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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.
221

Coleoptera-specific (cry3aa) Delta-endotoxin Biosynthesis By A Local Isolate Of Bt Subsp. Tenebrionis, Gene Cloning And Characterization

Kurt, Aslihan 01 February 2005 (has links) (PDF)
Cry3Aa is a 73 kDa protoxin toxic to insect larvae of Coleoptera order. It is processed to form a stable 65 kDa &amp / #61540 / -endotoxin by endogenous proteases. The first part of this study involved the determination of the patterns of biosynthesis of Coleoptera-specific &amp / #61540 / -endotoxin by a local isolate of Bacillus thuringiensis subsp. tenebrionis (Btt) in relation to its growth and sporulation. Among four different media compared (DSM, GYS, HCT and C2) Cry3Aa production was the highest in DSM, especially at 72nd h and 120th h of incubation. For improvement of Cry3Aa production, the effects of different carbon and nitrogen sources, inorganic phosphate and other mineral elements were tested. Increasing concentrations (5-10 g.L-1) of glucose or sucrose decreased the toxin yield probably by suppressing sporulation. Inorganic phosphate was found to have the most striking effect on toxin biosynthesis. 200 mM inorganic phosphate concentration resulted in 5 fold increase in Cry3Aa yield. Cry3Aa production was greatly reduced when various combinations of organic and inorganic nitrogen sources, especially ammonium sulphate and Casamino acids were replaced with Nutrient broth in DSM. The highest Cry3Aa production was obtained in the media containing 10-5-10-7 M MnCl2, 10-5 M FeSO4 and 5.10-4 M MgSO4, corresponding to their original concentrations in DSM. Decrease of iron concentration or its omission from the medium decreased the toxin yield. Toxin production capacity of our local isolate was compared with those of 30 different anti-Coleopteran Bt strains. Most of the strains producing this protein gave general protein banding patterns quite similar to that of our local isolate. Lastly, the cry3Aa gene of the Btt local isolate was PCR-amplified and cloned into the E. coli/Bacillus shuttle vector pNW33N. The recombinant plasmid was amplified in E. coli and the sequence of the cry3Aa was determined. Amino acid sequence deduced was found to be 97.4 %-99.2 % identical to the cry3Aa sequences (GenBank) of 10 different quaternary ranks. In this respect, the gene has to represent the 11th quaternary rank of the cry3Aa ones. The recombinant plasmid carrying cry3Aa gene was next used to transform Bs 168 as an intermediate host and low level of expression was seen.
222

"The mode of action of Bacillus thuringiensis (Berliner) against the sheep louse, Bovicola ovis (Schrank)" / by Catherine Alexandra Hill.

Hill, Catherine Alexandra January 1998 (has links)
Bibliography: leaves 120-145. / vii, 145, [43] leaves, [23] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports Bt crystal protein toxicity to a phthirapteran species. Although Bt strain WB3516 may produce other unidentified toxins effective against B. ovis, the results provide strong evidence that the [delta]-endotoxin crystal proteins of strain WB3516 significantly contribute to the lousicidal toxicity of this strain. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1998?
223

Efficacité du gène rapporteur UIDA pour la sélection de plants d'épinette blanche génétiquement transformés avec le gène bt (Bacillus thuringiensis sous-espèce kurstaki) /

Ayisso, Justine. January 2003 (has links)
Thèse (M.Sc.)--Université Laval, 2003. / Bibliogr.: f. 81-94. Publié aussi en version électronique.
224

Suscetibilidade e interação de proteínas Cry1 e Vip3A de Bacillus thuringiensis para o controle de lepidópteros-praga

Crialesi, Paula Cristina Brunini [UNESP] 16 December 2013 (has links) (PDF)
Made available in DSpace on 2014-08-13T14:50:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-16Bitstream added on 2014-08-13T18:01:02Z : No. of bitstreams: 1 000748612_20150116.pdf: 262543 bytes, checksum: 83687670798f532aa71d1023029e6d35 (MD5) Bitstreams deleted on 2015-01-23T10:59:20Z: 000748612_20150116.pdf,Bitstream added on 2015-01-23T10:59:52Z : No. of bitstreams: 1 000748612.pdf: 1126755 bytes, checksum: d94522b75e5a7b2b4fd318e70207535a (MD5) / Os inseticidas químicos são amplamente utilizados no controle de insetos-praga, no entanto, causam enormes prejuízos ambientais. Uma alternativa a esses inseticidas é a utilização de microrganismos entomopatogênicos, que controlam seletivamente os insetos e preservam o meio ambiente. A bactéria Bacillus thuringiensis Berliner é considerada a espécie de maior interesse neste cenário, pois é responsável pela produção de proteínas inseticida. Genes de B. thuringiensis vêm sendo amplamente estudados e utilizados na construção de culturas transgênicas no mundo todo. No entanto, quando não associadas a áreas de refúgio podem acelerar a seleção de organismos resistentes em populações de insetos-praga. Estudos relatam a necessidade em retardar a evolução da resistência a insetos-praga e dentre as possibilidades, a utilização de mais de um gene na construção de plantas transgênica mostra-se eficiente. Desta forma, o presente estudo avaliou a suscetibilidade de Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) e Chrysodeixis includens (Walker, 1857) (Lepidoptera: Noctuidae) às proteínas de B. thuringiensis, Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ca, Cry1Ea, Vip3Aa, Vip3Ae e Vip3Af. Após estimar a CL50 de cada proteína para cada espécie avaliou-se a interação entre as combinações de Vip3A+Cry1 e Cry1+Cry1. Os resultados sugerem que todas as proteínas foram eficientes no controle de ambas as espécies, destacando-se a proteína Cry1Ac (0,75 ng.cm-2) para A. gemmatalis e a proteína Vip3Af (1,4 ng.cm-2) para C. includens. O padrão geral de comparação da suscetibilidade das espécies frente às proteínas avaliadas indicou que há uma diferença significativa na toxicidade das proteínas para cada espécie. Verificou-se uma grande inibição do desenvolvimento larval de lagartas sobreviventes a CL50 de cada proteína. As interações das proteínas indicaram ... / Chemical insecticides are widely used to control insect pests, however, cause enormous environmental damage. An alternative to these insecticides is the use of entomopathogenic microorganisms which selectively control insects and preserve the environment. The Bacillus thuringiensis Berliner is the species of greatest interest responsible for production of insecticidal proteins. Genes of B. thuringiensis have been widely studied and used in the construction of transgenic crops worldwide. However, when not associated with refuge areas can accelerate the selection of resistant organisms in populations of insect pests. Studies have reported the need to slow the evolution of resistance to insect pests and among the possibilities, the use of more than one gene in the construction of transgenic plants proves efficient. Thus, the present study evaluated the susceptibility of Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) and Chrysodeixis includens (Walker, 1857) (Lepidoptera: Noctuidae), from the proteins isolated from B. thuringiensis Cry1Aa , Cry1Ab , Cry1Ac , Cry1Ca , Cry1Ea , Vip3Aa , Vip3Ae and Vip3Af . After estimating the LC50 of each protein for each species evaluated the interaction between combinations of Vip3A + Cry1 and Cry1 + Cry1. The results suggest that all proteins were effective in controlling both species, emphasized the Cry1Ac protein (0.75 ng.cm-2) to A. gemmatalis and Vip3Af protein (1.4 ng.cm-2) to C. includens. A comparison of the susceptibility of the species to proteins indicated that there is a significant difference in toxicity for each species. There was a large inhibition of larval development of caterpillars surviving the LC50 of each protein. The interactions of proteins indicated the synergistic combinations Vip3Aa + Cry1Ea, Cry1Aa + Cry1Ab and Cry1Ea + Cry1Ac as alternatives for the control and management of resistance in A. gemmatalis and C. includens ...
225

Suscetibilidade e interação de proteínas Cry1 e Vip3A de Bacillus thuringiensis para o controle de lepidópteros-praga /

Crialesi, Paula Cristina Brunini. January 2013 (has links)
Orientador: Janete Apparecida Desidério / Coorientador: Odair Aparecido Fernandes / Banca: Manoel Victor Franco Lemos / Banca: Ricardo Antonio Polanczyk / Banca: Alexandre de Sene Pinto / Banca: Ana Maria Guidelli Thuler / Resumo: Os inseticidas químicos são amplamente utilizados no controle de insetos-praga, no entanto, causam enormes prejuízos ambientais. Uma alternativa a esses inseticidas é a utilização de microrganismos entomopatogênicos, que controlam seletivamente os insetos e preservam o meio ambiente. A bactéria Bacillus thuringiensis Berliner é considerada a espécie de maior interesse neste cenário, pois é responsável pela produção de proteínas inseticida. Genes de B. thuringiensis vêm sendo amplamente estudados e utilizados na construção de culturas transgênicas no mundo todo. No entanto, quando não associadas a áreas de refúgio podem acelerar a seleção de organismos resistentes em populações de insetos-praga. Estudos relatam a necessidade em retardar a evolução da resistência a insetos-praga e dentre as possibilidades, a utilização de mais de um gene na construção de plantas transgênica mostra-se eficiente. Desta forma, o presente estudo avaliou a suscetibilidade de Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) e Chrysodeixis includens (Walker, 1857) (Lepidoptera: Noctuidae) às proteínas de B. thuringiensis, Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ca, Cry1Ea, Vip3Aa, Vip3Ae e Vip3Af. Após estimar a CL50 de cada proteína para cada espécie avaliou-se a interação entre as combinações de Vip3A+Cry1 e Cry1+Cry1. Os resultados sugerem que todas as proteínas foram eficientes no controle de ambas as espécies, destacando-se a proteína Cry1Ac (0,75 ng.cm-2) para A. gemmatalis e a proteína Vip3Af (1,4 ng.cm-2) para C. includens. O padrão geral de comparação da suscetibilidade das espécies frente às proteínas avaliadas indicou que há uma diferença significativa na toxicidade das proteínas para cada espécie. Verificou-se uma grande inibição do desenvolvimento larval de lagartas sobreviventes a CL50 de cada proteína. As interações das proteínas indicaram ... / Abstract: Chemical insecticides are widely used to control insect pests, however, cause enormous environmental damage. An alternative to these insecticides is the use of entomopathogenic microorganisms which selectively control insects and preserve the environment. The Bacillus thuringiensis Berliner is the species of greatest interest responsible for production of insecticidal proteins. Genes of B. thuringiensis have been widely studied and used in the construction of transgenic crops worldwide. However, when not associated with refuge areas can accelerate the selection of resistant organisms in populations of insect pests. Studies have reported the need to slow the evolution of resistance to insect pests and among the possibilities, the use of more than one gene in the construction of transgenic plants proves efficient. Thus, the present study evaluated the susceptibility of Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) and Chrysodeixis includens (Walker, 1857) (Lepidoptera: Noctuidae), from the proteins isolated from B. thuringiensis Cry1Aa , Cry1Ab , Cry1Ac , Cry1Ca , Cry1Ea , Vip3Aa , Vip3Ae and Vip3Af . After estimating the LC50 of each protein for each species evaluated the interaction between combinations of Vip3A + Cry1 and Cry1 + Cry1. The results suggest that all proteins were effective in controlling both species, emphasized the Cry1Ac protein (0.75 ng.cm-2) to A. gemmatalis and Vip3Af protein (1.4 ng.cm-2) to C. includens. A comparison of the susceptibility of the species to proteins indicated that there is a significant difference in toxicity for each species. There was a large inhibition of larval development of caterpillars surviving the LC50 of each protein. The interactions of proteins indicated the synergistic combinations Vip3Aa + Cry1Ea, Cry1Aa + Cry1Ab and Cry1Ea + Cry1Ac as alternatives for the control and management of resistance in A. gemmatalis and C. includens ... / Doutor
226

Monografía sobre el estado del arte del control microbiológico de la polilla del tomate, Tuta absoluta (Meyrick) (Lepidoptera: Gelechidae): microorganismos más utilizados y su efectividad / MONOGRAPHY ON THE STATE OF THE ART IN MICROBIAL CONTROL OF THE TOMATO BORER, Tuta absoluta (Meyrick) (LEPIDOPTERA: GELECHIIDAE): MOST UTILIZED MICROORGANISMS AND THEIR EFFECTIVENESS

Gajardo Retamal, Sergio Pablo January 2016 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo / El tomate (Solanum lycopersicum L.) es el cultivo hortícola de mayor importancia a nivel mundial, sin embargo, su rendimiento se ve constantemente afectado por el persistente ataque de plagas y enfermedades a lo largo de la temporada. Dentro de las plagas primarias que afectan al cultivo en Chile, la polilla del tomate (Tuta absoluta Meyrick) es muy relevante, ya que puede ocasionar pérdidas cercanas al 90% en el rendimiento al no ser controlada. El principal método de control de este lepidóptero se ha restringido tradicionalmente al uso de plaguicidas de origen químico, práctica que en la actualidad está siendo fuertemente cuestionada debido al daño al ambiente, a insectos benéficos, a la salud humana, así como también por el desarrollo de resistencia a estos productos por parte de la plaga.
227

Virulência de micro-organismos à Plutella xylostella (L.) (Lepidoptera: Plutellidae) e compatibilidade com inseticidas

Duarte, Rogério Teixeira [UNESP] 13 November 2015 (has links) (PDF)
Made available in DSpace on 2016-04-01T17:55:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-11-13. Added 1 bitstream(s) on 2016-04-01T18:00:50Z : No. of bitstreams: 1 000859537.pdf: 1310893 bytes, checksum: 012fcc78c457be5b4cb95c562dd018af (MD5) / A traça-das-crucíferas, Plutella xylostella (L.) (Lepidoptera: Plutellidae), é uma das principais pragas da família Brassicaceae, com controle baseado no uso indiscriminado de inseticidas, o que tem propiciado o aumento no número de casos de populações resistentes a diferentes ingredientes ativos. O controle biológico com a utilização de micro-organismos entomopatogênicos constitui uma importante ferramenta para o manejo desta praga. Entretanto, o principal entrave quanto à eficiência e conservação destes agentes microbianos no campo está relacionado à compatibilidade com os agrotóxicos. O objetivo da pesquisa foi analisar a suscetibilidade de P. xylostella a micro-organismos entomopatogênicos e avaliar a compatibilidade dos entomopatógenos mais virulentos com inseticidas registrados para o controle do complexo de pragas da cultura do repolho. Foi analisada a eficiência de 13 isolados da bactéria entomopatogênica Bacillus thuringiensis, além de isolados dos fungos entomopatogênicos Beauveria bassiana, Metarhizium rileyi, Isaria fumosorosea, I. sinclairii e Lecanicillium muscarium, através da realização de testes de patogenicidade e virulência (CL50 e TL50) sobre lagartas de segundo ínstar de P. xylostella. A interação entre os isolados e os ingredientes ativos foi realizada a partir da mistura do inseticida no meio de cultura, sendo inoculada uma alíquota da suspensão do micro-organismo após o meio se solidificar, sendo avaliado o número de esporos/mL (B. thuringiensis) e o crescimento da colônia, o número e a viabilidade dos conídios (fungos entomopatogênicos), após um período de sete dias da inoculação destes micro-organismos. Os isolados HD-1, HD-4, HD-11, HD-73 e T-07 de B. thuringiensis foram os mais eficientes no controle de P. xylostella, responsáveis por ocasionar mortalidade total das lagartas, com CL50 variando entre 0,75 e 11,66 × 103 esporos/mL e TL50 entre 25,12 e 34,47 h. Os isolados... / Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the main pest in Brassicaceae family with control based on the indiscriminate use of insecticides, which has provided an increase in the number of cases of resistant populations to different active ingredients. Biological control, by using of entomopathogenic microorganisms is an important tool for the management of this pest. However, the main obstacle in terms of efficiency and conservation of these microbial agents in the field is related to the compatibility with pesticides. The aim of the research was to analyze the susceptibility of P. xylostella to entomopathogenic microorganisms and evaluate the compatibility of the most virulent entomopathogens with insecticides registered for the control of pest complex in cabbage crop. Efficiency of 13 isolates of the entomopathogenic bacterium Bacillus thuringiensis was analyzed, in addition to isolates of the entomopathogenic fungi Beauveria bassiana, Metarhizium rileyi, Isaria fumosorosea, I. sinclairii and Lecanicillium muscarium by performing pathogenicity and virulence tests (LC50 and LT50) on second instar larvae of P. xylostella. The interaction between the isolates and active ingredients was made from the mixture of the insecticide in the culture medium, inoculated with an aliquot of the microorganism suspension after medium solidify, evaluated the number of spores / mL (B. thuringiensis), and the colony growth, the number and conidia viability (entomopathogenic fungi) after seven days the inoculation of these microorganisms. The isolates of B. thuringiensis HD-1, HD-4, HD-11, HD-73 and T-07were the most efficient in P. xylostella control, responsible for overall mortality, with LC50 ranging from 0.75 to 11.66 × 103 spores / mL and TL50 between 25.12 to 34.47 h. The isolates IBCB01, IBCB18, IBCB66 and IBCB87 of B. bassiana, LCMAP101 of M. rileyi and ARSEF7973 of I. sinclairii caused mortality between ...
228

Bacillus thuringiensis var. israelensis SPS1: caracterização da região promotora de genes cry e efeito em larvas de Aedes aegypti (L.) (Diptera: Culicidae)

Rossi, Juliana Regina [UNESP] 13 July 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-13Bitstream added on 2014-06-13T19:12:59Z : No. of bitstreams: 1 rossi_jr_me_jabo.pdf: 1016425 bytes, checksum: 885b9804e9660ef2c359c1d1eb71a757 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dentre os microrganismos empregados no controle de mosquitos, a bactéria Bacillus thuringiensis var. israelensis (Bti) se destaca por apresentar atividade tóxica contra insetos da ordem Diptera, na qual produz inclusões cristalinas compostas pelas proteínas Cry, que são codificadas por genes cry presentes em um único plasmídeo. A produção dessas proteínas em grande escala está relacionada a mecanismos transcricionais, como por exemplo, a expressão de um gene sob o controle de um promotor forte. Tendo em vista que a bactéria Bti SPS1 (Patente PI0200228-0) foi isolada do território brasileiro e que possui potencial para o controle de vetores por produzir uma maior quantidade de esporos/cristais em menor tempo, este trabalho teve por finalidade a caracterização da região promotora dos genes cry4Aa, cry4Ba e cry11Aa de Bti SPS1 pelas técnicas de PCR e “Southern blotting”. Em associação a estas técnicas, foi realizado bioensaio para a verificação da mortalidade de larvas de Aedes aegypti. Os resultados das análises moleculares indicaram homologia no perfil de hibridização da região promotora da linhagem padrão Bti T14-001 e do isolado Bti SPS1. A quantificação das suspensões em espectrofotômetro (DO600nm) e a leitura de esporos em câmara de Neubauer, revelaram que o isolado Bti SPS1 produz uma maior quantidade de esporos/cristais em relação à linhagem padrão Bti T14-001. O bioensaio apresentou elevados índices de mortalidade. Estes resultados tornam a bactéria Bti SPS1 uma fonte promissora para novas formulações visando o controle de vetores. / Among the microorganisms used for mosquitoes’ control the bacterium Bacillus thuringiensis var. israelensis (Bti) is frequently considered since it presents toxic activities’ against Diptera, producing crystal inclusions including Cry proteins, which are coded by a sole plasmid borne set of genes. The production of these proteins in large scale is related to transcriptional mechanisms, as an example, a particular gene expression controlled by a strong promoter. Since the Bti bacterial isolate SPS1 (Patent PI0200228-0) was isolated within the Brazilian territory and exhibits potential for the control of vector insects due to a higher crystal production ability in shorter time period, this work had as objective the characterization of the promotion region for the genes cry4Aa, cry4Ba e cry11Aa using PCR and “Southern blotting” techniques. Also some bioassays using Aedes aegypti larvae were carried out. The results from the molecular analysis have indicated homology for the hybridization profile from the promoter region from the type strain of Bti T14-001 and that of the SPS1 isolate. Spectrofotometric (OD600nm) and Neubauer chamber measures have revealed that the SPS1 isolate produces a higher amount of spore/crystal as compared to the Bti T14-001 strain. The bioassay presented higher mortality levels. These results seem to indicate that the isolate SPS1 is a promising bacterial strain to be used on formulations able to control insect vector pests.
229

Seleção e caracterização de novos genes vip3A: genes inseticidas de segunda geração de Bacillus thuringiensis

Marucci, Suzana Cristina [UNESP] 03 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-03Bitstream added on 2014-06-13T20:14:46Z : No. of bitstreams: 1 marucci_sc_me_jabo_parcial.pdf: 42548 bytes, checksum: 705ccf6a74fac7e11f4cb25dc8fb9403 (MD5) Bitstreams deleted on 2015-01-16T10:37:51Z: marucci_sc_me_jabo_parcial.pdf,Bitstream added on 2015-01-16T10:38:35Z : No. of bitstreams: 1 000638549.pdf: 1096070 bytes, checksum: 93634385c53868612602ba315f79ea43 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Como uma alternativa para diminuir as agressões constantes que o ecossistema vem sofrendo, devido à grande quantidade de produtos químicos utilizados no controle de pragas, pesquisas envolvendo microrganismos capazes de promover o controle biológico tem se intensificado. Dentre estes microrganismos a bactéria Bacillus thuringiensis tem se destacado. Essa bactéria caracteriza-se pela produção de proteínas tóxicas a representantes de diversas ordens de insetos. Em particular, as proteínas Vip3A, estão em amplo estudo devido a sua especificidade, alto potencial ativo e como alternativa para o controle da resistência de insetos às proteínas Cry. Diante disto, o objetivo deste trabalho foi selecionar, a partir de 1080 isolados de diferentes regiões brasileiras, aqueles portadores de genes vip3A e obter a sequência de nucleotídeos completa dos mesmos. As linhagens padrão B. thuringiensis var. kurstaki HD1, B. thuringiensis var. tolworthi HD125 e o isolado I187 tiveram seus DNAs amplificados com oligonucleotídeos baseados na sequência de genes vip3A, descritos no banco de dados de B. thuringiensis e, a partir dos amplicons obtidos, a sequência completa de nucleotídeos dos mesmos foi determinada, utilizando-se da estratégia de “primer walking”. A proteína Vip3Aa43 (GenBank: [HQ594534]) da linhagem HD1 demonstrou ser 100% idêntica às proteínas Vip3Aa já descritas. Já as proteínas Vip3Aa42 (GenBank: [HQ587048]) da linhagem HD125 e Vip3Ag5 (GenBank: [HQ542193]) do isolado I187 demonstraram similaridade de 99% com as proteínas descritas Vip3Aa35 e Vip3Ag2, respectivamente, demonstrando serem duas novas proteínas Vip3A, devido às substituições de aminoácidos ocorridas. Os três genes vip3A obtidos poderão ser utilizados na produção de plantas Bt, piramidadas ou não, visando ao manejo da resistência dos insetos praga / As an alternative to decrease the constant aggressions that the ecosystem has suffered due to the large amount of chemical products used in pest control, researches involving microorganisms able to promoting biological control have been intensified. Among these microorganisms the bacterium Bacillus thuringiensis has been stood out. This bacterium is characterized by the production of toxic proteins to representatives of several insect orders. In particular, the Vip3A proteins are in large study due to its specificity, and high active potential as an alternative to control of insect's resistance to Cry proteins. According to this, the aim of this work was to select from 1080 isolates in different Brazilian regions, those carrying vip3A genes and obtain the complete nucleotide sequence of the same. The standard strains B. thuringiensis var. kurstaki HD1, B. thuringiensis var. tolworthi HD125 and the isolate I187 had their DNA amplified with primers based on vip3A gene sequence described in database of B. thuringiensis, and from the amplicons obtained, the full sequence of nucleotides was determined, by the use of the strategy of primer walking. The protein Vip3Aa43 (GenBank: [HQ594534]) of HD1 strain showed to be 100% identical to Vip3Aa proteins already described. However, the proteins Vip3Aa42 (GenBank: [HQ587048]) of HD125 strain and Vip3Ag5 (GenBank: [HQ542193]) of the isolate I187 showed 99% similarity with the Vip3Aa35 and Vip3Ag2 proteins described, respectively, showing been two new Vip3A proteins due to amino acid substitutions occurred. The three vip3A genes obtained can be used in the production of Bt crops, pyramidal or not, aiming to resistance management of pest insects
230

Virulência de micro-organismos à Plutella xylostella (L.) (Lepidoptera: Plutellidae) e compatibilidade com inseticidas /

Duarte, Rogério Teixeira. January 2015 (has links)
Orientador: Ricardo Antonio Polanczyk / Banca: Sergio Antonio De Bortoli / Banca: Arlindo Leal Boiça Junior / Banca: Italo Delalibera Júnior / Banca: Roberto Marchi Goulart / Resumo: A traça-das-crucíferas, Plutella xylostella (L.) (Lepidoptera: Plutellidae), é uma das principais pragas da família Brassicaceae, com controle baseado no uso indiscriminado de inseticidas, o que tem propiciado o aumento no número de casos de populações resistentes a diferentes ingredientes ativos. O controle biológico com a utilização de micro-organismos entomopatogênicos constitui uma importante ferramenta para o manejo desta praga. Entretanto, o principal entrave quanto à eficiência e conservação destes agentes microbianos no campo está relacionado à compatibilidade com os agrotóxicos. O objetivo da pesquisa foi analisar a suscetibilidade de P. xylostella a micro-organismos entomopatogênicos e avaliar a compatibilidade dos entomopatógenos mais virulentos com inseticidas registrados para o controle do complexo de pragas da cultura do repolho. Foi analisada a eficiência de 13 isolados da bactéria entomopatogênica Bacillus thuringiensis, além de isolados dos fungos entomopatogênicos Beauveria bassiana, Metarhizium rileyi, Isaria fumosorosea, I. sinclairii e Lecanicillium muscarium, através da realização de testes de patogenicidade e virulência (CL50 e TL50) sobre lagartas de segundo ínstar de P. xylostella. A interação entre os isolados e os ingredientes ativos foi realizada a partir da mistura do inseticida no meio de cultura, sendo inoculada uma alíquota da suspensão do micro-organismo após o meio se solidificar, sendo avaliado o número de esporos/mL (B. thuringiensis) e o crescimento da colônia, o número e a viabilidade dos conídios (fungos entomopatogênicos), após um período de sete dias da inoculação destes micro-organismos. Os isolados HD-1, HD-4, HD-11, HD-73 e T-07 de B. thuringiensis foram os mais eficientes no controle de P. xylostella, responsáveis por ocasionar mortalidade total das lagartas, com CL50 variando entre 0,75 e 11,66 × 103 esporos/mL e TL50 entre 25,12 e 34,47 h. Os isolados... / Abstract: Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the main pest in Brassicaceae family with control based on the indiscriminate use of insecticides, which has provided an increase in the number of cases of resistant populations to different active ingredients. Biological control, by using of entomopathogenic microorganisms is an important tool for the management of this pest. However, the main obstacle in terms of efficiency and conservation of these microbial agents in the field is related to the compatibility with pesticides. The aim of the research was to analyze the susceptibility of P. xylostella to entomopathogenic microorganisms and evaluate the compatibility of the most virulent entomopathogens with insecticides registered for the control of pest complex in cabbage crop. Efficiency of 13 isolates of the entomopathogenic bacterium Bacillus thuringiensis was analyzed, in addition to isolates of the entomopathogenic fungi Beauveria bassiana, Metarhizium rileyi, Isaria fumosorosea, I. sinclairii and Lecanicillium muscarium by performing pathogenicity and virulence tests (LC50 and LT50) on second instar larvae of P. xylostella. The interaction between the isolates and active ingredients was made from the mixture of the insecticide in the culture medium, inoculated with an aliquot of the microorganism suspension after medium solidify, evaluated the number of spores / mL (B. thuringiensis), and the colony growth, the number and conidia viability (entomopathogenic fungi) after seven days the inoculation of these microorganisms. The isolates of B. thuringiensis HD-1, HD-4, HD-11, HD-73 and T-07were the most efficient in P. xylostella control, responsible for overall mortality, with LC50 ranging from 0.75 to 11.66 × 103 spores / mL and TL50 between 25.12 to 34.47 h. The isolates IBCB01, IBCB18, IBCB66 and IBCB87 of B. bassiana, LCMAP101 of M. rileyi and ARSEF7973 of I. sinclairii caused mortality between ... / Doutor

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