Le tube digestif est la première barrière contre les agresseurs présents dans la nourriture (virus, bactéries, produits chimiques, pesticides etc...). Il doit donc maintenir au mieux son intégrité structurale et fonctionnelle tout au long de la vie de l'individu. Bien que l'impact délétère d'une intoxication aiguë puisse être surmonté par la capacité de défense et de régénération de la muqueuse digestive, une agression prolongée ou répétée peut compromettre l'équilibre physiologique (l'homéostasie) du tube digestif. Parmi les agresseurs pouvant être ingérés avec la nourriture, on trouve la bactérie Bacillus thuringiensis (Bt) et représente 70% des ventes de bioinsecticides. Bt est une bactérie Gram+ sporulante qui produit, pendant la sporulation, des toxines nommées Cry. Parmi les différentes souches de Bt, certaines ont été sélectionnées pour la spécificité d'action de leurs toxines Cry contre des nuisibles et sont commercialisées sous forme de sporanges. Certaines de ces souches sont utilisées en agriculture biologique en France et l'accroissement de leur utilisation fait qu'elles sont de plus en plus présentes dans la nourriture, source de contamination potentielle pour l'homme et l’environnement. La question qui se pose maintenant est de savoir si un tel accroissement de l’utilisation de Bt peut avoir des impacts sur des espèces non cibles. Mon projet de thèse a consisté en l’étude des conséquences de l'ingestion de Bt (sous forme végétative ou de sporanges) sur la physiologie intestinale de la drosophile (animal non sensible à Bt en termes de toxicité aigüe / The digestive tract is continuously subjected to multiple aggressions through virus, bacteria, toxins and chemicals mixed in the feed. Therefore the gut lining has established a mechanism of replenishment in order to maintain the physiological function of the organ called the gut homeostasis. Although the deleterious impact of acute poisoning can be overcome by the defense capacity and regeneration of the gut mucosa, prolonged or repeated intoxication can impair its homeostasis. Among the aggressors hidden in the feed, there is the bacterium Bacillus thuringiensis (Bt). Bt is worldwide used as bioinsecticide. Indeed the multitude of Bt strains produces a broad range of crystalline toxins, named Cry toxins, which certain have been selected in organic farming owing to their lethal properties against specific pests. Because of incentive programs for sustainable development, the use of Bt bioinsecticides as an alternative to chemical pesticides will further increase in the next decades. Although the specificity of the acute toxicity of Cry toxins has been proved since many years, data are scarce on adverse effects that could result from chronic exposure. The question now is how far non-target organisms will be potentially impacted by the resulting augmentation of the Bt bacterium and its Cry toxins in the environment. To answer this challenge, I used Drosophila (a non-target organism) to study the impacts of Bt bioinsecticides on the gut physiology because 1/ the digestive tract is the main entrance for feed contaminated by Bt bioinsecticides and 2/ Bt and its toxins are known to impair the gut epithelium of sensitive pests

Bacillus thuringiensis (B. thuringiensis) es una bacteria Gram positiva que forma un cristal paraesporal con actividad insecticida contra insectos de diferentesórdenes. Los bioinsecticidas fabricados con las esporas y cristales de B. thuringiensis son una alternativa frente a los pesticidas químicos sintéticos para el control de mosquitos que son vectores de enfermedades metaxénicas, como por ejemplo, malaria y dengue. Se caracterizaron 53 cepas nativas de B. thuringiensis, procedentes de suelos peruanos, de los departamentos de Junín, Lima (Huaral), Ica, Cuzco, Tacna, Arequipa, Chiclayo y Cajamarca; dos de ellas codificadas como Ica10 y Caj1 por su procedencia, presentaron actividad entomocida contra larvas de Aedes aegypti. Se observan cepas que presentan bandas (toxinas) con pesos moleculares en el órden de los 36 kDa y mayores a 116 kDa; otras cepas presentan bandas a 97 y 75 kDa, como las de, Cajamarca, Arequipa y Chiclayo, que serían entomocidas para dípteros, algunas cepas presentaron bandas de 130 kDa que corresponderían al gen cry1, tóxico para lepidópteros. El gen cry2 fue el más frecuente (92%), seguido de cry1 (45%) y cry4 (42%), lo cual significaría que las cepas tendrían principalmente, actividad entomocida contra dípteros. El secuenciamiento confirmó la presencia de genes cry en 62 de 67 cepas analizadas. Se determinó la cepa B. thuringiensis Cuz5 como variedad cry2Ab. El método del PCR fue efectivo para caracterizar rápidamente las cepas en base al contenido de genes que amplifican con secuencias de oligonucleótidos conocidos. El método REP-PCR mostró patrones de bandas diferentes en las cepas aisladas que podría significar variabilidad genética entre las cepas estudiadas, el dendograma permitió agruparlas en tres clusters y subclusters que podrían deberse a las variedades del gen cry. Palabras claves: Bacillus thuringiensis, cristal paraesporal, entomocida, gen cry, control de plagas. / *** Bacillus thuringiensis (B. thuringiensis), is a Gram-positive bacterium, that forms a parasporal crystals with insecticidal activity against different insect orders. Bioinsecticides manufactured with B. thuringiensis spores and crystals are a useful alternative to synthetic chemical pesticide in agriculture and for mosquito control. B. thuringiensis has also been used successfully to suppress the population levels of medically important dipteran pests. Examples include the mosquito vectors of malaria, virus diseases including dengue. It was characterized 53 strains peruanas of Bacillus thuringiensis with entomocidal properties from soil Peruvian’s farms of the deparments of Junín, Lima (Huaral), Ica, Cuzco, Tacna, Arequipa, Chiclayo y Cajamarca, two: Ica10 y Caj1 with activity against Aedes aegypti. There are strains with toxins betwen 36 y 116kDa. Strains with bands to 97 and 70KDa, as those of Arequipa, Cajamarca and Chiclayo, which would be entomocidal with band of 130 kDa that correspond to cry gen, toxic to Lepidoptera and Diptera. Cry2 gene was the most abundant (92%), followed by cry1 (45%) and cry 4 (42%), which means that the strains would have activity against Dipterans. The sequencing confirms the content of cry genes in most of the analyzed strains. The strain Cuz5 as variety cries 2Ab. The PCR method is effective to rapidly characterize the strains based on the content of genes that amplify with known sequences of oligonucleótidos and REP-PCR shows patterns of different bands in the isolated strains that could mean genetic variability among the studied strains, the dendogram allows to group them into three clusters and subclusters, that might be due to the varieties of the gene cry. Key words: Bacillus thuringiensis, parasporal crystal, entomocida, cry gene, crop pestes.

Background: The pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) is one of the world's most important pests of cotton. Insecticide sprays and transgenic cotton producing toxins of the bacterium Bacillus thuringiensis (Bt) are currently used to manage this pest. Bt toxins kill susceptible insects by specifically binding to and destroying midgut cells, but they are not toxic to most other organisms. Pink bollworm is useful as a model for understanding insect responses to Bt toxins, yet advances in understanding at the molecular level have been limited because basic genomic information is lacking for this cosmopolitan pest. Here, we have sequenced, de novo assembled and annotated a comprehensive larval midgut transcriptome from a susceptible strain of pink bollworm. Findings: A de novo transcriptome assembly for the midgut of P. gossypiella was generated containing 46,458 transcripts (average length of 770 bp) derived from 39,874 unigenes. The size of the transcriptome is similar to published midgut transcriptomes of other Lepidoptera and includes up to 91 % annotated contigs. The dataset is publicly available in NCBI and GigaDB as a resource for researchers. Conclusions: Foundational knowledge of protein-coding genes from the pink bollworm midgut is critical for understanding how this important insect pest functions. The transcriptome data presented here represent the first large-scale molecular resource for this species, and may be used for deciphering relevant midgut proteins critical for xenobiotic detoxification, nutrient digestion and allocation, as well as for the discovery of protein receptors important for Bt intoxication.

Insecticidal proteins from Bacillus thuringiensis (Bt) are used widely in sprays and transgenic plants to control insect pests. Although much research has elucidated the effects of Bt toxins on larvae, relatively little is known about their effects on adults. Here, we evaluated the effects of exposing adults to Bt toxin Cry1Ac on the life span and reproduction of two strains of pink bollworm (Pectinophora gossypiella (Saunders)). In larval diet bioassays, the concentration of Cry1Ac killing 50% of larvae (LC50) was 640 times higher for the laboratory-selected resistant strain (AZP-R) than the susceptible strain (APHIS-S). In experiments with adults, the highest concentrations of Cry1Ac tested (160 and 640 mu g Cry1Ac per ml of 5% honey water) reduced life span for both strains. Treatments with 10, 40, and 160 mg Cry1Ac per ml reduced the duration of the oviposition period as well as the number of eggs laid by both strains, but did not affect the percentage of pairs producing eggs, the duration of the preoviposition period, or the percentage of eggs hatching for either strain. Adult life span did not differ between strains at low to moderate concentrations of Cry1Ac, but it was significantly greater for the resistant strain than the susceptible strain at the two highest concentrations of Cry1Ac tested. The reduced susceptibility to high concentrations of Cry1Ac in adults of the AZP-R strain relative to the APHIS-S strain provides the first evidence of expression of resistance to a Bt toxin in adult Lepidoptera.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Orientador: Antonio Carlos Busoli / Banca: Marcos Doniseti Michelotto / Banca: Raphael de Campos Castilho / Banca: José Roberto Scarpellini / Banca: Arlindo Leal Boiça Junior / Resumo: O cenário agrícola no Centro Oeste conta com os chamados sistemas de produção, nos quais os cultivos ocorrem de forma constante e sucessiva durante um mesmo ano agrícola. No entanto, isso tem propiciado problemas cada vez mais frequentes relacionados a alguns grupos de pragas, dentre eles os lepidópteros. Espécies como Chrysodeixis includens e o complexo de Spodoptera vem crescendo de importância, causando prejuízos, principalmente em culturas como a soja e o algodoeiro. Dentre os métodos mais utilizados para o controle de insetos-praga no Brasil, destaca-se o uso de OGM, a partir da inserção de genes da bactéria Bacillus thuringiensis (Bt), com expressão de proteínas com ações inseticidas. Entretanto, um dos grandes problemas é a seleção de populações de pragas resistentes aos cultivos Bt devido ao uso contínuo e inadequado da tecnologia. Diante disso, os objetivos do presente estudo foram avaliar os efeitos de cultivares Bt de soja e algodoeiro, que expressam proteínas inseticidas Cry, sobre os aspectos biológicos de C. includens em laboratório, como também avaliar a dinâmica populacional e a infestação natural de lagartas de C. includens e de Spodoptera spp. em condições de campo, no estado do Mato Grosso. Para o estudo dos aspectos biológicos, utilizou-se lagartas neonatas que foram alimentadas com folhas das cultivares de soja e algodoeiro não Bt e Bt de diferentes tecnologias. Os experimentos de campo foram realizados em área experimental do IMAmt na safra 2016/2017, ut... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The agricultural scenario in the brazilian midwest counts on the socalled production systems, in which crops occur constantly and successively during the same agricultural year. However, this has caused increasingly frequent problems related to some groups of pests, among them the Lepidoptera. Species such as Chrysodeixis includens and the Spodoptera complex have been increasing in importance, causing damage, especially in crops such as soybean and cotton. Among the most used methods for the control of insect pests in Brazil, the use of GMOs, from the insertion of genes of the bacterium Bacillus thuringiensis (Bt), with expression of proteins with insecticidal actions, stands out. However, one of the major problems is the selection of populations of pests resistant to Bt crops due to the continuous and inadequate use of the technology. The objectives of the present study were to evaluate the effects of Bt cultivars of soybean and cotton, which express insecticidal Cry proteins, on the biological aspects of C. includens in the laboratory, as well as to evaluate the population dynamics and the natural infestation of caterpillars C. includens and Spodoptera spp. under field conditions, in the state of Mato Grosso. For the study of the biological aspects, we used caterpillars that were fed with leaves of the cultivars of soybean and non-Bt and Bt cotton of different technologies. Field experiments were carried out in the experimental area of the IMAmt in the 2016/2017 season, usi... (Complete abstract click electronic access below) / Doutor

Wang Jian Bin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 117-131). / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.x / Chapter PART I. --- GENERAL INTRODUCTION --- p.4 / Chapter PART II. --- LITERATURE REVIEW --- p.6 / Chapter A. --- The structure and functions of insect Malpighian tubules --- p.6 / Chapter I. --- The excretory system of insects --- p.6 / Chapter 1. --- Morphology of Malpighian tubules --- p.6 / Chapter 2. --- Common types of Malpighian tubule system --- p.7 / Chapter 3. --- Morphology of hindgut --- p.8 / Chapter II. --- Structure of insect Malpighian tubules --- p.9 / Chapter 1. --- General organization of the Malpighian tubules --- p.9 / Chapter 2. --- Structure of the principal cell --- p.10 / Chapter 3. --- The structure of other cell types --- p.14 / Chapter 4. --- The cryptonephridial systems in larvae of Lepidoptera and Coleoptera --- p.16 / Chapter III. --- Functions of insect Malpighian tubules --- p.18 / Chapter 1. --- Mechanism of fluid secretion by Malpighian tubules --- p.18 / Chapter 1.1. --- Ion transport --- p.18 / Chapter 1.2. --- Fluid transport --- p.19 / Chapter 2. --- Active transport of organic compounds by Malpighian tubules --- p.19 / Chapter 2.1. --- Organic anions --- p.19 / Chapter 2.2. --- Organic cations --- p.20 / Chapter 3. --- Resporptive processes in Malpighian tubules --- p.20 / Chapter 3.1. --- KC1 resorption --- p.20 / Chapter 3.2. --- Reabsorption of sugars --- p.21 / Chapter 4. --- The passive permeability of Malpighian tubules --- p.21 / Chapter B. --- The biology and mode of action of Bacillus thuringiensis --- p.23 / Chapter I. --- Introduction --- p.23 / Chapter II. --- Background --- p.23 / Chapter III. --- "Cytology of germination, outgrowth and sporulation" --- p.24 / Chapter IV. --- Bacillus thuringiensis and its toxins --- p.26 / Chapter V. --- Histopathological effects of Bacillus thuringiensis δ-endotoxin on Lepidopterous larva --- p.29 / Chapter VI. --- Mode of action of Bacillus thuringiensis δ-endotoxin --- p.32 / Chapter C. --- The biology and pathological effects of microsporidian protozoa --- p.36 / Chapter I. --- Life cycle of microsporidian protozoa --- p.36 / Chapter II. --- Germination of microsporidian protozoa --- p.37 / Chapter III. --- The fine structure of microsporidian protozoa --- p.38 / Chapter IV. --- Mass production and storage --- p.42 / Chapter V. --- Pathology of microsporidian protozoa --- p.44 / Chapter PART III. --- LIGHT AND ELECTRON MICROSCOPIC STUDIES OF THE MALPIGHIAN TUBULES OF PIERIS CANIDIA LARVA (LEPIDOPTERA) --- p.48 / Summary --- p.48 / Introduction --- p.48 / Materials and methods --- p.49 / Results --- p.50 / Discussion --- p.53 / Chapter PART IV. --- HISTOCHEMICAL STUDIES ON THE PIERIS CANIDIA LARVAL MALPIGHIAN TUBULES --- p.58 / Summary --- p.58 / Introduction --- p.59 / Materials and methods --- p.60 / Results --- p.52 / Discussion --- p.66 / Chapter PART V. --- SEPARATION AND PURIFICATION OF PARASPORAL CRYSTALS OF BACILLUS THURINGIENSIS VAR. KURSTAKI --- p.70 / Summary --- p.70 / Introduction --- p.70 / Materials and methods --- p.74 / Results --- p.77 / Discussion --- p.77 / Chapter PART VI. --- HISTOPATHOLOGICAL EFFECTS OF BACILLUS THURINGIENSIS VAR. KURSTAKI δ-ENDOTOXIN ON THE MALPIGHIAN TUBULES OF PIERIS CANIDIA LARVA --- p.79 / Summary --- p.79 / Introduction --- p.79 / Materials and methods --- p.81 / Results --- p.83 / Discussion --- p.86 / Chapter PART VII. --- THE FINE STRUCTURE OF A MICROSPORIDIAN NOSEMA POLYVORA FROM CABBAGE WHITE PIERIS CANIDIA --- p.92 / Summary --- p.92 / Introduction --- p.92 / Materials and methods --- p.94 / Results --- p.94 / Discussion --- p.97 / Chapter PART VIII. --- HISTOPATHOLOGICAL EFFECTS OF NOSEMA POLYVORA ON THE MALPIGHIAN TUBULES OF PIERIS CANIDIA LARVA --- p.103 / Summary --- p.103 / Introduction --- p.103 / Materials and methods --- p.105 / Results --- p.105 / Discussion --- p.107 / Chapter PART IX. --- GENERAL DISCUSSION --- p.111 / Chapter PART X. --- CONCLUSION AND SUMMARY --- p.115 / REFERENCES --- p.117 / FIGURES AND TABLES --- p.132

Orientador: Janete Apparecida Desidério / Banca: Vivian Boter Bergamasco / Banca: Sonia Marli Zingaretti / Banca: Odair Aprecido Fernandes / Banca: Ana Maria Guidelli Thuler / Resumo: Este trabalho teve como objetivo estudar a toxicidade e a interação entre proteínas Cry1Ab, Cry1Ac, Cry2Aa, Cry2Ab e Vip3Aa em lagartas neonatas de Anticarsia gemmatalis, Chrysodeixis includens e Spodoptera frugiperda. Lisados das proteínas foram utilizados em bioensaios com lagartas neonatas para determinar a CL50 e CL90 das proteínas Cry1Ab, Cry1Ac, Cry2Aa, Cry2Ab e Vip3Aa e realizar experimentos histopatológicos. Ensaios de competição, entre as proteínas Cry1, Cry2 e Vip3 biotiniladas, foram realizados com as proteínas das vesículas de membrana da microvilosidade apical do intestino médio ("Brush Border Membrane Vesicles" - BBMV) das lagartas. Foi feita a purificação de receptores para toxina Cry1Ac a partir da BBMV de A. gemmatalis e C. includens por afinidade seguida da identificação das proteínas ligantes. As toxinas Cry1A e Cry2A demonstraram maior toxicidade para A. gemmatalis e C. includens que a proteína Vip3Aa, porém o inverso foi observado em S. frugiperda. As lagartas da espécie A. gemmatalis se mostraram mais suscetíveis as proteínas testadas do que as de S. frugiperda e C. includens. As espécies diferiram também quanto ao tipo de interação entre as toxinas. Enquanto para S. frugiperda e C. includens, as interações foram sinérgicas, para A. gemmatalis foram predominantemente antagônicas. As proteínas se uniram aos receptores presentes nas BBMV de S. frugiperda, A. gemmatalis e C. includens, permitindo inferir sobre a presença e ausência de comp... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aimed to study the toxicity and interaction between Cry1Ab, Cry1Ac, Cry2Aa, Cry2Ab and Vip3Aa proteins in neonate larvae of Spodoptera frugiperda, Anticarsia gemmatalis and Chrysodeixis includens. Lysates containing proteins were used in bioassays for the determination of LC50 and LC90 of the Cry1Ab, Cry1Ac, Cry2Aa, Cry2Ab and Vip3Aa proteins. Histopathological experiments were realized with A. gemmatalis, C. includens (fed with Cry1Ac and Vip3Aa) and S frugiperda (fed with Cry1Ab and Vip3Aa). Competition assays, among biotinylated Cry1, Cry2 and Vip3 proteins, were performed with brush border membrane vesicles (BBMV) proteins from A. gemmatalis, C. includens and S. frugiperda. Purification of Cry1Ac receptors from A. gemmatalis and C. includens BBMV was performed by affinity followed by identification of binding proteins. The Cry1A and Cry2A toxins demonstrated higher toxicity to A. gemmatalis and C. includens than the Vip3Aa protein, but the inverse was observed to S. frugiperda. A. gemmatalis larvae were more susceptible as Cry and Vip proteins than as S. frugiperda and C. includens. Species differed about type of protoxins interaction. While for S. frugiperda and C. includens, the protoxins showed as synergistic interactions, for A. gemmatalis they were predominantly antagonistic. It was possible to infer about presence and absence of competition of the receptors in the BBMV from S. frugiperda, A. gemmatalis and C. includens. Histopathological changes as vacuolization and disruption were observed in the intestine from S. frugiperda larvae, fed with Cry1Ab and Vip3Aa and A. gemmatalis and C. includens, fed with Cry1Ac and Vip3Aa. Putative receptors were to identified from A. gemmatalis and C. includens to Cry1Ac toxin. The combination of Cry and Vip proteins, as well as helping to manage resistance and can increase toxicity through synergistic acti... (Complete abstract electronic access below) / Doutor

Orientador: Marcelo da Costa Ferreira / Banca: Otavio Jorge Grigoli Abi Saab / Banca: Arlindo Leal Boiça Junior / Banca: Hamilton Humberto Ramos / Banca: Raphael de Campos Castilho / Resumo: Tendo em vista, manter as populações de pragas em densidades baixas, táticas de controle são adotadas como alternativas para manter a viabilidade econômica. O uso de inseticidas é uma das práticas mais utilizadas na agricultura para o controle de insetos-praga, porém, os bioinseticidas à base de Bt, tem sido utilizado como complemento ao controle químico, assim como a adição de aditivos, como os adjuvantes e o Silício (Si). Neste sentido, o objetivo do trabalho foi avaliar o efeito do controle das lagartas desfolhadoras na cultura da soja com inseticida químico, biológico e sua mistura, combinados ou não a aditivos (silicio foliar e óleo mineral). Experimentos foram conduzidos no Núcleo de Estudo e Desenvolvimento em Tecnologia de Aplicação - NEDTA da UNESP, Câmpus de Jaboticabal. Os tratamentos avaliados foram, inseticidas químico e biológico, isolados ou associados ao adjuvante e silício foliar. Os fatores de estudo foram depósito, cobertura e caracterização de gotas, tensão superficial, ãngulo de contato, mortalidade das lepidópeteras e produtividade da cultura. A combinação entre o inseticida químico (indoxacarbe) e o biológico (Bacillus thuringiensis) com ou sem aditivos, reduziu a tensão superficial, alterou o ângulo de contato, diminuiu a % de gotas < 100 μm e o SPAN. E comprometeu a eficiência de controle da H. armigera, a adição de aditivos promoveram efeitos positivos na eficiência de controle da lagarta. O terço superior da planta recebeu maior depósito e cobertura... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In order to keep pests in low densities, control tactics are adopted as alternatives to maintain economic viability. The use of insecticides is one of the most used practices in agriculture for the control of insect pests. However, Bt-based bio-insecticides have been used as a complement to chemical control. As well as the addition of additives such as adjuvants and Silicon (Si). In this sense, the objective of this work was to evaluate the effect of the control of leafhopper caterpillars on the soybean crop with chemical and biological insecticide and its mixture, combined or not with additives (foliar fertilizer and adjuvant). Experiments were conducted at the Phytosanitary Treatment Laboratory at the Nucleus of Study and Development in Application Technology - NEDTA of UNESP, Câmpus de Jaboticabal. The evaluated treatments were chemical and biological insecticides, isolated or associated to the adjuvant and foliar silicon. The study factors were deposition, coverage and characterization of droplets, surface tension, contact angle, lepidoptera mortality and crop productivity. The combination of the chemical insecticide (indoxacarb) and the biological insecticide (Bacillus thuringiensis) with or without the additives reduced surface tension, altered the angle of, decreased droplets <100 μm and SPAN compromised control efficiency. H. armigera, the addition of additives promoted positive effects on the control efficiency of. The upper third of the plant received greater deposi... (Complete abstract click electronic access below) / Doutor

Submitted by JACOB CROSARIOL NETTO Crosariol Netto (jacob_netto@hotmail.com) on 2017-02-24T21:47:39Z No. of bitstreams: 1 Tese_Jacob_Crosariol_Netto.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-03-06T17:33:34Z (GMT) No. of bitstreams: 1 crosariolnetto_j_dr_jabo.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) / Made available in DSpace on 2017-03-06T17:33:34Z (GMT). No. of bitstreams: 1 crosariolnetto_j_dr_jabo.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) Previous issue date: 2017-01-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The fall armyworm Spodoptera frugiperda is the major pest of corn in tropical and subtropical regions in the American Continent. Among the most used methods to control this pest in Brazil, it highlights the use of genetically modified plants from the insertion of a Bacillus thuringiensis gene that confers to the plant the expression of proteins with insecticidal actions. However, after two or three years these technologies reduce the degree of suppression of larvae, mainly due to the continuous and inadequate use of the technology. The objective of this work was to study in field conditions, the behavior of Bt corn hybrids against lepidopteran attacks as S. frugiperda and Helicoverpa zea in four corn-producing regions of São Paulo State, as well as to study in laboratory conditions the comparative biology of populations of S. frugiperda collected in these regions. Field experiments were carried out during the second corn season in 2014 in the regions of Médio Paranapanema, Centro Norte, Noroeste and Norte of São Paulo State where were used 25 corn cultivars with the expression of different insecticidal proteins. To the comparative biology study, the larvae were collected in the four regions of the state, the larvae were sent to Integrated Pest Management Laboratory of FCAV-Unesp where the experiments were carried out with leaves of corn hybrids of different technologies. The results of field experiments demonstrate that the insecticidal protein VIP3Aa20 presents a high level of suppression on the populations of S. frugiperda and H. zea, in addition, the corn hybrids that express the insecticidal protein Cry1F were the most susceptible against the attack of these two pests. Through the results obtained from the experiments of comparative biology, it was verified that the insecticidal protein VIP3Aa20 provided 100% of mortality of larvae from the four regions. The hybrid with expression of the proteins Cry1A.105 + Cry2Ab2 + Cry1F was the one that provided low viability of S. frugiperda larvae coming from the four regions of the São Paulo State. The hybrid that expresses the insecticidal protein Cry1F provided low levels of suppression as well as low adverse effects in the development of S. frugiperda coming from the four regions of the state, indicating that the populations present in these four regions are resistant to the action of this insecticidal protein. / A lagarta do cartucho Spodoptera frugiperda é a principal praga da cultura do milho nas regiões tropicais e subtropicais do continente americano. Dentre os métodos mais utilizados para o controle desta praga no Brasil, destaca-se o uso de plantas geneticamente modificadas a partir da inserção de um gene da bactéria Bacillus thuringiensis que confere a planta a expressão de proteínas com ações inseticidas. No entanto, durante dois ou três anos estas tecnologias reduziram o grau de supressão às lagartas, principalmente pelo uso continuo e inadequado da tecnologia. O objetivo deste trabalho foi estudar em condições de campo, o comportamento de híbridos de milho Bt frente ao ataque de lepidópteros, como a S. frugiperda e Helicoverpa zea, em quatro regiões produtoras de milho do estado de São Paulo, bem como estudar em condições de laboratório a biologia comparada de populações de S. frugiperda coletadas nestas regiões. Os experimentos de campo foram realizados no período da segunda safra de milho, no ano de 2014, nas regiões do Médio Paranapanema, Centro Norte, Noroeste e Norte do estado de São Paulo, onde foram utilizados 25 cultivares de milho com expressão de diferentes proteínas inseticidas. Para o estudo de biologia comparada foi realizada a coleta de lagartas nas quatro regiões do estado, as lagartas foram enviadas ao laboratório de Manejo Integrado de Pragas da FCAV-Unesp onde foram realizados os experimentos com folhas de híbridos de milho de diferentes tecnologias. Os resultados dos experimentos realizados a campo demonstram que a proteína inseticida VIP3Aa20 apresenta alto nível de supressão sobre as populações de S. frugiperda e Helicoverpa zea, além disso, os híbridos de milho que expressam a proteína inseticida Cry1F foram os mais suscetíveis frente ao ataque destas duas pragas. Através dos resultados obtidos para os experimentos de biologia comparada, constatou-se que a proteína inseticida VIP3Aa20 proporcionou 100% de mortalidade das lagartas oriundas das quatro regiões. O híbrido com expressão das proteínas Cry1A.105 + Cry2Ab2 + Cry1F foi o que proporcionou menor viabilidade de lagartas de S. frugiperda oriundas das quatro regiões do estado. O híbrido que expressa a proteína inseticida Cry1F proporcionou baixos níveis de supressão além de baixos efeitos adversos no desenvolvimento de S. frugiperda oriundas das quatro regiões do estado, indicando que as populações presentes nestas quatro regiões se encontram resistentes a ação desta proteína inseticida.