'Rosa Branca\\'

    OpenAIRE

    Anna Carolina Schäfer

    2015-01-01

    O presente trabalho tem por objetivo produzir uma tradução comentada, do alemão para o português, de uma seleção de documentos emblemáticos da resistência alemã ao Nacional-Socialismo. O corpus constitui-se especificamente de registros escritos dos interrogatórios (em alemão: Verhörprotokolle, protocolos de interrogatório) conduzidos em fevereiro de 1943 pela Polícia Secreta Nazista com os irmãos Hans e Sophie Scholl. Ambos eram integrantes do grupo A Rosa Branca, formado sobretudo por estuda...

  15. Efeitos dos alcalóides de Geissospermum urceolatum a. H. Gentry (acariquara-branca) na pressão arterial e na contração do músculo liso de ratos

    OpenAIRE

    Martins, Suzana da Silva de Oliveira

    2010-01-01

    Geissospermum urceolatum é uma Apocynaceae conhecida popularmente como acariquara-branca, acariquara, quinarana, acariubarana, acarirana, pereira, pau-pereira e pau-forquilha. Além da qualidade de suas madeiras, a casca da espécie possui um gosto amargo sendo utilizada comumente na forma de infusões pela medicina popular da Região Amazônica para tratamento de dores no estômago, tontura, febre e malária. Esta espécie não conta com trabalhos científicos confirmando essas ações. Este trabalho mo...

  16. Levantamento de moscas-das-frutas e seus parasitoides em citros, no município de Viçosa, Minas Gerais Survey of fruit-flies and their parasitoids in citrus in Viçosa, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Daniel Lucas Magalhães Machado

    2012-12-01

    Full Text Available As moscas-das-frutas são responsáveis por grandes perdas em fruteiras comerciais no Brasil, por isso é fundamental conhecer as espécies predominantes na região. Objetivou-se com este trabalho estudar a ocorrência de moscas-das-frutas (Diptera: Tephritidae e seus parasitoides em laranjas doces (Citrus sinensis L. Osbeck, tangerina Poncã (Citrus reticulata Blanco e mexerica Rio (Citrus deliciosa Ten, no município de Viçosa, Minas Gerais. Os frutos foram coletados em abril de 2008. No laboratório eles foram acondicionados em caixas plásticas contendo areia umedecida e em ambiente controlado para obtenção dos pupários, que foram contados, acondicionados em frascos de vidro com areia fina e mantidos em estufa até a emergência dos adultos. Somente uma espécie de mosca-das-frutas (Anastrepha fraterculus (Wiedemann, 1830 e uma de parasitoide (Doryctobracon brasiliensis Szépligeti foram identificadas. Dentre as variedades, a laranja doce Baianinha apresentou o maior índice de infestação, e os menores foram atribuídos à mexerica Rio e à tangerina Poncã.Fruit flies are responsible for large losses in commercial orchards in Brazil, thus, it is important to know the predominant species in the region. The objective of this study was to study the occurrence of fruit flies (Diptera: Tephritoidae and of their parasitoids in sweet orange (Citrus sinensis L. Osbeck, 'Poncã' mandarin (Citrus reticulate Blanco and 'Rio' tangerine (Citrus deliciosa Ten, in Viçosa, Minas Gerais. The fruits were collected in April 2008. In the laboratory, the fruits were stored in plastic boxes containing moist sand in a controlled environment, to obtain pupae. Then, the pupae were counted, placed in glass bottles with fine sand and kept in an oven until adult emergence. Only one species of fruit fly (Anastrepha fraterculus (Wiedemann, 1830 and one species of parasitoid (Doryctobracon brasiliensis Szépligeti were identified. Among the varieties, the sweet

  17. RNA interference-mediated knockdown of the hydroxyacid-oxoacid transhydrogenase gene decreases thiamethoxam resistance in adults of the whitefly Bemisia tabaci

    OpenAIRE

    Xin Yang; Wen Xie; Ru-mei Li; Xiao-mao Zhou; Shao-li Wang; Qing-jun Wu; Ni-na Yang; Ji-xing Xia; Ze-zong Yang; Li-tao Guo; Ya-ting Liu; You-jun Zhang

    2017-01-01

    Bemisia tabaci has developed a high level of resistance to thiamethoxam, a second generation neonicotinoid insecticide that has been widely used to control this pest. In this study, we investigated whether hydroxyacid-oxoacid transhydrogenase (HOT) is involved in resistance to the neonicotinoid insecticide thiamethoxam in the whitefly. We cloned the full-length gene that encodes HOT in B. tabaci. Its cDNA contains a 1428-bp open reading frame encoding 475 amino acid residues. Then we evaluate...

  18. Insecticide resistance in Bemisia tabaci Gennadius (Homoptera : Aleyrodidae) and Anopheles gambiae Giles (Diptera : Culicidae) could compromise the sustainability of malaria vector control strategies in West Africa

    OpenAIRE

    2013-01-01

    Insecticides from the organophosphate (OP) and pyrethroid (PY) chemical families, have respectively, been in use for 50 and 30 years in West Africa, mainly against agricultural pests, but also against vectors of human disease. The selection pressure, with practically the same molecules year after year (mainly on cotton), has caused insecticide resistance in pest populations such as Bemisia tabaci, vector of harmful phytoviruses on vegetables. The evolution toward insecticide resistance in mal...

  19. 'Patrícia branca': mutação somática na videira cultivar Patrícia (IAC 871-41 'Patrícia branca': somatic mutation in 'Patrícia' (IAC 871-41

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    Maurilo Monteiro Terra

    1984-01-01

    Full Text Available 'Patrícia' grape of black, fleshy, round, 20° Brix and low acidity berries, has risen through hybridization between 'Soraya' (IAC 501-6 and selection IAC 544-14, made in October 1959 at the Instituto Agronômico, Campinas (IAC. Commercial vineyards of this cultivar were set since 1970 in Jundiaí, Itupeva and Atibaia regions of São Paulo State, expanding to North Paraná and São Francisco Valley in Northeastern Brazil. In 1980, in a commercial vineyard at Chácara Extra Vitis, Bairro do Poste, Jundiai, São Paulo State, Brazil, two bunches of white berries were observed in one plant twig of cultivar Patrícia. Such twig was marked and in the winter of the same year it was used for grafts. All grafts gave also bunches with white berries. In 1981 winter new grafts were made with twigs of these plants at Chácara Extra Vitis and at Estação Experimental de Jundiaí (IAC which confirmed the presence of white berries bunches. Such observation shows a somatic mutation of 'Patrícia' (IAC 871-41 which was named Patrícia Branca.

  20. Efeito da temperatura de secagem na qualidade de grãos de aveia branca Effect of drying temperature on the quality of white oat grains

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    Leandro da Conceição Oliveira

    2010-04-01

    Full Text Available Objetivou-se, com o trabalho, avaliar o efeito de diferentes temperaturas do ar de secagem na qualidade física, química e biológica de grãos de aveia branca da cultivar Albasul. Grãos de aveia (Avena sativa L. foram submetidos à secagem estacionária com temperaturas de 25, 50, 75 e 100 ºC até a umidade de 13 %, em delineamento inteiramente casualizado. Nas amostras, foram determinados peso volumétrico, peso de 1000 grãos, germinação e vigor. Os grãos de aveia foram submetidos ao descascamento, moagem em granulometria inferior a 0,5 mm e avaliadas quanto a composição centesimal, atividade residual das enzimas lipase e peroxidase, cor e teor de beta-glicanas. O aumento de temperatura do ar de secagem intensificou a redução da qualidade biológica, expressa por meio do poder germinativo e vigor, além de provocar reduções no peso de 1000 grãos e peso volumétrico. As condições de secagem não foram suficientes para inativar as enzimas lipase e peroxidase, embora tenham provocado reduções nas suas atividades. Na secagem realizada com temperatura do ar superior a 75 ºC ocorreu redução significativa no teor de beta-glicanas.The objective of this research was to investigate the effect of different air drying temperatures upon the physical, chemical and biological quality of white oat grains, Albasul cultivar. Oat grains (Avena sativa L. were submitted to stationary drying at 25, 50, 75 and 100 ºC until 13 % of moisture, in totally randomized arrangement. In the samples, volumetric weight, weight of 1000 grains, germination and vigor were determined. The oats grains were husked, grounded at granulometry inferior to 0.5 mm, and analyzed according to centesimal composition, residual activity lipase and peroxidase, color and content of â-glucans. Increasing the temperature of drying air intensified the reduction of biological quality, expressed through germinative power and vigor, and also led to a decrease in weight of 1000

  1. Efeito da mosca-dos-chifres, Haematobia irritans (L. (Diptera: Muscidae, no ganho de peso de bovinos Nelore Effects of the horn fly, Haematobia irritans (L. (Diptera: Muscidae in the weight gain on Nellore cattle

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    Ivo Bianchin

    2004-06-01

    Full Text Available A presente investigação foi realizada devido à escassez, no Brasil, de informações sobre os possíveis danos decorrentes da ação hematófaga da mosca-dos-chifres, Haematobia irritans (L., em bovinos da raça Nelore. O estudo foi realizado durante quatro estações chuvosas (outubro a abril, de 1991 a 1995. Em cada ano, 80 bovinos foram utilizados de acordo com os seguintes tratamentos: 28 touros com um ano de idade divididos em quatro grupos; 20 bois com idade de dois anos divididos em quatro grupos, e 32 bois com três anos e divididos em oito grupos. Metade dos grupos de animais de cada idade eram tratados contra H. irritans com intervalos de 28 dias e os demais mantidos como grupos controle. As moscas foram contadas a cada 14 dias e o peso dos bois registrado a cada 28. O número médio de mosca/animal dos grupos controle para o primeiro, segundo, terceiro e quarto anos do estudo foi, respectivamente: cinco, cinco, quatro e cinco, nos animais de um ano; 15, 11, 13 e 27, nos de dois anos e 55, 31, 40 e 51, nos de três anos. Observou-se que maior número de moscas (PThis investigation was carried out due the lack of information about the possible effects of the blood-feeding horn fly, Haematobia irritans (L., on Nellore cattle. Data were recorded during four rainy seasons (October to April from 1991 to 1995. In each year, 80 animals were utilized according to the following treatments: twenty-eight 1-year old bulls divided into four groups; twenty 2-year old cattle divided into four groups and thirty-two 3-year old cattle divided into eight groups. Treatments against H. irritans were conduced at about 28-day intervals on half part of each age groups and the remainders groups maintained without treatment as control. The flies were counted at 14-day intervals and the animals weight registered at each 28-day intervals. The values for the mean flies number on the animals of the control groups in the first, second, third and fourth years of

  2. Estrutura da comunidade de moscas-das-frutas (Diptera: Lonchaeidae e Tephritidae) e seus parasitoides (Hymenoptera) relacionados a espécies de plantas em uma policultura orgânica no município de Paraibuna - SP

    OpenAIRE

    2014-01-01

    As espécies de plantas disponíveis em uma comunidade, sua estrutura e abundância são elementos cruciais que influenciam nas dinâmicas e interações de populações de insetos herbívoros, uma vez que definem a base de recursos e refletem na interação com outras populações de insetos herbívoros, como predadores e parasitoides. Estudos relacionados às moscas-das-frutas concentram-se em levantamentos de espécies, em especial aquelas consideradas pragas, e abordam principalmente os padrões populacion...

  3. Infestação da mosca-negra-dos-citros (Aleurocanthus woglumi Ashby em pomares de citros, em sistemas de plantio convencional e agroflorestal Infestation of citrus blackfly in citrus (Aleurocanthus woglumi Ashby orchards conventional and agroforestry

    Directory of Open Access Journals (Sweden)

    Anderson Gonçalves Da Silva

    2011-03-01

    Full Text Available Objetivou-se com o presente trabalho avaliar a infestação da mosca-negra-dos-citros em pomares de citros, em sistemas de plantio convencional e agroflorestal. A área experimental está localizada no município de Capitão Poço-PA, onde foram realizadas 12 amostragens durante o período de setembro de 2008 a outubro de 2009, avaliando a presença ou a ausência da praga nas laranjeiras, em ambos os sistemas de produção. Pelos resultados obtidos, observou-se que o sistema de plantio agroflorestal apresentou maior incidência de plantas com presença de mosca-negra-dos-citros comparado ao convencional, houve influência da temperatura na regulação da população da praga, e precipitações elevadas reduziram o número de plantas com presença de A. woglumi.The purpose of this study was to evaluate the infestation of citrus blackfly the in a citrus orchard in conventional tillage systems and agroforestry. The experimental area is located in the municipality of Capitão Poço, PA, where 12 samples were taken during the period from September 2008 to October 2009, evaluating the presence or absence of the pest in both production systems. The results showed that the system of agroforestry plantation showed higher incidence of plants with presence of citrus blackfly compared to conventional, there was influence of temperature on the regulation of pest population and heavy rain reduced the number of plants with presence of A.woglumi.

  4. ESPÉCIES DE MOSCA-DAS-FRUTAS (DIPTERA: TEPHRITIDAE E SEUS PARASITÓIDES EM ITUMBIARA-GO SPECIES OF FRUIT FLIES (DIPTERA: TEPHRITIDAE AND THEIR PARASITOIDS IN ITUMBIARA-GO

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    Ândersen Terra de Oliveira

    2007-09-01

    Full Text Available

    A mosca-das-frutas apresenta ampla distribuição geográfica, sendo encontrada praticamente no mundo todo, causando prejuízos às espécies frutíferas de importância econômica. O objetivo deste trabalho foi conhecer a Tephritidae na região de Itumbiara e seus inimigos naturais. As pupas foram coletadas em frutas em estado de apodrecimento. Entre Tephritidae, Anastrepha fraterculus foi a espécie mais abundante. Entre os parasitóides, Doryctobracon areolatus foi a espécie mais comum.

    PALAVRAS-CHAVE: Insecta; Hymenoptera; Tephritidae; parasitóides; mosca-das-frutas.

    The fruit flies show a huge geographic distribution, being found practically all over the word, bringing damages to the fruit trees that have an economic importance. The objective of this work was to know the Tephritidae in Itumbiara region and their natural enemies. The pupaes were collected of fruits decaying. Among the Tephritidae, Anastrepha fraterculus was the most abundant specie. Among the parasitoids, Doryctobracon areolatus was the most common specie.

    KEY-WORDS: Insecta; Hymenoptera; Tephritidae; parasitoids; fruit flies.

  5. An outbreak of scalp white piedra in a Brazilian children day care Surto de piedra branca afetando os cabelos do couro cabeludo de crianças em creche brasileira

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    Ana Maria Roselino

    2008-10-01

    Full Text Available White piedra is a superficial mycosis caused by Trichosporon spp. that affects the hair shaft of any part of the body. It is presented an outbreak of scalp white piedra seen in 5.8% of the children frequenting a day care in Northeastern of São Paulo State, Brazil. Mycological exam and culture identified T. cutaneum in all five cases, and scanning electron microscopy of nodules around hair shaft infected by Trichosporon spp. is demonstrated comparing them with those of black piedra and with nits of Pediculous capitis.Piedra branca caracteriza-se por ser micose superficial, causada por Trichosporon spp., que compromete a haste dos pelos de qualquer região do corpo. Um surto de piedra branca, afetando os cabelos do couro cabeludo, foi registrado em 5,8% das crianças que freqüentavam uma creche na região nordeste do estado de São Paulo. Exame micológico direto e cultura identificaram T. cutaneum nas cinco crianças afetadas. Enfatiza-se a utilização da microscopia eletrônica de varredura, que mostrou nódulos circundando a haste dos cabelos infectada por Trichosporon spp., comparando-os com nódulos de Piedra nigra e com lêndeas de Pediculus capitis.

  6. Control Químico de la Mosca de los Establos, Stomoxys Calcitrans (L y Otros Insectos Asociados con Estipes de Palma Africana en Descomposición

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    Ureta Sandino Eduardo

    1972-12-01

    Full Text Available En ensayos para determinar el efecto del diazinon 1% I.A. (ingrediente activo; bromophos 1 % I.A.; dieldrin 0.5% I.A., 2% I.A. y methomyl 0.1 % I.A. sobre larvas de Stomoxys calcilrans y otros insectos asociados con tipes de palma africana (Elaeis guineensis en descomposición, se encontró que los tratamientos con diazinon 1% I.A. y bromophos 1% I.A. fueron los más efectivos para impedir la proliferación en éstos de las larvas de Slomoxys calcilralls. Ambos insecticidas protegieron eficientemente los estipes por lo menos durante dos semanas. El dieldrin al 0.5% I. A. y 2% I. A., aunque inferior al bromophos 1% I.A. y al diazinon 1% I.A. también fue efectivo para impedir la proliferación de larvas de la mosca en los troncos de palma africana en descomposición. El tratamiento con methomyl 0.1 % I. A. al parecer no impidió la multiplicación de las larvas en los estipes, según pudo observarse en muestras tomadas a las dos semanas de haber sido aplicado el producto. El diazinon 1% I.A: bromophos 1 % I.A.; dieldrin 0.5% I.A. y 2% I.A., aparentemente fueron eficaces para controlar los adultos de Limnobaris calandriformis y Metamasius hemipterus, los cuales eran atraídos en grandes cantidades a los trozos de tallo de palma recién rajada, así como también impidieron la proliferación en éstos de las larvas de los dípteros Ormidea obesa y Hermelia sp./Abstract Several tests were carried out to determine the effectiveness of diazinon 1% I.A., bromophos 1% I.A., dieldrin 0.5 and 2% I.A., and methomyl 0.1 % on larvae of the stable fly, Stomoxys calcitrans, and other insects associated with dead trunks of the oil palm (Elaeis guineesis.The results showed by the author indicate that diazinon and bromophos were the most effective materials tested. Both insecticides protected well the dead trunks for at least two weeks. Dieldrin (both doses although less efficient than diazinon, was also effective in preventing the development of great numbers of

  7. Avaliação da atividade antimicrobiana do extrato etanólico bruto da casca da sucupira branca (Pterodon emarginatus Vogel - Fabaceae Evaluation of antimicrobial activity of crude ethanol extract from the bark of "sucupira branca" (Pterodon emarginatus Vogel - Fabaceae

    Directory of Open Access Journals (Sweden)

    K.G.L. Bustamante

    2010-09-01

    Full Text Available Pterodon emarginatus Vogel (Fabaceae é uma árvore do Cerrado conhecida popularmente como "sucupira branca, faveiro, fava de sucupira e sucupira lisa" e utilizada na medicina popular em preparações anti-reumáticas, antiinflamatórias, analgésicas e antiinfecciosas. Esse trabalho teve por objetivo fazer a triagem fitoquímica do pó e avaliar a atividade antimicrobiana do extrato etanólico bruto das cascas da P. emarginatus contra bactérias Gram-positivas, Gram-negativas e o fungo Candida albicans. O extrato etanólico bruto foi obtido a partir das cascas dessecadas e pulverizadas. A concentração inibitória mínima (CIM do extrato bruto foi determinada utilizando-se o inoculador de Steers. Os testes fitoquímicos detectaram a presença de flavonóides, heterosídeos saponínicos, resinas e traços de esteróides e triterpenóides. As CIM do extrato etanólico foram de 0,18 mg mL-1 para as bactérias Gram-positivas Rhodococcus equi ATCC 25923, Micrococcus luteus ATCC 9341, Micrococcus roseus IPTSP/UFG e para as bactérias Gram-negativas Serratia marcescens ATCC 14756 e Pseudomonas aeruginosa ATCC 9027; de 0,37 mg mL-1 para a Enterobacter cloacae FT 505 LEMC/EPM/UFG e de 0,74 mg mL-1 para as demais bactérias testadas e para o fungo C. albicans. O presente estudo abre perspectivas para o uso da cascas da P. emarginatus como antimicrobiano.Pterodon emarginatus Vogel (Fabaceae is a Cerrado tree popularly known as "sucupira branca", "faveiro", "fava de sucupira" and "sucupira lisa" and has been used in folk medicine as antirheumatic, anti-inflammatory, analgesic and anti-infective. The aim of this work was to perform the phytochemical screening of the powder and to evaluate the antimicrobial activity of crude ethanol extract from P. emarginatus barks against Gram-positive bacteria, Gram-negative bacteria and the fungus Candida albicans. The crude ethanol extract was obtained from desiccated and pulverized barks. Its minimum inhibitory

  8. Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae adults: I. Gliricidia sepium (Fabaceae

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    Guillermo Flores

    2008-12-01

    Full Text Available Bemisia tabaci is an important virus vector on a number of crops worldwide. Therefore, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period. Thus, the crude extract and four fractions thereof (water, water:methanol, methanol, and diethyl ether of mother-of-cocoa (Gliricidia sepium, Fabaceae were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract and some fractions exerted such effect on the insect. In the former (in sleeve cages, three fractions caused deterrence at doses as low as 0.1% (methanol, 0.5% (water:methanol and 1.5% (diethyl ether. However, in the latter (plants exposed in a greenhouse no one of the fractions performed well, suggesting that the deterrent principles somehow decomposed under the experimental conditions. Rev. Biol. Trop. 56 (4: 2099-2113. Epub 2008 December 12.Mundialmente, Bemisia tabaci es un importante vector de virus en numerosos cultivos. Por tanto, un enfoque preventivo para enfrentar las epidemias virales podría ser el empleo de sustancias repelentes o fagodisuasivas en las etapas tempranas del desarrollo de las plantas (período crítico. Así, tanto el extracto crudo como cuatro fracciones (agua, agua:metanol, metanol y éter dietílico del madero negro (Gliricidia sepium, Fabaceae fueron evaluadas en cuanto a su actividad fagodisuasiva sobre los adultos de B. tabaci en condiciones de invernadero, utilizando plantas de tomate, en Turrialba, Costa Rica. Tanto los experimentos de escogencia restringida como los de escogencia irrestricta revelaron que el extracto crudo y algunas fracciones mostraron dicha actividad. En los primeros experimentos (en jaulas de manga, tres fracciones causaron fagodisuasión a dosis tan bajas como 0.1% (metanol, 0.5% (agua:metanol y

  9. Biological aspects of Bemisia tabaci (Genn.) B biotype (Hemiptera: Aleyrodidae) on six bean genotypes; Aspectos biologicos de Bemisia tabaci (Genn.) biotipo B (Hemiptera: Aleyrodidae) em seis genotipos de feijoeiro

    Energy Technology Data Exchange (ETDEWEB)

    Oriani, Maria A. de G. [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Ecologia e Biologia Evolutiva; Vendramin, Jose D. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. de Entomologia, Fitopatologia e Zoologia Agricola; Brunherotto, Rogerio [Fundacao Municipal de Ensino Superior de Braganca Paulista, SP (Brazil)

    2008-03-15

    The silverleaf whitefly is one of the most harmful pests that attack bean crops, mainly for extracting large quantities of phloem sap and transmitting the bean golden mosaic virus. Resistant germplasm plants can be an important method for controlling this pest. The biological aspects of Bemisia tabaci B biotype on bean (Phaseolus vulgaris) genotypes were evaluated. The tests were conducted under laboratory conditions, with the following genotypes: Arc 1, Arc 3s, Arc 5s, G13028, G11056 and Porrillo 70. The bean plants in a stage IV-1 were infested during one day with silverleaf white flies. Afterwards the eggs and nymphs were observed until adult emergence. Longevity and fecundity of emerged insects were also evaluated. The longest development time occurred for nymphs fed on Arc 3s genotype (26.5 days), following by G11056 (25.9 days) and G13028 (25.3 days). The development period was 5.5 days longer in Arc 3s when compared with Porrillo 70. Also, the wild genotypes Arc 3s and G11056 showed higher mortality rates (94.7% and 83.1%, respectively), which may suggest antibiosis and/or feeding non preference resistance type. For this reason, although longevity and fecundity were not influenced when the whitefly fed on resistant genotypes (Arc 3s, G11056, G13028 and Arc 5s), those genotypes can be used for bean breeding program towards B. tabaci B biotype. (author)

  10. Factors affecting oviposition of Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) in sweet pepper; Fatores que afetam a oviposicao de Bemisia tabaci (Genn.) biotipo B (Hemiptera: Aleyrodidae) em pimentao

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Larissa C. de; Campos, Alcebiades R. [UNESP, Ilha Solteira, SP (Brazil). Dept. de Fitossanidade, Engenharia Rural e Solos]. E-mail: lclima@aluno.feis.unesp.br; campos@bio.feis.unesp.br

    2008-03-15

    Bemisia tabaci (Gen.) biotype B is considered a pest of economical importance for several vegetables. The oviposition behaviour of the while fly was evaluated in sweet pepper plants. The trials were carried out under greenhouse condition and in the Laboratory of Entomology of DEFERS/ UNESP, Campus of Ilha Solteira-SP, with the sweet pepper Magali-R genotype. The effect of plant age on the whitefly oviposition was evaluated in free-choice tests, in plants, 25, 30, 35, 40 and 45- day-old, as egg distribution in the plant and on the leaf blade was evaluated in 35-days-old plants. In a no-choice tests, 35-day-old plants were used to evaluate the effect of the densities of 50, 100, 150, 200 and 250 adults per plant on the number of eggs laid by insects. The silver leaf whitefly preferred to oviposition the third to sixth leaflets, of the medium and superior part of plants of sweet pepper; the leaf blade areas, located in the lobes right and left close the base of the leaf were the preferential site for whitefly oviposition. Older plants, 40- and 45-day-old, were preferentially used for oviposition, and 200 and 250 adults per plant were both enough to lay a number of eggs that allowed to differentiate among sweet pepper genotypes with different whitefly resistance levels. (author)

  11. Enhancement of Phenylalanine Ammonia Lyase, Polyphenoloxidase, and Peroxidase in Cucumber Seedlings by Bemisia tabaci(Gennadius) (Hemiptera: Aleyrodidae) Infestation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study, the activities of phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO), and peroxidase (POD) were assayed in cucumber seedlings (Cucumis sativus L.) at 0, 6, 12, 24, 48, 72, and 96 h after they were infested by Bemisia tabaci (Gennadius) using spectrophotometric analysis. The results indicated that herbivore infestation increased the activities of PAL, PPO, and POD. The enzymes showed different activity levels at different times after the infestation. The PAL activity reached the first high peak by 23.1% at 6 h and the highest peak by 29.1% at 48 h compared to the control. The PPO activity reached the first high peak by 22.7% at 6 h and the highest peak by 52.6% at 24 h, and the POD activity reached the highest peak by 213.2% at 6 h and another higher peak value by 135.2% at 96 h. The results suggest that the enhanced activities of the enzymes may contribute to bioprotection of cucumber plants against B. Tabaci infestation.

  12. Resistance induction in chrysanthemum due to silicon application in the management of whitefly Bemisia tabaci Biotype B (Hemiptera: Aleyrodidae

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    Bruno Almeida Melo

    2015-12-01

    Full Text Available Whitefly Bemisia tabaci biotype B (Hemiptera: Aleyrodidae is a key pest in many cultures worldwide, among them chrysanthemum. The aim of this study was to evaluate whether silicon application in chrysanthemum plants can induce resistance to whitefly. The experiments were conducted in chrysanthemum cv. Rage in a greenhouse at EPAMIG in São João Del Rei, MG. The treatments were: 1 silicon applied as soil drench (dosage of 2t SiO2/ha on the 4th day after planting, 2 two silicon applied as foliar spray on the 4th and 12th days after planting, 3 control, with 10 replications each. The plants were infested with 100 whitefly adults/pot, released 16 days after planting. The number and viability of whitefly eggs and number of nymphs and adults were evaluated. The production of fresh and dry matter of shoots and the silicon content in plants were also evaluated. Silicon did not affect the whitefly oviposition preference; however, it affected the development of nymphs in free-choice test. Foliar silicon applications reduced the viability of whitefly eggs. There was no difference of fresh and dry weight and silicon content in plants with the application of silicon. Therefore, foliar silicon application on chrysanthemum can reduce the viability of eggs and delay the development of nymphs and thus contribute to the integrated whitefly management in commercial crops.

  13. Single basal application of thiacloprid for the integrated management of Meloidogyne incognita and Bemisia tabaci in tomato crops

    Science.gov (United States)

    Dong, Sa; Ren, Xiaofen; Zhang, Dianli; Ji, Xiaoxue; Wang, Kaiyun; Qiao, Kang

    2017-01-01

    Tomato growers commonly face heavy nematode (Meloidogyne incognita) and whitefly (B-biotype Bemisia tabaci) infestations, and previous studies demonstrated that thiacloprid could be used to control M. incognita and B. tabaci in cucumber. However, the efficacy of a single basal application of thiacloprid to control both pests and its effect on yield in tomato remains unknown. In this study, the potential of thiacloprid application to the soil for the integrated control of M. incognita and B. tabaci in tomato was evaluated in the laboratory and the field. Laboratory tests showed that thiacloprid was highly toxic to whitefly adults and eggs with an average lethal concentration 50 (LC50) of 14.7 and 62.2 mg ai L−1, respectively, and the LC50 of thiacloprid for nematode J2s and eggs averaged 36.2 and 70.4 mg ai L−1, respectively. In field trials, when thiacloprid was applied to the soil at 7.5, 15 and 30 kg ha−1 in two consecutive years, whitefly adults decreased by 37.8–75.4% within 60 days of treatment, and the root-galling index was reduced by 31.8–85.2%. Optimum tomato plant growth and maximum yields were observed in the 15 kg ha−1 treatment. The results indicated that a single basal application of thiacloprid could control M. incognita and B. tabaci and enhance tomato growth and yield. PMID:28120937

  14. Rapid genetic turnover in populations of the insect pest Bemisia tabaci Middle East: Asia Minor 1 in an agricultural landscape.

    Science.gov (United States)

    Dinsdale, A; Schellhorn, N A; De Barro, P; Buckley, Y M; Riginos, C

    2012-10-01

    Organisms differ greatly in dispersal ability, and landscapes differ in amenability to an organism's movement. Thus, landscape structure and heterogeneity can affect genetic composition of populations. While many agricultural pests are known for their ability to disperse rapidly, it is unclear how fast and over what spatial scale insect pests might respond to the temporally dynamic agricultural landscapes they inhabit. We used population genetic analyses of a severe crop pest, a member of the Bemisia tabaci (Hemiptera: Sternorrhyncha: Aleyrodoidea: Aleyrodidea) cryptic species complex known as Middle East-Asia Minor 1 (commonly known as biotype B), to estimate spatial and temporal genetic diversity over four months of the 2006-2007 summer growing season. We examined 559 individuals from eight sites, which were scored for eight microsatellite loci. Temporal genetic structure greatly exceeded spatial structure. There was significant temporal change in local genetic composition from the beginning to the end of the season accompanied by heterozygote deficits and inbreeding. This temporal structure suggests entire cohorts of pests can occupy a large and variable agricultural landscape but are rapidly replaced. These rapid genetic fluctuations reinforce the concept that agricultural landscapes are dynamic mosaics in time and space and may contribute to better decisions for pest and insecticide resistance management.

  15. Comparative Analysis of Population Genetic Structure in Bemisia tabaci (Gennadius) Biotypes B and Q Based on ISSR Marker

    Institute of Scientific and Technical Information of China (English)

    CHU Dong; WAN Fang-hao; XU Bao-yun; WU Qing-jun; ZHANG You-jun

    2008-01-01

    Bemisia tabaci (Gennadius) biotypes B and Q are two invasive biotypes in the species complex. The comparison of the population genetic structure of the two biotypes is of significance to show their invasive mechanism and to their control. The intersimple sequence repeats (ISSR) marker was used to analyze the 16 B-biotype populations and 4 Q-biotype populations worldwide with a Trialeurodes vaporariorum population in Shanxi Province, China, and a B. tabaci non-B/Q-biotype population in Zhejiang Province, China, was used as control populations. The analysis of genetic diversity showed that the diversity indexes of biotype Q including Nei's gene diversity index, Shannon informative index, and the percentage of polymorphic loci were higher than those of biotype B. The high genetic diversity of biotype Q might provide the genetic basis for the excellent ecological adaptation. Cluster analysis suggested that the ISSR could not be used in the phylogenetic analysis though it could easily distinguish the biotypes of B. tabaci. The difference of the population genetic structure between the biotype B and the biotype Q exists based on the ISSR marker. Meanwhile, the results suggested that the molecular marker has its limitation in the phylogenetic analysis among the biotypes of B. tabaci.

  16. Molecular cloning of the sex-related gene PSI in Bemisia tabaci and its alternative splicing properties.

    Science.gov (United States)

    Liu, Yating; Xie, Wen; Yang, Xin; Guo, Litao; Wang, Shaoli; Wu, Qingjun; Yang, Zezhong; Zhou, Xuguo; Zhang, Youjun

    2016-04-15

    The P-element somatic inhibitor (PSI) is gene known to regulate the transcription of doublesex (dsx) when transformer (tra) is absent in Bombyx mori. In this study, we identified and characterized a PSI homolog in Bemisia tabaci (BtPSI). BtPSI cDNA had a total length of 5700 bp and contained a predicted open reading frame (ORF) of 2208 nucleotides encoding for 735 amino acids. Multiple sequence alignments of the common regions of PSI proteins from B. tabaci and five other insect species revealed a high degree of sequence conservation. BtPSI is expressed in all stages of B. tabaci development, and expression did not significantly differ between female and male adult. A total of 92 BtPSI isoforms (78 in female and 22 in male) were identified, and a marker indicating the female-specific form was found. These results increase the understanding of genes that may determine sex in B. tabaci and provide a foundation for research on the sex determination mechanism in this insect.

  17. [Effects of calcium fertilizer on the development, survival, and feeding of B-biotype Bemisia tabaci on Euphorbia pulcherrima].

    Science.gov (United States)

    Huang, Jun; Zhang, Juan; Yu, Yong-Ming; Liu, Jian-Xin; Li, Ming-Jiang; Zhu, Kai-Yuan

    2012-09-01

    This paper studied the development, survival, and feeding of B-biotype Bemisia tabaci on Euphorbia pulcherrima under the conditions of 26 +/- 1 degrees C and 60% - 80% relative humidity after applying calcium fertilizer, taking applying fresh water as the control. There existed significant differences in the developmental duration of B. tabaci between treatment applying calcium fertilizer and the control. After applying calcium fertilizer, the egg stage of B. tabaci shortened significantly, and the development from egg to adult took 20.18 days (for the control, it took 18.72 days). However, there were no significant differences in the survival rates of B. tabaci at different development stages between the two treatments. The feeding of B. tabaci on E. pulcherrima induced the plant leaf chlorophyll fluorescence parameters changed, i. e., the photochemical efficiency (Fv/Fm), photochemical quenching coefficient (q(p)), light use efficiency (alpha), maximum photosynthesis rate (rETRmax), and tolerance to light (I(k)) decreased significantly, while the non-photochemical quenching coefficient (NPQ) had a significant increase. After applying calcium fertilizer, the plant leaf photoinhibition parameter (beta), rETRmax, and I(k) had less difference with th e control. The nail polish blot observation on the lower epidermis structure of plant leaf showed that calcium fertilizer could effectively compensate the decrease in the photosynthesis of E. pulcherrima damaged by B-biotype B. tabaci.

  18. Taxonomic status of the Bemisia tabaci complex (Hemiptera: Aleyrodidae and reassessment of the number of its constituent species.

    Directory of Open Access Journals (Sweden)

    Wonhoon Lee

    Full Text Available Bemisia tabaci (Hemiptera: Aleyrodidae is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1% than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%. This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1 was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex.

  19. Transcriptome profiling of the whitefly Bemisia tabaci reveals stage-specific gene expression signatures for thiamethoxam resistance.

    Science.gov (United States)

    Yang, N; Xie, W; Jones, C M; Bass, C; Jiao, X; Yang, X; Liu, B; Li, R; Zhang, Y

    2013-10-01

    Bemisia tabaci has developed high levels of resistance to many insecticides including the neonicotinoids and there is strong evidence that for some compounds resistance is stage-specific. To investigate the molecular basis of B. tabaci resistance to the neonicotinoid thiamethoxam we used a custom whitefly microarray to compare gene expression in the egg, nymph and adult stages of a thiamethoxam-resistant strain (TH-R) with a susceptible strain (TH-S). Gene ontology and bioinformatic analyses revealed that in all life stages many of the differentially expressed transcripts encoded enzymes involved in metabolic processes and/or metabolism of xenobiotics. Several of these are candidate resistance genes and include the cytochrome P450 CYP6CM1, which has been shown to confer resistance to several neonicotinoids previously, a P450 belonging to the Cytochrome P450s 4 family and a glutathione S-transferase (GST) belonging to the sigma class. Finally several ATP-binding cassette transporters of the ABCG subfamily were highly over-expressed in the adult stage of the TH-R strain and may play a role in resistance by active efflux. Here, we evaluated both common and stage-specific gene expression signatures and identified several candidate resistance genes that may underlie B. tabaci resistance to thiamethoxam.

  20. Relative influence of plant quality and natural enemies on the seasonal dynamics of Bemisia tabaci (Hemiptera: Aleyrodidae) in cotton.

    Science.gov (United States)

    Asiimwe, Peter; Naranjo, Steven E; Ellsworth, Peter C

    2013-06-01

    The abundance and distribution of insect herbivores is determined by, among other things, plant quality and natural enemies. These two factors vary temporally and spatially, subsequently affecting seasonal population dynamics. The relative influence of plant quality and natural enemies on the seasonal dynamics of Bemisia tabaci (Gennadius) was investigated in a 3-yr field study in cotton. Plant quality was manipulated through varying irrigation regimes: irrigations done at 20, 40, and 60% soil water depletions; and natural enemy densities were manipulated using broad spectrum insecticide applications that reduced their densities compared with unsprayed controls. In each year, densities of B. tabaci eggs, large nymphs and adults were consistently higher when natural enemy densities were reduced compared with when they were left unaltered, regardless of irrigation regime. In contrast, effects of plant quality on densities of all whitefly stages were weak and inconsistent. In addition, natural enemy densities and predator:prey ratios also were not generally affected by plant quality. Interactions between natural enemies and plant quality on whitefly dynamics were rare. In general, whitefly densities were elevated two-thirds of the time and increased two- to sixfold when natural enemy densities were reduced compared with plant quality effects which influenced whitefly densities about one-third of the time and were expressed inconsistently over the years. This indicates that natural enemies exert a comparatively greater influence on seasonal dynamics of B. tabaci in cotton than plant quality, as manipulated by differential irrigation.

  1. Toxicological and biochemical basis of synergism between the entomopathogenic fungus Lecanicillium muscarium and the insecticide matrine against Bemisia tabaci (Gennadius)

    Science.gov (United States)

    Ali, Shaukat; Zhang, Can; Wang, Zeqing; Wang, Xing-Min; Wu, Jian-Hui; Cuthbertson, Andrew G. S.; Shao, Zhenfang; Qiu, Bao-Li

    2017-04-01

    The sweetpotato whitefly Bemisia tabaci (Gennadius) was challenged with different combinations of matrine (insecticide) and Lecanicillium muscarium (entomopathogenic fungus). Our results revealed a synergistic relationship between matrine and L. muscarium on mortality and enzyme activities of B. tabaci. To illustrate the biochemical mechanisms involved in detoxification and immune responses of B. tabaci against both control agents, activities of different detoxifying and antioxidant enzymes were quantified. After combined application of matrine and L. muscarium, activities of carboxylestrease (CarE), glutathione-s-transferase (GSTs) and chitinase (CHI) decreased during the initial infection period. Acetylcholinestrase (AChE) activities increased during the entire experimental period, whereas those of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) decreased during the later infection period. The increased mortality and suppression of enzymatic response of B. tabaci following matrine and L. muscarium application suggests a strong synergistic effect between both agents. The strong synergistic effect is possibly related to the disturbance of acetylcholine balance and changes in AchE activities of the whitefly as both matrine and L. muscarium target insect acetylcholine (Ach) receptors which in turn effects AchE production. Therefore, our results have revealed the complex biochemical processes involved in the synergistic action of matrine and L. muscarium against B. tabaci.

  2. Effects of host, temperature and relative humidity on competitive displacement of two invasive Bemisia tabaci biotypes [Q and B

    Institute of Scientific and Technical Information of China (English)

    Dong Chu; Yun-Li Tao; You-Jun Zhang; Fang-Hao Wan; Judith K Brown

    2012-01-01

    Bemisia tabaci shifted unexpectedly in China from a predominance of B biotype to Q biotype during 2005-2008.This observation stimulated an interest in investigating whether environmental factors,including host,temperature and relative humidity (RH) could possibly explain the observed shift in biotypes distribution.Results indicated that all three parameters examined influenced biotype survivability.The percentage of B biotype,when reared together on pepper plants with the Q biotype,decreased significantly from 66.7% in the founder population,to 13.6% and 3.7% in the first and second generations,respectively.When the B (founder at 66.7%) and Q (founder at 33.3%) biotypes were reared together on eggplant alone,or on pepper-plus-eggplant combination,the population size of the B biotype either remained constant,or increased somewhat in the first and second generations.On eggplant,the effects of RH and temperature on the competitiveness between the Q and B biotypes (3 pairs of Q and 6 pairs of B) were not significant.

  3. Taxonomic status of the Bemisia tabaci complex (Hemiptera: Aleyrodidae) and reassessment of the number of its constituent species.

    Science.gov (United States)

    Lee, Wonhoon; Park, Jongsun; Lee, Gwan-Seok; Lee, Seunghwan; Akimoto, Shin-ichi

    2013-01-01

    Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1%) than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%). This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1) was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex.

  4. Location of Symbionts in the Whitefly Bemisia tabaci Affects Their Densities during Host Development and Environmental Stress

    Science.gov (United States)

    Su, Qi; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Ghanim, Murad; Zhang, Youjun

    2014-01-01

    Bacterial symbionts often enhance the physiological capabilities of their arthropod hosts and enable their hosts to expand into formerly unavailable niches, thus leading to biological diversification. Many arthropods, including the worldwide invasive whitefly Bemisia tabaci, have individuals simultaneously infected with symbionts of multiple genera that occur in different locations in the host. This study examined the population dynamics of symbionts that are located in different areas within B. tabaci. While densities of Portiera and Hamiltonella (which are located in bacteriocytes) appeared to be well-regulated during host development, densities of Rickettsia (which are not located in bacteriocytes) were highly variable among individual hosts during host development. Host mating did not significantly affect symbiont densities. Infection by Tomato yellow leaf curl virus did not affect Portiera and Hamiltonella densities in either sex, but increased Rickettsia densities in females. High and low temperatures did not affect Portiera and Hamiltonella densities, but low temperature (15°C) significantly suppressed Rickettsia densities whereas high temperature (35°C) had little effect on Rickettsia densities. The results are consistent with the view that the population dynamics of bacterial symbionts in B. tabaci are regulated by symbiont location within the host and that the regulation reflects adaptation between the bacteria and insect. PMID:24632746

  5. Comparison of transmission of Papaya leaf curl China virus among four cryptic species of the whitefly Bemisia tabaci complex

    Science.gov (United States)

    Guo, Tao; Guo, Qi; Cui, Xi-Yun; Liu, Yin-Quan; Hu, Jian; Liu, Shu-Sheng

    2015-01-01

    Begomoviruses are transmitted by cryptic species of the whitefly Bemisia tabaci complex, often in a species-specific manner. Papaya leaf curl China virus (PaLCuCNV) has been recorded to infect several crops including papaya, tomato and tobacco in China. To help assess the risks of spread of this virus, we compared the acquisition, retention and transmission of PaLCuCNV among four species of whiteflies, Middle East-Asia Minor 1 (MEAM1), Mediterranean (MED), Asia 1 and Asia II 7. All four species of whiteflies are able to acquire, retain and transmit the virus, but with different levels of efficiency. Transmission tests using tomato as the host plant showed that MEAM1 transmitted PaLCuCNV with substantially higher efficiency than did MED, Asia 1 and Asia II 7. Furthermore, accumulation of PaLCuCNV in the whiteflies was positively associated with its efficiency of transmitting the virus. Altogether, these findings indicate that MEAM1 is the most efficient vector for PaLCuCNV in the four species of whiteflies, and suggest that risks of PaLCuCNV pandemics are high in regions where MEAM1 occurs. PMID:26486606

  6. Genome-Wide Characterization and Expression Profiling of Sugar Transporter Family in the Whitefly, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Zezhong Yang

    2017-05-01

    Full Text Available Sugar transporters (STs play pivotal roles in the growth, development, and stress responses of phloem-sucking insects, such as the whitefly, Bemisia tabaci. In this study, 137 sugar transporters (STs were identified based on analysis of the genome and transcriptome of B. tabaci MEAM1. B. tabaci MEAM1 encodes a larger number of STs than other selected insects. Phylogenetic and molecular evolution analysis showed that the 137 STs formed three expanded clades and that the genes in Sternorrhyncha expanded clades had accelerated rates of evolution. B. tabaci sugar transporters (BTSTs were divided into three groups based on their expression profiles across developmental stages; however, no host-specific BTST was found in B. tabaci fed on different host plants. Feeding of B. tabaci adults with feeding diet containing dsRNA significantly reduced the transcript level of the target genes in B. tabaci and mortality was significantly improved in B. tabaci fed on dsRNA compared to the control, which indicates the sugar transporters may be used as potential RNAi targets for B. tabaci bio-control. These results provide a foundation for further studies of STs in B. tabaci.

  7. Preference of Bemisia tabaci biotype B on zucchini squash and buckwheat and the effect of Delphastus catalinae on whitefly populations.

    Science.gov (United States)

    Razze, Janine M; Liburd, Oscar E; McSorley, Robert

    2016-07-01

    Zucchini squash, Cucurbita pepo L., is an important vegetable crop in Florida. Physiological disorders and insect-transmitted diseases are major problems for squash growers in semi-tropical regions around the world. Bemisia tabaci (Gennadius) biotype B is a significant whitefly pest and is largely responsible for transmitting viruses and causing physiological disorders in squash. Several studies have shown that whitefly populations are reduced when crops are interplanted with non-host cover crops or mulches. The aim of the present study was to determine how the presence of buckwheat, Fagopyrum esculentum Moench, and a key predator, Delphastus catalinae (Horn), affect whitefly colonization on squash. Whitefly densities were higher on squash than on buckwheat. The introduction of D. catalinae on squash significantly reduced whitefly populations. Overall, there were higher densities of D. catalinae on squash where the whitefly pest was more concentrated compared with buckwheat. The study provided preliminary evidence that D. catalinae, when used in conjunction with buckwheat as a living mulch, may aid in reducing whiteflies in squash. This greenhouse experiment highlights the need to investigate a multitactic approach of intercropping buckwheat with squash and the incorporation of D. catalinae in the field to manage populations of whiteflies and whitefly-transmitted diseases. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  8. Reference gene selection for qRT-PCR analysis in the sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Li, Rumei; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Yang, Nina; Yang, Xin; Pan, Huipeng; Zhou, Xiaomao; Bai, Lianyang; Xu, Baoyun; Zhou, Xuguo; Zhang, Youjun

    2013-01-01

    Accurate evaluation of gene expression requires normalization relative to the expression of reliable reference genes. Expression levels of "classical" reference genes can differ, however, across experimental conditions. Although quantitative real-time PCR (qRT-PCR) has been used extensively to decipher gene function in the sweetpotato whitefly Bemisia tabaci, a world-wide pest in many agricultural systems, the stability of its reference genes has rarely been validated. In this study, 15 candidate reference genes from B. tabaci were evaluated using two Excel-based algorithms geNorm and Normfinder under a diverse set of biotic and abiotic conditions. At least two reference genes were selected to normalize gene expressions in B. tabaci under experimental conditions. Specifically, for biotic conditions including host plant, acquisition of a plant virus, developmental stage, tissue (body region of the adult), and whitefly biotype, ribosomal protein L29 was the most stable reference gene. In contrast, the expression of elongation factor 1 alpha, peptidylprolyl isomerase A, NADH dehydrogenase, succinate dehydrogenase complex subunit A and heat shock protein 40 were consistently stable across various abiotic conditions including photoperiod, temperature, and insecticide susceptibility. Our finding is the first step toward establishing a standardized quantitative real-time PCR procedure following the MIQE (Minimum Information for publication of Quantitative real time PCR Experiments) guideline in an agriculturally important insect pest, and provides a solid foundation for future RNA interference based functional study in B. tabaci.

  9. Flupyradifurone effectively manages whitefly Bemisia tabaci MED (Hemiptera: Aleyrodidae) and tomato yellow leaf curl virus in tomato.

    Science.gov (United States)

    Roditakis, Emmanouil; Stavrakaki, Marianna; Grispou, Maria; Achimastou, Aikaterini; Van Waetermeulen, Xavier; Nauen, Ralf; Tsagkarakou, Anastasia

    2017-08-01

    The cotton whitefly Bemisia tabaci (Gennadius) is among the most important pests of numerous crops and a vector of more than 100 plant viruses, causing significant crop losses worldwide. Managing this pest as well as inhibiting the transmission of major viruses such as tomato yellow leaf curl virus (TYLCV) are of utmost importance for sustainable yields. The efficacy against both whitefly and virus transmission of the novel systemic butenolide insecticide flupyradifurone was investigated in this study. The inhibition of TYLCV transmission by flupyradifurone was compared to that by thiamethoxam, a neonicotinoid insecticide reported to inhibit virus transmission. The experiment was performed under high virus pressure conditions (10 viruliferous insects per plant for 48 h) using a fully characterized field strain of B. tabaci. The insecticides were foliarly applied at recommended label rates under greenhouse conditions. Flupyradifurone suppressed virus transmission by 85% while levels of suppression after thiamethoxam treatments were just 25% and significantly lower. In untreated control plots, 100% of plants were infected by TYLCV. The observed difference in the potential to suppress virus transmission is linked to a strong knockdown effect as well as prolonged feeding inhibition in flupyradifurone treatments. Flupyradifurone is shown to be an extremely useful, fast-acting, new chemical tool in integrated crop management offering simultaneous control of whiteflies and strong suppression of viral infections via its rapid knockdown action and good residual activity. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Reproduction of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) B biotype in maize fields (Zea mays L.) in Brazil.

    Science.gov (United States)

    Quintela, Eliane D; Abreu, Aluana G; Lima, Julyana F Dos S; Mascarin, Gabriel M; Santos, Jardel B Dos; Brown, Judith K

    2016-11-01

    Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) was observed to have completed its reproductive cycle from the egg to the adult on maize (Zea mays L.). Field and screenhouse studies were carried out to investigate the durability of this putative and unprecedented adaptation to a grass host. Analysis of the mitochondrial COI gene sequence identified the maize-associated B. tabaci as the exotic B biotype (major clade North Africa-Mediterranean-Middle East). Results showed that whiteflies migrated from soybean crops and successfully established in maize plants. Females exhibited a preference for oviposition primarily on the first and second leaves of maize, but were also able to colonise developing leaves. A high, natural infestation on maize (193.3 individuals, all developmental stages) was observed within a 7.1 cm(2) designated 'observation area'. Whiteflies collected from naturally infested maize leaves and allowed to oviposit on maize seedlings grown in a screenhouse developed from egg to adulthood in 28.6 ± 0.2 days. This is the first report of the B biotype completing its development on maize plants. This surprising anomaly indicates that the B biotype is capable of adapting to monocotyledonous host plants, and importantly, broadens the host range to include at least one species in the Poaceae. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Use of the synergist piperonyl butoxide can slow the development of alpha-cypermethrin resistance in the whitefly Bemisia tabaci.

    Science.gov (United States)

    Zimmer, C T; Panini, M; Singh, K S; Randall, E L; Field, L M; Roditakis, E; Mazzoni, E; Bass, C

    2017-04-01

    The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid (alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear. © 2016 The Royal Entomological Society.

  12. Genome-Wide Characterization and Expression Profiling of Sugar Transporter Family in the Whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Yang, Zezhong; Xia, Jixing; Pan, Huipeng; Gong, Cheng; Xie, Wen; Guo, Zhaojiang; Zheng, Huixin; Yang, Xin; Yang, Fengshan; Wu, Qingjun; Wang, Shaoli; Zhang, Youjun

    2017-01-01

    Sugar transporters (STs) play pivotal roles in the growth, development, and stress responses of phloem-sucking insects, such as the whitefly, Bemisia tabaci. In this study, 137 sugar transporters (STs) were identified based on analysis of the genome and transcriptome of B. tabaci MEAM1. B. tabaci MEAM1 encodes a larger number of STs than other selected insects. Phylogenetic and molecular evolution analysis showed that the 137 STs formed three expanded clades and that the genes in Sternorrhyncha expanded clades had accelerated rates of evolution. B. tabaci sugar transporters (BTSTs) were divided into three groups based on their expression profiles across developmental stages; however, no host-specific BTST was found in B. tabaci fed on different host plants. Feeding of B. tabaci adults with feeding diet containing dsRNA significantly reduced the transcript level of the target genes in B. tabaci and mortality was significantly improved in B. tabaci fed on dsRNA compared to the control, which indicates the sugar transporters may be used as potential RNAi targets for B. tabaci bio-control. These results provide a foundation for further studies of STs in B. tabaci.

  13. Competitive ability and fitness differences between two introduced populations of the invasive whitefly Bemisia tabaci Q in China.

    Science.gov (United States)

    Fang, Yi-Wei; Liu, Ling-Yun; Zhang, Hua-Li; Jiang, De-Feng; Chu, Dong

    2014-01-01

    Our long-term field survey revealed that the Cardinium infection rate in Bemisia tabaci Q (also known as biotype Q) population was low in Shandong, China over the past few years. We hypothesize that (1) the Cardinium-infected (C+) B. tabaci Q population cannot efficiently compete with the Cardinium-uninfected (C-) B. tabaci Q population; (2) no reproductive isolation may have occurred between C+ and C-; and (3) the C- population has higher fitness than the C+ population. To reveal the differences in competitive ability and fitness between the two introduced populations (C+ and C-), competition between C+ and C- was examined over several generations. Subsequently, the reproductive isolation between C+ and C- was studied by crossing C+ with C- individuals, and the fitnesses of C+ and C- populations were compared using a two-sex life table method. Our results demonstrate that the competitive ability of the C+ whiteflies was weaker than that of C-. There is that no reproductive isolation occurred between the two populations and the C- population had higher fitness than the C+ population. The competitive ability and fitness differences of two populations may explain why C- whitefly populations have been dominant during the past few years in Shandong, China. However, the potential role Cardinium plays in whitefly should be further explored.

  14. Toxicity of sucrose octanoate to egg, nymphal, and adult Bemisia tabaci (Hemiptera: Aleyrodidae) using a novel plant-based bioassay.

    Science.gov (United States)

    McKenzie, C L; Weathersbee, A A; Puterka, Gary J

    2005-08-01

    The sweetpotato whitefly, Bemisia tabaci (Gennadius), B biotype, presents a unique problem for vegetable growers by serving as a vector of plant viruses and by inducing physiological disorders of leaves and fruit. An action threshold of a single whitefly is necessary because of the threat of disease in many areas and growers rely heavily on a single class of insecticides (neonicotinoids) for whitefly control. Additional control methods are needed to manage this pest in commercial vegetables. Extracts of wild tobacco contain natural sugar esters that have previously been shown effective in controlling many soft-bodied insects. We developed a novel tomato leaf bioassay system to assess a synthetic sugar ester derivative, sucrose octanoate, for insecticidal activity against the eggs, nymphs, and adults of B. tabaci. The LC50 values for sucrose octanoate against adults, second instars, and fourth instars of the whitefly were 880, 686, and 1,571 ppm, respectively. The LC50 against whitefly eggs was higher (11,446 ppm) but indicated that some egg mortality occurred at the recommended application rate of 0.8-1.2% (3,200-4,800 ppm [Al]). Toxicity of sugar esters to whitefly eggs has not been reported previously. The tomato leaf bioassay produced reliable and repeatable results for whitefly toxicity studies and predicted that effective nymph and adult whitefly control can be achieved with sucrose octanoate at application rates < or = 1% (4,000 ppm [AI]). Field efficacy studies are warranted to determine whether this biorational pesticide has application in commercial tomato production.

  15. Rapid accumulation and low degradation: key parameters of Tomato yellow leaf curl virus persistence in its insect vector Bemisia tabaci.

    Science.gov (United States)

    Becker, Nathalie; Rimbaud, Loup; Chiroleu, Frédéric; Reynaud, Bernard; Thébaud, Gaël; Lett, Jean-Michel

    2015-12-02

    Of worldwide economic importance, Tomato yellow leaf curl virus (TYLCV, Begomovirus) is responsible for one of the most devastating plant diseases in warm and temperate regions. The DNA begomoviruses (Geminiviridae) are transmitted by the whitefly species complex Bemisia tabaci. Although geminiviruses have long been described as circulative non-propagative viruses, observations such as long persistence of TYLCV in B. tabaci raised the question of their possible replication in the vector. We monitored two major TYLCV strains, Mild (Mld) and Israel (IL), in the invasive B. tabaci Middle East-Asia Minor 1 cryptic species, during and after the viral acquisition, within two timeframes (0-144 hours or 0-20 days). TYLCV DNA was quantified using real-time PCR, and the complementary DNA strand of TYLCV involved in viral replication was specifically quantified using anchored real-time PCR. The DNA of both TYLCV strains accumulated exponentially during acquisition but remained stable after viral acquisition had stopped. Neither replication nor vertical transmission were observed. In conclusion, our quantification of the viral loads and complementary strands of both Mld and IL strains of TYLCV in B. tabaci point to an efficient accumulation and preservation mechanism, rather than to a dynamic equilibrium between replication and degradation.

  16. Dynamics of Bemisia tabaci biotypes and insecticide resistance in Fujian province in China during 2005–2014

    Science.gov (United States)

    Yao, Feng-Luan; Zheng, Yu; Huang, Xiao-Yan; Ding, Xue-Ling; Zhao, Jian-Wei; Desneux, Nicolas; He, Yu-Xian; Weng, Qi-Yong

    2017-01-01

    The whitefly Bemisia tabaci (Gennadius) is an important agricultural insect pest worldwide. The B and Q biotypes are the two most predominant and devastating biotypes prevalent across China. However, there are few studies regarding the occurrence of the Q biotype in Fujian Province, China, where high insecticide resistance has been reported in the B biotype. Differences in some biological characteristics between the B and Q biotypes, especially insecticide resistance, are considered to affect the outcome of their competition. Extensive surveys in Fujian revealed that the B biotype was predominant during 2005–2014, whereas the Q biotype was first detected in some locations in 2013 and widely detected throughout the province in 2014. Resistance to neonicotinoids (that have been used for more than 10 years) exhibited fluctuations in open fields, but showed a continual increasing trend in protected areas. Resistance to lambda-cyhalothrin, chlorpyrifos, and abamectin exhibited a declining trend. Resistance to novel insecticides, such as nitenpyram, pymetrozine, sulfoxaflor, and cyantraniliprole, in 2014 was generally below a moderate level. A decline in insecticide resistance in the B biotype and the rapid buildup of protected crops under global temperature increase may have promoted the establishment of the Q biotype in Fujian. PMID:28112233

  17. Morphological characterization of Capsicum annuum L. accessions from southern Mexico and their response to the Bemisia tabaci-Begomovirus complex

    Directory of Open Access Journals (Sweden)

    Horacio Ballina-Gomez

    2013-12-01

    Full Text Available The high diversity of chili pepper (Capsicum annuum L. in Mexico offers an excellent alternative to search for wild and semi-domesticated genotypes as sources of resistance to the complex Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae-Begomovirus, which has caused enormous losses in commercial production of various horticultural crops. The goal of the present work was to characterize ex situ 18 genotypes of C. annuum from southern Mexico through 47 morphological descriptors, and to evaluate its response to the B. tabaci-Begomovirus complex. Morphological characterization showed the variables calyx annular constriction (CAC, number of branch bifurcation (NBB, and calyx pigmentation (CP had the highest variation. Principal components analysis (PCA of 47 morphological characteristics showed that 12 components were selected as meaningful factors. These components explained 94% of the variation. Cluster analysis showed three major clusters and seven sub-clusters. On the other hand, evaluation of the response to B. tabaci-Begomovirus showed that the genotypes have differential susceptibility to this vector-pathogen complex. Genotypes 'Chawa', 'Blanco', 'Maax' and 'X'catic' were into the low susceptibility to B. tabaci and low severity of viral symptoms. Surprisingly, the genotype 'Simojovel' showed high susceptibility to whitefly, but was grouped into genotypes with low symptom severity. This study shows the potential of native germplasm of pepper to explore sources of resistance to the B. tabaci-Begomovirus complex.

  18. Estimation of the Whitefly Bemisia tabaci Genome Size Based on k-mer and Flow Cytometric Analyses

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    Wenbo Chen

    2015-07-01

    Full Text Available Whiteflies of the Bemisia tabaci (Hemiptera: Aleyrodidae cryptic species complex are among the most important agricultural insect pests in the world. These phloem-feeding insects can colonize over 1000 species of plants worldwide and inflict severe economic losses to crops, mainly through the transmission of pathogenic viruses. Surprisingly, there is very little genomic information about whiteflies. As a starting point to genome sequencing, we report a new estimation of the genome size of the B. tabaci B biotype or Middle East-Asia Minor 1 (MEAM1 population. Using an isogenic whitefly colony with over 6500 haploid male individuals for genomic DNA, three paired-end genomic libraries with insert sizes of ~300 bp, 500 bp and 1 Kb were constructed and sequenced on an Illumina HiSeq 2500 system. A total of ~50 billion base pairs of sequences were obtained from each library. K-mer analysis using these sequences revealed that the genome size of the whitefly was ~682.3 Mb. In addition, the flow cytometric analysis estimated the haploid genome size of the whitefly to be ~690 Mb. Considering the congruency between both estimation methods, we predict the haploid genome size of B. tabaci MEAM1 to be ~680–690 Mb. Our data provide a baseline for ongoing efforts to assemble and annotate the B. tabaci genome.

  19. Identification and expression profile analysis of odorant binding protein and chemosensory protein genes in Bemisia tabaci MED by head transcriptome

    Science.gov (United States)

    Zhang, Wei; Zhang, Xiaoman; Qu, Cheng; Tetreau, Guillaume; Sun, Lujuan; Zhou, Jingjiang

    2017-01-01

    Odorant binding proteins (OBPs) and chemosensory proteins (CSPs) of arthropods are thought to be involved in chemical recognition which regulates pivotal behaviors including host choice, copulation and reproduction. In insects, OBPs and CSPs located mainly in the antenna but they have not been systematically characterized yet in Bemisia tabaci which is a cryptic species complex and could damage more than 600 plant species. In this study, among the 106,893 transcripts in the head assembly, 8 OBPs and 13 CSPs were identified in B. tabaci MED based on head transcriptomes of adults. Phylogenetic analyses were conducted to investigate the relationships of B. tabaci OBPs and CSPs with those from several other important Hemipteran species, and the motif-patterns between Hemiptera OBPs and CSPs were also compared by MEME. The expression profiles of the OBP and CSP genes in different tissues of B. tabaci MED adults were analyzed by real-time qPCR. Seven out of the 8 OBPs found in B. tabaci MED were highly expressed in the head. Conversely, only 4 CSPs were enriched in the head, while the other nine CSPs were specifically expressed in other tissues. Our findings pave the way for future research on chemical recognition of B. tabaci at the molecular level. PMID:28166541

  20. [Effects of alcohol extracts from three kinds of biomass energy plant tissues on biological activity of Bemisia tabaci].

    Science.gov (United States)

    Zhou, Fu-cai; Zhou, Gui-sheng; Li, Chuan-ming; Yang, Yi-zhong; Qin, Pei

    2009-03-01

    To test the feasibility of using raw extracts from the tissues of biomass energy plants Ricinus communi and Kosteletzkya virginica as plant protection agents, the alcohol extracts from R. communi seed and leaf and from K. virginica leaf were used to treat adult Bemisia tabaci by spraying. The glutathione S-transferase and carboxylesterase activities in B. tabaci body were measured after treated for 4 h, 24 h, 48 h, 72 h, and 96 h, and the olfaction responses of B. tabaci to the alcohol extracts were detected with a Y-tube olfactomet. All the three alcohol extracts obviously inhibited the glutathione S-transferase and carboxylesterase activities in a concentration-dependent manner. The inhibitory effect of the 250-times diluted alcohol extracts on the two enzyme activities was equivalent to that of 3000 times-diluted 1.8% avermectins. In addition, the 250-times diluted alcohol extracts had obvious repellent effect on B. tabaci, with the repellent coefficient of the alcohol extracts from R. communi seed and leaf and from K, virginica leaf being 100.0%, 96.7%, and 79.4%, respectively. All of these suggested that the test three alcohol extracts had repellent and other biological effects on B. tabaci.

  1. Development and reproduction of ‘B' biotype Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) on four ornamentals

    Institute of Scientific and Technical Information of China (English)

    LILIN; SHUN-XIANGREN

    2005-01-01

    Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ±1℃; relative humidity 75%-90%; L: D 14:10). The total survivorship from egg to adult on hibiscus (Hibiscus rosa-sinensis L.), poinsettia (Euphorbia pulcherrima Will), cottonrose hibiscus (Hibiscus mutabilis L.) and variegated leafcroton (Codiaeum variegatum ‘Aucubaefolium') were 33.69%, 40.55%, 79.11%, and 29.39%,respectively. The developmental periods from egg to adult varied from 23.12 days on cottonrose hibiscus to 32.13 days on hibiscus. The average longevity of adult females ranged from 6.87 days on variegated leafcroton to 21.07 days on poinsettia. The average numbers of eggs laid per female were 9.20, 25.13, 54.45, and 26.79 on the above respective hosts. The intrinsic rates of natural increase (rm) for B biotype B. tabaci on cottonrose hibiscus was the highest. Based on life table analyses of whitefly populations, cottonrose hibiscus was the most suitable host for B biotype B. tabaci in this study.

  2. The presence of six cryptic species of the whitefly Bemisia tabaci complex in China as revealed by crossing experiments

    Institute of Scientific and Technical Information of China (English)

    Peng Wang; Di-Bing Sun; Bao-Li Qiu; Shu-Sheng Liu

    2011-01-01

    Recent phylogenetic analysis using mitochondrial cytochrome oxidase I(mtCOI)sequences of Bemisia tabaci worldwide indicates that the whitefly comprises at least 24 morphologically indistinguishable but genetically distinct cryptic species.While evidence of reproductive isolation has been reported for some of the putative species,more extensive crossing experiments are required to clarify the systematics of this species complex.In this study,we established laboratory cultures for six putative species of B.tabaci collected in China.We conducted 22 inter-species crosses among the six putative species.The data and those reported previously were collated,and the combined dataset covered all the 30 possible inter-species crosses among the six putative species.Intra-species controls always produced female and male progeny and the proportions of females in the first generation(F1)ranged from 56% to 70%.However,in inter-species crosses female progeny were rarely produced,and the few F1 females produced in four of the 30 inter-species crosses were either sterile or significantly weaker in viability.These results demonstrate a pattern of complete reproductive isolation among the six putative species and show that they are six cryptic species in the B.tabaci complex.

  3. Reference gene selection for qRT-PCR analysis in the sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae.

    Directory of Open Access Journals (Sweden)

    Rumei Li

    Full Text Available BACKGROUND: Accurate evaluation of gene expression requires normalization relative to the expression of reliable reference genes. Expression levels of "classical" reference genes can differ, however, across experimental conditions. Although quantitative real-time PCR (qRT-PCR has been used extensively to decipher gene function in the sweetpotato whitefly Bemisia tabaci, a world-wide pest in many agricultural systems, the stability of its reference genes has rarely been validated. RESULTS: In this study, 15 candidate reference genes from B. tabaci were evaluated using two Excel-based algorithms geNorm and Normfinder under a diverse set of biotic and abiotic conditions. At least two reference genes were selected to normalize gene expressions in B. tabaci under experimental conditions. Specifically, for biotic conditions including host plant, acquisition of a plant virus, developmental stage, tissue (body region of the adult, and whitefly biotype, ribosomal protein L29 was the most stable reference gene. In contrast, the expression of elongation factor 1 alpha, peptidylprolyl isomerase A, NADH dehydrogenase, succinate dehydrogenase complex subunit A and heat shock protein 40 were consistently stable across various abiotic conditions including photoperiod, temperature, and insecticide susceptibility. CONCLUSION: Our finding is the first step toward establishing a standardized quantitative real-time PCR procedure following the MIQE (Minimum Information for publication of Quantitative real time PCR Experiments guideline in an agriculturally important insect pest, and provides a solid foundation for future RNA interference based functional study in B. tabaci.

  4. A Primary Screening and Applying of Plant Volatiles as Repellents to Control Whitefly Bemisia tabaci (Gennadius) on Tomato

    Science.gov (United States)

    Du, Wenxiao; Han, Xiaoqing; Wang, Yubo; Qin, Yuchuan

    2016-02-01

    With the goal of finding a new way to reduce population densities of Bemisia tabaci biotype Q in greenhouses, seven repellent volatile chemicals and their combinations were screened. The mixture of DLCO (D-limonene, citral and olive oil (63:7:30)) had a better cost performance(SC50 = 22.59 mg/ml)to repel whiteflies from settling than the other mixtures or single chemicals. In the greenhouse, in both the choice test and the no-choice tests, the number of adult whiteflies that settled on 1% DLCO-treated tomato plants was significantly lower than those settling on the control plants for the different exposure periods (P  0.05) between the number of eggs on treated and control plants in the no-choice test. Compared with the controls, 1% DLCO did not cause significantly statistic mortality rates (P > 0.05) out of different living stages of B. tabaci. The tests for evaluating the repellent efficacy, showed that a slow-releasing bottle containing the mixture had a period of efficacy of 29 days, and the application of this mixture plus a yellow board used as a push-pull strategy in the greenhouse was also effective.

  5. Phylogeographical structure in mitochondrial DNA of whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) in southern India and Southeast Asia.

    Science.gov (United States)

    Ram Kumar, Nikhil; Chang, Jian-Cheng; Narayanan, Manikanda Boopathi; Ramasamy, Srinivasan

    2016-03-29

    South and Southeast Asia endure high vegetable production losses due to begomovirus diseases mainly transmitted by the insect vector, whitefly (Bemisia tabaci). Control over the spread of virus infection can be achieved through a better understanding of genetic diversity among B. tabaci. A total of 64 populations of B. tabaci collected from Tamil Nadu (India), Vietnam, Thailand, and Indonesia were investigated based on mitochondrial cytochrome c oxidase I (coxI) sequences. Populations from Tamil Nadu are distributed into three clades (Asia I, Asia II 7, and Asia II 8), whereas Indonesian populations settle along with Asia I population of India in the phylogenetic tree. Vietnam populations align with the Middle East-Asia Minor 1 (MEAM1) clade, and interestingly MEAM1 invades northern Vietnam quite recently. Samples from Thailand made a unique clade between the outgroup and the remaining B. tabaci, representing the possibility of a new subspecies. AMOVA analysis among populations from various districts in Tamil Nadu exhibits significant differences, which represent each district's individuality. This study proves that the use of coxI as a marker for molecular identification of B. tabaci can provide a better estimate of diversity. We provide important clues for developing insight into the genetic structure of B. tabaci, and suggest strategies for control.

  6. Three Members of the Bemisia tabaci (Hemiptera: Aleyrodidae) Cryptic Species Complex Occur Sympatrically in Argentine Horticultural Crops.

    Science.gov (United States)

    Alemandri, V; Vaghi Medina, C G; Dumón, A D; Argüello Caro, E B; Mattio, M F; García Medina, S; López Lambertini, P M; Truol, G

    2015-04-01

    The whitefly, Bemisia tabaci (Gennadius), is a cryptic species complex that attacks >600 different species of plants and transmits several plant viruses causing severe economic losses. Until 2010, the B. tabaci complex comprised 24 distinct putative species. Recently, at least 15 new species have been reported. The objective of this study was to identify B. tabaci species present in bean, melon, and tomato crops in Argentina by applying phylogenetic analyses and pairwise comparison of genetic distances of mitochondrial cytochrome c oxidase subunit I (mtCOI) sequences. The 39 proposed whitefly species were identified with both analyses, and the presence in Argentina of one indigenous species, New World 2 (NW2), and two introduced species, Middle East-Asia Minor one (MEAM1) and Mediterranean, was confirmed. Common bean crop presented the three whitefly species detected, with NW2, MEAM1, and Mediterranean being present all together under field conditions. Also, Mediterranean was the only species identified in tomato, whereas MEAM1 was found in melon. To the best of our knowledge, Mediterranean is a recent invasive species in open-field agriculture in the American continent and in greenhouse tomato in Argentina. Additionally, we provide the first report of MEAM1 in common bean and melon. These findings raise several questions on the future scenario of B. tabaci and the viruses it transmits in Argentina.

  7. Effects of high-gossypol cotton on the development and reproduction of Bemisia tabaci (Hemiptera: Aleyrodidae) MEAM1 cryptic species.

    Science.gov (United States)

    Guo, Jian-Ying; Wu, Gang; Wan, Fang-Hao

    2013-06-01

    Use of plant secondary metabolic compounds is an important method for insect pest control. In this study, the survival, development, and reproduction of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) MEAM1 cryptic species were compared over two consecutive generations on three cotton cultivars of different gossypol levels. Both cotton cultivar and generation significantly affected the fitness of the whitefly. In both generations, the immature development times on the low-gossypol cultivar ZMS13 were significantly longer than those on the high-gossypol cultivar M9101 or medium-gossypol cultivar HZ401. The female fecundity and rate of population increase of the whitefly ranked in the following order: ZMS13 > HZ401 > M9101. On each cultivar, the immature development time was shorter and the immature survival rate was higher in the second generation than those in the first generation. Rate of increase was also higher in the second generation. These results demonstrated that the fitness of B. tabaci MEAM1 cryptic species on the low-gossypol cotton cultivar ZMS13 was higher than that on the medium- or high-gossypol cultivar. The comparison of the life histories of B. tabaci MEAM1 cryptic species on different cotton varieties is important for the development of an integrated pest management program of the whitefly by using plant secondary metabolic compounds.

  8. Two cytochrome P450 genes are involved in imidacloprid resistance in field populations of the whitefly, Bemisia tabaci, in China.

    Science.gov (United States)

    Yang, Xin; Xie, Wen; Wang, Shao-li; Wu, Qing-jun; Pan, Hui-peng; Li, Ru-mei; Yang, Ni-na; Liu, Bai-ming; Xu, Bao-yun; Zhou, Xiaomao; Zhang, You-jun

    2013-11-01

    The sweet potato whitefly, Bemisia tabaci (Gennadius) (Hemiptera:Aleyrodidae), is an invasive and damaging pest of field crops worldwide. The neonicotinoid insecticide imidacloprid has been widely used to control this pest. We assessed the species composition (B vs. Q), imidacloprid resistance, and association between imidacloprid resistance and the expression of five P450 genes for 14-17 B. tabaci populations in 12 provinces in China. Fifteen of 17 populations contained only B. tabaci Q, and two populations contained both B and Q. Seven of 17 populations exhibited moderate to high resistance to imidacloprid, and eight populations exhibited low resistance to imidacloprid, compared with the most susceptible field WHHB population. In a study of 14 of the populations, resistance level was correlated with the expression of the P450 genes CYP6CM1 and CYP4C64 but not with the expression of CYP6CX1, CYP6CX4, or CYP6DZ7. This study indicates that B. tabaci Q has a wider distribution in China than previously reported. Resistance to imidacloprid in field populations of B. tabaci is associated with the increased expression of two cytochrome P450 genes (CYP6CM1 and CYP4C64).

  9. Biotype status and genetic polymorphism of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) in Greece: mitochondrial DNA and microsatellites.

    Science.gov (United States)

    Tsagkarakou, A; Tsigenopoulos, C S; Gorman, K; Lagnel, J; Bedford, I D

    2007-02-01

    The genetic polymorphism and the biotype identity of the tobacco whitefly Bemisia tabaci (Gennadius) have been studied in population samples taken from different localities within Greece from cultivated plants growing in greenhouses or in open environments and from non-cultivated plants. Two different approaches were used: sequencing of the mitochondrial cytochrome oxidase I (mtCOI) gene and genotyping using microsatellite markers. Analyses of the mtCOI sequences revealed a high homogeneity between the Greek samples which clustered together with Q biotype samples that had been collected from other countries. When genetic polymorphism was examined using six microsatellite markers, the Greek samples, which were all characterized as Q biotype were significantly differentiated from each other and clustered into at least two distinct genetic populations. Moreover, based on the fixed differences revealed by the mtCOI comparison of known B. tabaci biotype sequences, two diagnostic tests for discriminating between Q and B and non-Q/non-B biotypes were developed. Implementation of these diagnostic tools allowed an absence of the B biotype and presence of the Q biotype in the Greek samples to be determined.

  10. Identification, characterization and expression of a defensin-like antifungal peptide from the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Wang, Z-Z; Shi, M; Ye, X-Q; Chen, M-Y; Chen, X-X

    2013-06-01

    Defensins are a class of small and diverse cysteine-rich proteins which have broad-spectrum antimicrobial activities. We identified and characterized a full-length cDNA encoding a putative defensin-like peptide from the whitefly Bemisia tabaci by RACE and quantitative real-time (qRT)-PCR. The full-length cDNA, named Btdef, was 388 bp long and contained an open reading frame of 228 bp. The putative mature Btdef had 46 amino acids with a molecular weight of 5.06 kDa. The deduced amino acid sequence showed significant homology with insect defensins from Heliothis virescens (76%) and Galleria mellonella (75%). The predicted mature form of Btdef was expressed as a recombinant peptide in Escherichia coli. Antimicrobial assays of the purified product indicated that Btdef was most active against fungi. qRT-PCR analyses indicated that Btdef mRNA was constitutively expressed in different tissues of B. tabaci, including fat body, midgut, ovaries and salivary gland, and was induced by fungal infection. Btdef mRNA expression was also significantly altered after feeding on different host plants, indicating that diet affects immune defences in B. tabaci. These results describe for the first time the basic properties of a defensin-like peptide from B. tabaci that probably plays an important role in the immune response against pathogens.

  11. Competitive ability and fitness differences between two introduced populations of the invasive whitefly Bemisia tabaci Q in China.

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    Yi-Wei Fang

    Full Text Available BACKGROUND: Our long-term field survey revealed that the Cardinium infection rate in Bemisia tabaci Q (also known as biotype Q population was low in Shandong, China over the past few years. We hypothesize that (1 the Cardinium-infected (C+ B. tabaci Q population cannot efficiently compete with the Cardinium-uninfected (C- B. tabaci Q population; (2 no reproductive isolation may have occurred between C+ and C-; and (3 the C- population has higher fitness than the C+ population. METHODOLOGY AND RESULTS: To reveal the differences in competitive ability and fitness between the two introduced populations (C+ and C-, competition between C+ and C- was examined over several generations. Subsequently, the reproductive isolation between C+ and C- was studied by crossing C+ with C- individuals, and the fitnesses of C+ and C- populations were compared using a two-sex life table method. Our results demonstrate that the competitive ability of the C+ whiteflies was weaker than that of C-. There is that no reproductive isolation occurred between the two populations and the C- population had higher fitness than the C+ population. CONCLUSION: The competitive ability and fitness differences of two populations may explain why C- whitefly populations have been dominant during the past few years in Shandong, China. However, the potential role Cardinium plays in whitefly should be further explored.

  12. Non-invasive delivery of dsGST is lethal to the sweet potato whitefly, Bemisia tabaci (G.) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Asokan, R; Rebijith, K B; Roopa, H K; Kumar, N K Krishna

    2015-02-01

    The sweet potato whitefly, Bemisia tabaci (G.) biotype B (Hemiptera: Aleyrodidae), is one of the most economically important pest, by being a dreaded vector of Geminiviruses, and also causes direct damage to the crops by sucking phloem sap. Glutathione S-transferase (GST) is a large family of multifunctional enzymes that play pivotal roles in the detoxification of secondary allelochemical produced by the host plants and in insecticide resistance, thus regulates insect growth and development. The objective of this study is to show the potential of RNA interference (RNAi) in the management of B. tabaci. RNAi is a sequence-specific gene silencing mechanism induced by double-stranded RNA (dsRNA) which holds tremendous potential in pest management. In this regard, we sequenced the GST from B. tabaci and synthesized approximately 500-bp dsRNA from the above and delivered through diet to B. tabaci. Real-time quantitative PCR (RT-qPCR) showed that continuous application of dsGST at 1.0, 0.5, and 0.25 μg/μl reduced mRNA expression levels for BtGST by 77.43, 64.86, and 52.95 % which resulted in mortality by 77, 59, and 40 %, respectively, after 72 h of application. Disruption of BtGST expression will enable the development of novel strategies in pest management and functional analysis of vital genes in B. tabaci.

  13. New insecticides for management of tomato yellow leaf curl, a virus vectored by the silverleaf whitefly, Bemisia tabaci.

    Science.gov (United States)

    Smith, H A; Giurcanu, M C

    2014-01-01

    Greenhouse studies using a randomized complete block design were carried out to evaluate the effect of six insecticides on transmission of Tomato yellow leaf curl virus (TYLCV) by the silverleaf whitefly, Bemisia tabaci biotype B Gennadius (Hemiptera: Aleyrodidae) to tomato, Lycopersicon esculentum (Miller) (Solanales: Solanaceae), seedlings that were inoculated with whiteflies from a TYLCV colony in cages 3, 7, or 14 d after treatment with insecticide. The purpose was to reveal differences in residual efficacy of four materials that are nearing registration for use on tomato-cyazypyr, flupyradifurone, pyrafluquinazon, and sulfoxaflor-and to compare them with two established insecticides, pymetrozine and a zeta-cypermethrin/bifenthrin combination. Differences in efficacy were expected because these six materials represent five distinct modes of action and both contact and systemic materials. Percentage of tomato seedlings expressing virus symptoms tended to be lowest in seedlings treated with flupyradifurone. The zeta-cypermethrin/bifenthrin insecticide demonstrated comparable efficacy to flupyradifurone in some trials at 3 and 7 d after treatment inoculations, but not the 14 d after treatment inoculation. Pyrafluquinazon was not statistically different from cyazypyr or sulfoxaflor in percentage of plants with virus symptoms in any trial. Percentage virus in the cyazypyr and sulfoxaflor treatments was not statistically different in the 3 and 7 d after treatment inoculations. Among seedlings treated with insecticide, percentage with virus symptoms tended to be highest in the seedlings treated with pymetrozine.

  14. Influence of cover crop and intercrop systems on Bemisia argentifolli (Hemiptera: Aleyrodidae) infestation and associated squash silverleaf disorder in zucchini.

    Science.gov (United States)

    Manandhar, Roshan; Hooks, Cerruti R R; Wright, Mark G

    2009-04-01

    Field experiments were conducted to evaluate the effects of cover cropping and intercropping on population densities of silverleaf whitefly, Bemisia argentifolli Bellow and Perring, and the incidence of squash silverleaf disorder (SSL) in zucchini, Cucurbita pepo L., in Oahu, HI. Two cover crops, buckwheat (BW), Fagopyrum esculentum Moench, and white clover (WC), Trifolium repens L., or sunn hemp (SH), Crotolaria juncea L., and an intercropped vegetable, okra, Abelmonchus esculentus L., were evaluated during the 2003, 2005, and 2006 growing seasons, respectively. Population densities of whiteflies and SSL severity varied during the three field experiments. In 2003, the severity of SSL and percentage of leaves displaying symptoms were significantly lower on zucchini plants in WC than BW plots throughout the crops' growth cycle. Additionally, the percentage of leaves per plant displaying SSL symptoms was significantly greater in bare-ground (BG) compared with the pooled BW and WC treatments on each inspection date. In 2005, zucchini intercropped with okra had lower numbers of adult whiteflies and resulted in significantly lower severity of SSL than pooled BW and WC treatments. During 2006, zucchini grown with SH had significantly lower numbers of all whitefly stages (i.e., egg, immature, and adult) and less SSL severity symptoms than BW. Despite these differences in whitefly numbers and SSL severity, marketable yields were not significantly lower in BW compared with WC or SH treatment plots during the study. The mechanisms underlying these results and the feasibility of using cover crops and intercrops to manage B. argentifolli and SSL are discussed.

  15. Inoculation of tomato plants with rhizobacteria enhances the performance of the phloem-feeding insect Bemisia tabaci

    Directory of Open Access Journals (Sweden)

    Roee eShavit

    2013-08-01

    Full Text Available In their natural environment, plants experience multiple biotic interactions and respond to this complexity in an integrated manner. Therefore, plant responses to herbivory are flexible and depend on the context and complexity in which they occur. For example, plant growth promoting rizhobacteria (PGPR can enhance plant growth and induce resistance against microbial pathogens and herbivorous insects by a phenomenon termed induced systemic resistance (ISR. In the present study, we investigated the effect of tomato (Solanum lycopersicum pre-inoculation with the PGPR Pseudomonas fluorescens WCS417r, on the performance of the generalist phloem-feeding insect Bemisia tabaci. Based on the ability of P. fluorescens WCS417r to prime for ISR against generalists chewing insects and necrotrophic pathogens, we hypothesized that pre-inoculated plants will strongly resist B. tabaci infestation. In contrast, we discovered that the pre-inoculation treatment increased the tomato plant suitability for B. tabaci which was emphasized both by faster developmental rate and higher survivability of nymph stages on pre-inoculated plants. Our molecular and chemical analyses suggested that the phenomenon is likely to be related to: (I the ability of the bacteria to reduce the activity of the plant induced defense systems; (II a possible manipulation by P. fluorescens of the plant quality (in terms of suitability for B. tabaci through an indirect effect on the rhizosphere bacterial community. The contribution of our study to the pattern proposed for other belowground rhizobacteria and mycorrhizal fungi and aboveground generalist phloem-feeders is discussed.

  16. Single basal application of thiacloprid for the integrated management of Meloidogyne incognita and Bemisia tabaci in tomato crops

    Science.gov (United States)

    Dong, Sa; Ren, Xiaofen; Zhang, Dianli; Ji, Xiaoxue; Wang, Kaiyun; Qiao, Kang

    2017-01-01

    Tomato growers commonly face heavy nematode (Meloidogyne incognita) and whitefly (B-biotype Bemisia tabaci) infestations, and previous studies demonstrated that thiacloprid could be used to control M. incognita and B. tabaci in cucumber. However, the efficacy of a single basal application of thiacloprid to control both pests and its effect on yield in tomato remains unknown. In this study, the potential of thiacloprid application to the soil for the integrated control of M. incognita and B. tabaci in tomato was evaluated in the laboratory and the field. Laboratory tests showed that thiacloprid was highly toxic to whitefly adults and eggs with an average lethal concentration 50 (LC50) of 14.7 and 62.2 mg ai L‑1, respectively, and the LC50 of thiacloprid for nematode J2s and eggs averaged 36.2 and 70.4 mg ai L‑1, respectively. In field trials, when thiacloprid was applied to the soil at 7.5, 15 and 30 kg ha‑1 in two consecutive years, whitefly adults decreased by 37.8–75.4% within 60 days of treatment, and the root-galling index was reduced by 31.8–85.2%. Optimum tomato plant growth and maximum yields were observed in the 15 kg ha‑1 treatment. The results indicated that a single basal application of thiacloprid could control M. incognita and B. tabaci and enhance tomato growth and yield.

  17. Mulheres negras e brancas e os níveis de acesso aos serviços preventivos de saúde: uma análise sobre as desigualdades

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    Emanuelle Freitas Goes

    Full Text Available O racismo institucional é um fator determinante no acesso aos serviços de saúde, principalmente para as mulheres negras que sofrem com o impacto das intersecções das desigualdades de gênero e raça. O objetivo deste estudo é determinar os diferenciais das características sócio demográficas e os níveis de acesso aos serviços preventivos de mulheres na Bahia, segundo raça/cor. Os resultados revelam que, para o nível de acesso considerado bom, as mulheres brancas representam 15,4%, enquanto as negras respondem por 7,9%. O estudo demonstrou que as desigualdades raciais e o racismo institucional são uma barreira no acesso aos serviços preventivos de saúde para as mulheres negras.

  18. A “Volta do Real” e as formas do realismo no cinema contemporâneo: o trauma em Caché e A Fita Branca; o abjeto em Anticristo; o banal em Mutum

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    Marília Xavier Lima

    2010-12-01

    Full Text Available Esta pesquisa busca compreender o resgate do realismo no cinema contemporâneo, tomando como ponto chave a evocação do real feita de duas maneiras: uma, através do trauma elucidado por Hal Foster com base nas artes visuais e a outra por meio do “sublime do banal” exposto por Denilson Lopes. Para tal, foram discutidos os filmes Caché e A Fita Branca, do diretor Michael Haneke para explicitar o real no trauma; o Anticristo de Lars Von Trier para o caso do real no abjeto; e, por fim, no cenário brasileiro, o filme Mutum de Sandra Kogut no que tange ao “sublime do banal”. Procurando, dessa forma, compreender os elementos estéticos do realismo cinematográfico contemporâneo.

  19. Similaridades e diferenças indicativas de identidade e evolução cultural no estilo Serra Branca de pinturas rupestres do Parque Nacional Serra da Capivara, Piauí - Brasil

    OpenAIRE

    2007-01-01

    A presente dissertação refere-se a pinturas rupestres da Tradição Nordeste da área do Parque Nacional Serra da Capivara, no Piauí. A pesquisa objetivou fazer uma particularização na apresentação gráfica dos registros do estilo Serra Branca, por meio de suas similaridades e diferenças, presentes em 21 sítios arqueológicos distribuídos geograficamente em diversos pontos da área do Parque Nacional e entorno. Para tal, fez-se um levantamento do material catalográfico existente no a...

  20. Interacções mãe-bebé em díades de raça branca e díades de raça negra

    OpenAIRE

    Oliveira, Dora Santos

    2008-01-01

    Dissertação de Mestrado apresentada ao ISPA - Instituto Universitário O objectivo do presente estudo foi comparar os padrões de interacção mãe-bebé em díades de raça branca e díades de raça negra. Para além disso, procurou-se reflectir sobre seis pares mãe-bebé, tendo por base o modelo psicodinâmico. O método utilizado foi o Estudo de Caso e os instrumentos utilizados foram o “Método de Observação de Bebés de Esther Bick” (1963) e a “Entrevista R” de Stern (1989). Foi analisada...

  1. Interacções mãe-bebé em díades de raça branca e díades de raça negra

    OpenAIRE

    Oliveira, Dora Santos

    2008-01-01

    Dissertação de Mestrado apresentada ao ISPA - Instituto Universitário O objectivo do presente estudo foi comparar os padrões de interacção mãe-bebé em díades de raça branca e díades de raça negra. Para além disso, procurou-se reflectir sobre seis pares mãe-bebé, tendo por base o modelo psicodinâmico. O método utilizado foi o Estudo de Caso e os instrumentos utilizados foram o “Método de Observação de Bebés de Esther Bick” (1963) e a “Entrevista R” de Stern (1989). Foi analisada...

  2. Influence of aging on the quality of the skin of white women: the role of collagen Influência do envelhecimento na qualidade da pele de mulheres brancas: o papel do colágeno

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    Eloina do Rocio Valenga Baroni

    2012-10-01

    Full Text Available PURPOSE: Evaluate the influence of aging on the quality of the skin of white women, analyzing the dermal collagen. METHODS: Pre-auricular flaps were collected for histological and morphometric analysis of 218 white women who underwent spontaneous facial aesthetic plastic surgery. Picrosirius ultrared stain was used for analysis and quantification of collagen in five age groups (OBJETIVO: Avaliar a influência do envelhecimento na qualidade da pele de mulheres brancas analisando o colágeno dérmico. MÉTODOS: Realizou-se análise histológica e morfométrica de 218 retalhos pré-auriculares de mulheres brancas que se submeteram espontaneamente à cirurgia estética facial. Foi usada a coloração de Picrosirius Ultrared para analisar e quantificar os colágenos I, III e total em cinco grupos etários (<40 anos, 40 a 49 anos, 50 a 59 anos, 60 a 69 anos e 70 a 79 anos. RESULTADOS: A análise histológica mostrou alterações sugestivas de envelhecimento cutâneo (fragmentação e desorganização das fibras de colágeno, especialmente em pacientes acima de 60 anos. Não houve diferenças significantes entre a idade e a espessura da derme e da epiderme, mas houve diferenças significantes entre as percentagens de colágeno I, III e total (p<0,001 com o aumento da idade. CONCLUSÃO: Existe redução do colágeno com o aumento da idade e um aumento na sua degradação, levando à fragmentação das fibras.

  3. Ciclo biológico, exigências térmicas e parasitismo de Muscidifurax uniraptor em pupas de mosca doméstica Life cycle, thermal requirements and parasitism of Muscidifurax uniraptor on house fly pupae

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    Marcílio José Thomazini

    2001-09-01

    Full Text Available Os parasitóides pupais estão entre os principais responsáveis pela redução populacional de mosca doméstica em aviários, e Muscidifurax uniraptor Kogan & Legner (Hymenoptera: Pteromalidae é um dos principais parasitóides presentes nestes ambientes no Estado de São Paulo. O objetivo deste trabalho foi determinar a duração do ciclo biológico, as exigências térmicas e o parasitismo de M. uniraptor em pupas de Musca domestica L. (Diptera: Muscidae em temperaturas constantes. Os testes foram realizados em câmaras climatizadas nas temperaturas de 18, 20, 22, 25, 28, 30 e 32 ± 1°C, 70 ± 10% U.R. e 14 h de fotofase. Em cada câmara 200 pupas de mosca doméstica, com 24 a 48 h de idade, foram expostas a 40 parasitóides fêmeas partenogenéticas, com 0 a 24 h de idade, por 24 h. A temperatura influenciou o desenvolvimento e a reprodução de M. uniraptor. O menor valor do período de ovo a adulto foi a 30°C (17 dias e as porcentagens de parasitismo e de emergência de descendentes foram maiores a 28°C, com 87 e 63,5%, respectivamente. A temperatura base encontrada para fêmeas do parasitóide foi de 9,43°C, com uma constante térmica de 366,62 graus-dia (GD. A elevação da temperatura diminui a duração do período de ovo a adulto (entre 18 e 30°C e aumenta o parasitismo (entre 18 e 28°C de M. uniraptor. A faixa de temperatura entre 28 e 30°C é considerada a mais adequada para criação de M. uniraptor em pupas de mosca doméstica.The pupal parasitoids are among the most important organisms responsible for house fly population reduction in poultry farms. Muscidifurax uniraptor Kogan & Legner (Hymenoptera: Pteromalidae is one of the main parasitoids that occur in poultry farms at São Paulo State, Brazil. The objective of this study was to determine the life cycle duration, the thermal requirements and the parasitism of M. uniraptor on Musca domestica L. (Diptera: Muscidae pupae under constant temperatures. The experiment was

  4. Caracterización de Daños de Moscas del Género Dasiops (Diptera: Lonchaeidae en Passiflora spp. (Passifloraceae Cultivadas en Colombia / Characterization of Damage of the Genus Dasiops Flies (Diptera: Lonchaeidae from Cultivated Passiflora (Passiflor

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    Maikol Yohanny Santamaría Galindo

    2014-03-01

    Full Text Available Resumen. Las moscas del género Dasiops Rondani constituyen la plaga más limitante en cultivos de pasifloras en Colombia, por lo que el reconocimiento de especies es importante para la toma de decisiones de vigilancia y control. Se caracterizaron los síntomas y daños producidos por moscas Dasiops spp.. en botones florales y frutos de maracuyá (Passiflora edulis f. flavicarpa Sims, gulupa (Passiflora edulis f. edulis Sims, granadilla (Passiflora ligularis Juss y curuba (Passiflora tripartita var. mollissima Nielsen y Jorgensen. En botones florales de maracuyá, gulupa y granadilla con longitud mayor a 1 cm, la infestación se manifestó con amarillamiento y arrugamiento general. En frutos de gulupa y granadilla, la infestación se evidenció por arrugamiento del epicarpio en frutos inmaduros. En curuba, la infestación en frutos se caracterizó por un estrechamiento en la parte basal, apical o media del fruto. La infestación en botones florales estuvo entre 0,0 y 9,9% en tanto que en frutos presentó un rango entre 0,3 y 28,5%. No obstante, en maracuyá y gulupa se registraron botones florales infestados pero sin los síntomas descritos; en tanto que en gulupa y granadilla se observó el mismo fenómeno en frutos. Este estudio provee a agricultores y técnicos herramientas para el reconocimiento de infestación por moscas Dasiops spp. en cultivos de pasifloras como elemento fundamental para la toma decisiones para la vigilancia y control fitosanitario. / Abstract. The flies of the gender Dasiops Rondani are the most limiting plague in pasifloras crops in Colombia, thus species identification is important for decision making for monitoring and control. The symptoms and damage caused by Dasiops spp. flies in flower buds and fruits of yellow passion fruit (Passiflora edulis f. flavicarpa Sims, purple passion fruit (Passiflora edulis f. edulis Sims, sweet passion fruit (Passiflora ligularis Juss and banana passion fruit (Passiflora tripartita

  5. Ação de fungos entomopatogênicos em larvas e adultos da mosca do figo Zaprionus indianus (Diptera: Drosophilidae Action of entomopathogenic fungi on the larvae and adults of the fig fly Zaprionus indianus (Diptera: Drosophilidae

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    Virgínia Michelle Svedese

    2012-11-01

    Full Text Available A mosca do figo, Zaprionus indianus, vem se disseminando no Brasil e causou nos últimos anos perdas de até 50% na produção de figos. Uma alternativa viável de controle desta mosca pode ser a utilização de fungos entomopatogênicos. Este trabalho foi conduzido em laboratório (27±1°C, UR 70±10% e fotoperíodo de 12h para avaliar a suscetibilidade dos estágios de larva e adulto de Z. indianus a cinco concentrações (10(8 a 10(4 conídios mL-1 de B. bassiana (URM2915; ESALQ447 e M. anisopliae (URM3349; URM4403. Não houve mortalidade larval e o período de pré-pupa não sofreu alteração em relação ao grupo controle, já o estágio de pupa foi aumentado em até três dias quando se utilizou B. bassiana. A emergência de adultos diminuiu em relação ao grupo controle: 10,6% quando as larvas foram tratadas com a maior concentração de B. bassiana URM2916 e 2,0% com M. anisopliae URM4403. No bioensaio com adultos, a mortalidade máxima atingiu 98,7% com B. bassiana e 100,0% com M. anisopliae. Os menores valores da CL50 foram de 1,09x10(5 conídios mL-1 para B. bassiana URM2916 e de 1,94x10(4 conídios mL-1 para M. anisopliae URM4403. O tempo letal médio (TL50 variou de 4,5 a 6,12 dias. Os resultados demonstraram que ambos os fungos são eficientes e mostram ser promissores agentes biocontroladores da mosca do figo, com destaque para M. anisopliae URM4403.The "fig fly", Zaprionus indianus, has spread by in Brazil and in recent years and has caused losses of up to 50% in the production of figs. A viable alternative to control this fly may be the use of entomopathogenic fungi such. The present study was developed in laboratory (27±1°C, RH 70±10% and 12h photoperiod, to assess the susceptibility of larval and adult stages of Z. indianus to five concentrations (10(8 to 10(4 conidia mL-1 of B. bassiana (URM2915; ESALQ447 and M. anisopliae (URM3349; URM4403. There was no larval mortality and the pre-pupal period did not change compared

  6. Effect of Iranian Bt cotton on life table of Bemisia tabaci (Hemiptera: Alyrodidae) and Cry 1Ab detection in the whitefly honeydew

    OpenAIRE

    2016-01-01

    Transgenic cotton expressing the Cry 1Ab protein of Bacillus thuringiensis developing against Helocoverpa armigera may be affect on secondary pest such as Bemisia tabaci. In this study effects of Bt cotton on demographic parameters of B. tabaci were assessed and the data analyzed using the age specific, two-sex life table parameters. Results showed that getting to the adulthood stage, was faster on non-Bt cotton in comparison with Bt cotton. Also the fecundity was higher on non-Bt cotton than...

  7. Diversidade de moscas-das-frutas em pomares de citros no município de Araruama, RJ Diversity of fruit flies in citrus groves in the municipality of Araruama, RJ

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    Jorge Ferreira de Souza

    2008-04-01

    Full Text Available O objetivo deste estudo foi determinar as espécies de Tephritidae e Lonchaeidae (Diptera: Tephritoidea de ocorrência em pomares de laranja doce (Citrus sinensis Osbeck e tangerina (Citrus reticulata Blanco, no município de Araruama, RJ, durante o período de dezembro de 2002 a novembro de 2003. Os espécimes foram coletados em armadilhas McPhail contendo solução aquosa de proteína hidrolisada a 5% e em amostras de frutos de seis variedades de citros. Nas armadilhas, o total de 2.543 adultos de Tephritoidea (1.430 fêmeas e 1.023 machos foi capturado, sendo dez espécies de Tephritidae, quatro espécies e dois morfotipos de Lonchaeidae. Dos Tephritidae e capturados nas McPhail, quatro espécies (Anastrepha fraterculus, A. obliqua, A. sororcula e Ceratitis capitata infestaram frutos cítricos, enquanto que, dos Lonchaeidae, somente os morfotipos não infestaram as amostras de citros. Os resultados demonstram que a densidade populacional das moscas-das-frutas pode ser superestimada, quando baseada no número de moscas por armadilha, devido à captura de espécies que não infestam os frutos de interesse comercial.This study was aimed at determining the species of Tephritidae and Lonchaeidae (Diptera: Tephritoidea that occur on groves of sweet orange (Citrus sinensis Osbeck and tangerine (Citrus reticulata Blanco in the municipality of Araruama, state of Rio de Janeiro, Brazil, from December, 2002 to November, 2003. The specimens were collected by McPhail traps with aqueous solution of hydrolyzed protein to 5% and in fruits samples of six varieties of citrus. In the traps the total of 2,543 adults of Tephritoidea (1,430 females and 1,023 males was captured, being ten species of Tephritidae, four species and two morphotypes of Lonchaeidae. From the Tephritidae caught by the McPhail, four species (Anastrepha fraterculus, A. obliqua, A. sororcula and Ceratitis capitata infested citric fruits while the Lonchaeidae, the morphotypes did not infest

  8. Fatores associados à baixa densidade mineral óssea em mulheres brancas Factors associated with low bone mineral density among white women

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    Paulo Frazão

    2007-10-01

    Full Text Available OBJETIVO: Analisar se os fatores para baixa densidade mineral óssea em mulheres idosas são os mesmos observados em outras faixas etárias. MÉTODOS: Realizou-se estudo transversal em amostra aleatória de prontuários de 413 mulheres brancas assistidas em serviço de diagnóstico por imagem, na cidade de Santos, estado de São Paulo, em 2003. Foram considerados os valores de densidade mineral óssea femoral ajustada pelo T-score. Foram investigadas as variáveis: idade, índice de massa corporal, tabagismo, consumo de álcool e leite, atividade física e terapia de reposição hormonal. Empregou-se regressão logística não condicional uni e multivariada. RESULTADOS: Na amostra, 52,5% tinham até 59 anos e 47,5% tinham 60 anos ou mais. O valor médio da densidade mineral óssea foi 0,867 g/cm² (dp=0,151 para o colo do fêmur. Valores significativos, ajustados pela idade foram obtidos para atividade física (OR ajustada=0,47; IC 95%: 0,23;0,97, índice de massa corporal igual ou superior a 30,0 kg/m² (OR ajustada=0,10; IC 95%: 0,05;0,21, etilismo (OR ajustada=7,90; IC 95%: 2,17;28,75, pouco consumo de leite (OR ajustada=3,29; IC 95%: 1,91;5,68 e reposição hormonal (OR ajustada=0,44; IC 95%: 0,21;0,90. Em mulheres idosas, massa corporal, consumo de leite e atividade física foram fatores de proteção independentes. CONCLUSÕES: Idade avançada, massa corporal, atividade física, consumo de leite e álcool foram importantes fatores na regulação da massa óssea. A influência de fatores comportamentais se manteve nas mulheres em idade avançada, reforçando o papel das medidas preventivas na prática médica e das políticas de promoção de saúde voltadas ao envelhecimento saudável.OBJECTIVE: To analyze whether the factors causing low bone mineral density among elderly women are the same as those observed in other age groups. METHODS: A cross-sectional study was carried out on the medical records of a random sample of 413 white women

  9. Efficiency of neem oil nanoformulations to Bemisia tabaci (GENN. Biotype B (Hemiptera: AleyrodidaeEficiência de nanoformulações a base de óleo de nim sobre Bemisia tabaci (GENN. Biótipo B (Hemiptera: Aleyrodidae

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    Sheila Salles Carvalho

    2012-04-01

    Full Text Available The nanotechnology, through encapsulation of active ingredients, has showed an important way to avoid problems with quickly degradation of the pesticide molecules. Thus, neem (Azadirachta indica oil nanoformulations containing ?-ciclodextrin and poli-?-caprolactone (PCL were tested as to their control efficiency against eggs and nymphs of Bemisia tabaci (Genn. biotype B reared in soybean. The Lethal Concentration (LC50 was estimated using a commercial neem oil (Organic Neem® on first-instar nymphs to establish the adequate volume of the nanoformulations per treatment. After that, they were sprayed on eggs and first-instar nymphs in laboratory and greenhouse and on third-instar nymphs in greenhouse. The commercial neem oil and distilled water were used as controls. Egg viability was not affected by any treatment. Among six nanoformulations, only one was efficient against the first-instar nymphs in laboratory conditions. However, its effective period was not increased as expected. In greenhouse, first-instar nymphs were more affected by two nanoformulations which were significantly different of the commercial neem oil - the most effective one. No mortality differences among the formulations in the third-instar test were observed. The nanoformulations were less efficient to control the B. tabaci biotype B nymphs than the commercial neem oil. A nanotecnologia, através do encapsulamento de ingredientes ativos, tem-se revelado uma importante estratégia para evitar problemas com a rápida degradação de moléculas inseticidas. Assim, nanoformulações à base de óleo de nim (Azadirachta indica utilizando os polímeros ?-ciclodextrina e poli-?-caprolactona (PCL foram testadas quanto a sua eficiência de controle de ovos e ninfas de Bemisia tabaci (Genn. biótipo B mantidas em soja. Foi estimada a CL50 utilizando uma formulação comecial de óleo de nim (Organic Neem® sobre ninfas em 1º ínstar da qual se estipulou o volume das nanoformula

  10. Evaluación de ácido acético como fumigante de mosquita blanca Bemisia tabaci (Gennadious en laboratorio y campo Assessment of acetic acid like fumigant of silverleaf whitefly Bemisia tabaci (Gennadious in laboratory and field

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    José Alfredo Samaniego Gaxiola

    2012-06-01

    Full Text Available El objetivo de este trabajo fue evaluar la capacidad del ácido acético (AA como fumigante en contra de Bemisia tabaci (moquita blanca que es un plaga de importancia nacional. En el laboratorio, se fumigó el insecto con tres regímenes de dosis - tiempo: (ambos medios, baja - largos y altas - cortos. En el campo, las hojas de calabaza de cuatro variedades fueron fumigadas con 8, 16 y 32 µg ml-1 de AA en tiempos de 20, 40 y 60 min; adicionalmente, se evaluó el daño en las hojas (fitotoxicidad después de fumigarse. En el laboratorio, tiempo de fumigación > 15 miny 8 µg ml-1 de AA mató 100% de la mosquita, mientras que, su supervivencia se redujo 40% al fumigarla ocho horas con 2 µg ml-1de AA; pero la incubación del testigo (mosquita sin fumigar por ≥ 16 h también redujo su supervivencia; entretanto, con 8 y 16 µml-¹ de AA se redujo la supervivencia del insecto desde los cinco minutos (~20-80%. En el campo, la mosquita sobrevivió ~ 40% en las hojas de las cuatro variedades después de fumigarse con AA(8-32 µgml-¹ durante 20 min, pero el insecto prácticamente no sobrevivió al aumentar el tiempo de fumigación a 60 min. Las hojas mostraron un daño severo (fitotoxicidad > al 50% excepto en la dosis de 8 µg ml-¹ a los 20 min con un daño de ~ 20%. Se discuten alternativas del empleo del AA como fumigante.The aim of this work was to assess the capacity of acetic acid (AA like fumigant against Bemisia tabaci (silverleaf whitefly which is a pest of national importance. In laboratory, the bug was fumigated with three doses-time regimes: (both media, low dose-long time and high dose-short time. In field, squash leaves of four varieties were fumigated with 8, 16 and 32 µg ml-¹ of AA during of 20, 40 and 60 min; additionally, it was assessed damage in foils (phytotoxicity after fumigation. In laboratory, fumigation time > 15 min and 8µgml-¹ of AA killed 100% of whitefly, while its survival was reduced 40% when fumigated eight hours

  11. Toxicity of neem oil to Bemisia tabaci biotype B nymphs reared on dry bean Toxicidade de óleo de nim para ninfas de Bemisia tabaci biótipo B criadas em feijoeiro

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    Patricia Valle Pinheiro

    2009-04-01

    Full Text Available The objective of this work was to determine the most susceptible nymphal stage of Bemisia tabaci biotype B to neem (Azadirachta indica A. Juss. oil applied to dry bean (Phaseolus vulgaris L. in a screenhouse. A solution of commercial oil (Dalneem extracted from neem seeds was sprayed directly on each nymphal instar at 0, 0.1, 0.25, 0.5, 1 and 2% concentrations for lethal concentration (LC determination, and at 0, 0.5 and 1% concentrations for lethal time (LT determination. The number of living and dead nymphs was recorded five days after spraying for LC determination, and daily during six days for LT determination. The LC50 estimated for fourth instar nymphs occurred at 0.56% concentration. For all instars, LC50 and LC95 were estimated at 0.32 and 2.78% concentrations, respectively. The estimated values of LT50 at 1% concentration were 2.46, 4.45, 3.02 and 6.98 days for the first to fourth instars, respectively. The LT50 occurred at five days for 0.5% and at four days for 1% concentration in all instars. A mortality rate of over 80% was observed on the 6th day for the first to third instars at 1% concentration. The first three nymphal stages were more susceptible to neem oil when compared to the fourth nymphal stage.O objetivo deste trabalho foi determinar o estágio ninfal de Bemisia tabaci biótipo B mais suscetível ao óleo de nim (Azadirachta indica A. Juss. aplicado em feijoeiro (Phaseolus vulgaris L., em casa telada. Foram avaliados o tempo letal (TL e concentração letal (CL do óleo comercial de sementes de nim Dalneem. Para CL, concentrações de 0, 0,1, 0,25, 0,5, 1 e 2% do produto foram pulverizadas diretamente sobre as ninfas em cada ínstar. Para TL, o produto foi avaliado a 0, 0,5 e 1% de óleo de nim em cada ínstar. Ninfas vivas e mortas foram contadas cinco dias após a pulverização para CL e diariamente para TL durante seis dias. Para o quarto ínstar, a CL50 foi de 0,56% de óleo de nim. Considerando todos os ínstares, CL

  12. Tomato yellow vein streak virus: relationship with Bemisia tabaci biotype B and host range Tomato yellow vein streak virus: interação com a Bemisia tabaci biótipo B e gama de hospedeiros

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    Ana Carolina Firmino

    2009-12-01

    Full Text Available The Tomato yellow vein streak virus (ToYVSV is a putative species of begomovirus, which was prevalent on tomato crops in São Paulo State, Brazil, until 2005. The objectives of this study were to evaluate the interaction between ToYVSV and its vector Bemisia tabaci biotype B and to identify alternative hosts for the virus. The minimum acquisition and inoculation access periods of ToYVSV by B. tabaci were 30 min and 10 min, respectively. Seventy five percent of tomato-test plants were infected when the acquisition and inoculation access periods were 24 h. The latent period of the virus in the insect was 16 h. The ToYVSV was retained by B. tabaci until 20 days after acquisition. First generation of adult whiteflies obtained from viruliferous females were virus free as shown by PCR analysis and did not transmit the virus to tomato plants. Out of 34 species of test-plants inoculated with ToYVSV only Capsicum annuum, Chenopodium amaranticolor, C. quinoa, Datura stramonium, Gomphrena globosa, Nicotiana clevelandii and N. tabacum cv. TNN were susceptible to infection. B. tabaci biotype B was able to acquire the virus from all these susceptible species, transmitting it to tomato plants.O Tomato yellow vein streak virus (ToYVSV é uma espécie putativa de begomovirus que infecta o tomateiro (Solanum lycopersicon em diversas regiões do Brasil onde se cultiva essa solanácea, sendo a espécie prevalente no estado de São Paulo até 2005. Estudou-se a interação do ToYVSV com a Bemisia tabaci biótipo B e identificaram-se hospedeiras alternativas deste vírus. Os períodos de acesso mínimo de aquisição (PAA e de inoculação (PAI foram de 30 min e 10 min, respectivamente. A porcentagem de plantas infectadas chegou até cerca de 75% após um PAA e PAI de 24 h. O período de latência do vírus no vetor foi de 16 horas. O ToYVSV foi retido pela B. tabaci até 20 dias após a aquisição do vírus. Não foi detectada transmissão do vírus para prog

  13. Assessment of Potential Sublethal Effects of Various Insecticides on Key Biological Traits of The Tobacco Whitefly, Bemisia tabaci

    Science.gov (United States)

    He, Yuxian; Zhao, Jianwei; Zheng, Yu; Weng, Qiyong; Biondi, Antonio; Desneux, Nicolas; Wu, Kongming

    2013-01-01

    The tobacco whitefly Bemisia tabaci is one of the most devastating pests worldwide. Current management of B. tabaci relies upon the frequent applications of insecticides. In addition to direct mortality by typical acute toxicity (lethal effect), insecticides may also impair various key biological traits of the exposed insects through physiological and behavioral sublethal effects. Identifying and characterizing such effects could be crucial for understanding the global effects of insecticides on the pest and therefore for optimizing its management in the crops. We assessed the effects of sublethal and low-lethal concentrations of four widely used insecticides on the fecundity, honeydew excretion and feeding behavior of B. tabaci adults. The probing activity of the whiteflies feeding on treated cotton seedlings was recorded by an Electrical Penetration Graph (EPG). The results showed that imidacloprid and bifenthrin caused a reduction in phloem feeding even at sublethal concentrations. In addition, the honeydew excretions and fecundity levels of adults feeding on leaf discs treated with these concentrations were significantly lower than the untreated ones. While, sublethal concentrations of chlorpyrifos and carbosulfan did not affect feeding behavior, honeydew excretion and fecundity of the whitefly. We demonstrated an antifeedant effect of the imidacloprid and bifenthrin on B. tabaci, whereas behavioral changes in adults feeding on leaves treated with chlorpyrifos and carbosulfan were more likely caused by the direct effects of the insecticides on the insects' nervous system itself. Our results show that aside from the lethal effect, the sublethal concentration of imidacloprid and bifenthrin impairs the phloem feeding, i.e. the most important feeding trait in a plant protection perspective. Indeed, this antifeedant property would give these insecticides potential to control insect pests indirectly. Therefore, the behavioral effects of sublethal concentrations of

  14. Tomato pathogenesis-related protein genes are expressed in response to Trialeurodes vaporariorum and Bemisia tabaci biotype B feeding.

    Science.gov (United States)

    Puthoff, David P; Holzer, Frances M; Perring, Thomas M; Walling, Linda L

    2010-11-01

    The temporal and spatial expression of tomato wound- and defense-response genes to Bemisia tabaci biotype B (the silverleaf whitefly) and Trialeurodes vaporariorum (the greenhouse whitefly) feeding were characterized. Both species of whiteflies evoked similar changes in tomato gene expression. The levels of RNAs for the methyl jasmonic acid (MeJA)- or ethylene-regulated genes that encode the basic β-1,3-glucanase (GluB), basic chitinase (Chi9), and Pathogenesis-related protein-1 (PR-1) were monitored. GluB and Chi9 RNAs were abundant in infested leaves from the time nymphs initiated feeding (day 5). In addition, GluB RNAs accumulated in apical non-infested leaves. PR-1 RNAs also accumulated after whitefly feeding. In contrast, the ethylene- and salicylic acid (SA)-regulated Chi3 and PR-4 genes had RNAs that accumulated at low levels and GluAC RNAs that were undetectable in whitefly-infested tomato leaves. The changes in Phenylalanine ammonia lyase5 (PAL5) were variable; in some, but not all infestations, PAL5 RNAs increased in response to whitefly feeding. PAL5 RNA levels increased in response to MeJA, ethylene, and abscisic acid, and declined in response to SA. Transcripts from the wound-response genes, leucine aminopeptidase (LapA1) and proteinase inhibitor 2 (pin2), were not detected following whitefly feeding. Furthermore, whitefly infestation of transgenic LapA1:GUS tomato plants showed that whitefly feeding did not activate the LapA1 promoter, although crushing of the leaf lamina increased GUS activity up to 40 fold. These studies indicate that tomato plants perceive B. tabaci and T. vaporariorum in a manner similar to baterical pathogens and distinct from tissue-damaging insects.

  15. Host plant effects on alkaline phosphatase activity in the whiteflies, Bemisia tabaci Biotype B and Trialeurodes vaporariorum.

    Science.gov (United States)

    Yan, Ying; Peng, Lu; Liu, Wan-Xue; Wan, Fang-Hao; Harris, Marvin K

    2011-01-01

    Bemisia tabaci (Gennadius) B-biotype and Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) often coexist on greenhouse-grown vegetable crops in northern China. The recent spread of B. tabaci B-biotype has largely replaced T. vaporariorum, and B-biotype now overlaps with T. vaporariorum where common hosts occur in most invaded areas. The impact of the B-biotype on the agro eco system appears to be widespread, and involves the ability to compete with and perhaps replace other phytophages like T. vaporariorum. An emerging hypothesis is that the B-biotype is physiologically superior due at least in part to an improved ability to metabolically utilize the alkaline phosphatase pathway. To test this hypothesis, alkaline phosphatase activity was studied in the B-biotype and T. vaporariorum after feeding on a number of different hosts for a range of durations, with and without host switching. Alkaline phosphatase activity in T. vaporariorum was 1.45 to 2.53-fold higher than that of the B-biotype when fed on tomato for 4 and 24 h, or switched from tomato to cotton and cabbage for the same durations. However, alkaline phosphatase activity in the B-biotype was 1.40 to 3.35-fold higher than that of T. vaporariorum when the host switching time was ∼72 and ∼120 h on the same plant. Both short-term (4 h) and long-term (72 h) switching of plant hosts can significantly affect the alkaline phosphatase activity in the two species. After ∼120 h, feeding on tomato and cotton alkaline phosphatase activity in the B-biotype was significantly higher than that of T. vaporariorum. It was shown that alkaline phosphatase aids the species feeding on different plant species, and that the B-biotype is physiologically superior to T. vaporariorum in utilizing the enzyme compared to T. vaporariorum over longer periods of feeding.

  16. Effects of host plants on insecticide susceptibility and carboxylesterase activity in Bemisia tabaci biotype B and greenhouse whitefly, Trialeurodes vaporariorum.

    Science.gov (United States)

    Liang, Pei; Cui, Jian-Zhou; Yang, Xiu-Qing; Gao, Xi-Wu

    2007-04-01

    Bemisia tabaci (Gennadius) biotype B and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood), have become serious pests of cotton and vegetable crops in China since the early 1990s. In recent years, however, B. tabaci have broken out more frequently and widely than have T. vaporariorum. The B. tabaci biotype B has also developed higher resistance to several insecticides. Here, the effects of four different host plants on the insecticide susceptibility of B. tabaci biotype B and T. vaporariorum have been compared. The LC(50) values of imidacloprid, abamectin, deltamethrin and omethoate in T. vaporariorum reared on cucumber were significantly higher than those in B. tabaci (the LC(50) values in T. vaporariorum were respectively 3.13, 2.63, 2.78 and 6.67 times higher than those in B. tabaci). On the other hand, the B. tabaci population reared on cotton was more tolerant to all four insecticides tested than the T. vaporariorum population from the same host, especially to abamectin (up to 8.4-fold). The effects of the four host plants on the activity of carboxylesterase (CarE) in B. tabaci biotype B and T. vaporariorum were also compared. The results showed that, although the CarE activity of B. tabaci and T. vaporariorum varied depending on the host plants, the B. tabaci population possessed significantly higher CarE activity than the T. vaporariorum population reared on the same host plant. This was especially so on cucumber and cotton, where the CarE activities of the B. tabaci population were over 1.6 times higher than those of T. varporariorum. The frequency profiles for this activity in B. tabaci and T. vaporariorum populations reared on same host plant were apparently different.

  17. Chitinolytic Bacteria Isolated from Chili Rhizosphere: Chitinase Characterization and Its Application as Biocontrol for Whitefly (Bemisia tabaci Genn.

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    Nisa R. Mubarik

    2010-01-01

    Full Text Available Problem statement: Chitin, a common constituent of insect exoskeleton, could be hydrolyzed by chitinase. The research was conducted to screen chitinolytic rhizobacteria isolated from rhizosphere of chilli pepper and to determine their chitinase activity in degrading chitin of whitefly, Bemisia tabaci Genn. (Hemiptera: Aleyrodidae. Whitefly is recognized as an important pest on many crops including chilli pepper. Approach: Screening and molecular identification based on 16S rRNA sequence of chitinolytic isolates, chitinase productions, measurement of chitinase activity, characterization of chitinase and effect of the chitinase treatment on whitefly were studied. Results: A total of 25 isolates of rhizobacteria formed a clear zone on solid chitin media. Two isolates, i.e., I.5 and I.21 isolates had the highest chitinolytic index. Based on sequence of 16S rRNA gene, the isolates of I.5 and I.21 were identified as Bacillus sp. and Bacillus cereus, respectively. The highest chitinolytic index and specific activity of I.5 isolate was 0.94 and 0.11 U mg-1 proteins, respectively. Maximum production of I.5 chitinase was occured after 36 h cultivation at 30°C and pH 7.0. The highest chitinolytic index and specific activity of I.21isolate was 0.75 and 0.114 U mg-1 proteins, respectively. Maximum production of I.21 chitinase was occured after 36 h cultivation at 55°C and pH 7.0. Cell culture and crude enzyme of the isolates were tested on chitin of B. tabaci and the effect was observed using a microscope and sterile water was used as a negative control. Hydrolytic observation showed that crude enzyme of I.21 isolate could degrade chitin of B. tabaci exoskeleton and the activity was better than that of I.5 isolate. Conclusion: Chitinase produced by Bacillus cereus I.21 strain has potential application as biocontrol agents for B. tabaci.

  18. Biology of Bemisia tuberculata Bondar (Aleyrodidae) and parasitism by Encarsia porteri (Mercet, 1928) (Hymenoptera, Aphelinidae) on cassava plants.

    Science.gov (United States)

    Andrade Filho, N N; Roel, A R; Penteado-Dias, A M; Costa, R B

    2012-11-01

    The whitefly Bemisia tuberculata has caused serious damage to cassava producing areas in the state of Mato Grosso do Sul. However, little is known about the biological characteristics of this species. The objective of this study was therefore, to monitor the development of this species bred on cassava plants under controlled greenhouse conditions, and to determine its most vulnerable stages and its reproductive capacity, as well as measuring the length and width each stage of development. To obtain these data, adult individuals were kept in voile traps on cassava leaves of five different plants, totalling ten leaves. After 24 hours the leaves were removed from the traps thus making each egg-laden leaf an experimental unit. The lowest mortality rate was record in the last nymphal stage ('pupae) compared with the other development stages. The highest mortality occurred in the nymphs at the 2nd and 3rd instars. Each female laid an average of 6.3 eggs in 24 hours. Thirteen days after egg laying, every one of the nymphs was fixed on the leaves of cassava plants. From the egg laying stage up until the adult stage, the process took 26 days. The proportion of females was 73.5%. The average size of the B. tuberculata egg was 163.22 µm in length and 72.39 µm in width and the "pupae" is 915.82 µm in length and 628.71 µm in width. The measurements of males were 797.16 µm in length and 200.81 µm in width and the length females 916.12 µm in length and 338.99 µm in width. The parasitoid Encarsia porteri (Mercet, 1928) (Hymenoptera, Aphelinidae) was found in the insect stock culture.

  19. Induced changes in the antioxidative compounds of Vigna mungo genotypes due to infestation by Bemisia tabaci (Gennadius).

    Science.gov (United States)

    Taggar, Gaurav Kumar; Gill, Ranjit Singh; Gupta, Anil Kumar; Singh, Sarvjeet

    2014-11-01

    Antioxidative compounds were quantified from the leaves of nine black gram (Vigna mungo (L.) Hepper) genotypes over a period of two years, for potential whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleryrodidae) resistance. Oviposition preference, nymphal and adult development were evaluated under screen-house conditions. Biochemical analysis revealed that higher per cent increase in the total phenol and o-dihydroxy phenol contents both at 30 and 50 days after sowing was evident in moderately resistant genotypes NDU 5-7 (49.6 and 50.8%, respectively) and KU 99-20 (47.8 and 50.8%, respectively) under whitefly stress conditions as compared to non-stressed plants. Tannin and flavonol contents in leaves increased to varying degrees (up to 11.1 and 7.1%, respectively) in resistant plants after whitefly infestation, indicating that the changes in tannin and flavonol contents were closely associated with the resistance to whitefly. Correlation studies relating leaf content of black gram antioxidative compounds from different genotypes with whitefly population were also worked out. Total phenols (r = -0.71 & -0.88), o- dihydroxy phenols (r = -0.56 & -0.76), flavonols (r = -0.80 & -0.81) and tannins (r= -0.16 & -0.26) showed significant negative correlation with whitefly population (nymphs and adults) suggesting that enhanced level of these biochemicals may contribute to bioprotection of black gram plants against B. tabaci infestation. Comparatively higher level of resistance in genotype NDU 5-7 and KU 99-20 can serve as base for genetic improvement of black gram, focusing on the development of resistant varieties to B. tabaci.

  20. DNA barcoding of Bemisia tabaci complex (Hemiptera: Aleyrodidae) reveals southerly expansion of the dominant whitefly species on cotton in Pakistan.

    Science.gov (United States)

    Ashfaq, Muhammad; Hebert, Paul D N; Mirza, M Sajjad; Khan, Arif M; Mansoor, Shahid; Shah, Ghulam S; Zafar, Yusuf

    2014-01-01

    Although whiteflies (Bemisia tabaci complex) are an important pest of cotton in Pakistan, its taxonomic diversity is poorly understood. As DNA barcoding is an effective tool for resolving species complexes and analyzing species distributions, we used this approach to analyze genetic diversity in the B. tabaci complex and map the distribution of B. tabaci lineages in cotton growing areas of Pakistan. Sequence diversity in the DNA barcode region (mtCOI-5') was examined in 593 whiteflies from Pakistan to determine the number of whitefly species and their distributions in the cotton-growing areas of Punjab and Sindh provinces. These new records were integrated with another 173 barcode sequences for B. tabaci, most from India, to better understand regional whitefly diversity. The Barcode Index Number (BIN) System assigned the 766 sequences to 15 BINs, including nine from Pakistan. Representative specimens of each Pakistan BIN were analyzed for mtCOI-3' to allow their assignment to one of the putative species in the B. tabaci complex recognized on the basis of sequence variation in this gene region. This analysis revealed the presence of Asia II 1, Middle East-Asia Minor 1, Asia 1, Asia II 5, Asia II 7, and a new lineage "Pakistan". The first two taxa were found in both Punjab and Sindh, but Asia 1 was only detected in Sindh, while Asia II 5, Asia II 7 and "Pakistan" were only present in Punjab. The haplotype networks showed that most haplotypes of Asia II 1, a species implicated in transmission of the cotton leaf curl virus, occurred in both India and Pakistan. DNA barcodes successfully discriminated cryptic species in B. tabaci complex. The dominant haplotypes in the B. tabaci complex were shared by India and Pakistan. Asia II 1 was previously restricted to Punjab, but is now the dominant lineage in southern Sindh; its southward spread may have serious implications for cotton plantations in this region.

  1. Sequencing and comparison of the Rickettsia genomes from the whitefly Bemisia tabaci Middle East Asia Minor I.

    Science.gov (United States)

    Zhu, Dan-Tong; Xia, Wen-Qiang; Rao, Qiong; Liu, Shu-Sheng; Ghanim, Murad; Wang, Xiao-Wei

    2016-08-01

    The whitefly, Bemisia tabaci, harbors the primary symbiont 'Candidatus Portiera aleyrodidarum' and a variety of secondary symbionts. Among these secondary symbionts, Rickettsia is the only one that can be detected both inside and outside the bacteriomes. Infection with Rickettsia has been reported to influence several aspects of the whitefly biology, such as fitness, sex ratio, virus transmission and resistance to pesticides. However, mechanisms underlying these differences remain unclear, largely due to the lack of genomic information of Rickettsia. In this study, we sequenced the genome of two Rickettsia strains isolated from the Middle East Asia Minor 1 (MEAM1) species of the B. tabaci complex in China and Israel. Both Rickettsia genomes were of high coding density and AT-rich, containing more than 1000 coding sequences, much larger than that of the coexisted primary symbiont, Portiera. Moreover, the two Rickettsia strains isolated from China and Israel shared most of the genes with 100% identity and only nine genes showed sequence differences. The phylogenetic analysis using orthologs shared in the genus, inferred the proximity of Rickettsia in MEAM1 and Rickettsia bellii. Functional analysis revealed that Rickettsia was unable to synthesize amino acids required for complementing the whitefly nutrition. Besides, a type IV secretion system and a number of virulence-related genes were detected in the Rickettsia genome. The presence of virulence-related genes might benefit the symbiotic life of the bacteria, and hint on potential effects of Rickettsia on whiteflies. The genome sequences of Rickettsia provided a basis for further understanding the function of Rickettsia in whiteflies. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  2. Direct and Indirect Impacts of Infestation of Tomato Plant by Myzus persicae (Hemiptera: Aphididae) on Bemisia tabaci (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    Tan, Xiao-Ling; Wang, Su; Ridsdill-Smith, James; Liu, Tong-Xian

    2014-01-01

    The impacts of infestation by the green peach aphid (Myzus persicae) on sweetpotato whitefly (Bemisia tabaci) settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of whitefly release, and leaf positions on the plants. The results demonstrated that B. tabaci preferred to settle on the plant leaves that had not been infested by aphids when they had a choice. The plant leaves on which aphids were still present (direct effect) had fewer whiteflies than those previously infested by aphids (indirect effect). The whiteflies were able to settle on the plant which aphids had previously infested, and also could settle on leaves with aphids if no uninfested plants were available. Tests of direct factors revealed that duration of aphid infestation had a stronger effect on whitefly landing preference than aphid density; whitefly preference was the least when 20 aphids fed on the leaves for 72 h. Tests of indirect effects revealed that the major factor that affected whitefly preference for a host plant was the interval between the time of aphid removal after infestation and the time of whitefly release. The importance of the four factors that affected the induced plant defense against whiteflies can be arranged in the following order: time intervals between aphid removal and whitefly release > durations of aphid infestation > density of aphids > leaf positions on the plants. In conclusion, the density of aphid infestation and time for which they were feeding influenced the production of induced compounds by tomatoes, the whitefly responses to the plants, and reduced interspecific competition. PMID:24710393

  3. Assessment of potential sublethal effects of various insecticides on key biological traits of the tobacco whitefly, Bemisia tabaci.

    Science.gov (United States)

    He, Yuxian; Zhao, Jianwei; Zheng, Yu; Weng, Qiyong; Biondi, Antonio; Desneux, Nicolas; Wu, Kongming

    2013-01-01

    The tobacco whitefly Bemisia tabaci is one of the most devastating pests worldwide. Current management of B. tabaci relies upon the frequent applications of insecticides. In addition to direct mortality by typical acute toxicity (lethal effect), insecticides may also impair various key biological traits of the exposed insects through physiological and behavioral sublethal effects. Identifying and characterizing such effects could be crucial for understanding the global effects of insecticides on the pest and therefore for optimizing its management in the crops. We assessed the effects of sublethal and low-lethal concentrations of four widely used insecticides on the fecundity, honeydew excretion and feeding behavior of B. tabaci adults. The probing activity of the whiteflies feeding on treated cotton seedlings was recorded by an Electrical Penetration Graph (EPG). The results showed that imidacloprid and bifenthrin caused a reduction in phloem feeding even at sublethal concentrations. In addition, the honeydew excretions and fecundity levels of adults feeding on leaf discs treated with these concentrations were significantly lower than the untreated ones. While, sublethal concentrations of chlorpyrifos and carbosulfan did not affect feeding behavior, honeydew excretion and fecundity of the whitefly. We demonstrated an antifeedant effect of the imidacloprid and bifenthrin on B. tabaci, whereas behavioral changes in adults feeding on leaves treated with chlorpyrifos and carbosulfan were more likely caused by the direct effects of the insecticides on the insects' nervous system itself. Our results show that aside from the lethal effect, the sublethal concentration of imidacloprid and bifenthrin impairs the phloem feeding, i.e. the most important feeding trait in a plant protection perspective. Indeed, this antifeedant property would give these insecticides potential to control insect pests indirectly. Therefore, the behavioral effects of sublethal concentrations of

  4. Impact of Bemisia argentifolii (Homoptera: Auchenorrhyncha: Aleyrodidae) infestation and squash silverleaf disorder on zucchini yield and quality.

    Science.gov (United States)

    Chen, Jiang; McAuslane, Heather J; Carle, R Bruce; Webb, Susan E

    2004-12-01

    Fruit yield and quality of zucchini, Cucurbita pepo L., plants infested with Bemisia argentifolii Bellows & Perring were evaluated in a screenhouse under spring and fall growing conditions by using closely related sister lines that were either susceptible (ZUC61) or tolerant (ZUC76-SLR) to squash silverleaf disorder. Our objective was to test separately the effects of level of whitefly infestation and expression of silverleaf symptoms on zucchini yield and quality. In a second experiment, yield and quality of fruit produced by silverleaf-tolerant zucchini genotypes incorporating two different sources of tolerance (ZUC76-SLR and ZUC33-SLR/PMR) were compared with that of 'Zucchini Elite', a silverleaf-susceptible commercial hybrid. Zucchini fruit yield was reduced in plants exposed to repeated infestations of whiteflies in spring and fall of both experiments. In addition, fruit grew to harvestable size more slowly under the highest whitefly infestations. Fruit quality was reduced at high infestations because of uneven and reduced pigmentation. The fruit yield and quality of ZUC61 and ZUC76-SLR were similarly affected by whitefly infestation despite differences in their susceptibility to squash silverleaf disorder. Fruit from infested plants showed decreased levels of chlorophyll and carotenoids causing the "blanching" of the fruit that is associated with loss of quality and reduced marketability. Leaves of infested plants of all genotypes had reduced levels of photosynthetic and photoprotectant pigments, possibly leading to reduced photosynthesis and consequently reduced yield. We conclude that feeding by high whitefly populations rather than expression of squash silverleaf disorder is responsible for yield and quality reduction in zucchini.

  5. Bioassay evaluation of the entomopathogenic fungi, Beauveria bassaina Vuellemin against eggs and nymphs of Bemisia tabaci Gennadius (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Al-Deghairi, Mohammad A

    2008-06-15

    This study was carried out to determine the lethal effect of the entomopathogenic fungi, Beauveria bassaina Vuell. on eggs, young and old nymphs of the whitefly, Bemisia tabaci Genn. Mortality percentage was significantly differed based on stage of B. tabaci and conidial concentrations of B. bassina. Average of the infection level to insect was very low particularly in eggs with only 4.49%, even with higher conidial concentrations (6 x 10(6) conidia mL(-1)). Whereas, it was higher with 1st and 2nd instars (42.045%) and 3rd and 4th instars (35.93%). Three parameters was assessed with B. tabaci eggs, namely; egg infection, egg hatchability and crawlers emergence. Egg mortality percentages averaged 1.2, 4.27 and 8.0% with fungal concentration 2 x 10(6), 4 x 10(6) and 6 x 10(6) conidia mL(-1), respectively. Daily infection percentages were varied depend upon the conidial concentration where the highest infection rate of eggs was occurred with 6 x 10(6), followed by 4 x 10(6) conidia mL(-1). Egg hatch was very high, while the mortality among the emerged crawlers was neglectable compared with the check. Efficiency of B. bassaina on whitefly nymphs also was varied based on the insect instar and fungal concentration. Mortality percentages were obviously higher to young nymphs (1st and 2nd instars) than to older ones (3rd and 4th instars). The results indicated that nymphs were highly susceptible to fungal treatment compared with eggs. Additionally, pathogenicity and virulence of B. bassaina against B. tabaci immatures was not indicated by LC50 only, but also, by the time in days (LT50) required to achieve 50% mortality of an insect.

  6. Biological traits and Life table parameters A and B biotype of Bemisia tabaci (Genn. on cotton and rapeseed

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    Mohammad Amin Samih

    2014-06-01

    Full Text Available The aim of this work was to construct life table of Bemisia tabaci (Gen. A and B (silverleaf whitefly B. argentifolii Bellows and Perring biotype (Hem.: Aleyrodidae on two host plants; cotton, (Gossypium hirsutum L. and rapeseed, (Brassica napus L.. Experiments were conducted in a growth chamber under 24 ± 2ºC, 55±3% RH and 16:8 (L:D h photoperiod on caged plants of cotton G. hirsutum L. (Varamin 76 variety and rapeseed B. napus L. (global variety. The intrinsic rate of natural increase (r m, net reproductive rate (R0 and mean generation time (T for B. tabaci A biotype was 0.1010 females per female per day, 18.4075 females per female and 30.079 day (d on cotton; 0.1286, 30.6760 and 26.77 d on rapeseed; and for B biotype (B. argentifolii those above respective parameters averaged 0.1033, 27.8426 and 32.74 d on cotton and 0.1750, 40.75 and 21.27 d on rapeseed. The total survival of A and B biotype from the egg to adult on cotton was 22.08 and 22.25, respectively. The results showed significant differences between the two biotype reared on either host plant for gross reproductive rate (GRR, net reproductive rate (R0 or NRR, intrinsic rates of increase (r m, finite rate of increase (λ, doubling time (DT and mean generation times (Tc. To obtain a better understanding of the biology of these biotypes, Stable age distribution (Cx and some other aspects of life history related to their hosts were also studied. Based upon the results, both biotypes showed a greater reproduction capacity on rapeseed than on cotton. Thus, rapeseed was more suitable host than cotton for two biotypes and this was an important factor in host plant selection for optimizing the control strategies of these major pests.

  7. Survival of Bemisia tabaci and activity of plant defense-related enzymes in genotypes of Capsicum annuum L.

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    Luis Latournerie-Moreno

    2015-03-01

    Full Text Available The whitefly Bemisia tabaci (Gennadius, 1889 is a major plant pest of horticultural crops from the families Solanaceae, Fabaceae and Cucurbitaceae in Neotropical areas. The exploration of host plant resistance and their biochemical mechanisms offers an excellent alternative to better understand factors affecting the interaction between phytophagous insect and host plant. We evaluated the survival of B. tabaci in landrace genotypes of Capsicum annuum L., and the activity of plant defense-related enzymes (chitinase, polyphenoloxidase, and peroxidase. The landrace genotypes Amaxito, Tabaquero, and Simojovel showed resistance to B. tabaci, as we observed more than 50% nymphal mortality, while in the commercial susceptible genotype Jalapeño mortality of B. tabaci nymphs was not higher than 20%. The activities of plant defense-related enzymes were significantly different among pepper genotypes (P < 0.05. Basal activities of chitinase, polyphenoloxidase and peroxidase were significantly lower or equal in landrace genotypes than that of the commercial genotype Jalapeño. The activity of plant enzymes was differential among pepper genotypes (P < 0.05. For example, the activity of chitinase enzyme generally was higher in non-infested plants with B. tabaci than those infested. Instead polyphenoloxidase ('Amaxito' and 'Simojovel' and peroxidase enzymes activities ('Tabaquero' increased in infested plants (P < 0.05. We conclude that basal activities of plant defense-related enzymes could be act through other mechanism plant induction, since plant defense-related enzymes showed a different induction response to B. tabaci. We underlined the role of polyphenoloxidase as plant defense in the pepper genotype Simojovel related to B. tabaci.

  8. Temporal changes of symbiont density and host fitness after rifampicin treatment in a whitefly of the Bemisia tabaci species complex.

    Science.gov (United States)

    Shan, Hong-Wei; Zhang, Chang-Rong; Yan, Ting-Ting; Tang, Hai-Qin; Wang, Xiao-Wei; Liu, Shu-Sheng; Liu, Yin-Quan

    2016-04-01

    Microbial symbionts are essential or important partners to phloem-feeding insects. Antibiotics have been used to selectively eliminate symbionts from their host insects and establish host lines with or without certain symbionts for investigating functions of the symbionts. In this study, using the antibiotic rifampicin we attempted to selectively eliminate certain symbionts from a population of the Middle East-Asia Minor 1 whitefly of the Bemisia tabaci species complex, which harbors the primary symbiont "Candidatus Portiera aleyrodidarum" and two secondary symbionts "Candidatus Hamiltonella defensa" and Rickettsia. Neither the primary nor the secondary symbionts were completely depleted in the adults (F0) that fed for 48 h on a diet treated with rifampicin at concentrations of 1-100 μg/mL. However, both the primary and secondary symbionts were nearly completely depleted in the offspring (F1) of the rifampicin-treated adults. Although the F1 adults produced some eggs (F2), most of the eggs failed to hatch and none of them reached the second instar, and consequently the rifampicin-treated whitefly colony vanished at the F2 generation. Interestingly, quantitative polymerase chain reaction assays showed that in the rifampicin-treated whiteflies, the density of the primary symbiont was reduced at an obviously slower pace than the secondary symbionts. Mating experiments between rifampicin-treated and untreated adults demonstrated that the negative effects of rifampicin on host fitness were expressed when the females were treated by the antibiotic, and whether males were treated or not by the antibiotic had little contribution to the negative effects. These observations indicate that with this whitefly population it is not feasible to selectively eliminate the secondary symbionts using rifampicin without affecting the primary symbiont and establish host lines for experimental studies. However, the extinction of the whitefly colony at the second generation after

  9. The Dynamics and Environmental Influence on Interactions Between Cassava Brown Streak Disease and the Whitefly, Bemisia tabaci.

    Science.gov (United States)

    Jeremiah, S C; Ndyetabula, I L; Mkamilo, G S; Haji, S; Muhanna, M M; Chuwa, C; Kasele, S; Bouwmeester, H; Ijumba, J N; Legg, J P

    2015-05-01

    Cassava brown streak disease (CBSD) is currently the most significant virus disease phenomenon affecting African agriculture. In this study, we report results from the most extensive set of field data so far presented for CBSD in Africa. From assessments of 515 farmers' plantings of cassava, incidence in the Coastal Zone of Tanzania (46.5% of plants; 87% of fields affected) was higher than in the Lake Zone (22%; 34%), but incidences for both zones were greater than previous published records. The whitefly vector, Bemisia tabaci, was more abundant in the Lake Zone than the Coastal Zone, the reverse of the situation reported previously, and increased B. tabaci abundance is driving CBSD spread in the Lake Zone. The altitudinal "ceiling" previously thought to restrict the occurrence of CBSD to regions <1,000 masl has been broken as a consequence of the greatly increased abundance of B. tabaci in mid-altitude areas. Among environmental variables analyzed, minimum temperature was the strongest determinant of CBSD incidence. B. tabaci in the Coastal and Lake Zones responded differently to environmental variables examined, highlighting the biological differences between B. tabaci genotypes occurring in these regions and the superior adaptation of B. tabaci in the Great Lakes region both to cassava and low temperature conditions. Regression analyses using multi-country data sets could be used to determine the potential environmental limits of CBSD. Approaches such as this offer potential for use in the development of predictive models for CBSD, which could strengthen country- and continent-level CBSD pandemic mitigation strategies.

  10. Actividad fagodisuasiva de las plantas Tithonia diversifolia y Montanoa hibiscifolia (Asteraceae sobre adultos del insecto plaga Bemisia tabaci (Homoptera: Aleyrodidae

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    Gina Bagnarello

    2009-12-01

    Full Text Available Bemisia tabaci (Gennadius (Homoptera: Aleyrodidae es una plaga polífaga, cosmopolita y de gran relevancia mundial, sobre todo como vector de virus en numerosos cultivos, por lo que sería deseable un enfoque preventivo para su manejo. En tal sentido, podría recurrirse a la utilización de sustancias repelentes o disuasivas, algunas de ellas presentes en plantas tropicales, lo cual contribuiría al aprovechamiento de la rica biodiversidad mesoamericana. Por tanto, se evaluó la posible actividad fagodisuasiva sobre los adultos de B. tabaci de dos especies silvestres de la familia Asteraceae: titonia (Tithonia diversifolia (Hemsl. A. Gray y tora (Montanoa hibiscifolia Benth.. Para ello, en condiciones de invernadero se evaluaron los extractos crudos y cuatro fracciones (hexano, diclorometano, acetato de etilo y metanol de ambas especies, a los cuales se les hizo un análisis fitoquímico (tamizaje el cual permitió determinar cuáles metabolitos presentes en T. diversifolia y M. hibiscifolia podrían causar fagodisuasión en B. tabaci. Se realizaron dos tipos de experimentos: de escogencia restringida y de escogencia irrestricta. En los primeros, cada fracción se evaluó a cuatro dosis (0.1, 0.5, 1.0 y 1.5% v/v, y se comparó con cuatro tratamientos testigo: aceite agrícola, endosulfán, un emulsificante (Citowett y un testigo absoluto (agua. Se asperjaron plantas de tomate colocadas dentro de jaulas de manga, donde se liberaron 50 adultos de B. tabaci. Para determinar si existía fagodisuasión se utilizó como criterio el número de adultos posados a las 48h. Para el experimento de escogencia irrestricta se utilizaron las dos concentraciones más altas (1.0 y 1.5% del extracto crudo de cada especie y se compararon con el aceite agrícola y agua. Los extractos crudos de titonia y tora causaron fagodisuasión, y para ambas especies la fracción de metanol fue la que más sobresalió. En conclusión, los resultados obtenidos en los bioensayos

  11. Preferência para oviposição e ciclo de vida de mosca-negra- dos-citros Aleurocanthus woglumi Ashby em espécies frutíferas

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    Gislane da Silva Lopes

    2013-09-01

    Full Text Available Aleurocanthus woglumi Ashby conhecida popularmente como mosca-negra-dos-citros é considerada praga quarentenária A2 no Brasil e ocasiona prejuízo em diversas frutíferas, principalmente em citros (laranja, limão e tangerina. Poucas são as pesquisas relacionadas aos seus aspectos biológicos nas condições ambientais brasileiras. Nesse sentido, o objetivo da pesquisa foi verificar a preferência de oviposição e a duração do ciclo de vida de A. woglumi em diferentes hospedeiros. A pesquisa foi conduzida em casa de vegetação, durante o período de março de 2009 a março de 2010. Foram realizados testes de preferência sem chance de escolha em seis hospedeiros, simultaneamente, em períodos de 48 e 72 horas, além da biologia comparada em mangueira e laranjeira. Foram observados nos testes que A. woglumi apresenta preferência por ovipositar nas espécies cítricas (limoeiro, laranjeira e tangerineira, mantendo um padrão de não preferência em cajueiro e goiabeira. Os hospedeiros laranjeira e mangueira não interferiram no ciclo biológico da praga.

  12. Atividade relativa da catalase de losna-branca (Parthenium hysterophorus comparada à de outras espécies daninhas Catalase relative activity of ragweed (Parthenium hysterophorus compared to that of other weed species

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    S.J.P. Carvalho

    2012-06-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a atividade relativa da catalase em extrato aquoso de losna-branca (Parthenium hysterophorus, bem como comparála à atividade da catalase de outras espécies daninhas. O trabalho constou de três fases, que envolveram a padronização do método, comparação da atividade relativa da catalase de plantas da família Asteraceae e comparação com outras 11 espécies daninhas, sendo estas: Euphorbia heterophylla, Alternanthera tenella, Cenchrus echinatus, Panicum maximum, Amaranthus viridis, Ipomoea hederifolia, Galinsoga parviflora, Bidens pilosa, Sonchus oleraceus, Cyperus rotundus e Commelina benghalensis. Observou-se resposta linear crescente da reação entre extrato aquoso de losna-branca e peróxido de hidrogênio, em razão da concentração do extrato vegetal. Em todas as fases, a atividade relativa da catalase de extrato de losna-branca foi superior à atividade da catalase das demais espécies daninhas. Com os dados obtidos nas três fases, conclui-se que a maior atividade relativa observada para a catalase da losnabranca contribui significativamente para a tolerância dessa espécie ao herbicida paraquat. Essa maior atividade pode ser consequência da maior concentração enzimática nas células ou devido à maior atividade intrínseca da enzima (afinidade enzima-substrato, havendo necessidade de estudos mais precisos para essa conclusão.This work was carried out to evaluate catalase relative activity of ragweed (Parthenium hysterophorus aqueous extract, as well as to compare it with catalase activity of other weed species. It consisted of three phases, involving method standardization, comparison of the catalase relative activity in Asteraceae family plants and that of ragweed catalase activity with the following 11 weed species: Euphorbia heterophylla, Alternanthera tenella, Cenchrus echinatus, Panicum maximum, Amaranthus viridis, Ipomoea hederifolia, Galinsoga parviflora

  13. Silicon leaf application and physiological quality of white oat and wheat seedsAplicação foliar de silício e qualidade fisiológica de sementes de aveia-branca e trigo

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    Mariane Sayuri Ishizuka

    2012-10-01

    Full Text Available Plant nutrition can positively influence quality of seeds by improving plant tolerance to adverse climate. In this context, silicon is currently considered a micronutrient and it is beneficial to plant growth, especially Poaceaes such as white oat and wheat, thereby improving physiological quality of seeds. This study had the objective of evaluating the effects of silicon leaf application on plant tillering, silicon levels and physiological quality of white oat and wheat seeds besides establishing correlations between them. Two experiments were carried out in winter with white oat and wheat. The experimental design was the completely randomized block with eight replications. Treatments consisted of foliar application of silicon (0.8% of soluble silicon, as stabilized orthosilicic acid and a control (with no application. Silicon levels in leaves were determined at flowering whereas the number of plants and panicles/spikes per area was counted right before harvest. Seed quality was evaluated right after harvest through mass, germination and vigor tests. Data was submitted to variance analysis and means were compared by the Tukey test at a probability level of 5%. Person’s linear correlation test was performed among silicon level in plants, tillering and seed quality data. Silicon leaf application increases root and total length of white oat seedlings as an effect of higher Si level in leaves. Silicon leaf application increases mass of wheat seeds without affecting germination or vigor. A nutrição das plantas pode influenciar positivamente a qualidade das sementes por proporcionar maior tolerância às adversidades climáticas. Neste contexto, o silício é atualmente considerado um micronutriente e tem efeito benéfico no crescimento das plantas, especialmente Poaceaes como aveia-branca e trigo, consequentemente melhorando a qualidade fisiológica das sementes. Este estudo objetivou avaliar os efeitos da aplicação foliar de silício no

  14. Diversidade de moscas-das-frutas, suas plantas hospedeiras e seus parasitóides nas regiões Norte e Noroeste do Estado do Rio de Janeiro, Brasil Fruit fly diversity, their host plants and their parasitoids in the northern and northwestern regions of Rio de Janeiro State, Brazil

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    Michela Rocha Leal

    2009-06-01

    Full Text Available Em razão da exploração crescente da fruticultura nas regiões Norte e Noroeste do Estado do Rio de Janeiro e da importância econômica e quarentenária das moscas-das-frutas para essa atividade agrícola no mundo, este estudo foi conduzido em cinco municípios dessas regiões: Cambuci, Campos dos Goytacazes, Itaocara, São Francisco do Itabapoana e São João da Barra, com objetivo de registrar as espécies de moscas-das-frutas, suas plantas hospedeiras e seus parasitóides. Os espécimes foram coletados por meio de armadilhas McPhail com solução aquosa de proteína hidrolisada a 5% e em amostras de frutos. Nas armadilhas, 4% do total de moscas-das-frutas capturadas foram Ceratitis capitata e 96% eram do gênero Anastrepha, num total de 15 espécies. Das moscas capturadas nas armadilhas, apenas seis espécies infestaram frutos entre as 12 espécies de fruteiras amostradas. Fruteiras das famílias Anacardiaceae, Malpighiaceae, Myrtaceae, Oxalidaceae, Passifloraceae e Sapotaceae foram plantas hospedeiras de moscas-das-frutas. Apenas três espécies de Anastrepha (A. fraterculus, A. sororcula e A. zenildae infestaram goiabas da variedade comercial Paluma. Os parasitóides de larvas de moscas-das-frutas encontrados foram Doryctobracon areolatus e Aganaspis pelleranoi, parasitando-as em frutos de goiabeira e de outras fruteiras nessas regiões.Due to the increase in fruit crops acreage in the northern and northwestern regions of Rio de Janeiro State and to the economic and quarantine importance of the fruit flies to this agricultural activity in the world, this study was carried out in five municipalities of these regions: Cambuci, Campos dos Goytacazes, Itaocara, São Francisco do Itabapoana, and São João da Barra, aiming to study the fruit fly species, their host plants and their parasitoids. The specimens were collected using McPhail traps with aqueous solution of hydrolyzed protein to 5% and in fruit samples. In the traps, 4% of the total

  15. Observações sobre a ocorrência de Mosca-Negra-dos-Citros, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Sternorrhyncha: Aleyrodidae no estado do Amazonas Observation on the occurrence of the citrus blackfly Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Sternorrhyncha: Aleyrodidae in the Amazonas state

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    Beatriz Ronchi-Teles

    2009-03-01

    Full Text Available A mosca-negra-dos-citros (Aleurocanthus woglumi Ashby é uma importante praga dos citros de origem asiática. Foi detectada no Brasil pela primeira vez em Belém-PA em 2001. Este trabalho tem como objetivo registrar a ocorrência de mosca-negra-dos-citros no estado do Amazonas, sua distribuição geográfica e estudos de biologia em condições de laboratório. A mosca-negra encontra-se atualmente disseminada em mais da metade dos municípios paraenses. No Amazonas foi detectada em junho de 2004 em Manaus e atualmente encontra-se disseminada em toda a área urbana deste município, ocorrendo também em Itacoatiara, Rio Preto da Eva e Iranduba. Em observações feitas em condições de laboratório em Manaus-AM, foi verificado que o ciclo de ovo-adulto foi de 71,76±2,07 dias, caracterizando como uma espécie multivoltina.The citrus blackfly Aleurocanthus woglumi Ashby, pest of citrus in Asian is considered important pest. It was detected for the first time in Belém, PA in 2001. The objective of this work was to report occurrence of the citrus blackfly in Amazon state. Nowadays is found in the majority of the oriental amazon counties. In Manaus, Amazonas was detected in June 2004, actually disseminated in the urban area and in Itacoatiara, Rio Preto da Eva and Iranduba counties. In observations in laboratory in Manaus-AM, was verified that the egg-adult cycle belonged to 71,76±2,07 days, characterizing as a multivoltin species.

  16. Inter-seasonal population dynamics and pest status of Bemisia tabaci (Gennadius) biotype B in an Australian cropping system.

    Science.gov (United States)

    Sequeira, R V; Shields, A; Moore, A; De Barro, P

    2009-08-01

    Bemisia tabaci, biotype B, commonly known as the silverleaf whitefly (SLW) is an alien species that invaded Australia in the mid-90s. This paper reports on the invasion ecology of SLW and the factors that are likely to have contributed to the first outbreak of this major pest in an Australian cotton cropping system. Population dynamics of SLW within whitefly-susceptible crop (cotton and cucurbit) and non-crop vegetation (sowthistle, Sonchus spp.) components of the cropping system were investigated over four consecutive growing seasons (September-June) 2001/02-2004/05 in the Emerald Irrigation Area (EIA) of Queensland, Australia. Based on fixed geo-referenced sampling sites, variation in spatial and temporal abundance of SLW within each system component was quantified to provide baseline data for the development of ecologically sustainable pest management strategies. Parasitism of large (3rd and 4th instars) SLW nymphs by native aphelinid wasps was quantified to determine the potential for natural control of SLW populations. Following the initial outbreak in 2001/02, SLW abundance declined and stabilised over the next three seasons. The population dynamics of SLW is characterised by inter-seasonal population cycling between the non-crop (weed) and cotton components of the EIA cropping system. Cotton was the largest sink for and source of SLW during the study period. Over-wintering populations dispersed from weed host plant sources to cotton in spring followed by a reverse dispersal in late summer and autumn to broad-leaved crops and weeds. A basic spatial source-sink analysis showed that SLW adult and nymph densities were higher in cotton fields that were closer to over-wintering weed sources throughout spring than in fields that were further away. Cucurbit fields were not significant sources of SLW and did not appear to contribute significantly to the regional population dynamics of the pest. Substantial parasitism of nymphal stages throughout the study period

  17. Age-specific interaction between the parasitoid, Encarsia formosa and its host, the silverleaf whitefly, Bemisia tabaci (Strain B).

    Science.gov (United States)

    Hu, Jing S; Gelman, Dale B; Blackburn, Michael B

    2003-01-01

    The effect of hostage, the instar of Bemisia tabaci (Gennadius) parasitized, on the growth and development of Encarsia formosa (Gahan) was studied. E. formosa was able to parasitize and complete its life cycle no matter which instar of B. tabaci (Strain B), [also identified as B. argentifolii (Bellows and Perring)], was provided for oviposition, but parasitoid development was significantly slower when 1st or 2nd instar B. tabaci rather than 3rd or 4th instars were parasitized. Host age influenced the day on which E. formosa nymphs hatching from eggs was first observed. Mean embryonic development was significantly longer when 1st (5.4 days) rather than 2nd, 3rd or 4th instars (4.1, 3.4 and 3.5 days, respectively) were parasitized. The duration of the 1st instar parasitoid and the pupa, but not the 2nd or 3rd instar parasitoid, were also significantly greater when 1st instars were parasitized than when older host instars were parasitized. Interestingly, no matter which instar was parasitized, the parasitoid did not molt to the 3rd instar until the 4th instar host had reached a depth of about 0.23 mm (Stage 4-5) and had initiated the nymphal-adult molt and adult development. Histological studies revealed that whitefly eye and wing structures had either disintegrated or were adult in nature whenever a 3rd instar parasitoid was present. It appears, then, that the molt of the parasitoid to its last instar is associated with the host whitefly's nymphal-adult molt. However, the initiation of the host's final molt, while a prerequisite for the parasitoid's 2nd-3rd instar molt, did not necessarily trigger this molt. In contrast to its significant effect on various aspects of parasitoid development, host instar did not significantly influence the mean size of the parasitoid larva, pupa, or adult. Larval and pupal length and adult head width were similar for all parasitoids, regardless of which host instar was parasitized as was adult longevity. Adult parasitoid emergence was

  18. Age-specific interaction between the parasitoid, Encarsia formosa and its host, the silverleaf whitefly, Bemisia tabaci (Strain B

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    Jing S. Hu

    2003-08-01

    Full Text Available The effect of hostage, the instar of Bemisia tabaci (Gennadius parasitized, on the growth and development of Encarsia formosa (Gahan was studied. E. formosa was able to parasitize and complete its life cycle no matter which instar of B. tabaci (Strain B, [also identified as B. argentifolii (Bellows and Perring], was provided for oviposition, but parasitoid development was significantly slower when 1st or 2nd instar B. tabaci rather than 3rd or 4th instars were parasitized. Host age influenced the day on which E. formosa nymphs hatching from eggs was first observed. Mean embryonic development was significantly longer when 1st (5.4 days rather than 2nd, 3rd or 4th instars (4.1, 3.4 and 3.5 days, respectively were parasitized. The duration of the 1st instar parasitoid and the pupa, but not the 2nd or 3rd instar parasitoid, were also significantly greater when 1st instars were parasitized than when older host instars were parasitized. Interestingly, no matter which instar was parasitized, the parasitoid did not molt to the 3rd instar until the 4th instar host had reached a depth of about 0.23 mm (Stage 4-5 and had initiated the nymphal-adult molt and adult development. Histological studies revealed that whitefly eye and wing structures had either disintegrated or were adult in nature whenever a 3rd instar parasitoid was present. It appears, then, that the molt of the parasitoid to its last instar is associated with the host whitefly's nymphal-adult molt. However, the initiation of the host's final molt, while a prerequisite for the parasitoid's 2nd-3rd instar molt, did not necessarily trigger this molt. In contrast to its significant effect on various aspects of parasitoid development, host instar did not significantly influence the mean size of the parasitoid larva, pupa, or adult. Larval and pupal length and adult head width were similar for all parasitoids, regardless of which host instar was parasitized as was adult longevity. Adult parasitoid

  19. Critical feeding periods for last instar nymphal and pharate adults of the whiteflies, Trialeurodes vaporariorum and Bemisia tabaci.

    Science.gov (United States)

    Gelman, Dale B; Hu, Jing S

    2007-01-01

    A critical feeding period is the time after which 50% of a given species of insect can be removed from its food source and complete development by undergoing adult eclosion. The critical feeding period was determined for the greenhouse white fly, Trialeurodes vaporariorum, and the sweet potato whitefly, Bemisia tabaci (Biotype B) (Homptera/Hemiptera: Aleyrodidae). Fourth (last) instar and pharate adult whiteflies were removed from green bean leaves, staged, placed on filter paper in small Petri dishes containing drops of water, and observed daily for eclosion. For T. vaporariorum reared at 25 degrees C and L:D 16:8, 55 and 80% adult eclosion were observed when whiteflies were removed at stages 4 (0.23-0.26 mm in body depth) and 5 (> or = 0.27 mm in body depth), respectively, so that at least 50% eclosion was only achieved in this species of whitefly when adult eye development had already been initiated (in Stage 4), and 80% eclosion when adult wing development had been initiated (Stage 5). In contrast, 63% of B. tabaci emerged as adults if removed from the leaf at Stage 3 (0.18-0.22 mm in body depth), and 80% emerged if removed at Stage 4/5, stages in which adult formation had not yet been initiated. The mean number of eggs laid by experimental (those removed at Stages 4-5, 6-7 or 8-9) and control (those that remained on the leaf prior to eclosion) whiteflies, and the mean percent hatch of these eggs were not significantly different in experimental and control groups. Stages 7, 8 and 9 are characterized by a light red adult eye, medium red bipartite adult eye and dark red or red-black bipartite adult eye, respectively. Mean adult longevity also was not significantly different between experimental and control groups. However, for all groups of T. vaporariorum, adult female longevity was significantly (at least 2 times) greater than male longevity. Our results identify the critical feeding periods for last instar/pharate adults of two important pest species of

  20. Host plant pubescence: Effect on silverleaf whitefly, Bemisia argentifolii, fourth instar and pharate adult dimensions and ecdysteroid titer fluctuations

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    Dale B. Gelman

    2003-08-01

    Full Text Available The ability to generate physiologically synchronous groups of insects is vital to the performance of investigations designed to test insect responses to intrinsic and extrinsic stimuli. During a given instar, the silverleaf whitefly, Bemisia argentifolii, increase in depth but not in length or width. A staging system to identify physiologically synchronous 4th instar and pharate adult silverleaf whiteflies based on increasing body depth and the development of the adult eye has been described previously. This study determined the effect of host plant identity on ecdysteroid fluctuations during the 4th instar and pharate adult stages, and on the depth, length and width dimensions of 4th instar/pharate adult whiteflies. When grown on the pubescent-leafed green bean, tomato and poinsettia plants, these stages were significantly shorter and narrower, but attained greater depth than when grown on the glabrous-leafed cotton, collard and sweet potato plants. Thus, leaf pubescence is associated with reduced length and width dimensions, but increased depth dimensions in 4th instars and pharate adults. For all host plants, nymphal ecdysteroid titers peaked just prior to the initiation of adult development. However, when reared on pubescent-leafed plants, the initiation of adult development typically occurred in nymphs that had attained a depth of 0.2 to 0.25 mm (Stage 3 - 4. When reared on glabrous-leafed plants, the initiation of adult development typically occurred earlier, in nymphs that had attained a depth of only 0.15-0.18 mm (Stage 2 Old - early 3. Therefore, based on ecdysteroid concentration, it appears that Stage-2, -3 and -4/5 nymphs reared on pubescent-leafed plants are physiologically equivalent to Stage-1, -2 Young and -2 Old/3, respectively, nymphs reared on glabrous-leafed plants. The host plant affected the width but not the height of the nymphal-adult premolt ecdysteroid peak. However, leaf pubescence was not the determining factor. Thus

  1. Specific cells in the primary salivary glands of the whitefly Bemisia tabaci control retention and transmission of begomoviruses.

    Science.gov (United States)

    Wei, Jing; Zhao, Juan-Juan; Zhang, Tong; Li, Fang-Fang; Ghanim, Murad; Zhou, Xue-Ping; Ye, Gong-Yin; Liu, Shu-Sheng; Wang, Xiao-Wei

    2014-11-01

    The majority of plant viruses are vectored by arthropods via persistent-circulative or noncirculative transmission. Previous studies have shown that specific binding sites for noncirculative viruses reside within the stylet or foregut of insect vectors, whereas the transmission mechanisms of circulative viruses remain ambiguous. Here we report the critical roles of whitefly primary salivary glands (PSGs) in the circulative transmission of two begomoviruses. The Middle East Asia Minor 1 (MEAM1) species of the whitefly Bemisia tabaci complex efficiently transmits both Tomato yellow leaf curl China virus (TYLCCNV) and Tomato yellow leaf curl virus (TYLCV), whereas the Mediterranean (MED) species transmits TYLCV but not TYLCCNV. PCR and fluorescence in situ hybridization experiments showed that TYLCCNV efficiently penetrates the PSGs of MEAM1 but not MED whiteflies. When a fragment of the coat protein of TYLCCNV was exchanged with that of TYLCV, mutated TYLCCNV accumulated in the PSGs of MED whiteflies, while mutant TYLCV was nearly undetectable. Confocal microscopy revealed that virion transport in PSGs follows specific paths to reach secretory cells in the central region, and the accumulation of virions in the secretory region of PSGs was correlated with successful virus transmission. Our findings demonstrate that whitefly PSGs, in particular the cells around the secretory region, control the specificity of begomovirus transmission. Over 75% of plant viruses are transmitted by insects. However, the mechanisms of virus transmission by insect vectors remain largely unknown. Begomoviruses and whiteflies are a complex of viruses and vectors which threaten many crops worldwide. We investigated the transmission of two begomoviruses by two whitefly species. We show that specific cells of the whitefly primary salivary glands control viral transmission specificity and that virion transport in the glands follows specific paths to reach secretory cells in the central region and

  2. Dynamics of biotypes B and Q of the whitefly Bemisia tabaci and its impact on insecticide resistance.

    Science.gov (United States)

    Horowitz, Abraham Rami; Ishaaya, Isaac

    2014-10-01

    The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a key pest in many agricultural crops, including vegetables, ornamentals and field crops. B. tabaci is known for its genetic diversity, which is expressed in a complex of biotypes or, as recently suggested, a complex of distinct cryptic species. The biotypes are largely differentiated on the basis of biochemical or molecular polymorphism and differ in characteristics such as host plant range, attraction by natural enemies, secondary symbionts and expression of insecticide resistance. An extensive survey of B. tabaci biotypes and their impact on insecticide resistance was conducted from 2003 to 2012 in cotton fields and other crops from several locations in Israel. Two biotypes of B. tabaci, B and Q, were identified, and some differences in the biotype dynamics were recorded from different areas. In northern Israel from 2003 to 2007, a higher proportion of the B biotype was consistently found in early season. However, by the end of the season a definite rise of the Q biotype was sampled, ranging from 60 to 100%, along with high resistance to the insect growth regulator (IGR) pyriproxyfen and to a lesser extent to the neonicotinoid insecticides. In fields located in the central part of Israel, the Q biotype was predominant throughout the seasons, with high resistance to pyriproxyfen. Since 2009, a significant shift in the biotype ratios has been observed: the B biotype has come to predominate over the Q biotype ranging up to 90% or more in most fields. At the same time, resistance to the IGR pyriproxyfen was reduced considerably. The possible reasons for the change in the dynamics of B. tabaci biotypes, and its implications for resistance management, are discussed. Strong B. tabaci resistance to pyriproxyfen in Israel has been associated with the Q rather than with the B biotype. The B biotype is more competitive than the Q biotype under untreated conditions. Reduction in the acreage of cotton fields

  3. Transient receptor potential is essential for high temperature tolerance in invasive Bemisia tabaci Middle East Asia minor 1 cryptic species.

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    Zhi-Chuang Lü

    Full Text Available Temperature is an important factor in affecting population dynamics and diffusion distribution of organisms. Alien species can successfully invade and colonize to various temperature environments, and one of important reasons is that alien species have a strong resistance to stress temperature. Recently, researchers have focused on the mechanisms of temperature sensing to determine the sensing and regulation mechanisms of temperature adaptation. The transient receptor potential (TRP is one of the key components of an organism's temperature perception system. TRP plays important roles in perceiving temperature, such as avoiding high temperature, low temperature and choosing the optimum temperature. To assess high temperature sensation and the heat resistance role of the TRP gene, we used 3' and 5' rapid-amplification of cDNA ends to isolate the full-length cDNA sequence of the TRP gene from Bemisia tabaci (Gennadius MEAM1 (Middle East Asia Minor 1, examined the mRNA expression profile under various temperature conditions, and identified the heat tolerance function. This is the first study to characterize the TRP gene of invasive B. tabaci MEAM1 (MEAM1 BtTRP. The full-length cDNA of MEAM1 BtTRP was 3871 bp, and the open reading frames of BtTRP was 3501 bp, encoding 1166 amino acids. Additionally, the BtTRP mRNA expression level was significantly increased at 35°C. Furthermore, compared with control treatments, the survival rate of B. tabaci MEAM1 adults was significantly decreased under high temperature stress conditions after feeding with dsRNA BtTRP. Collectively, these results showed that MEAM1 BtTRP is a key element in sensing high temperature and plays an essential role in B. tabaci MEAM1 heat tolerance ability. Our data improved our understanding of the mechanism of temperature sensation in B. tabaci MEAM1 at the molecular level and could contribute to the understanding of the thermal biology of B. tabaci MEAM1 within the context of global

  4. Pyrosequencing the Bemisia tabaci transcriptome reveals a highly diverse bacterial community and a robust system for insecticide resistance.

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    Wen Xie

    Full Text Available BACKGROUND: Bemisia tabaci (Gennadius is a phloem-feeding insect poised to become one of the major insect pests in open field and greenhouse production systems throughout the world. The high level of resistance to insecticides is a main factor that hinders continued use of insecticides for suppression of B. tabaci. Despite its prevalence, little is known about B. tabaci at the genome level. To fill this gap, an invasive B. tabaci B biotype was subjected to pyrosequencing-based transcriptome analysis to identify genes and gene networks putatively involved in various physiological and toxicological processes. METHODOLOGY AND PRINCIPAL FINDINGS: Using Roche 454 pyrosequencing, 857,205 reads containing approximately 340 megabases were obtained from the B. tabaci transcriptome. De novo assembly generated 178,669 unigenes including 30,980 from insects, 17,881 from bacteria, and 129,808 from the nohit. A total of 50,835 (28.45% unigenes showed similarity to the non-redundant database in GenBank with a cut-off E-value of 10-5. Among them, 40,611 unigenes were assigned to one or more GO terms and 6,917 unigenes were assigned to 288 known pathways. De novo metatranscriptome analysis revealed highly diverse bacterial symbionts in B. tabaci, and demonstrated the host-symbiont cooperation in amino acid production. In-depth transcriptome analysis indentified putative molecular markers, and genes potentially involved in insecticide resistance and nutrient digestion. The utility of this transcriptome was validated by a thiamethoxam resistance study, in which annotated cytochrome P450 genes were significantly overexpressed in the resistant B. tabaci in comparison to its susceptible counterparts. CONCLUSIONS: This transcriptome/metatranscriptome analysis sheds light on the molecular understanding of symbiosis and insecticide resistance in an agriculturally important phloem-feeding insect pest, and lays the foundation for future functional genomics research of the

  5. A construção do domínio etnozoológico “inseto” pelos moradores do povoado de Pedra Branca, Santa Terezinha, Estado da Bahia - DOI: 10.4025/actascibiolsci.v26i1.1662 The construction of the ethnozoological dominion “insect” by the inhabitants of the village of Pedra Branca, Santa Terezinha, Bahia state, Brazil - DOI: 10.4025/actascibiolsci.v26i1.1662

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    Eraldo Medeiros Costa Neto

    2004-04-01

    Full Text Available Discute-se a percepção e a construção do domínio etnozoológico “inseto” por moradores do povoado de Pedra Branca, município de Santa Terezinha, localizado na região centro-oeste do Estado da Bahia. Dados foram obtidos de fevereiro a maio de 2001, realizando-se entrevistas abertas, semi-estruturadas e observações comportamentais com 74 homens e 79 mulheres, cujas idades variaram de 4 a 108 anos. Registrou-se que o termo “inseto” é utilizado como uma categoria etnotaxonômica ampla que reúne diferentes organismos não sistematicamente relacionados (rato, cobra, lagartixa, etc., além dos insetos lineanos. Com base nas informações registradas no povoado e em dados da literatura, pode-se levantar a suposição de que o domínio “inseto” ocorre como um padrão nos sistemas de classificação etnobiológicos. Sugere-se que um processo de aprendizagem baseado em estímulos sensoriais adequados poderia levar a mudanças de atitudes dos indivíduos com relação aos insetos, tornando-os mais toleráveis ao convívio com esses organismosThis article discusses the perception and the construction of the ethnozoological dominion “insect” by the inhabitants of Pedra Branca village, Santa Terezinha, central-west region of Bahia. Data were obtained from February to May 2001 through open and semi-structured interviews, and also by observations of behaviors of 74 males and 79 females, from 4 to 108 years old. It was noted that the linguistic label “insect” is used as a broad ethnotaxonomic category that brings together different organisms not systematically related (rat, snake, lizard, etc., besides the Linnean insects. According to the data recorded both in this village and from the literature, it could be hypothesized that the dominion “insect” occurs as a pattern in the ethnobiological classification systems. An apprenticeship process based on suitable sensorial stimulus could lead people change their attitudes toward

  6. Desarrollo de herramientas moleculares para la evaluación de la calidad genética y productividad en la cría artificial de Diachasmimorpha longicaudata, agente de control biológico de moscas plaga de los frutos

    OpenAIRE

    2016-01-01

    Diachasmimorpha longicaudata Ashmead (Hymenoptera: Braconidae) es un endoparasitoide solitario de estadios larvales de moscas de la fruta perteneciente a la familia Tephritidae. Es criado a nivel masivo en bioplantas y utilizado en diversas partes del mundo para las estrategias de control biológico (CB) principalmente de dípteros de importancia económica de los géneros Ceratitis, Anastrepha y Bactrocera. Actualmente, se estudia su implementación en nuestro país para el control de Ceratitis ca...

  7. Reconocimiento de parasitoides y evaluación de un cebo tóxico para el control de las moscas del botón floral dasiops spp. (diptera: lonchaeidae) del maracuyá amarillo y la pitaya amarilla en el Valle del Cauca

    OpenAIRE

    Quintero Quintero, Edgar Mauricio

    2013-01-01

    Actualmente, el control de las moscas de los botones florales del maracuyá amarillo Dasiops inedulis Steyskal y de la pitaya amarilla, D. saltans Townsend (Diptera: Lonchaeidae), se basa en aplicaciones de insecticidas de amplio espectro que contaminan el medio ambiente y afectan negativamente la entomofauna benéfica (p.ej., enemigos naturales y polinizadores). Los objetivos principales de este estudio fueron la evaluación de un cebo tóxico de origen natural y la búsqueda de parasitoides para...

  8. Biodiversidade de moscas-das-frutas (Diptera, Tephritoidea) em matas nativas e pomares domésticos de dois municípios do Estado do Tocantins, Brasil Biodiversity of fruit flies (Diptera, Tephritoidea) in native forests and orchards in two counties of the State of Tocantins, Brazil

    OpenAIRE

    Darcy A. do Bomfim; Manoel A. Uchôa-Fernandes; Marcos A. L. Bragança

    2007-01-01

    Este trabalho apresenta análise faunística comparativa das espécies de moscas-das-frutas capturadas em armadilhas McPhail (junho a dezembro de 2002) com proteína hidrolisada de milho a 5%. Foram comparadas a riqueza de espécies e a estrutura populacional entre ambientes de mata e pomar dos municípios de Palmas e Porto Nacional, TO. Foram capturados 1.748 indivíduos de espécies de três gêneros de Tephritidae: Tomoplagia Coquillett, 1910, Anastrepha Schiner, 1868 e Ceratitis MacLeay, 1829. De L...

  9. Knockdown resistance in pyrethroid-resistant horn fly (Diptera: Muscidae populations in Brazil Resistência Knockdown em populações de mosca-dos-chifres do Brasil resistentes aos piretróides

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    Gustavo A. Sabatini

    2009-09-01

    Full Text Available To investigate the kdr (knockdown resistance resistance-associated gene mutation and determine its frequency in pyrethroid-resistant horn fly (Haematobia irritans populations, a total of 1,804 horn flies of 37 different populations from all Brazilian regions (North, Northeast, Central-West, Southeast, and South were molecular screened through polymerase chain reaction (PCR. The kdr gene was not detected in 87.08% of the flies. However, the gene was amplified in 12.92% of the flies, of which 11.70% were resistant heterozygous and 1.22% were resistant homozygous. Deviation from Hardy-Weinberg equilibrium (HWE was found only in 1 ranch with an excess of heterozygous. When populations were grouped by region, three metapopulations showed significant deviations of HWE (Central-West population, South population and Southeast population. This indicates that populations are isolated one from another and kdr occurrence seems to be an independent effect probably reflecting the insecticide strategy used by each ranch. Although resistance to pyrethroids is disseminated throughout Brazil, only 48% of resistant populations had kdr flies, and the frequency of kdr individuals in each of these resistant populations was quite low. But this study shows that, with the apparent exception of the Northeast region, the kdr mechanism associated with pyrethroid resistance occurs all over Brazil.Com o objetivo de verificar a ocorrência e determinar a frequência da mutação kdr (knock down resistance em populações de Haematobia irritans (mosca-dos-chifres resistentes aos piretróides, foram analisados 1.804 indivíduos de 37 populações de todas as Regiões do Brasil. Com exceção da Região Nordeste, o kdr (knock down resistance gene foi encontrado em populações de todas as regiões. A mutação não foi detectada em 87,08% dos indivíduos. Entretanto, o gene foi amplificado de 12,92% das moscas, das quais 11,70% se mostraram heterozigotas resistentes e 1

  10. Parasitismo natural em moscas-das-frutas (Diptera: Tephritidae no semiárido do sudoeste da Bahia, Brasil Natural parasitism in fruit-flies in the fruticulture area of anagé, semi-arid of southwestern Bahia, Brazil

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    Ricardo Falcão de Sá

    2012-12-01

    Full Text Available Parasitoides são importantes agentes de controle natural de tefritídeos, e os conhecimentos sobre as relações tritróficas podem subsidiar o manejo destas pragas. Este trabalho objetivou estimar índices de parasitismo em moscas-das-frutas, em 21 espécies vegetais, e identificar as espécies de parasitoides associados, nas condições do semiárido do sudoeste da Bahia. Oito hospedeiros apresentaram infestação por Anastrepha spp. e, destes, em quatro, ocorreu parasitismo superior a 20,0%, sendo: 20,8% (Ziziphus joazeiro L.; 21,3% (Spondias tuberosa L.; 32,4% (Spondias purpurea L. e 57,1% (Malpighia emarginata L.. Os parasitoides coletados pertencem à família Braconidae, sendo 89% de Doryctobracon areolatus e 11% de Asobara anastrephae.Parasitoids are important natural control agents of tephritids and knowledge about the tritrophic relationships can support the management of these pests. This study aimed to estimate of parasitism indexes in fruit flies in 21 plant species and identify the species of parasitoids associated, in semiarid conditions of Southwestern Bahia. Eight hosts showed infestation by Anastrepha spp. and, of these, four occurred parasitism above 20.0%, of which: 20.8% (Ziziphus joazeiro L.; 21.3% (Spondias tuberosa L.; 32.4% (Spondias purpurea L. and 57.1% (Malpighia emarginata L.. The collected parasitoids belong to the Braconidae family, 89% of Doryctobracon areolatus and 11% of Asobara anastrephae.

  11. 烟粉虱成虫空间分布型的研究%The spatial distribution pattern of Bemisia tabaci adults

    Institute of Scientific and Technical Information of China (English)

    沈斌斌; 任顺祥; P.D.Musa; 周建华

    2005-01-01

    对烟粉虱Bemisia tabaci成虫在单株茄子(Solanum melongena L.)、西瓜(Citrullus vulgaris Schard)和甜瓜(Cucumis melo L.)上的分布规律及其空间分布型进行了研究.在植株上中部较幼嫩且已充分展开之叶片上烟粉虱成虫数量最多,成虫呈聚集分布.成虫在黄瓜(Cucumis sativus L.)上亦呈聚集分布,确定了不同虫口密度情况下的最适抽样数.

  12. Effect of silver reflective mulch and a summer squash trap crop on densities of immature Bemisia argentifolii (Homoptera: Aleyrodidae) on organic bean.

    Science.gov (United States)

    Smith, H A; Koenig, R L; McAuslane, H J; McSorley, R

    2000-06-01

    Polyethylene mulch with a reflective silver stripe and a yellow summer squash, Cucurbita pepo L., trap crop were tested alone and in combination as tactics to reduce densities of Bemisia argentifolii Bellows & Perring eggs and nymphs, and incidence of bean golden mosaic geminivirus on snap bean, Phaseolus vulgaris L. Egg densities were consistently higher on squash than on bean, but egg densities and virus incidence were not lower on bean grown with squash than on bean grown in monoculture. Silver reflective mulch reduced egg densities compared with bean grown on bare ground during the first week after crop emergence for 2 of the 3 yr that the study was conducted. However, egg suppression by silver mulch was not enhanced by the presence of a squash trap crop when both tactics were combined. The obstacles to suppressing B. argentifolii through the use of trap crops are discussed.

  13. A study of the super-abundant Bemisia tabaci (Gennadius) species complex (Hemiptera: Aleyrodidae) in cassava Mosaic disease pandemic areas in Tanzania

    DEFF Research Database (Denmark)

    Tajebe, Lensa Sefera

    and forcing some farmers to abandon the cultivation of the crop. The severe CMD pandemic is mainly characterized by high severity and incidence of the disease dominated by whitefly-borne infection and super-abundant populations of B. tabaci. All Bemisia tabaci individuals harbour a primary bacterial symbiont...... (Portiera aleyrodidarum) essential for their survival, and many also harbour non-essential secondary symbionts. In an attempt to understand the cause of the super-abundant populations, it was suggested that a distinct genotype cluster is associated with the pandemic, however, there was no definitive proof...... for this or other potential causes of super-abundance. Moreover, these super-abundant populations, that occur in pandemic areas, remain unstudied in terms of the endosymbiotic bacteria they harbour, their population structure, and the potential for gene flow and hybridization. Therefore, this research through...

  14. Genetic mutations associated with chemical resistance in the cytochrome P450 genes of invasive and native Bemisia tabaci (Hemiptera: Aleyrodidae) populations in China

    Institute of Scientific and Technical Information of China (English)

    Bao-Li Qiu; Li Liu; Xiao-Xi Li; Vartika Mathur; Zhen-Qiang Qin; Shun-Xiang Ren

    2009-01-01

    Bemisia tabaci (Gennadius) is a species complex, and its two most damaging biotypes B and Q are globally distributed pests. Despite increasing biological and economic impacts, little is known about the evolutionary mechanisms that favor their competfion with native populations. Here, we investigated the genetic mutations in the P450 gene of the invasive B, Q biotypes and the native Cv population. Four mutations associated with chemical resistance, Pro-Leu, Ala-Ser, Ser-Phe and Trp-Leu, were found in the cytochrome P450 CYP6C and CYP9F genes of the B and Q biotypes. Bioassay results also revealed that both the B and Q biotypes have about 12-47 times more resistance to acephate, betacypermethrin, methomyl, and 5-7 times more resistance to imidacloprid insecticide than Cv population. Our results provide a molecular approach for better understanding and monitoring the pesticide resistances of invasive and native B. tabaci populations in China.

  15. Further compatibility tests of the entomopathogenic fungus Lecanicillium muscarium with conventional insecticide products for control of sweetpotato whitefly, Bemisia tabaci on poinsettia plants

    Institute of Scientific and Technical Information of China (English)

    Andrew G. S. Cuthbertson; Lisa F. Blackburn; Phil Northing; Weiqi Luo; Raymond J. C. Cannon; Keith F. A. Waiters

    2008-01-01

    The effect on spore germination of the entomopathogenic fungus Lecanicillium muscarium following direct exposure for 24 h to the insecticides Majestik, Spray Oil, Agri50E, Savona and Oberon for the control of both egg and second instar stages of the sweetpotato whitefly, Bemisia tabaci, was determined. Exposure to both Agri-50E and Oberon was followed by acceptable spore germination. Infectivity rates of L. rnuscarium on poinsettia foliage in the presence of dry residues of the insecticides were also investigated.No significant detrimental effects on the levels of control of B. tabaci were recorded compared with fungus applied to residue-free foliage. Sequential application of the chemicals Savona, Spray Oil and Majestik with the fungus all produced mortalities of second instar B. tabaci above 90%. Incorporation of these chemicals with L. muscarium into integrated control programs for B. tabaci is discussed.

  16. Whitefly (Bemisia tabaci Genn. , Stern. : Aleyrodidae) infestation patterns as influenced by cotton, weather and Heliothis: hypotheses testing by using simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Baumgaertner, J.; Delucchi, V.; Von Arx, R.; Rubli, D.

    1986-01-01

    The whitefly Bemisia tabaci Genn. is an important pest on cotton in the Sudan Gezira. A population model based on the age-specific and time-varying life table approach has been constructed and validated for B. tabaci and the cotton variety Barac. Simulation experiments indicate that weather conditions are favourable for whitefly development until late autumn, when the bolls of early sown Barac open. Host plant quality, as measured by leaf age structure, is a very important factor in the B. tabaci life system. Reduced photosynthesis decreases and delays yield formation, but appears to have little effect on whitefly infestation levels at the time the bolls open. Simulated damage caused by Heliothis larvae to fruiting structures alters the growth of the plants, changes the age structures of the leaves and suggests increased whitefly numbers at the time of boll opening. 27 refs., 6 figs.

  17. INFESTAÇÃO DE MOSCAS-DAS-FRUTAS EM VARIEDADES DE MANGA (Mangifera indica L. NO ESTADO DE GOIÁS INFESTATION OF FRUIT FLY IN VARIETIES OF MANGO IN THE STATE OF GOIÁS

    Directory of Open Access Journals (Sweden)

    Juracy Rocha Braga Filho

    2007-09-01

    Full Text Available

    A mangueira (Mangifera indica L. é a principal espécie frutífera da família Anacardiaceae cultivada no Brasil. A expansão dessa cultura nos últimos anos, tanto para o consumo in natura como para a exportação, é limitada por diversas pragas, principalmente pelas moscas-das-frutas. No período de setembro de 1999 a fevereiro de 2000 foi estudado o nível de infestação natural de moscas-das-frutas em dez variedades de manga, em três municípios do Estado de Goiás. Foram obtidos 1.195 pupários, dos quais emergiram 484 adultos de Anastrepha (80% dos insetos identificados, 104 lonqueídeos (17,2 % e 17 braconídeos (2,8%. Das fêmeas identificadas, 77,9% pertenciam ao gênero Anastrepha e 22,08%, a Neosilba. As espécies identificadas foram: A. obliqua (48,78%, A. fraterculus (47,97%, A. sororcula (2,03% e A. turpiniae (1,22%, referida pela primeira vez em frutos de manga no Estado. O parasitóide Doryctobracon areolatus foi encontrado em larvas/pupas de moscas-das-frutas, nas variedades Imperial e Tommy Atkins. As variedades com maiores índices de infestação foram Imperial (15,3 pupários/fruto e 73,611 pupários/kg de frutos, em Goiânia, e Tommy Atkins (7,0 pupários/fruto e 17,503 pupários/kg de frutos, no município de Orizona. Em Goiânia, a variedade Bourbon não foi infestada, e a Sabina apresentou um índice de infestação de 0,076 pupários/fruto e 0,363 pupários/ kg de frutos.

    PALAVRAS-CHAVE: Insecta; Diptera; Tephritoidea; avaliação de danos; parasitóides.

    Mango (Mangifera indica L. production has expanded greatly in Brazil but several pests, especially fruit flies, have limited both fresh fruit consumption and

  18. Response of the polyphagous whitefly Bemisia tabaci B-biotype (Hemiptera: Aleyrodidae) to crop diversification - influence of multiple sensory stimuli on activity and fecundity.

    Science.gov (United States)

    Bird, T L; Krüger, K

    2006-02-01

    A fundamental question concerning crop diversification is which mechanisms determine pest population size in polycultures compared to monocultures. It has been proposed that polyphagous insects experience a difficulty in decision-making when selecting food and oviposition sites in the presence of different host plants. This hypothesis was tested in the extremely polyphagous whitefly Bemisia tabaci (Gennadius) B-biotype, where behaviour (movement) and fecundity of females were compared in choice and no-choice experiments in the laboratory. Two parallel tests, one on different crops, including cucumber, bean and tomato, and one on different tomato cultivars, were conducted using both a mixture of crops and of tomato cultivars, as opposed to the same crop or cultivar respectively. Bemisia tabaci showed a distinct behavioural preference for cucumber when exposed to different crops simultaneously suggesting that B. tabaci has no difficulty in choosing a host plant, i.e. in making a decision, when one of the plants offered in the choice test is a high-ranking host plant. Conversely, when only low-ranking hosts of similar, but not identical, signatures were present, female whiteflies appeared to have difficulty in making a decision, resulting in increased movement and reduced fecundity. This is consistent with both the hypothesis that polyphagous insects have a problem selecting a host plant when given multiple choices and with the hierarchy threshold model, under which egg loads are lessened between periods of searching for better host plants. The study illustrates how insect behaviour can be affected by inter-cropping not only with different crops, but also with different cultivars of the same crop, thus potentially providing a simple and efficient way of reducing whitefly population build-up.

  19. 10种杀虫剂对南京地区Q型烟粉虱的室内毒力测定%Indoor Toxicities of Ten Insecticides to Q -type Bemisia tabaci in Nanjing District

    Institute of Scientific and Technical Information of China (English)

    徐德进; 季英华; 顾中言; 徐广春; 许小龙; 董玉轩

    2011-01-01

    在室内测定了10种杀虫剂对南京地区Q型烟粉虱的毒力,为生产上科学选择杀虫剂品种提供依据.根据烟粉虱的虫态和虫龄分别设计毒力测定方法,结果表明:10种杀虫剂中阿维菌素、甲氨基阿维菌素苯甲酸盐、啶虫脒和印楝素对烟粉虱成虫、若虫毒力较高,测定的杀虫剂品种中仅印楝素和噻虫啉对烟粉虱卵表现出较好的杀伤作用;在南京地区防治烟粉虱时应选用敏感性高的抗生素类杀虫剂,交替使用新烟碱类农药,并配合使用对烟粉虱卵高效的杀虫剂品种.%In order to scientifically apply insecticides to control Q -type Bemisia tabaci in the production in Nanjing, the toxici-ties of ten insecticides to Q -type Bemisia tabaci in Nanjing district were tested in the laboratory, and different determination methods were designed according to the morphology and instar of Bemisia tabaci. The results indicated that the toxicities of Abamectin, Em-amectin benzoate, Acetamiprid and Azadirachtin to the adult and nymph were higher than those of the other insecticides tested in the experiments. Among the ten insecticides, only Azadirachtin and Thiacloprid exhibited high ovicidalactivity. Therefore, the application of the antibiotic insecticides with high sensitivity, the alternative use of the neonicotinoid pesticides, and the combined application of the insecticides with high ovicidalactivity were recommended in the control of Bemisia tabaci in Nanjing district.

  20. Prospects for area-wide integrated control of tsetse flies (Diptera:Glossinidae and trypanosomosis in sub-Saharan Africa Perspectivas para el control integrado abarcativo del área de moscas tse-tsé (Diptera: Glossinidae y la tripanosomiasis en el África sub-Sahariana

    Directory of Open Access Journals (Sweden)

    Marc J.B. Vreysen

    2006-07-01

    large scale eradication approaches to localised tsetse control efforts by the local farmer communities, combined with the growing economic crises and political instability in many African countries has most likely contributed to the decline of most tsetse control efforts in the last decades. It is obvious that the sustained removal of the tsetse fly over large geographical areas would result in enormous benefits for the rural farmer community. Tsetse population genetic studies and data derived from satellite remote sensing are providing more and more convincing evidence that tsetse fly populations are not distributed in a continuous belt (at least in East Africa, but in large fragmented pockets. These tsetse 'islands ' (e.g. the Southern Rift Valley in Ethiopia, KwaZulu Natal in South Africa-Mozambique and the Niayes area in West Senegal offer excellent opportunities for the creation of sustainable tsetse-free zones using an AW-IPM approach.Los países del África sub-Sahariana están entre los menos desarrollados del mundo, y el hambre y la pobreza continúan siendo muy extendidos en la mayoría de las comunidades rurales. Se considera que disminuir el hambre y la sub-alimentación mediante la introducción de ganado productivo, como fuente de tracción y abono para la producción agrícola, el transporte, los lácteos y la carne, es un primer paso fundamental hacia un mejor desarrollo rural. La presencia de la mosca tse-tsé en un tercio del continente africano y la tripanosomiasis que transmite, se consideran la principal barrera para el desarrollo del ganado productivo. A pesar de la administración anual de 35 millones de dosis de drogas tripanocidas (a 1 (un dólar por dosis, los granjeros africanos pierden 3 millones de cabezas de ganado por año debido a esta enfermedad, y las pérdidas económicas directas se estiman entre 600 y 1200 millones de dólares. La mosca tse-tsé afecta principalmente a los campesinos pobres, y es considerada una causa fundamental de

  1. Ação do anidrido naftálico na seletividade de herbicidas aplicados para controle de azevém em aveia-branca Action of naphthalic anhydride on herbicide selected for ryegrass control in oat

    Directory of Open Access Journals (Sweden)

    M.A. Rizzardi

    2001-12-01

    Full Text Available Um experimento foi conduzido em Passo Fundo-RS, com o objetivo de avaliar os efeitos do tratamento de sementes de aveia-branca (Avena sativa com o antídoto anidrido naftálico (AN na seletividade de herbicidas utilizados para controle de azevém (Lolium multiflorum. O delineamento experimental utilizado foi em parcelas subdivididas, em blocos casualizados, repetidos quatro vezes. As parcelas principais foram constituídas pela ausência ou presença do AN (5 g kg-1 no tratamento das sementes de aveia, e nas subparcelas foram alocados cinco tratamentos herbicidas, uma testemunha sem azevém e sem aplicação de herbicida e uma testemunha sem controle de azevém. Os tratamentos herbicidas utilizados foram diclofop (284 e 426 g ha-1, sulfentrazone (600 g ha-1, isoxaflutole (52,5 g ha-1 e clomazone (1.000 g ha-1. Foram avaliados o percentual de controle de azevém, a fitotoxicidade visual dos herbicidas e as características associadas à cultura da aveia, como massa seca da parte aérea, altura de planta, número de plantas e de panículas por área, peso de 1.000 grãos e rendimento de grãos. Os resultados evidenciaram que o tratamento de sementes de aveia com AN não aumentou a seletividade dos herbicidas aplicados, com exceção para massa seca da parte aérea, no caso de sulfentrazone. Os herbicidas que propiciaram os melhores níveis de controle de azevém foram os que ocasionaram maiores danos fitotóxicos à cultura da aveia-branca.An experiment was conducted in Passo Fundo, Rio Grande do Sul, Brazil, to evaluate the effects of treatment of oat seeds (Avena sativa with naphthalic anhydride safener (AN on the herbicide selectivity used for ryegrass (Lolium multiflorum control. The experimental design used was a split-plot one, in randomized blocks, with four replications. The treatments consisted of oat seed treated or not with AN (5 g kg-1 seed as main plots, and of five herbicide treatments, one check without ryegrass and herbicide and

  2. Análise Preliminar de Novos Afloramentos da Formação Jandaíra (Cretáceo Superior- Bacia Potiguar no Município de Areia Branca, Rio Grande do Norte.

    Directory of Open Access Journals (Sweden)

    Natália Benaim

    2007-07-01

    Full Text Available Em março de 2006 ocorreu uma expediçãoà Bacia Potiguar, com o objetivo de coletar fósseisda Formação Jandaíra. A expedição chegou a regiãode Areia Branca nas coordenadas 05° 08’ 70” S / 37º10’ 26” W onde há afloramentos representados porseqüências de calcários intercalados com sedimentosargilosos, depositados formando uma plataformacarbonática. Estes afloramentos aqui denominadosAB01 e AB02 foram expostos pela ação da pedreiraBrasil Química, formando paredes de aproximadamente8 m de altura e apresentaram diversidadede macrofósseis de moluscos com representantes debiválvios, gastrópodes e cefalópodes, assim como apresença de equinodermos, crustáceos e icnofósseis.O município de Areia Branca situa-se na mesorregiãoOeste Potiguar e na microrregião Mossoró, limitando-se com os municípios de Serra do Mel, Porto doMangue, Grossos, Mossoró e o Oceano Atlântico,abrangendo uma área de 373 km², encontra-se inserido,geologicamente, na Província Borborema, sendoconstituído pelos sedimentos da Formação Jandaíra,do Grupo Barreiras e pelos depósitos Colúvio-eluviais,Aluvionares e Litorâneos. Os dois afloramentossão parte de um mesmo paleoambiente pertencenteà Formação Jandaíra, com variação mínimaentre as faunas presentes. No afloramento AB01foram identificados 30 exemplares dentre eles os biválviosInoceramus baixaverdensis, Inoceramus sp.,Ostrea mossoroensis, Pholadomya sp., Lima sp.; osgastrópodes Tylostoma brasilianum, Tylostoma sp.,e um exemplar ainda não identificado; os equinodermasPhymosoma riograndensis, Hemiaster rioupanemensis;além do contramolde de cefalópodeamonóide Pachydiscus sp.. Em AB02 dos 28 exemplaresidentificados, foram encontradas camadascom Ostrea mossoroensis; fragmentos de inoceramídeos,dois biválvios e um gastrópode mal preservadosque dificultaram sua identificação; o gastrópodeAporrhais sp., além do biválvio Pholadomya sp.,os gastrópodes Tylostoma brasilianum

  3. Emprego da poda verde para a obtenção de duas safras por ciclo vegetativo em 'Niagara Branca' Green pruning to obtain two harvests by vegetative cicle on Niagara grapevine

    Directory of Open Access Journals (Sweden)

    Paulo Vitor Dutra de Souza

    2007-01-01

    Full Text Available Avaliou-se o efeito de épocas de poda verde em dois anos consecutivos visando obter a segunda safra de uva em um mesmo ciclo vegetativo na cv. Niágara Branca (Vitis labrusca L., cultivada no sistema em espaldeira. O experimento foi realizado na Estação Experimental Agronômica da UFRGS, em Eldorado do Sul (RS, nas safras de 2003/2004 e 2004/2005. Os tratamentos constaram de três épocas de poda verde, realizadas imediatamente após a quarta folha acima do último cacho, e dois anos consecutivos de avaliação. Todas as plantas foram submetidas à superação de dormência mediante aplicação de cianamida hidrogenada a 2%. Analisou-se a duração dos estádios fenológicos, o período de maturação, a produção por planta, a massa fresca do cacho, o teor de sólidos solúveis totais e a acidez total titulável. Observou-se que a época de realização da poda verde não afetou a quantidade, nem a qualidade da uva produzida na primeira colheita, apenas atrasando-a em uma semana. A poda verde realizada no início de novembro possibilitou a segunda colheita de uva, realizada entre março e abril, sendo uma alternativa de ampliação do período de oferta do produto no mercado.The aim of this study was to evaluate the effects of green prunings on two consecutive years to obtain a second harvest of 'Niagara Branca' (Vitis labrusca grapevine in the same season. The experiment was carried out at Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, located at Eldorado do Sul, State of Rio Grande do Sul, Brazil in 2003/2004 and 2004/2005 growth seasons. The grapevines were conducted by cordon training. The treatments involved three dates of green pruning, performed at fourth leaf situated above the last grape, and two seasons. All the plants were sprayed with hidrogenate cianamide (2% to overcome dormency. Fenology, plant production, weight of grapes, °Brix and titratable acid were evaluated. The green pruning time

  4. Presença do vírus da síndrome da mancha branca em crustáceos decápodes silvestres em lagoas costeiras no Sul do Brasil

    Directory of Open Access Journals (Sweden)

    S.W. Costa

    2012-02-01

    Full Text Available A presença do vírus da síndrome da mancha branca (em inglês WSSV nas principais espécies de camarões, siris e caranguejos de cinco lagoas que recebem o efluente de fazendas afetadas pela enfermidade foi detectada por nested PCR, e inclusões virais nos camarões por histologia. Pela nested PCR encontrou-se a presença de WSSV em 13 de 16 (81,2% amostras de camarões da espécie Farfantepenaeus paulensis, em 13 de 14 (92,8% de Litopenaeus schmitti, em uma de duas de Farfantepenaeus brasiliensis (50%, em 13 de 15 (86,6% de siri da espécie Callinectes danae e em 11 de 12 (91,6% de Callinectes sapidus, e não foi detectada no caranguejo Chasmagnathus granulata em 10 amostras. Inclusões características de WSSV foram observadas em três amostras histológicas de 50 (6,0% no epitélio gástrico e cuticular e nas brânquias de dois exemplares de F. paulensis e um de L. schmitti. É o primeiro relato da presença de WSSV em camarões L. schmitti e no siri C. danae silvestres. As principais espécies de camarões e siris dos ambientes de entorno das fazendas foram contaminadas pelo WSSV, constituindo-se em vetores potenciais do vírus.

  5. Resistência cruzada da losna-branca (Parthenium hysterophorus aos herbicidas inibidores da enzima acetolactato sintase Ragweed parthenium (Parthenium hysterophorus cross-resistance to acetolactate synthase inhibiting herbicides

    Directory of Open Access Journals (Sweden)

    D.L.P. Gazziero

    2006-01-01

    Full Text Available A aplicação de um mesmo herbicida, ou de herbicidas com o mesmo mecanismo de ação, durante anos consecutivos, numa mesma área, pode resultar na seleção de biótipos de plantas daninhas resistentes a herbicidas. O objetivo deste trabalho foi confirmar a resistência de um biótipo da planta daninha losna-branca (Parthenium hysterophorus aos herbicidas inibidores da enzima acetolactato sintase (ALS, proveniente de uma propriedade rural no município de Mandaguari, norte do Estado do Paraná. Plantas com suspeita de resistência foram tratadas com diversos herbicidas e doses e comparadas com plantas de uma população suscetível. Os tratamentos foram as doses recomendadas dos herbicidas, duas e quatro vezes superiores à dose recomendada. Os produtos e as doses aplicadas foram cloransulam-methyl a 0,0; 33,6; 67,2; e 134,4 g i.a. ha-1 mais o adjuvante Agral a 0,2% v/v, chlorimuron-ethyl a 0,0; 20,0; 40,0; e 80,0 g i.a. ha-1, imazethapyr a 0,0; 100,0; 200,0; e 400,0 g i.a. ha-1 e iodosulfuron-methyl-sodium mais foramsulfuron a 0,0; 3,0 + 45,0 g i.a. ha-1 (150,0 g p.c. ha¹; 6,0 + 90,0 g i.a. ha-1 (300,0 g p.c. ha-1; e 12,0 + 180,0 g i.a. ha-1 (600,0 g p.c. ha-1. Foi acres centado um tratamento com o herbicida 2,4-D na dose de 536,0 g e.a. ha-1. As curvas de doseresposta do biótipo resistente foram inferiores às do biótipo suscetível em todas as doses e herbicidas estudados. O biótipo de losna-branca foi confirmado como resistente aos herbicidas inibidores da ALS. A ocorrência de resistência cruzada foi observada em relação aos herbicidas pertencentes aos grupos químicos das imidazolinonas (imazethapyr, triazolopirimidinas (cloransulam-methyl e sulfoniluréias (chlorimuron-ethyl e iodosulfuron-methyl-sodium mais foramsulfuron. O herbicida 2,4-D, apresentou alto índice de controle de ambos os biótipos de losna-branca avaliados, confirmando que esse mecanismo de ação do herbicida é uma importante alternativa para manejar

  6. Controle de mosca doméstica em área de disposição de resíduos sólidos no Brasil House fly control in solid waste disposal area in Brazil

    Directory of Open Access Journals (Sweden)

    Adair Ferreira Motta Teixeira

    2008-12-01

    Full Text Available Desenvolveu-se uma metodologia de controle de Musca domestica (L. em áreas de disposição de resíduos sólidos. Dois mosquicidas à base de azametifós foram aplicados em diferentes superfícies: nas verticais, a formulação pó molhável foi aplicada com rolos de pintura e, através de pulverização, na superfície de leiras; nas horizontais, foi empregado o mosquicida na formulação granulada. O nível de infestação de moscas foi avaliado por meio do monitoramento em placas (Scudder Fly Grill. Nas áreas das leiras, reduções de 98,5% e 100% foram atingidas em 18 e 30 dias, respectivamente, após a aplicação do produto. Na estação de transferência do lixo, observaram-se reduções de 85,6% e 98,7% no mesmo período de tempo. A aplicação de azametifós em diferentes formulações mostrou ser eficiente no controle da Musca domestica por um período de 30 dias.A Musca domestica (L. control method in solid waste disposal areas was developed. Two fly control products based on azamethiphos were applied to different surfaces: on vertical surfaces, the wettable powder was used as spray or paint-on and on windrows, as spray; on horizontal surfaces granular bait was used. Fly infestation was evaluated by Scudder Fly Grills. In the windrows areas, reductions of 98,5% and 100 % were achieved 18 and 30 days respectively after application. In the waste transfer station 85,6% and 98,7 % reductions were achieved over the same period of time. Application of azamethiphos in different formulations was effective against M. domestica for 30 days.

  7. Effectiveness of Metarhizium anisopliae against immature stages of Anastrepha fraterculus fruitfly (Diptera : Tephritidae Eficácia de Metarhizium anisopliae a estágios imaturos de Anastrepha fraterculus a mosca das frutas (Diptera : Tephritidae

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    Ricardo Henry Rodrigues Destéfano

    2005-03-01

    Full Text Available The study evaluated the effectiveness of Metarhizium anisopliae var. anisopliae (Hyphomycetes : Moniliales strain E9, isolated from the pasture spittlebug Deois flavopicta (Hemiptera : Cercopidae, against larvae, prepupae and pupae stage and emergent adults of Anastrepha fraterculus, the South American fruitfly. The bioassay was carried out simulating field conditions, on autoclaved (AS and non-autoclaved (NAS soil from typical citrus orchards in the State of São Paulo, Southeastern region of Brazil. Various concentrations of conidia were incorporated into the soil the mortality, calculated based on the percentage of adult emergence, was 86% for the highest conidia concentrations: 2.52 x 10(10 for AS and 2.52 x 10(10 for NAS. The lethal concentration (LC50, expressed as conidia concentration, was 8.44 x 10(9 conidia/g of soil (S for AS and 12.23 x 10(9 conidia/g of soil for NAS.O estudo avaliou a eficácia de Metarhizium anisopliae var. anisopliae, (Hyphomycetes : Moniliales linhagem E9, isolada da cigarrinha das pastagens Deois flavopicta (Hemiptera : Cercopidae, contra larvas, prepupas, pupas e adultos emergentes de Anastreha fraterculus, a mosca Sul Americana das frutas. Os bioensaios foram conduzidos simulando condições de campo em solo autoclavado (AS e não autoclavado (NAS de pomares típicos de citros no Estado de São Paulo, sudeste do Brasil. Várias concentrações de conídios foram incorporadas no solo. A mortalidade calculada sobre a porcentagem de adultos emergentes, foi de 86% para as concentrações mais altas de conídios: 2,52 x 10(10 para AS e 2,52 x 10(10 para NAS. A concentração letal (LC50 expressa pela concentração de conídios, foi 8,44 x 10(9 conídios/g de solo para AS e 12,2 x 10(9 conídios/g/S para NAS.

  8. Levantamento de moscas-das-frutas e de seus parasitóides no município de Ferreira Gomes, Estado do Amapá Survey of fruit flies and its parasitoids in Ferreira Gomes, Amapá State

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    Wilson Rodrigues da Silva

    2007-02-01

    Full Text Available Este trabalho objetivou efetuar um levantamento das espécies de moscas-das-frutas e de seus parasitóides, no município de Ferreira Gomes, Estado do Amapá. Entre os meses de março e julho de 2005, foram coletadas 38 amostras de frutos de seis espécies vegetais, totalizando 43,7kg. Foram obtidos 515 pupários, dos quais emergiram 123 adultos da família Tephritidae e 102 parasitóides. Foram obtidas cinco espécies de Anastrepha: A. fraterculus, A. obliqua, A. striata, A. antunesi e A. turpiniae. Os únicos hospedeiros de tefritídeos foram o taperebá (Spondias mombin e a goiaba (Psidium guajava, com índices de infestação natural de 0,51 e 0,24 pupário/fruto e de 52,3 e 5,4 pupários kg-1 de fruto, respectivamente. As espécies dominantes foram A. obliqua, no taperebá, e A. striata, na goiaba. Foram obtidos exemplares de quatro espécies de Braconidae: Doryctobracon areolatus, Utetes anastrephae, Opius bellus e Opius sp., sendo a primeira a mais abundante.This research was aimed at doing a survey on fruit flies and their parasitoids species in Ferreira Gomes, Amapá State, Brazil. Exactly 38 samples of fruits of six vegetables species were collected and it totaled 43,7kg from March to July of 2005. It was possible to obtain 515 puparia that emerged 123 Tephritidae adults and 102 parasitoids. Moreover, five species of Anastrepha were registered: A. fraterculus, A. obliqua, A. striata, A. antunesi and A. turpiniae. Spondias mombin and Psidium guajava were the only hosts of Tephritidae species, they had indices of natural infestation of 0.51 e 0.24 puparia/fruit and 52.3 and 5.4 puparia kg-1, respectively. The dominant species were A. obliqua, in S. mombin, and A. striata, in P. guajava. Four species of Braconidae were registered: Doryctobracon areolatus, Utetes anastrephae, Opius bellus and Opius sp. Of all these species, the first one was the most abundant.

  9. 烟粉虱血细胞对白僵菌的防御反应%Defense Response of Hemolymph in Bemisia tabaci to Beauveria bessiana

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    任洁; 韩雪梅; 刘昭; 雷仲仁

    2013-01-01

    To identify the defense mechanism of Bemisia tabaci hemolymph against Beauveria bassiana,cellular immune responses of the infected 3rd instar nymph was investigated with optics microscope and Giemsa stain.The results showed that the invasion of Beauveria bassiana could bring about changes in the total numbers of host hemocytes.After 36 hours inoculation,the blastospores appeared in B. tabaci and the total numbers of host hemocytes were increased.At the same time, the blastospores were adsorbed to the surface of plamatocyte.60 hours after inoculation,the hyphal bodies were absorbed to the surface of granulocytes.More hyphal bodies were observed to the surface of granulocytes 96 hours after inoculation,and the insect body color had appeared the symptoms of infection,which means that the B. bassiana has broken the defense of B. tabaci.B. tabaci can only inhibit the invasion of B. basiana temporarily.%  为了探讨烟粉虱(Bemisia tabaci)血淋巴对白僵菌(Beauveria bassiana)的防御机制,利用吉姆萨染色法在光学显微镜下观察烟粉虱3龄若虫血细胞感染白僵菌后的免疫反应。结果表明:白僵菌的入侵可导致烟粉虱血细胞数量发生改变。体表接种36 h后,虫体内出现芽生孢子,血细胞数量开始增加,芽生孢子被吸附到浆血细胞表面;接种60 h后菌丝段吸附到粒血细胞表面;接种96 h后粒血细胞表面吸附大量菌丝段,此时昆虫体色已经呈现感染症状,说明真菌已经打破了烟粉虱的防御体系,烟粉虱幼虫血淋巴对白僵菌有短时间抑制。

  10. Tigela, café e xícara: diversidade formal e dinâmicas de consumo na produção das louças brancas da cidade de São Paulo no começo do século XX

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    Rafael de Abreu e Souza

    2012-01-01

    Full Text Available This article aims to present ideas about the forms and volumes of the refined earthenwares produced, and consumed, in São Paulo city, during 1913 and 1937. For such, we analyze the Petybon archaeological collection, recovered from an urban archaeological site at the neighborhood of Lapa, Água Branca/Vila Romana region. We assume that the diversity of the refined earthenwares forms dialogue with the modernity projects thought to São Paulo, and the consumers demand whose many cultural practice