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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Efeito dos óleos essenciais e de seus compostos majoritários sobre parâmetros biológicos, nutricionais e celular de Spodoptera frugiperda (Lepidoptera: Noctuidae) / Effect of essential oils and their major compounds on biological parameters, nutritional and cellular of Spodoptera frugiperda (Lepidoptera: Noctuidae)

CRUZ, Glaucilane dos Santos 26 February 2016 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-08-25T14:50:11Z No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1404639 bytes, checksum: 8592fadc156629fc753774365392d2ce (MD5) / Made available in DSpace on 2016-08-25T14:50:12Z (GMT). No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1404639 bytes, checksum: 8592fadc156629fc753774365392d2ce (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The study had the following objectives: 1. To test the oil action of Eucalyptus staigeriana F., Ocimum gratissimum L. and Foeniculum vulgare Mill. by contact topic at sublethal doses on biological and reproductive parameters of Spodopera Frugiperda (J.E. Smith); 2. To determine the chemical composition and insecticidal activity of the oils of F. vulgare, O. basilicum L., E. staigeriana, Eucalyptus citriodora Hook, O. gratissimum and their major compounds limonene, trans-anethole, citronellal and linalool on mortality of S. frugiperda and 3. To evaluate the effects of compounds limonene, trans-anethole and limonene+trans-anethole on nutrition, reproduction and testicular apoptosis of this pest. The results showed that the oils of E.staigeriana and F.vulgare at LD20 and LD40 interfered on the biology of S. frugiperda. However, O. gratissimum presented a better result, changing many biological and reproductive parameters in all LD. Chromatographic analysis of the oils showed that the most commonly found were limonene, trans-anethole and methyl chavicol. All oils showed an insecticidal activity, but the highest activity was obtained from trans-anethole with an LD50 of 0.027 mg/g insect, obtaining a toxicity ratio of 1194.07, followed of the oils that presented the substance in the constitution. All treatments reduced the amount of lipids, protein, total sugars and glycogen when compared to the control. However, the most significant result was obtained with the association, except that glycogen did not differ between treatments. All treatments reduced the egg number, oviposition period and adult longevity, when compared to the control. There was no change in the pre-oviposition and post-oviposition parameters. The testicles of the treated larvae with the combination of trans-anethole + limonene and isolated limonene showed apoptosis. It was concluded all oils tested and composed of trans-anethole isolated or associated with limonene present promising results in the control of this important pest. / A pesquisa teve os seguintes objetivos: 1. Testar ação dos óleos de Eucalyptus staigeriana F., Ocimum gratissimum L. e Foeniculum vulgare Mill. por contato tópico, em doses subletais, nos parâmetros biológicos e reprodutivos de Spodoptera Frugiperda (JE Smith); 2. Determinar a composição química e atividade inseticida dos óleos de F. vulgare, Ocimum basilicum L., E. staigeriana, Eucalyptus citriodora Hook, O. gratissimum e dos seus compostos majoritários limoneno, trans-anethole, citronelal e linalool sobre S. frugiperda e; 3. Estudar os compostos limoneno, trans-anethole e limoneno+trans-anethole na nutrição, reprodução e apoptose testicular dessa praga. Os resultados desmonstraram que os óleos de E. staigeriana, e F. vulgare nas DL20 e DL40 interferiram na biologia de S. frugiperda. Contudo, o óleo de O. gratissimum apresentou melhor resultado alterando diversos parâmetros biológicos e reprodutivos, em todas as DL’s. A análise cromatográfica dos óleos demonstrou que os compostos mais comuns foram o limoneno, trans-anethole e o methil chavicol. Todos os óleos demonstraram atividade inseticida, sendo a maior obtida com o composto trans-anethole, apresentando DL50 de 0,027 mg/g de inseto, e razão de toxicidade de 1194,07, seguido dos óleos que apresentaram essa substância na sua constituição. Todos os tratamentos reduziram a quantidade de lipídeos, proteínas, açúcares totais e glicogênio quando comparados à testemunha. Entretanto, os resultados mais expressivos foram obtidos com a associação, exceto o de glicogênio que não apresentou diferença entre os tratamentos. Todos os tratamentos reduziram a quantidade de ovos, período de oviposição e longevidade dos adultos de S. frugiperda, em comparação com a testemunha. Não houve alteração nos parâmetros de pré-oviposição e pós-oviposição. Os testículos das lagartas tratadas com a associação do trans-anethole+limoneno e com o limoneno isolado apresentaram apoptose. Conclui-se que todos os óleos testeados e seu constuinte trans-anethole isolado ou associado ao limoneno apresentam-se promissores para o controle de S. frugiperda.
62

Histofisiologia do canal alimentar e hemócitos de Spodoptera frugiperda (J.E. Smith) (Lepidoptera : Noctuidae) tratadas com Nim (Azadirachta indica A.Juss) / Histophysiology of the food channel and hemocytes of Spodoptera frugiperda (J.E. Smith) (Lepidoptera : Noctuidae) treated with neem (Azadirachta indica A.Juss)

CORREIA, Alicely Araújo 01 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-23T13:13:53Z No. of bitstreams: 1 Alicely Araujo Correia.pdf: 1178729 bytes, checksum: 007e1cb0c61d3a8f7fdcf0344b043ecf (MD5) / Made available in DSpace on 2016-11-23T13:13:53Z (GMT). No. of bitstreams: 1 Alicely Araujo Correia.pdf: 1178729 bytes, checksum: 007e1cb0c61d3a8f7fdcf0344b043ecf (MD5) Previous issue date: 2008-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is the main pest of corn crops. The control of S. frugiperda requires various insecticide applications that might result on selection of resistant populations and environmental contamination. A promising alternative toward the control of this pest is the use of vegetal insecticides such as neem, Azadirachta indica A. Juss (Meliaceae). Few data exist related to the immunologic and histophysiologic reactions of S. frugiperda larvae under neem treatment. Thus, the present research had as objectives: (a) to characterize and to quantify the hemocytes of S. frugiperda larvae pre- and post-treatment with concentrations 0.5 and 1.0% of neem (Neemseto®) on the intervals of 48, 96, 144, 192 and 240h; (b) to describe, histologically, the food channel of the larvae; (c) to characterize the effect of the concentrations 0.5 and 1.0% of neem, in the same evaluation intervals after treatment, on the histophysiology of midgut; (d) to quantify the regenerative cells and; (e) to analyze,histochemically, the secretion product of midgut. Six types of hemocytes were identified in the hemolymph of S. frugiperda larvae: Adipohemocytes, Spherulocytes, Granulocytes, Eonocytoids, Plasmatocytes and Prohemocytes. And, the most abundant hemocytes were Granulocytes and Plasmatocytes. The counting of hemocytes showed effects as function of neem concentrations onthe hemocytary dynamics and possivelmente the endocrine events, contributing for mortality and observed morphologic abnormalities. Despite of expressive larval mortality and of effects with neem at concentration 1.0%, both concentrations (0.5 and 1.0%) modified the cellular immunity of the larvae. Histophysiological alterations occurred as function of tested neem concentrations and time after treatment observed as: degeneration of the epithelium and musculature of the midgut, reduction of regenerative cells and the secretory activity of this region, in the two concentrations of neem. These alterations, however, were observed for larvae treated with neem at concentration 1.0% already from 96h after treatment. These results demonstrate the insecticide activity of the commercial formulation neem (Neemseto®) in both tested concentrations, on thehistophysiology of midgut and on the immunologic reactions of S. frugiperda larvae. / Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) é a principal praga da cultura do milho. Seu controle demanda elevado número de aplicações de inseticidas sintéticos, podendo ocasionar seleção de populações resistentes e contaminação ambiental. Uma alternativa promissora para o controle deste inseto é a utilização de substâncias com ação inseticida oriundas de plantas como o nim, Azadirachta indica A. Juss (Meliaceae). Contudo, os aspectos relacionados às reações imunológicas e histofisiológicas de lagartas de S. frugiperda, promovidos pela interação com o nim, ainda são pouco estudados. Assim, a presente pesquisa teve como objetivos: (a) caracterizar e realizar a contagem diferencial dos hemócitos de lagartas de S. frugiperda, antes e após o tratamento com nim (Neemseto®) nas concentrações 0,5 e 1,0%, nos intervalos de 48, 96, 144, 192 e 240h; (b )descrever, histologicamente, o canal alimentar dessas lagartas; (c) caracterizar o efeito das concentrações 0,5 e 1,0% do nim, nos mesmos intervalos deavaliação após tratamento, sobre a histofisiologia do mesêntero; (d) quantificar as células regenerativas e; (e) analisar, histoquimicamente, o produto de secreção do mesêntero. Na hemolinfa das lagartas de S. frugiperda foram identificados seis tipos de hemócitos: Adipohemócitos, Esferulócitos, Granulócitos, Oenocitóides, Plasmatócitos e Prohemócitos, sendoos Granulócitos e Plasmatócitos mais freqüentes. A contagem diferencial dos hemócitos revelou um efeito concentração-dependente do nim, afetando a dinâmica hemocitária e possivelmente os eventos endócrinos, contribuindo para a mortalidade e anormalidades morfológicas observadas. Apesar da mortalidade e dos efeitos ocorrerem de forma mais expressiva no tratamento com nim a 1,0%, ambas as concentrações (0,5 e 1,0%) alteraram a imunidade celular das lagartas. Foram observadas alterações histofisiológicas que variaram de intensidade de acordo com o tempo e as concentrações, tais como: degeneração do epitélio e da musculatura do mesêntero, redução de células regenerativas e da atividade secretora desta região, nas duas concentrações do nim. Porém, estas alterações foram observadas nas lagartas tratadas com nim a 1,0% já a partir de 96h após o tratamento. Esses resultados demonstram a atividade inseticida da formulação comercial de nim(Neemseto) em ambas as concentrações testadas, na histofisiologia do mesêntero e nas reações imunológicas de lagartas de S. frugiperda.
63

Parâmetros imunológicos e morfofisiológicos em Spodoptera frugiperda (J.E. Smith) (Lepidoptera : Noctuidae) e Podisus nigrispinus (Dallas) (Hemiptera : Pentatomidae) expostos a CRY1AC / Immunological parameters and morphophysiological on Spodoptera frugiperda (JE Smith) (Lepidoptera : Noctuidae) and Podisus nigrispinus (Dallas) (Hemiptera : Pentatomidae) exposed to CRY1AC.

CUNHA, Franklin Magliano da 01 February 2011 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-12-01T14:58:58Z No. of bitstreams: 1 Franklin Magliano da Cunha.pdf: 1121804 bytes, checksum: 66cbfdb39feb9b059c8f94887174e30c (MD5) / Made available in DSpace on 2016-12-01T14:58:58Z (GMT). No. of bitstreams: 1 Franklin Magliano da Cunha.pdf: 1121804 bytes, checksum: 66cbfdb39feb9b059c8f94887174e30c (MD5) Previous issue date: 2011-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Despite of the Bt formulation and transgenic Bt plants efficiency against several lepidopteran species, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) exhibits low susceptibility to the majority of them. The reasons to this low susceptibility specifically to toxins Cry1Ac and Cry1Ab are not fully clarified. Also, it is possible that species moderately or not susceptible to Cry1Ac can convey the toxin to the third trophic level. This study investigated response of S. frugiperda related to Bt with three hypotheses about its low suscepbility: regenerative cells from midgut are activated by Cry1Ac protein and renovate the epithelial cells (i) in hemolymph they increase the nitric oxide and phenoloxidases as a toxin response (ii) and the tolerance is associated to the qualitative and quantitative variations from hemocytes. We still tested the hypothesis that S. frugiperda fed with Bt-cotton can induce alterations in the ultrastructure and histochemistry of digestive cells, in humoral parameters, hemogram and ultrastructure of hemocytes of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae), a generalist predator. It was concluded that Cry1Ac in Bt-cotton is not toxic enough to kill the armyworm, but it induce to humoral and cellular alterations as signal of response to xenobiotic. The Cry1Ac toxin ingested by S. frugiperda can expose the third trophic level (P. nigrispinus) and it causes alterations in the distribution of glycogen, lipids and calcium caused by perimicrovillar matrix disorganization. The TEM revealed the presence of spherocrystals that appear to be involved in the defense against the toxin. The humorals parameters and the hemogram of P. nigrispinus are not affected when they are reared with prey S. frugiperda fed daily with leaf Bt-cotton. However it is capable of induces little modifications in granulocytes and plasmocytes. / Apesar da eficiência de formulações Bacillus thuringiensis (Bt) e plantas transgênicas Bt contra vários lepidópteros, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) apresenta baixa suscetibilidade a maioria deles. As razões dessa baixa suscetibilidade especificamente para toxinas Cry1Ac e Cry1Ab não estão totalmente esclarecidas. É possível que espécies moderadamente ou não suscetíveis ao Cry1Ac possam adquirir essa toxina e expô-la ao terceiro nível trófico. Este estudo investigou a resposta de S. frugiperda relacionadas ao Bt baseado em três hipóteses sobre sua baixa suscetibilidade: células regenerativas do intestino médio são ativadas pela toxina Cry1Ac e renovam as células epiteliais (i), na hemolinfa aumentam a produção de óxido nítrico e fenoloxidase como resposta à toxina (ii), e a tolerância está associada a variações qualitativas e quantitativas dos hemócitos. Testamos ainda a hipotese de que o consumo de S. frugiperda alimentadas com algodão Bt pode levar a alterações na ultraestrutura e histoquímica das células digestivas, nos parâmetros humorais, hemograma e ultraestrutura dos hemócitos de Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae). Conclui-se que toxina Cry1Ac no algodão Bt não é suficientemente tóxica para matar as lagartas, mas induz alteração humoral e celular como sinal de resposta a um xenobiótico. A toxina Cry1Ac ingerida por S. frugiperda pode expor o terceiro nível trófico (P. nigrispinus) e ocasionar alterações na distribuição de glicogênio, lipídios e cálcio em decorrência da desorganização da matriz perimicrovilar. O Microscópio Eletrônico de Transmissão (MET) revelou a presença de esferocristais que parecem estar envolvidos na defesa contra toxina. Os parâmetros humorals e o hemograma de P. nigrispinus não são afetados quando são criados com presa S. frugiperda alimentadas diariamente com folhas frescas de algodão Bt. No entanto, é capaz de induzir modificações pequenas em granulócitos e plasmócitos.
64

ProteÃnas do lÃtex de Calotropis procera (Ait.)R.Br. e seus efeitos sobre pragas agrÃcolas. / Proteins from the latex of Calotropis procera (Ait.) R.Br. and their effects against insects.

ClÃverson Diniz Teixeira de Freitas 27 April 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A planta Calotropis procera pertencente à famÃlia Asclepiadaceae à encontrada em vasta extensÃo do Nordeste Brasileiro. à uma planta laticÃfera e sua produÃÃo endÃgena de lÃtex à extraordinÃria. Embora haja na literatura cientÃfica diversas publicaÃÃes que relatam o potencial medicinal de diversas partes da planta, principalmente de seu lÃtex, nÃo hà ainda uma abordagem bioquÃmica e funcional de seu fluido laticÃfero. Esta pesquisa foi desenvolvida no sentido de proceder a um estudo bioquÃmico parcial de atividades endÃgenas da fraÃÃo protÃica majoritÃria do lÃtex e de avaliar seus efeitos inseticidas sobre diferentes modelos de pragas agrÃcolas. A fraÃÃo protÃica majoritÃria do lÃtex foi preparada a partir de um protocolo previamente desenvolvido no laboratÃrio em que sÃo envolvidas etapas de centrifugaÃÃo e diÃlise. A fraÃÃo protÃica isenta de borracha e de molÃculas de baixa massa molecular foi testada para atividades enzimÃticas endÃgenas proteolÃticas, quitinÃsicas e a-amilÃsica e atividades inibitÃrias para proteases e a-amilase. Ensaios enzimÃticos de digestÃo das proteÃnas do lÃtex por extratos digestivos de insetos foram tambÃm realizados. Bioensaios utilizando-se dietas artificiais contendo diferentes proporÃÃes das proteÃnas do lÃtex Ãntegras, digeridas por pronase ou aquecidas a 98 ÂC foram realizados com seis insetos pertencentes a quatro ordens. Nos bioensaios foram avaliados parÃmetros tais como desenvolvimento, sobrevivÃncia, tempo de emergÃncia dos indivÃduos alÃm de ser avaliado o efeito cumulativo de proteÃnas do lÃtex na dieta por sucessivas geraÃÃes. Na fraÃÃo protÃica do lÃtex foram encontradas atividades proteolÃticas do tipo cisteÃnica e serÃnica, alÃm de atividade quitinolÃtica. NÃo foi detectada atividade a-amilÃsica. SoluÃÃes de proteÃnas do lÃtex nÃo exibiram atividade inibitÃria do tipo a-amilÃsica e tripsÃnica ou quimiotripsÃnica. ApÃs tratamento tÃrmico, proteÃnas do lÃtex ainda solÃveis foram capazes de inibir a atividade da papaÃna. Posteriormente esta atividade inibitÃria foi capaz de inibir as atividades proteolÃticas de Callosobruchus maculatus e Dysdercus peruvianus. As proteÃnas do lÃtex foram inseticidas para C. maculatus, Zabrotes subfasciatus, Anticarsia gemmatalis e Ceratitis capitata enquanto que nÃo foram para Spodoptera frugiperda e D. peruvianus. NÃo houve efeito deletÃrio acumulativo em insetos submetidos a uma dieta contendo proteÃnas do lÃtex durante seis geraÃÃes. Quando digeridas por pronase e aquecidas por 30 min a 98 ÂC, a aÃÃo inseticida das proteÃnas do lÃtex ainda foi mantida sobre o C. maculatus. As proteÃnas do lÃtex foram completamente resistentes à proteÃlise por enzimas digestivas de Dysdercus peruvianus e Callosobruchus maculatus. Entretanto, a aÃÃo proteolÃtica endÃgena do lÃtex promoveu a proteÃlise do extrato enzimÃtico de C. maculatus embora isto nÃo tenha ocorrido no extrato intestinal de D. peruvianus. O lÃtex de C. procera apresenta forte atividade proteolÃtica e resistÃncia à proteÃlise por enzimas digestivas de insetos. Atividade quitinolÃtica foi tambÃm observada. O lÃtex possui atividade inseticida para diferentes pragas agrÃcolas e esta atividade parece estar associada à presenÃa de um inibidor de atividade proteolÃtica do tipo cisteÃnica, alÃm da presenÃa de quitinases e elevada atividade proteolÃtica endÃgena. Assim, a fraÃÃo protÃica do lÃtex pode ser considera como parte constituinte da defesa da planta contra insetos. / The plant Calotropis procera belonging to Asclepiadaceae is found around a vast extension of the Northeast from Brazil. It is a lactifers plant and its endogenous production of latex is admirable. Despite continuous reports appearing in the literature give mention to the medicinal properties of different parts of the plant, including the latex, there is not scientific approaches comprising biochemical of functional aspects of the latex from C. procera. The aims this work was determine the presence of endogenous enzymatic activities and inhibitory activity against different proteases and a-amylase, to evaluate insecticidal properties against different crop pests and to correlate enzymatic content and insecticidal action with possible role of the latex in protecting the plant to insect pathogens. The major soluble protein fraction from the latex was prepared following the protocol previously defined that includes centrifugations and dialysis steps. The protein fraction devoided of rubber and low molecular mass molecules was assayed to the presence of endogenous proteolytic activities as well as a-amylase activity. Even, the presence of inhibitor of such activities was investigated. Additionally the latex proteins were submitted to proteolysis by digestive content of different insects. Bioassays base on artificial diets with different contents of native, pronase digested or heated treated (98 ÂC) latex proteins were performed against six insects belonging to 4 different orders. Increment in bodyweight of larvae, time of development and percentage of survive were the parameters considered to analyze detrimental effects of latex proteins upon insects. The effect of latex proteins upon Callosbruchus maculatus insects by continuous exposure until F-6 generation was reached was performed. It was found strong endogenous proteolytic activity and latex proteins were resistent to proteolysis by insect digestive extracts. In addition chitinolytic activity was also detected. The latex exhibited insecticidal activity against different insect groups and this effect may be correlated to the presence of a cysteine protease inhibitor associated to its proteolytic properties and chitinolytic activity. It is suggested that the protein fraction of the latex from Calotropis procera plays a relevant role in defending the plant against pathogens.
65

Suscetibilidade a inseticidas e estruturação genética em populações de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) de diferentes regiões do Paraguai e Brasil / Susceptibility to insecticides and genetic structure in populations of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) collected in maize (Zea mays L.) from different regions of Paraguay and Brazil

Osmar René Arías Ruíz Díaz 13 July 2017 (has links)
Spodoptera frugiperda (J.E. Smith) tem sido uma das pragas mais importantes da cultura do milho no Paraguai e Brasil. Este trabalho foi realizado para subsidiar programas de manejo de resistência no Paraguai, reconhecendo-se a proximidade das fronteiras agrícolas desse país com Brasil e a alta capacidade de dispersão de S. frugiperda. Para tanto, foram realizados estudos de caracterização da suscetibilidade aos inseticidas lufenuron e flubendiamide e de diversidade genética e o fluxo gênico em populações de S. frugiperda coletadas nas principais regiões produtoras de milho do Paraguai e de dois Estados fronteiriços do Brasil (Mato Grosso do Sul e Paraná). O método de bioensaio para a caracterização das linhas-básica de suscetibilidade foi o de tratamento superficial da dieta artificial com o inseticida. As variações na suscetibilidade a lufenuron e flubendiamide entre as populações de S. frugiperda testadas foram baixas (< 4 vezes), comparando-se as populações das regiões Oriental e Ocidental do Paraguai que apresentam caraterísticas climáticas distintas ou entre as populações do Paraguai e do Brasil. Para o monitoramento da suscetibilidade de populações de S. frugiperda no Paraguai foram definidas as doses diagnósticas, baseada na DL99, de 0,16 &mu;g de lufenuron.cm-2 (equivalente a 10 &mu;g de lufenuron.mL-1 de água) e 2,84 &mu;g de flubendiamide.cm-2 (180 &mu;g de flubendiamide.mL-1 de água). Mediante o uso de 12 loci microssatélites, foram verificadas maior diversidade genética dentro das populações (87,70%) quando comparada entre as populações de cada país (9,91%) e entre países (2,39%). Sendo assim, não foi constatada alta estruturação genética entre as populações de S. frugiperda coletadas no Paraguai e Brasil. As populações do Paraguai mostraram-se mais distintas entre si quando comparadas com as populações do Brasil. Nossos resultados apontam baixa estruturação genética e moderado/alto fluxo gênico entre as localidades de coleta de populações de S. frugiperda e entre as populações do Paraguai e Brasil. Os resultados obtidos na presente pesquisa servirão para a implementação de um programa de manejo da resistência de S. frugiperda a inseticidas no Paraguai, com ênfase na necessidade de ações no âmbito regional considerando os estados fronteiriços do Brasil. / Spodoptera frugiperda (J.E. Smith) has been one of the most important corn pests in Paraguay and Brazil. This research was conducted to collect information to insect resistance management programs in Paraguay considering the proximity of agricultural borders of this country with Brazil and the high dispersal capacity of S. frugiperda. We conducted studies to characterize the susceptibility to the insecticides lufenuron e flubendiamide and to evaluate the genetic diversity and gene flow among S. frugiperda populations collected from major corn-producing regions in Paraguay and two frontier States of Brazil (Mato Grosso do Sul and Paraná). The bioassay method to characterize the baseline susceptibility was the diet surface treatment with the insecticide. The variation in the susceptibility to lufenuron and flubendiamide among S. frugiperda populations tested was low (< 4-fold) by comparing populations from Estearn and Western regions of Paraguay with distinct climatic conditions or populations from Paraguay and Brazil. For susceptibility monitoring to lufenuron and flubendiamide in S. frugiperda populations in Paraguay, we defined the diagnostic doses based on LD99 of 0.16 &mu;g of lufenuron.cm-2 (equivalent to 10 &mu;g of lufenuron.mL-1 of water) and 2,84 &mu;g of flubendiamide.cm-2 (180 &mu;g of flubendiamide.mL-1 of water). Using 12 microsatellite loci, higher genetic diversity within populations (87.70%) than among populations within each country (9.91%) and between countries (2.39%). Thus, there was no high genetic structure between S. frugiperda populations collected in Paraguay and Brazil. The populations of S. frugiperda from Paraguay were more distinct among themselves when compared with the populations from Brazil. Our results suggest low genetic structure and moderate/high gene flow among different sampling locations of S. frugiperda populations as well as between populations from Paraguay and Brazil. The results obtained in this research will support the implementation of resistance management programs of S. frugiperda to inseticides in Paraguay with focus on the need of plan of actions at regional level considering the border States of Brazil.
66

Detection And Characterization Of A Volatile Compound As A Response To Fall Armyworm (Spodoptera Frugiperda) Feeding In Maize (Zea Mays)

Smith, Whitney Elizabeth Crow 10 December 2010 (has links)
Maize (Zea mays) is an important agricultural crop frequently targeted by pests that pose a threat to plant development and survival. To deal with this problem, maize generates a wide variety of responses to attack by pests, from activation of woundresponse pathways to the release of volatile compounds. Several maize lines have been developed that show resistance to one common pest, the larvae of the fall armyworm (Spodoptera frugiperda). Analysis of the volatiles released by the resistant and susceptible lines in the presence and absence of the fall armyworm was conducted using SPME coupled to GC/MS. Caryophyllene, a commonly released plant volatile, was identified in the resistant line. In the susceptible line, caryophyllene was detected in smaller quantities or not at all. The results of a preference study demonstrated that fall armyworm larvae show a statistically significant preference for yellow-green whorl tissue from the susceptible over the resistant line.
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Regulation of productivity in Trichoplusia ni and Spodoptera frugiperda Sf9 serum-free cultures

Calles, Karin January 2005 (has links)
<p>The aim of this work has been to characterize the effects of conditioned medium (CM) on insect cell productivity and physiology in order to get a better understanding about the mechanisms that regulate productivity in serum-free media. Two cell lines have been investigated, Spodoptera frugiperda (Sf9) and Trichoplusia ni (T. ni, BTI-Tn-5B1-4). The baculovirus expression vector system (BEVS) was used for protein expression, using the ligand-binding domain of the human glucocorticoid receptor as a model protein. Addition of CM at inoculation led to a shorter lag phase and that the cells reached the maximum cell density faster than cells in fresh medium for both Sf9 and T. ni cells. Sf9 cells passed a switch in growth kinetics after 30-40 passages. At this point, CM lost its stimulating effect on proliferation. CM also affected the cell size and cell cycle progression. Sf9 and T. ni cells became smaller when CM was added at inoculation because they had a minor arrest in the cell cycle after inoculation and therefore started to divide earlier than cells in fresh medium. For Sf9 cells, this was illustrated by a smaller arrest in G2/M in the beginning of culture and the cells were consequently less synchronized. For T. ni cells, the initial decrease in the S phase population was followed by an earlier increase of the S phase population for the cells with CM than for the cells in fresh medium.</p><p>Addition of 20 % CM or CM filtrated with a 10 kDa cut-off filter to Sf9 cultures had a negative effect on the specific productivity. However, addition of CM to Sf9 cells that had passed the switch in growth kinetics had no negative effect on productivity. This indicates that CM not affects the protein production per se, but rather through its effects on cell physiology. Instead, the degree of cells synchronized in G2/M is important for high productivity and the gradually decreasing degree of synchronization during the course of a culture might be the explanation behind the cell density dependent decrease in productivity for Sf9 cells. This was further supported by the positive effects on productivity achieved by synchronizing Sf9 cells in G2/M by yeastolate limitation, which counteracted the cell density-dependent drop in productivity and hence a higher volumetric yield was achieved. Addition of 20 % CM to T. ni cultures had a positive effect on productivity. The specific productivity was maintained at a high level longer than for cells in 100 % fresh medium. The product concentration was 34 % higher and the maximum product concentration was obtained 24 hours earlier for the cells with the addition of CM. These results show that the effects of CM on productivity are not the same for the two cell lines and that the mechanism regulating productivity are quite complex.</p>
68

Physiological effects of conditioned medium and passage number on Spodoptera frugiperda Sf9 serum free cultures

Svensson, Ingrid January 2005 (has links)
<p>The aim of this study was to better understand the role of conditioned medium (CM) in Spodoptera frugiperda Sf9 insect cell proliferation and recombinant protein production using the baculovirus expression system.</p><p>CM was found to stimulate cell proliferation. Addition of CM and 10 kDa CM filtrate to an Sf9 culture decreased the lagphase and the maximum cell density was reached earlier than for cultures in fresh medium. The positive effect of 10 kDa CM filtrate showed that CM contains at least one small growth promoting factor. The effect was not eliminated by trypsin treatment. Addition of CM or 10 kDa CM filtrate to Sf9 cultures was found to have a negative effect on the recombinant protein production. The effect was thought to be indirect and most probably via the impact of CM on cell physiology. CM was also found to contain proteinase activity. The proteinase was identified as Sf9 cathepsin L. A proform with a molecular mass about 49 kDa and two active forms at about 39 and 22 kDa were found. The role of cathepsin L in Sf9 cultures is not yet clear. However, the knowledge of the presence of this proteinase in CM can be of great value for improving product quality and yield. Further, CM was found to have other properties as well: a concentrated fraction of CM exhibited strong antibacterial activity towards Bacillus megaterium and a weaker activity towards Escherichia coli. B. megaterium lysed rapidly after incubation in the CM fraction.</p><p>Repeated subculturing of Sf9 cells provoked a switch in growth kinetics. After 30-45 passages the cells started to proliferate earlier after inoculation and addition of CM had no longer a growth stimulating effect. However, CM still stimulated growth of a culture with low passage (LP) number (up to 45 passages). High passage cells (HP cells, over 100 passages) displayed a shorter lagphase than LP cells and the culture reached the maximum cell density 24-48 h earlier. Cell cycle analysis showed that the Sf9 cells were transiently synchronised in the G2/M phase 10 h after inoculation, before proliferation was initiated. This synchronisation was more pronounced for HP cells than for LP cells, which correlated to a higher recombinant protein production in baculovirus infected HP cells than in LP cells. Synchronisation of cells in G2/M by yeastolate-limitation before infection with baculoviruses suggested that the degree of synchronisation is connected to the cell density dependent decrease in recombinant protein production of Sf9 cultures.</p>
69

Analyse transcriptionnelle des phases précoces de l'infection par le baculovirus AcMNPV et exploitation d'une banque d'ADN complémentaire issue de sa cellule-hôte, Sf9

Landais, Igor 16 December 2002 (has links) (PDF)
Le lépidoptère Spodoptera frugiperda est un ravageur important des cultures mais aussi l'organisme source de la lignée cellulaire Sf9, utilisée pour la production de protéines recombinantes dans le système d'expression baculovirus/cellule d'insecte. Dans la première partie de ce travail, nous avons étudié la transcription chez le baculovirus AcMNPV aux temps précoces de l'infection. Nous montrons tout d'abord que les régions homologues (hrs) portées par le génome de ce virus contiennent de nombreux motifs de reconnaissance pour des facteurs de transcription de type AP1/CREB, et que ces sites fixent spécifiquement des protéines de la cellule-hôte, Sf9. Par ailleurs, dans le contexte de l'infection, ces sites sont nécessaires à la transactivation médiée par le facteur viral très précoce IE1 qui se fixe lui aussi sur les hrs. Cette étude montre pour la première fois l'implication de facteurs cellulaires dans ce mécanisme de transactivation virale. La progression de ces travaux a cependant été freinée par le peu de données disponibles sur les gènes exprimés par Sf9. Pour en faciliter l'accès, nous avons donc construit une banque d'ADNc, dont l'exploitation fait l'objet de la deuxième partie de ce mémoire. Son criblage a permis d'obtenir la séquence complète de l'ADN complémentaire du gène hsp90 chez S. frugiperda, et d'en déterminer les principales caractéristiques. Par ailleurs, le séquençage à grande échelle de la banque a conduit à la constitution d'une banque d'ESTs, permettant l'identification de la quasi-totalité des gènes de protéines ribosomales. L'analyse de leur séquence a révélé l'existence de particularités qui semblent restreintes aux insectes et aux lépidoptères, un résultat inattendu compte tenu de la grande conservation de ces gènes entre espèces.
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Efeitos subletais de óleos essenciais associados com Bacillus thuringiensis var. aizawai sobre Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). / Subsonic effects of essential oils associated with Bacillus thuringiensis var. Aizawai on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae).

CRUZ, Glaucilane dos Santos 01 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T15:23:56Z No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1016632 bytes, checksum: cf89201a0bacd4f7695775c34d5d1ad4 (MD5) / Made available in DSpace on 2016-11-24T15:23:56Z (GMT). No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1016632 bytes, checksum: cf89201a0bacd4f7695775c34d5d1ad4 (MD5) Previous issue date: 2012-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A large investment is annually demanded to control the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), which is the major insect pest of corn. To contain this demand alternative methods have been developed, including the use of botanical insecticides, known as essential oils, and entomopathogenic agents such as the bacterium Bacillus thuringiensis Berliner. These alternatives are adequate to Integrated Pest Management purposes, by being selective, low toxic to mammals and present efficiency against various pest species. Thus, we tested the hypothesis that association of long pepper and cloves oils at the concentrations of 30 and 50 mg/L DMSO with Xentari® WG (B. thuringiensis subsp. aizawai - Bta) (1000 mg/L) produces an efficient control of S. frugiperda, affecting biological, immunological and reproductive parameters, and if those concentrations of these oils affect spermatogenesis, the histochemistry of the ovarioles, as well as its impact on fertility. The results demonstrated that long pepper essential oil at a concentration of 50 mg/L associated with Bta has promoted lower larval survival, and clove does not proved efficient when combined with the Bta formulated. However, both oils, associated or not to Bta, interfered on the biology and humoral immunity of S. frugiperda. All treatments showed ovicidal effect except clove oil at the two concentrations without Bta. Histological analysis showed that clove and long pepper oils at the concentrations of 30 and 50 mg/L have affected spermatogenesis and the histochemistry of the ovarioles of S. frugiperda, reflecting on their reproduction. However, the effects of long pepper oil associated or not to Bta were more expressive, proving to be a promising tool to control this pest, adapting to MIP, controlling the survival of offspring and its success in the culture. / Anualmente demanda-se um alto investimento no controle da lagarta do cartucho Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), sendo esta a principal praga da cultura do milho. Para conter esta demanda métodos alternativos tem sido desenvolvidos, incluindo a utilização de inseticidas botânicos, conhecidos como óleos essenciais, e agentes entomopatogênicos, como a bactéria Bacillus thuringiensis Berliner. Estas alternativas adéquamse aos propósitos do Manejo Integrado de Pragas, por serem seletivos, de baixa toxicidade a mamíferos e apresentarem eficiência contra várias espécies de pragas. Assim, testou-se a hipótese de que a associação dos óleos de pimenta longa e cravo da Índia nas concentrações 30 e 50 mg/L DMSO com Xentari® WG (B. thuringiensis subsp. aizawai - Bta) (1000 mg/L) produzem um controle eficiente de S. frugiperda, afetando parâmetros biológicos, imunológicos e reprodutivos, e se as concentrações destes óleos afetam a espermatogênese, a histoquímica dos ovaríolos, bem como seu impacto na fertilidade. Os resultados demonstraram que o óleo de pimenta longa na concentração 50 mg/L associado ao Bta ocasionou menor sobrevivência larval, já o cravo da Índia não mostrou-se eficiente quando associado ao Bta formulado. Porém, ambos os óleos associados ou não ao Bta interferiram na biologia e na imunidade humoral de S. frugiperda. Todos os tratamentos afetaram a viabilidade dos ovos exceto a testemunha e o cravo da Índia nas duas concentrações sem Bta. A análise histológica mostrou que os óleos de pimenta longa e cravo da Índia nas concentrações 30 e 50 mg/L afetaram a espermatogênese e histoquímica dos ovaríolos de S. frugiperda, refletindo na sua reprodução. No entanto, os efeitos do óleo de pimenta longa, associado ou não ao Bta, foram mais expressivos, demonstrando ser uma ferramenta promissora no controle desta praga, adequando-se ao MIP, controlando a sobrevivência da prole e seu sucesso na cultura.

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