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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.
11

Adubação com enxofre, nitrogênio, cálcio e potássio afetando a interação entre Tuta absoluta e o tomateiro / Fertilization with sulfur, nitrogen, potassium and calcium affect the interaction between tomato and Tuta absoluta

Queiroz, Renan Batista 21 February 2011 (has links)
Made available in DSpace on 2015-03-26T13:30:32Z (GMT). No. of bitstreams: 1 texto completo.pdf: 107354 bytes, checksum: f8bf4d4e5a1424ff9f074f4c658d674e (MD5) Previous issue date: 2011-02-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The nutrients used for plant fertilization affect their susceptibility to insect herbivores. Among the major pests of tomato in the world is a leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). Thus, the aim of this study was to determine the influence of plant fertilization with calcium, sulfur, nitrogen and potassium in reproduction, growth, survival and damage of T. absoluta. This study was conducted in a greenhouse. The experimental design was randomized blocks with nine treatments and five replications. The treatments consisted of fertilization levels of deficiency and excess calcium, sulfur, nitrogen and potassium. One treatment with normal fertilization was established beyond these levels. The eggs from T. absoluta were transferred for the leaves of tomato a month after the start of the experiment. The number of surviving insects, the developmental stage of insects and the number of mines per leaf were evaluated daily. The contents of nutrients were determined in leaves of tomato. Among the nutrients studied, only the doses of sulfur and nitrogen fertilizer used in the affected T. absoluta. The reproduction of T. absoluta was lower in plants with normal fertilization, higher the mortality of larvae and these plants suffered less damage than those with nutritional deficiency. The maximum reproductive performance of T. absoluta occurred in plants with nutritional deficiency. The plants with higher levels of nutrients in leaves were less susceptible to T. absoluta. / Os nutrientes utilizados na adubação das plantas afetam sua suscetibilidade aos insetos herbívoros. Entre as principais pragas do tomateiro no mundo está a traça Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). Assim, o objetivo deste trabalho foi determinar a influência da adubação das plantas com cálcio, enxofre, nitrogênio e potássio na reprodução, desenvolvimento, sobrevivência e danos de T. absoluta. Este trabalho foi conduzido em casa de vegetação. O delineamento experimental foi em blocos casualizados com nove tratamentos e cinco repetições. Os tratamentos foram constituídos de níveis de adubação em deficiência e em excesso de cálcio, enxofre, nitrogênio e potássio. Além destes níveis estabeleceu-se um tratamento com adubação normal. Um mês após o início do experimento, foram transferidos ovos de T. absoluta para as folhas do tomateiro. Diariamente avaliaram-se o número de insetos sobreviventes, o estádio de desenvolvimento dos insetos e o número de minas por folha. Foram determinados os teores de nutrientes nas folhas do tomateiro. Dos nutrientes estudados apenas as doses de enxofre e de nitrogênio usadas na adubação afetaram T. absoluta. Nas plantas com adubação normal foi menor a reprodução de T. absoluta, maior a mortalidade larval e estas plantas sofreram menores danos do que aquelas com deficiência nutricional. O máximo desempenho reprodutivo de T. absoluta ocorreu em plantas com deficiência nutricional. As plantas com maiores teores de nutrientes nas folhas foram menos suscetíveis a T. absoluta.
12

Resistência de variedades de cana-de-açúcar à Cigarrinha-das-raízes Mahanarva fimbriolata (Stål) (Hemiptera, Cercopidae) /

Lima, Larissa Cardoso de. January 2010 (has links)
Resumo: Os intensos ataques de cigarrinha-das-raízes, Mahanarva fimbriolata, ocorridos em cana-de-açúcar, tem causado perdas econômicas expressivas. Devido a novas práticas culturais utilizadas no setor, ou seja, colheita de cana crua, aumentou significativamente a ocorrência e os danos provocados por esta praga na cultura. O trabalho foi conduzido em casa-de-vegetação e no Laboratório do Centro APTA - Cana-de-Açúcar do Instituto Agronômico, Ribeirão Preto-SP e teve por objetivos estudar a densidade adequada de adultos com o propósito de obter uma infestação suficiente para discriminação de variedades de cana- de-açúcar e a idade mais adequada da planta visando à realização de ensaios de resistência à cigarrinha-das-raízes; discriminar as variedades de cana-de-açúcar de importância econômica quanto à resistência de plantas a insetos de acordo com a excreção, atratividade, a não- preferência com e sem chance de escolha, a antibiose da cigarrinha-das-raízes e assim fornecer uma ferramenta a mais no manejo e controle dessa praga. Pela análise dos resultados conclui-se que M. fimbriolata prefere ovipositar em plantas com 25 e 35 dias de idade e, nas densidades de 2 a 5 casais por planta, depositaram número suficiente de ovos para diferenciar variedades de cana-de-açúcar após 48 horas da infestação. Na variedade SP80-1842, M. fimbriolata produziu uma maior quantidade de excreção em relação à variedade SP83-5073. As variedades RB83-5486, RB72-454 e SP80-1842 foram mais atrativas à cigarrinha-das- raízes que IACSP87-3396 e SP83-5073. Quanto à preferência para oviposição, SP83-5073, em teste com e sem chance de escolha, apresentou menor oviposição por M. fimbriolata. Ao analisar todos os parâmetros biológicos, constatou-se que a variedade SP80-1842 apresenta suscetibilidade a M. fimbriolata. As variedades SP83-5073 e IAC87-3396 determinaram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The sugarcane spittlebug Mahanarva fimbriolata has inflicted intense attacks on sugarcane, resulting in expressive economic losses. Due to the new cultural practice of green harvest (mechanical), occurrence and damage by the spittlebug have increased significantly. This research was conducted in a greenhouse and at the laboratory of the "Centro APTA- Cana-de-Açúcar" in Ribeirão Preto, state of São Paulo, Brazil. The objectives were to study the adequate adult density to conduct experiments to ascertain which were the best age and varieties of sugarcane to be utilized in tests of resistence to the spittlebug; to discriminate economically important sugarcane varieties when checked for resistance to the spittlebug in trials of excretion, attraction, non-preference (choice and no-choice) and antibiosis. Results showed that the spittlebug preferred to oviposit in 25-35 days old plants, and at the density between 2-5 couples/plant it laid sufficient eggs to differentiate sugarcane varieties after 48 h of infestation. The spittlebug excreted more when fed on variety SP80-1842, when compared to variety SP83-5073. The varieties RB83-5486, RB72-454 and SP80-1842 were more attractive to the spittlebug than varieties IACSP87-3396 and SP83-5073. In trials with choice and no-choice, the spittlebug laid less eggs on variety SP83-5073. After analyzing all biological parameters, concluded that variety SP80-1842 showed susceptibility to the spittlebug. When fed on the varieties SP83-5073 and IAC87-3396 the spittlebug displayed the highest duration of incubation period, nymphal period and mortality, while the oviposition period and longevity of males and females shortened and fecundity dropped; antibiosis was the primary cause of resistance. / Orientador: Geraldo Papa / Coorientador: Leila Luci Dinardo-Miranda / Banca: Carlos Alberto Hector Flechtmann / Banca: Sérgio Luís de Carvalho / Banca: Adalton Raga / Banca: Mário Eidi Sato / Doutor
13

Resistência de genótipos de tomateiro ao ataque de Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae)

Bottega, Daline Benites [UNESP] 25 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T19:52:55Z : No. of bitstreams: 1 bottega_db_me_jabo.pdf: 449576 bytes, checksum: 2bd868a8995069f54faa80c8094e355d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se com este trabalho avaliar possíveis fontes de resistência de genótipos de tomateiro a Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), dos tipos não preferência, para oviposição, alimentação e antibiose, em avaliações de parâmetros biológicos das fases jovem e adulta do inseto. Os experimentos foram realizados no Laboratório de Resistência de Plantas a Insetos, do Departamento de Fitossanidade da Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal-SP. As espécies de tomateiro utilizadas foram Lycopersicon esculentum (Mill.) (cv. Santa Clara, cinco híbridos: Saladete Italiano Ty Tyna, Santa Cruz Débora Ty, Salada Lumi, Saladete Italiano Andrea Victory e Santa Cruz Ty Carina Ty), Lycopersicon hirsutum f. glabratum (C.H. Mull.) (linhagens PI 134418 e PI 134417) e Lycopersicon pimpinellifolium (Just) (linhagens NAV 1062 e PI 126931), para os testes de não preferência para oviposição e alimentação, e todos esses materiais, menos Santa Cruz Ty Carina Ty, para o teste de antibiose. Para os testes de não preferência para oviposição, avaliou-se o número de ovos às 24; 48 e 72 horas após a liberação dos adultos. Os testes de não preferência para alimentação foram realizados com e sem chance de escolha, utilizando lagartas de 12 dias de idade. As avaliações foram realizadas aos 1; 3; 5; 10; 30; 60; 120; 360; 720 e 1440 minutos após a liberação das lagartas, contando o número de indivíduos alimentando-se por genótipo, e quantificando, ao término do experimento, a massa foliar consumida por genótipo. Constatou-se que os genótipos de tomateiro... / The objective of this study was to evaluate possible sources of resistance of tomato genotypes to Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), types of non preference for oviposition, feeding and antibiosis in evaluations of biological parameters of the stages and young adult insect. The experiments were performed at the Laboratory of Plant Resistance to Insects, Department of Plant Protection, Faculty of Agriculture and Veterinary Sciences, Jaboticabal-SP. The species used were tomato Lycopersicon esculentum (Mill.) (cv. Santa Clara, five hybrids: Saladete Italian Ty Tyna, Santa Cruz Débora Ty, Salad Lumi, Saladete Italian Andrea Victory and Santa Cruz Ty Carina Ty), Lycopersicon hirsutum f. glabratum (CH Mull.) (lines PI 134418 and PI 134417) and Lycopersicon pimpinellifolium (Just) (lines NAV 1062 and PI 126931), tests for non preference for oviposition and feeding, and all these materials, less Santa Cruz Ty Carina Ty, to test antibiosis. For testing non preference for oviposition, we evaluated the number of eggs at 24, 48 and 72 hours after the release of adults. Tests of non preference for feeding were performed with and without choice, using larvae of 12 days of age. Evaluations were performed at 1; 3; 5; 10; 30; 60; 120; 360; 720 and 1440 minutes after the release of the caterpillars, counting the number of individuals feeding on the genotype, and quantifying the end the experiment, the leaf mass consumed by genotype. It was found that the tomato genotypes evaluated did not show resistance type non preference for oviposition. Since PI 134417 showed resistance of the non-feeding preference. The antibiosis test, were performed 20 repetitions with 3 larvae each. The parameters were: duration and viability of larval and pupal, duration and survival of the caterpillars hatch to adult emergence (total), longevity of unfed adults, weight of pupae with 24 hours of age and ... (Complete abstract click electronic access below)
14

Resistência de variedades de cana-de-açúcar à Cigarrinha-das-raízes Mahanarva fimbriolata (Stål) (Hemiptera, Cercopidae)

Lima, Larissa Cardoso de [UNESP] 26 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-26Bitstream added on 2014-06-13T19:24:50Z : No. of bitstreams: 1 lima_lc_dr_ilha.pdf: 971910 bytes, checksum: fb99b31c387943da7c35413238434f36 (MD5) / Os intensos ataques de cigarrinha-das-raízes, Mahanarva fimbriolata, ocorridos em cana-de-açúcar, tem causado perdas econômicas expressivas. Devido a novas práticas culturais utilizadas no setor, ou seja, colheita de cana crua, aumentou significativamente a ocorrência e os danos provocados por esta praga na cultura. O trabalho foi conduzido em casa-de-vegetação e no Laboratório do Centro APTA - Cana-de-Açúcar do Instituto Agronômico, Ribeirão Preto-SP e teve por objetivos estudar a densidade adequada de adultos com o propósito de obter uma infestação suficiente para discriminação de variedades de cana- de-açúcar e a idade mais adequada da planta visando à realização de ensaios de resistência à cigarrinha-das-raízes; discriminar as variedades de cana-de-açúcar de importância econômica quanto à resistência de plantas a insetos de acordo com a excreção, atratividade, a não- preferência com e sem chance de escolha, a antibiose da cigarrinha-das-raízes e assim fornecer uma ferramenta a mais no manejo e controle dessa praga. Pela análise dos resultados conclui-se que M. fimbriolata prefere ovipositar em plantas com 25 e 35 dias de idade e, nas densidades de 2 a 5 casais por planta, depositaram número suficiente de ovos para diferenciar variedades de cana-de-açúcar após 48 horas da infestação. Na variedade SP80-1842, M. fimbriolata produziu uma maior quantidade de excreção em relação à variedade SP83-5073. As variedades RB83-5486, RB72-454 e SP80-1842 foram mais atrativas à cigarrinha-das- raízes que IACSP87-3396 e SP83-5073. Quanto à preferência para oviposição, SP83-5073, em teste com e sem chance de escolha, apresentou menor oviposição por M. fimbriolata. Ao analisar todos os parâmetros biológicos, constatou-se que a variedade SP80-1842 apresenta suscetibilidade a M. fimbriolata. As variedades SP83-5073 e IAC87-3396 determinaram... / The sugarcane spittlebug Mahanarva fimbriolata has inflicted intense attacks on sugarcane, resulting in expressive economic losses. Due to the new cultural practice of green harvest (mechanical), occurrence and damage by the spittlebug have increased significantly. This research was conducted in a greenhouse and at the laboratory of the “Centro APTA- Cana-de-Açúcar” in Ribeirão Preto, state of São Paulo, Brazil. The objectives were to study the adequate adult density to conduct experiments to ascertain which were the best age and varieties of sugarcane to be utilized in tests of resistence to the spittlebug; to discriminate economically important sugarcane varieties when checked for resistance to the spittlebug in trials of excretion, attraction, non-preference (choice and no-choice) and antibiosis. Results showed that the spittlebug preferred to oviposit in 25-35 days old plants, and at the density between 2-5 couples/plant it laid sufficient eggs to differentiate sugarcane varieties after 48 h of infestation. The spittlebug excreted more when fed on variety SP80-1842, when compared to variety SP83-5073. The varieties RB83-5486, RB72-454 and SP80-1842 were more attractive to the spittlebug than varieties IACSP87-3396 and SP83-5073. In trials with choice and no-choice, the spittlebug laid less eggs on variety SP83-5073. After analyzing all biological parameters, concluded that variety SP80-1842 showed susceptibility to the spittlebug. When fed on the varieties SP83-5073 and IAC87-3396 the spittlebug displayed the highest duration of incubation period, nymphal period and mortality, while the oviposition period and longevity of males and females shortened and fecundity dropped; antibiosis was the primary cause of resistance.
15

Resistência de genótipos de tomateiro ao ataque de Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) /

Bottega, Daline Benites. January 2010 (has links)
Resumo: Objetivou-se com este trabalho avaliar possíveis fontes de resistência de genótipos de tomateiro a Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), dos tipos não preferência, para oviposição, alimentação e antibiose, em avaliações de parâmetros biológicos das fases jovem e adulta do inseto. Os experimentos foram realizados no Laboratório de Resistência de Plantas a Insetos, do Departamento de Fitossanidade da Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal-SP. As espécies de tomateiro utilizadas foram Lycopersicon esculentum (Mill.) (cv. Santa Clara, cinco híbridos: Saladete Italiano Ty Tyna, Santa Cruz Débora Ty, Salada Lumi, Saladete Italiano Andrea Victory e Santa Cruz Ty Carina Ty), Lycopersicon hirsutum f. glabratum (C.H. Mull.) (linhagens PI 134418 e PI 134417) e Lycopersicon pimpinellifolium (Just) (linhagens NAV 1062 e PI 126931), para os testes de não preferência para oviposição e alimentação, e todos esses materiais, menos Santa Cruz Ty Carina Ty, para o teste de antibiose. Para os testes de não preferência para oviposição, avaliou-se o número de ovos às 24; 48 e 72 horas após a liberação dos adultos. Os testes de não preferência para alimentação foram realizados com e sem chance de escolha, utilizando lagartas de 12 dias de idade. As avaliações foram realizadas aos 1; 3; 5; 10; 30; 60; 120; 360; 720 e 1440 minutos após a liberação das lagartas, contando o número de indivíduos alimentando-se por genótipo, e quantificando, ao término do experimento, a massa foliar consumida por genótipo. Constatou-se que os genótipos de tomateiro ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate possible sources of resistance of tomato genotypes to Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), types of non preference for oviposition, feeding and antibiosis in evaluations of biological parameters of the stages and young adult insect. The experiments were performed at the Laboratory of Plant Resistance to Insects, Department of Plant Protection, Faculty of Agriculture and Veterinary Sciences, Jaboticabal-SP. The species used were tomato Lycopersicon esculentum (Mill.) (cv. Santa Clara, five hybrids: Saladete Italian Ty Tyna, Santa Cruz Débora Ty, Salad Lumi, Saladete Italian Andrea Victory and Santa Cruz Ty Carina Ty), Lycopersicon hirsutum f. glabratum (CH Mull.) (lines PI 134418 and PI 134417) and Lycopersicon pimpinellifolium (Just) (lines NAV 1062 and PI 126931), tests for non preference for oviposition and feeding, and all these materials, less Santa Cruz Ty Carina Ty, to test antibiosis. For testing non preference for oviposition, we evaluated the number of eggs at 24, 48 and 72 hours after the release of adults. Tests of non preference for feeding were performed with and without choice, using larvae of 12 days of age. Evaluations were performed at 1; 3; 5; 10; 30; 60; 120; 360; 720 and 1440 minutes after the release of the caterpillars, counting the number of individuals feeding on the genotype, and quantifying the end the experiment, the leaf mass consumed by genotype. It was found that the tomato genotypes evaluated did not show resistance type non preference for oviposition. Since PI 134417 showed resistance of the non-feeding preference. The antibiosis test, were performed 20 repetitions with 3 larvae each. The parameters were: duration and viability of larval and pupal, duration and survival of the caterpillars hatch to adult emergence (total), longevity of unfed adults, weight of pupae with 24 hours of age and ... (Complete abstract click electronic access below) / Orientador: Arlindo Leal Boiça Júnior / Coorientador: André Luiz Lourenção / Banca: Júlio Cesar Galli / Banca: José Roberto Scarpellini / Mestre
16

Efeito da fragmentação florestal no Estado de São Paulo na interação de Ficus eximia Schott e suas vespas associadas / Forest fragmentation effects on the interaction of Ficus eximia Schott and their associated wasps in the state of Sao Paulo

Ludmila Maria Rattis Teixeira 17 February 2011 (has links)
Frente ao intenso processo de fragmentação florestal sofrido no Brasil, este trabalho avaliou o efeito da fragmentação de Florestas Estacionais Semideciduais no Estado de São Paulo sobre a interação Ficus eximia e vespas (polinizadoras e não-polinizadoras). A abordagem foi realizada em duas escalas, (1) Na paisagem, com comparações entre os dados encontrados nas regiões de Teodoro Sampaio (menos fragmentada); Gália (intermediária) e Ribeirão Preto (mais fragmentada); e (2) Na escala local, considerando as características da paisagem no entorno das plantas amostradas. As questões investigadas foram: (a) Existe limitação de pólen em paisagens muito degradadas? (b) A estrutura da comunidade de vespas varia de acordo com o nível de fragmentação e distúrbio dos hábitats? (c) Possíveis limitações de pólen ou parasitismo por vespas não-polinizadoras comprometem os componentes primários de fecundidade das figueiras nas paisagens mais fragmentadas? Para responder tais questões, coletamos figos na fase interfloral (após a entrada da polinizadora e antes da maturação das sementes e prole) e figos em fase próxima à emergência das vespas. Os resultados mostraram que não houve indícios de limitação de vespas polinizadoras em nenhuma das paisagens estudadas. As comunidades apresentaram padrão aninhado, ou seja, a comunidade mais pobre em espécies Teodoro Sampaio representou uma subamostra das comunidades mais ricas Ribeirão Preto e Gália. A disponibilidade de vespas polinizadoras parece ser maior na paisagem mais fragmentada. As vespas parasitas inquilinas afetaram negativamente as produções de sementes e polinizadores em Ribeirão Preto; as vespas galhadoras também afetaram negativamente a produção de sementes em Gália e a produção de sementes e polinizadores em Teodoro Sampaio. No entanto, não foram detectadas, em geral, relações significativas entre as variáveis relacionadas ao potencial reprodutivo das figueiras e as características das paisagens estudadas. O presente estudo mostrou que o mutualismo Ficus-vespas de figo parece ser robusto às alterações da paisagem em escala subcontinental. O sistema reprodutivo alógamo das figueiras, com polinização biótica aprimorada pelo vento torna esse sistema biológico bastante insensível às modificações ambientais em pequena escala. / Brazilian forests, especially in the central and southeast regions, have been subject to intense habitat fragmentation. This study evaluated the fragmentation effects of semideciduous seasonal forests in São Paulo on the interaction between Ficus eximia and associated wasps (pollinating and non-pollinating). Our approach comprised two scales: (1) landscape scale, for which we compared data from the studied regions, namely Teodoro Sampaio (less fragmented), Gália (intermediate) and Ribeirão Preto (more fragmented) and (2) local scale, for which we considered the characteristics of the surrounding landscape of the sampled plant. The investigated issues were the following: (a) Is there pollen limitation in greatly degraded landscapes? (b) Does wasp community structure vary with fragmentation level and habitat disturbance? (c) Is it possible that limitations of pollen or parasitism by nonpollinating wasps compromise the primary fertility components of fig trees in the more fragmented landscape? To answer these questions, we collected figs at interfloral phase (after the pollinator had entered the fig and before offspring and seeds had completed their development) and figs close to wasp emergence phase. The results showed no evidence of pollination limitation in any studied landscape. The communities had a nested pattern, i.e., the species-poorest community Teodoro Sampaio is a subsample of the richer communities Ribeirão Preto and Gália. The availability of pollinating wasps appears to be greater in more fragmented landscapes. Inquiline fig wasps negatively affected seed and pollinator production in Ribeirão Preto; galler wasps also negatively affected seed production in Gália and seed and pollinator production in Teodoro Sampaio. However, significant relationships between variables related to fig reproductive potential and landscape characteristics were generally not detected. This study showed that Ficus-fig wasp mutualism appears to be resistant to landscape changes on a subcontinental scale. The reproductive system of fig biotic pollination enhanced by the wind makes this biological system rather insensitive to small-scale environmental changes.
17

Estímulos olfativos envolvidos na busca hospedeira por larvas de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) em milho / Olfactory stimuli associated with host search by Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) in corn

Franciele dos Santos 02 September 2013 (has links)
Apesar da importância dos herbívoros de solo na estruturação da comunidade e também como pragas agrícolas, nosso entendimento sobre a ecologia química de suas interações com a planta hospedeira é limitado comparado à vasta literatura sobre os herbívoros que se alimentam de órgãos aéreos das plantas. O presente estudo teve como objetivo identificar os estímulos olfativos envolvidos na busca hospedeira de Diabrotica speciosa. Larvas de 1º. ínstar de D. speciosa foram capazes de localizar plantas hospedeiras de milho, mas sem distinguir plantas não induzidas das induzidas pela herbivoria radicular e/ou foliar. Já larvas de 2º e 3º ínstar apresentaram preferência por plantas sem indução frente a plantas induzidas pela herbivoria radicular. No entanto, estas larvas preferiram plantas induzidas pela herbivoria foliar em detrimento a plantas sem indução. Na situação em que plantas sem indução foram confrontadas com plantas induzidas pela herbivoria foliar + radicular não houve preferência destas larvas. A análise do perfil de voláteis juntamente com o PCA (\'Análise dos Componentes Principais\') revelaram semelhança entre os voláteis emitidos por plantas induzidas pela herbivoria radicular e foliar + radicular, bem como entre plantas sem indução e induzidas pela herbivoria foliar. Estas diferenças nos perfis de voláteis não foram suficientes para explicar o comportamento de busca hospedeira de larvas de 2º e 3º ínstar, sugerindo a possibilidade de outras pistas químicas associadas com a busca hospedeira de larvas de D. speciosa. / Despite the importance of soil herbivores in community structure and their status as pests, our understanding about the chemical ecology of their interactions is still limited compared to the vast literature on aboveground herbivores. The current study aimed at identifying the olfactory stimuli used in host search by Diabrotica speciosa. First-instar larvae of D. speciosa were able to find corn host plants; however, they did not distinguish between herbivore-induced and non-induced plants (control). Second-and-third-instar larvae preferred non-induced over root-herbivore induced plants. Nevertheless, second-and-third-instar larvae preferred leaf-herbivore induced plants, inflicted by D. speciosa adults, over non-induced plants. When larvae were exposed to non-induced and leaf + root-herbivore induced plants, they did not show preference. Volatile profile analysis together with PCA (Principal Component Analysis) revealed similarity between volatiles emitted by root-herbivore induced and leaf + root-herbivore induced plants as well as between non-induced and leaf-herbivore induced plants. These differences in plant volatile profile were not sufficient to explain host search behavior of second-and-third instar larvae, suggesting the possibility of other chemical cues are associated with host search of D. speciosa larvae.
18

Sistemática e biogeografia de besouros curculionídeos (Curculionoidea; Coleoptera) associados a figueiras (Ficus; Moracae) / Sistemática e Biogeografia de Besouros Curculionídeos (Curculionoidea; Coleoptera) associados a figueiras (Ficus; Moraceae).

Luciano Palmieri Rocha 19 May 2017 (has links)
Among the number of examples of broad radiations of insects on plants, the fig fig wasp system is one of the most remarkable. Although this interaction has frequently been used as a model for studies of mutualism and coevolution, other groups of insects associated with fig trees have received less attention. The weevils (Coleoptera: Curculionidae) associated with figs are one notable example. Being the largest family of animals, weevils achieved great evolutionary success due to their early association with their host plants. Despite few reports in literature, there is strong evidence of the specialization of weevils on figs. The main objective of this thesis was to understand how diversification of Curculionidae took place in fig trees. Previous studies have never addressed the systematics and biogeography of fig weevils under a phylogenetic framework. Therefore, we analyzed the tempo of diversification of Curculionidae lineages that use fig trees as host in order to reconstruct their historical biogeography. To gather information on fig weevils, we collected 325 fruit sets from more than 12% of the total Ficus species, from the Neotropical, Afrotropical and Oriental regions. We also examined seven entomological collections (AMNH, BMNH, INBIO, MNHN, MZUSP, NMNH, SAMC) searching for weevil specimens collected on figs. At least 80 weevil species from five genera (Cetatopus, Omophorus, Carponinus, Curculio, and Indocurculio) were found to be associated with figs. The radiation of curculionids on figs occurred at least three times independently. The tempo of diversification of the crown fig weevils is congruent with the diversification of figs during the Upper-Cretaceous/Lower-Eocene period. We hypothesize that the variation of the sea level and warmer climate in the past had great influence on the evolution of the species. Our results encourage future research on the biology and ecology of these species and will help us to understand the role weevils may have played in the evolution of the fig- fig wasp mutualism. / Um dos mais notáveis exemplos de radiação adaptativa de insetos em classes de plantas é o sistema figueiras - vespas de figo. Embora essa interação tenha sido frequentemente usada como modelo nos estudos de mutualismo e coevolução, outros grupos de insetos relacionados às figueiras têm sido negligenciados. Besouros curculionídeos (Coleoptera: Curculionidae) associados a figueiras representam um desses grupos pouco estudados. Apesar dos relatos escassos na literatura, existem fortes evidências do alto grau de especialização destes besouros às suas plantas hospedeiras. O objetivo geral desta tese foi entender como se deu a diversificação dos curculionídeos sobre as figueiras. Trabalhos anteriores nunca utilizaram uma abordagem filogenética para estudar a sistemática e biogeografia dos curculionídeos de figo e, por isso, este estudo analisa o tempo de diversificação das linhagenes destes besouros para reconstruir sua biogeografia histórica. De modo a obter informações das espécies estudadas, foram coletadas 325 amostras de frutos de cerca de 12% do total de espécies de figueiras das regiões Neotropical, Afrotropical e Oriental. Sete coleções entomológicas (AMNH, BMNH, INBIO, MNHN, MZUSP, NMNH, SAMC) foram vistadas em busca de espécimes de curculionídeos coletados em figo. Pelo menos 80 espécies de cinco gêneros (Cetatopus, Omophorus, Carponinus, Curculio e Indocurculio) foram encontradas. A radiação dos curculionídeos de figo ocorreu independentemente pelo menos três vezes ao longo da história dos Curculionidae. O período de diversificação das linhagenes de curculionídeos de figo é fortemente congruente com o período de diversificação das linhagenes de figueiras durante o fim do Cretáceo/Paleoceno. Acredita-se que fatores como a forte variação no nível dos oceanos e o clima mais quente no passado tiveram grande influência na evolução das espécies. Espera-se que os resultados deste trabalho encorajem estudos futuros sobre a biologia e ecologia dos curculionídeos associados às figueiras e auxilie no entendimento do papel que os curculionídeos possam ter desempenhado na evolução do sistema Ficus - vespas de figo.
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Invertebrate community reassembly and altered ecosystem process rates following experimental habitat restoration in a mined peat bog in New Zealand

Watts, Corinne Hannah January 2006 (has links)
I investigated the effects ofhabitat loss and subsequent restoration on invertebrate community structure and ecosystem functioning in a mined peat bog in the North Island, New Zealand. In an experimental trial, the impact of peat bog habitat loss and isolation on the invertebrate community associated with Sporadanthus ferrugineus (Restionaceae) was investigated. Potted S. ferrugineus plants were exposed to invertebrates at various distances up to 800 m from an intact habitat (the presumed source population) over 18 weeks. Invertebrates rapidly colonised the experimental plants, with all major Orders and trophic groups present on Sc ferrugineus within 6 weeks. However. with increasing distance away from the undisturbed habitat, there was a significant decrease in total richness and abundance of invertebrates associated with the potted plants. Additional tests showed that even a moderate degree of isolation (i.e. greater than 400 m) from the intact habitat caused an almost complete failure of 'Batrachedra' sp. to colonise its host plant, at least in the short-term, The density of eggs and larvae, and the average larval size of 'Batrachedra' sp. (Lepidoptera: Coleophoridae) colonising Si ferrugineus plants, as well as the proportion of Si ferrugineus stems damaged by 'Batrachedra' sp. herbivory, all decreased logarithmically with increasing distance from the intact habitat. Surprisingly, though, the rate of recovery of the insect-plant interaction following experimental habitat restoration was remarkably rapid (i.e. between 3Y2 and 6 years). After just 6 years there was no significant difference in insect-plant interactions between the intact peat bog sites and any of the experimentally restored sites up to 800 m away. These results suggest that the degree of isolation from undisturbed habitat has a major impact on the rate and patterns of restoration recovery in the invertebrate community and that some insect-plant interactions can recover rapidly from habitat loss with restoration management. Restoration of mined peat bogs in northern New Zealand is initiated by establishing a native vegetation cover to minimize further peat degradation. The effects of various restoration techniques on litter decomposition, microbial community activity and beetle community composition were investigated within an experimental trial, These treatments included translocation ofpeat bog habitat (direct transfer of islands), milled peat islands with no seed and milled peat islands with seed, and were compared with an unrestored mined site and an undisturbed peat bog. In all the response variables measured, the undisturbed peat bog sites had significantly higher decomposition rates and microbial respiration rates, and significantly higher abundance and species richness of beetles than any of the restoration treatments. Inaddition, the technique used to restore mined peatlands had a significant effect on the beetle community composition and litter decomposition processes. Despite a rapid initial change in the beetle community following habitat translocation, the direct transfer islands were still the most similar in beetle species composition to the undisturbed peat bog. Microbial activity and decomposition rates were higher in the direct transfer and mined peat surface after 6 months. However, even after 12 months, decomposition rates in the restored habitats were still far from reaching the levels recorded in the undisturbed peat bog. The results suggest that beetle community structure and ecosystem processes such as decomposition and microbial activity rates may be able to recover faster with certain restoration techniques, such as direct transfer of intact habitat islands. Subsequently, I examined long-term beetle community reassembly on islands that had been restored by creating raised areas ofprocessed peat with the addition of Leptospermum scoparium seed. Monitoring of different-aged restored islands representing the full range of restoration ages (up to 6 years) available at the peat mine, indicated that as the peat islands became older and the vegetation structure became more complex, the abundance, species richness and composition of the beetle community became increasingly similar to the community in the undisturbed peat bog. Despite this, distinct differences between the intact peat bog and older restored peat islands still persisted, even after 6 years, particularly at an individual species level. However, it is predicted that within 12 years the restored peat islands will share 100% ofbeetle species in common with the undisturbed peat bog. Taken together, these results indicate that restoration is effective in initiating the recovery of beetle assemblages and ecosystem processes (such as litter decomposition and microbial community activity) in cut-over peat bogs. However, it is estimated to take at least 12 years before pre-mining communities and functions are attained, and ongoing monitoring to develop an understanding of the longer-term dynamics of such ecosystems and processes is clearly required.
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Evolutionary and mechanistic aspects of insect host plant preference

Schäpers, Alexander January 2016 (has links)
Plant feeding insects comprise about 25% of all animal species on earth and play an important role in all ecosystems. Although we understand that their association with plants is a key-factor driving the diversification in this group, we still have large gaps in our knowledge of the underlying processes of this relationship. Female choice of host plant is an important event in the insect life-cycle, as it is a major determinant of the larval food plant. In this Thesis I studied different aspects of insect host plant choice and used butterflies from the family Nymphalidae as my study system. I found that butterflies have a well developed olfactory system and that they use odors when searching for food or host plants. However, the information obtained from the odor of host plants does not seem to be sufficient for the studied species to make a distinction between plants of different qualities. Interestingly, even when in full contact with the leaf they do not make optimal decisions. I show for example that a sub-optimal female choice may be mitigated by larval ability to cope with unfavorable situations. Moreover, species that utilize a broader set of host plants may not be very well adapted to all the hosts they use, but at the same time they may survive in areas where there is only a subset of the plants available. Lastly, differences in the evolution of life-history traits between species can account for differences in how each species realizes its lifestyle. Thus, by incorporating findings on mechanisms of host plant choice with the ecological and evolutionary context of a species, our ability to explain the dynamics of host plant choice and insect-plant interactions can be improved. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

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