• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 51
  • 9
  • 4
  • 2
  • 2
  • Tagged with
  • 68
  • 68
  • 45
  • 36
  • 31
  • 27
  • 17
  • 15
  • 11
  • 11
  • 11
  • 9
  • 8
  • 8
  • 7
  • 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

Associações entre aranhas Salticidae e Bromeliaceae : historia natural, distribuição espacial e mutualismos / Associations between jumping spiders (Salticidae) and Bromeliaceae

Romero, Gustavo Quevedo, 1974- 07 June 2005 (has links)
Orientador: João Vasconcellos Neto / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-04T21:51:53Z (GMT). No. of bitstreams: 1 Romero_GustavoQuevedo_D.pdf: 5256133 bytes, checksum: 5c71ea8abd971f76045303bc89c57a3b (MD5) Previous issue date: 2005 / Resumo: O entendimento das interações entre artrópodes e plantas tem crescido consideravelmente nos últimos poucos anos. Embora as aranhas estejam entre os grupos de artrópodes mais abundantes e constituam as principais guildas de predadores sobre a vegetação, poucos estudos envolvendo aranhas e plantas foram desenvolvidos. Aqui, reportamos um conjunto de informações mostrando que algumas espécies de salticídeos são estritamente associadas com Bromeliaceae em várias fitofisionomias sul-americanas, incluindo cerrados, florestas semidecíduas e sazonais, vegetação de dunas costeiras, restingas, afloramentos rochosos, florestas de altitude, chacos e florestas ombrófilas densas, em várias localidades do Brasil, Paraguai, Bolívia e Argentina. Enquanto algumas espécies de aranhas foram especialistas, ocorrendo quase exclusivamente em uma única espécie de planta hospedeira (e.g., Psecas chapoda sobre Bromelia balansae), outras foram generalistas e habitaram até 7-8 espécies de bromélias. Geralmente, as aranhas habitaram e selecionaram as bromélias maiores e/ou aquelas com arquitetura natural (e.g., simulação de inflorescência ou inclusão de folhas secas no centro da roseta). Portanto, as aranhas podem avaliar, em detalhes finos, o estado físico dos seus microhabitats. Bromélias podem muitas vezes fornecer microhabitats apropriados específicos para salticídeos. Suas folhas formam uma arquitetura tridimensional complexa (roseta), que pode ser usada por adultos e imaturos como abrigo contra predadores ou condições climáticas severas, como sítios de forrageamento, acasalamento e de oviposição, e como berçários para as recém emergidas das ootecas. Em troca, as aranhas contribuíram para a nutrição das bromélias. Usando métodos isotópicos (15N), nós verificamos que P. chapoda contribuiu com até 40% do N total de B. balansae no campo. Entretanto, os efeitos benéficos das aranhas foram enfraquecidos onde estas ocorreram em baixa abundância, e a condicionalidade foi gerada pela variação especial na densidade de aranhas / Abstract: The understanding of the interactions between arthropods and plants has grown considerably in the last few years. Although the spiders are among the most abundant arthropod group and compose the main predator guild on vegetation, there exist very few studies involving spiders and plants. Here, we report information showing that some salticid species are strictly associated with the Bromeliaceae in several South American phytophysiognomies, including cerrados (savanna-like vegetation), semideciduous and seasonal forests, coastal sand dune vegetation, restingas, inselbergs, highland forests, chacos and rain forests in several localities of Brazil, Paraguay, Bolivia and Argentina. While some species are specialists, occurring almost exclusively on a single host plant species (e.g., Psecas chapoda on Bromelia balansae), others are generalists and inhabit up to 7-8 bromeliad species. Generally, the spiders inhabited the larger bromeliads and/or those with natural architecture (e.g., simulation of inflorescence or inclusion of dry leaves in the center of the rosette). Therefore, the spiders seem to evaluate, in fine detail, the physical state of their microhabitats. Bromeliads may often provide specifically suitable microhabitats for jumping spiders. Their leaves form a complex tri-dimensional architecture (rosette), which can be used by adults and immature as shelter against predators or harsh climatic conditions, as foraging, mating and laying egg sites, and as nursery for spiderlings. In exchange, the spiders contributed to bromeliad nutrition. By using stable isotope methods (15N), we found that P. chapoda contributed with up to 40% of the total nitrogen of B. balansae in the field. However, the beneficial effects of the spiders were weakened where they occurred in low abundance, and conditionality was generated by spatial variation in spider density / Doutorado / Ecologia / Doutor em Ecologia
12

História natural e performance larval de Oospila pallidaria (Schaus, 1897) (Lepidoptera, Geometridae, Geometrinae): uma mariposa esmeralda do Cerrado / Natural history and larval performance of the Oospila pallidaria (Schaus, 1897) (Lepidoptera, Geometridae, Geometrinae): a emerald moth of Cerrado.

Bruno de Sousa Lopes 23 May 2016 (has links)
São estimadas 90 mil espécies de insetos para o Cerrado, o segundo maior bioma brasileiro, com enorme heterogeneidade de habitats e rica fauna. Dentre esses insetos, os Lepidoptera representam cerca de 10% do total de espécies. Entretanto, estudos sobre seus imaturos (ovo, larva e pupa) ainda são incipientes para o bioma, principalmente sobre as mariposas, cujas histórias naturais de muitas espécies ainda são desconhecidas. A falta desses estudos faz com que sejam ignoradas as interações multitróficas em que esses organismos estão envolvidos e, portanto, inviabiliza futuros estudos relacionados ao seu papel em comunidades e redes ecológicas. Esse é o caso de muitas espécies da família Geometridae, incluindo Oospila pallidaria, que é uma mariposa esmeralda (devido à coloração verde esmeralda das suas asas). Oospila pallidaria é uma espécie herbívora que não possuía até o momento nenhuma informação publicada sobre a sua biologia e fatores que condicionam sua ocorrência, tais como: a fenologia da planta hospedeira, que pode determinar o período de melhores condições para crescimento e reprodução; a qualidade nutricional dos recursos alimentares (e. g. quantidade de água e nitrogênio), que pode determinar quais recursos conferem melhor desenvolvimento/performance a um herbívoro; os inimigos naturais, que podem restringir a ocorrência dos herbívoros e a temperatura e pluviosidade, que podem alterar a qualidade e a distribuição geográfica dos recursos alimentares utilizados pelos herbívoros. Nesse sentido, o objetivo principal deste estudo foi descrever, pela primeira vez, aspectos da biologia e história natural de O. pallidaria (Capítulo 1) e avaliar a sua performance larval, a partir de diferentes dietas (Capítulo 2). Os resultados apresentados no Capítulo 1 mostraram que os ovos de O. pallidaria, verdes e com duração média de sete dias, foram solitários e ovipostos principalmente nos tricomas das folhas maduras. As larvas se alimentaram de folhas maduras predominantemente, mas utilizaram folhas jovens e botões florais oportunisticamente. As larvas tiveram coloração críptica, se camuflaram em meio às folhas de Mimosa setosa (Leguminosae: Mimosoideae), sua única hospedeira, e desenvolveram o comportamento de auto-limpeza. Há cinco ínstares larvais, com coloração que variou de amarelo a verde. As larvas apresentaram também um par de projeções no protórax e linha mediana marrom na região dorsal. O comprimento máximo do corpo das larvas foi de 28 mm. As pupas foram predominantemente verdes, com no máximo 10 mm de comprimento. O desenvolvimento do ovo ao adulto durou cerca de 50 dias ( = 42; S = 6; n = 11). Seu único inimigo natural registrado foi o microhimenóptero Cotesia sp. (Braconidae, Microgastrinae). Fêmeas de O. pallidaria produziram 65 ovos em média (S = 7,07; n = 2). A ocorrência de O. pallidaria foi sazonal e sobreposta ao pico de presença de folhas maduras. Larvas foram negativamente relacionadas à temperatura e pluviosidade, com significância estatística somente para a primeira (r = - 0.5889, P < 0.05). No Capítulo 2, foi mostrado que as folhas maduras de M. setosa foram o único recurso alimentar disponível durante todo o ano. Os botões florais foram o recurso com maior qualidade nutricional (conteúdo relativo de água e nitrogênio total), seguidos por folhas jovens e maduras respectivamente. Entretanto, a sobrevivência de O. pallidaria foi maior com folhas maduras. Os resultados indicam que para o herbívoro especialista O. pallidaria, a fenologia da planta hospedeira é crucial para sua sobrevivência, em especial a presença de folhas maduras de M. setosa. Por outro lado, os botões florais são recursos efêmeros, porém importantes para a sobrevivência das larvas de últimos ínstares no final da estação seca, quando as folhas maduras estão ressecadas e/ou senescentes. / It is estimated 90.000 species of insects for the Cerrado, the second largest Brazilian biome, with great diversity of habitats and rich fauna. Among these insects, Lepidoptera represents about 10% of all species. However, studies on their immature stages (egg, larvae and pupae) are incipient for the biome, mostly on moths, whose natural histories of many species are unknown. The lack of these studies makes the multitrophic interactions in that these organisms are involved ignored and, therefore, prevent future studies related to their role in communities and ecological networks. This is the case of many species of Geometridae, including Oospila pallidaria, which is an emerald moth (due to emerald green color of their wings). Oospila pallidaria is a herbivorous species that had not published any information on their biology and factors that influence their occurrence, such as: the phenology of the host plant, which can determine the time of better conditions for growth and reproduction; the nutritional quality of food resources (e. g. amount of water and nitrogen), which can determine what resources provide better development/performance to a herbivore; natural enemies, that could restrict the occurrence of herbivores and the temperature and rainfall, which can change the quality and geographical distribution of food resources used by herbivores. Accordingly, the aim of this study was to describe, for the first time, aspects of the biology and natural history of O. pallidaria (Chapter 1) and to assess their larval performance from different diets (Chapter 2). The results presented in Chapter 1 showed that eggs of O. pallidaria, green and lasting an average of seven days, were lonely and laid especially in trichomes of mature leaves. The larvae fed on mature leaves predominantly, but used young leaves and flower buds opportunistically. Larvae had cryptic coloration, they camouflaged among the leaves of Mimosa setosa (Leguminosae: Mimosoideae), a single host, and developed the self-cleaning behavior. There are five larval instars, with color ranging from yellow to green. The larvae also had a pair of projections on prothorax and brown midline in the dorsal region. The maximum length of the larvaes body was 28 mm. The pupae were predominantly green, with a maximum of 10 mm in length. The development from egg to adult lasted about 50 days ( = 42, S = 6, n = 11). Their only natural enemy recorded was the microhymenopteran Cotesia sp. (Braconidae, Microgastrinae). Oospila pallidaria females produced 65 eggs on average (S = 7.07; n = 2). The occurrence of O. pallidaria was seasonal and overlapped on the peak presence of mature leaves. Larvae were negatively related to temperature and rainfall, with statistical significance only for the first (r = - 0.5889, P < 0.05). In Chapter 2, it was shown that mature leaves of M. setosa were the only food source available throughout the year. The flower buds were the resource with higher nutritional quality (relative water content and total nitrogen), followed by young and mature leaves respectively. However, the survival of O. pallidaria was greater with mature leaves. The results indicate that for the specialist herbivore O. pallidaria, the host plant phenology is critical for its survival, especially the presence of mature leaves of M. setosa. On the other hand, the flower buds are ephemeral resources, but important for the survival of the last instar larvae in the dry season, when mature leaves are withered and/or senescent.
13

COMUNIDADE DE INSETOS ASSOCIADOS AOS SICÔNIOS DE TRÊS ESPÉCIES DE FIGUEIRAS NO PANTANAL SUL MATOGROSSENSE / INSECT COMMUNITY ASSOCIATED WITH SYCONIA OF THREE FIG SPECIES IN PANTANAL SUL MATOGROSSENSE

Costa, Priscila Canesqui da 29 July 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Syconia of fig trees present a diverse interaction with different groups of organisms. In this study we characterized insect community associated with three fig species in the region of Miranda/Abobral, Pantanal Sul matogrossense, obtaining data about species richness and abundance of these insects. We verified the specificity of these insects in regard to hosts and tested whether the size and number of flowers in the syconium determine species richness and abundance of insects in the syconia. We found 31 morpho-species of insects in the syconia of the three hosts. Syconia of Ficus obtusifolia had the highest richness (N = 18) and highest number of species co-occurring in the same syconia. Seven insect species were found sharing hosts. Mean abundance and species richness of insects in syconia of F. obtusifolia were significantly higher than in F. pertusa and F. luschnathiana what was related to the higher volume and number of flowers in the syconia of this fig tree. Our data may help in understanding the diversity and distribution of the insects associated with syconia of fig trees in the neotropical region. Papers that study Ficus insects associated system are important to show how these interactions occur in distinct fig trees and in different localities. / Sicônios de figueiras apresentam uma diversificada interação com diferentes grupos de organismos. Neste estudo, nós caracterizamos a comunidade de insetos associados a três espécies de figueiras na região do Miranda/Abobral, Pantanal Sul matogrossense, obtendo dados sobre a riqueza de espécies e a abundância destes insetos. Verificamos a especificidade destes insetos em relação aos hospedeiros e testamos se o volume e o número de flores dentro do sicônio determinam a riqueza de espécies e a abundância de insetos dentro dos sicônios. Foram encontradas 31 morfo-espécies de insetos nos sicônios das três espécies de figueiras analisadas. Sicônios de F. obtusifolia apresentaram a maior riqueza de espécies (S = 18) e maior número de espécies coocorrendo no mesmo sicônio. Sete espécies de insetos compartilharam hospedeiros. A média da abundância e da riqueza de espécies de insetos co-ocorrendo em sicônios de F. obtusifolia foi significativamente maior do que em F. pertusa e F. luschnathiana, fato que está ligado ao maior volume e número de flores nos sicônios desta figueira. Nossos resultados podem auxiliar no entendimento da diversidade e distribuição de insetos associados a sicônios de figueiras na região Neotropical. Trabalhos que abordam o sistema Ficus insetos associados são importantes para responder como estas interações acontecem em espécies de figueiras distintas e em diferentes localidades.
14

Randomized clinical trials evaluating therapeutic influences of ornamental indoor plants in hospital rooms on health outcomes of patients recovering from surgery

Park, Seong-Hyun January 1900 (has links)
Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Richard H. Mattson / Medical and psychological responses of patients recovering from surgery were evaluated in hospital rooms with ornamental indoor plants. Three clinical studies were conducted in two hospitals with 80 thyroidectomy patients, 90 appendectomy patients, and 90 hemorrhoidectomy patients. Patients in each surgical procedure were randomly assigned to either control or plant rooms. Eight species of foliage and flowering plants were placed in the hospital rooms during the recovery period following surgery until discharge. Data collected from each patient included length of hospitalization, analgesics used for postoperative pain control, vital signs (blood pressure, temperature, heart rate, and respiratory rate), ratings of pain intensity, pain distress, anxiety and fatigue (PPAF), the State-Trait Anxiety Inventory Form Y-1 (STAI-Y1), the Environmental Assessment Scale (EAS), and the Patient’s Room Satisfaction Questionnaire (PRSQ). Effects were assessed by analysis of covariance and the exact chi-square test. Patients in the plant rooms had significantly more positive health outcomes than those in the control group with no plants. Patients exposed to plants experienced shorter hospitalizations, fewer intakes of postoperative analgesics, more positive physiological responses, and less pain, anxiety, and fatigue than patients in the control group. Patients with plants also felt more positively about their rooms and evaluated them with higher satisfaction as compared to those in the control group. Based on patients’ comments, plants brightened up the room environment, reduced stress, and also conveyed positive messages of the hospital caring for patients. Findings of this study confirmed the therapeutic value of plants in the hospital environment as a noninvasive, inexpensive, and effective intervention for surgical patients in a general hospital ward. Outcomes of this study will substantially affect patients’ and hospital administrators’ decisions that indoor plant intervention can foster improved medical outcomes, increase satisfaction with providers, and be acceptably cost effective as compared to other alternatives.
15

Visitantes florais e efici?ncia de poliniza??o em Jacquemontia bracteosa Meisn (Convolvulaceae) em uma ?rea no Semi?rido brasileiro

Santos, Silvia Karla Dias dos 18 April 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-02-29T22:35:01Z No. of bitstreams: 1 Disserta?ao Silvia.pdf: 886694 bytes, checksum: 049402a0d6acf81a0e49439f59de35f9 (MD5) / Made available in DSpace on 2016-02-29T22:35:01Z (GMT). No. of bitstreams: 1 Disserta?ao Silvia.pdf: 886694 bytes, checksum: 049402a0d6acf81a0e49439f59de35f9 (MD5) Previous issue date: 2013-04-18 / Convolvulaceae flowers are characterized mainly by being beautiful and ephemeral, attracting many visitor flowers that belong to different taxonomic groups. They are often found in open environments acting as an important food resource to flower visitors especially bees. This work aimed to investigate the interactions between insects and flowers of Jacquemontia bracteosa Meisn visitors (Convolvulaceae) identifying the pollinator potentials in a semi-arid area in the Northeast. The study was carried out from November 2011 to October 2012, when the morphology and floral biology and reproductive biology of J. bracteosa and floral visitors. The J. bracteosa flowers opened early morning and lasted less than 12 hours, being considered ephemeral. These were self-compatible breeding system, with fruiting by selfing and outcrossing. The flowers were visited mainly by Apidae family bees (females and males of Ancyloscelis apiformis, Ceratina aff maculifrons and Trigona spinipes) and family Halictidae (Augochlora spp). Other visitors were collected from flowers with its frequency below 1%. Among the floral visitors A. apiformis was considered the most efficient pollinator for showing behavior, frequency, and constancy on the flowers. Furthermore, these bees arrived soon when the flowers began to open and presented 90% of efficiency in tests with three visited flowers of J. bracteosa. Other bees as T. spinipes, Ceratina aff maculifrons, Exomalopsis analis, Exomalopsis sp1, and Pseudaugochlora sp1 may be considered potential pollinators because they present behavior and morphology compatible with the flowers. / Flores de Convolvulaceae s?o caracterizadas principalmente por serem ef?meras e vistosas, atraindo muitos visitantes florais pertencentes a grupos taxon?micos diferentes. S?o frequentemente encontradas em ambientes abertos atuando como importante fonte de recursos alimentares aos visitantes florais especialmente abelhas. O presente trabalho teve como objetivo estudar as intera??es entre os insetos visitantes e Jacquemontia bracteosa Meisn. (Convolvulaceae), identificando os potenciais polinizadores em uma ?rea no semi-?rido do Nordeste do Brasil. O estudo foi realizado de novembro de 2011 a outubro de 2012, e foram analisados aspectos da morfologia e biologia floral e biologia reprodutiva de J. bracteosa e dos visitantes florais. As flores de J. bracteosa abriam entre 5:10 e 6:20 e duravam menos de 12 horas, sendo consideradas ef?meras. Estas apresentavam sistema reprodutivo autocompat?vel, com frutifica??o por poliniza??o cruzada e autopoliniza??o. As flores foram visitadas principalmente por abelhas das fam?lias Apidae (f?meas e machos de Ancyloscelis apiformis, Ceratina aff maculifrons, Exomalopsis analis, Exomalopsis sp1 e Trigona spinipes) e Halictidae (Augochlora spp). Outros visitantes foram coletados nas flores apresentando frequ?ncia abaixo de 1%. Dentre os visitantes florais A. apiformis foi considerada o polinizador mais eficiente por apresentar comportamento compat?vel com a poliniza??o na esp?cie, frequ?ncia alta de visitas e const?ncia nas flores. Al?m disso, estas abelhas chegavam logo quando a flor come?ava a abrir e apresentaram 90% de efici?ncia nos testes realizados com tr?s visitas nas flores de J. bracteosa. Outras abelhas como T. spinipes, Ceratina aff maculifrons, Exomalopsis analis, Exomalopsis sp1 e Pseudaugochlora sp1 podem ser consideradas polinizadores potenciais, pois apresentam comportamento e morfologia compat?veis com a poliniza??o das flores.
16

Spring Phenology of Butterflies : The role of seasonal variation in life-cycle regulation

Stålhandske, Sandra January 2016 (has links)
Animals and plants in temperate regions must adapt their life cycle to pronounced seasonal variation. The research effort that has gone into studying these cyclical life history events, or phenological traits, has increased greatly in recent decades. As phenological traits are often correlated to temperature, they are relevant to study in terms of understanding the effect of short term environmental variation as well as long term climate change. Because of this, changes in phenology are the most obvious and among the most commonly reported responses to climate change. Moreover, phenological traits are important for fitness as they determine the biotic and abiotic environment an individual encounters. Fine-tuning of phenology allows for synchronisation at a local scale to mates, food resources and appropriate weather conditions. On a between-population scale, variation in phenology may reflect regional variation in climate. Such differences can not only give insights to life cycle adaptation, but also to how populations may respond to environmental change through time. This applies both on an ecological scale through phenotypic plasticity as well as an evolutionary scale through genetic adaptation. In this thesis I have used statistical and experimental methods to investigate both the larger geographical patterns as well as mechanisms of fine-tuning of phenology of several butterfly species. The main focus, however, is on the orange tip butterfly, Anthocharis cardamines, in Sweden and the United Kingdom. I show a contrasting effect of spring temperature and winter condition on spring phenology for three out of the five studied butterfly species. For A. cardamines there are population differences in traits responding to these environmental factors between and within Sweden and the UK that suggest adaptation to local environmental conditions. All populations show a strong negative plastic relationship between spring temperature and spring phenology, while the opposite is true for winter cold duration. Spring phenology is shifted earlier with increasing cold duration. The environmental variables show correlations, for example, during a warm year a short winter delays phenology while a warm spring speeds phenology up. Correlations between the environmental variables also occur through space, as the locations that have long winters also have cold springs. The combined effects of these two environmental variables cause a complex geographical pattern of phenology across the UK and Sweden. When predicting phenology with future climate change or interpreting larger geographical patterns one must therefore have a good enough understanding of how the phenology is controlled and take the relevant environmental factors in to account. In terms of the effect of phenological change, it should be discussed with regards to change in life cycle timing among interacting species. For example, the phenology of the host plants is important for A. cardamines fitness, and it is also the main determining factor for oviposition. In summary, this thesis shows that the broad geographical pattern of phenology of the butterflies is formed by counteracting environmental variables, but that there also are significant population differences that enable fine-tuning of phenology according to the seasonal progression and variation at the local scale. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>
17

Geochemical Characterization of Tea Leaves (Camellia sinensis) and Soils for Provenance Studies based on Compositional Data Analysis

Pospiech, Solveig 17 September 2018 (has links)
No description available.
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).

Rocha, Luciano Palmieri 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.
19

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

Santos, Franciele dos 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.
20

Variabilidade genética de isolados de Fusarium spp. e estudo da interação com a planta hospedeira. / Genetic variability of Fusarium spp. and study of its interaction with the host plant.

Martins, Mayra Kassawara 18 April 2005 (has links)
O Fusarium spp. é um fungo cosmopolita, compreendendo uma grande quantidade de espécies que são conhecidas por causar doenças em culturas de importância agronômica. Embora, isolados não patogênicos de Fusarium spp. tenham sido descritos, pouco se conhece sobre a variabilidade genética deste grupo, ainda que estejam presentes em inúmeros locais. Assim sendo, este trabalho teve como objetivos ampliar estes conhecimentos, avaliando a variabilidade genética e forma de interação de isolados patogênicos e não patogênicos de Fusarium spp. obtidos de diferentes hospedeiros. Desta forma, 83 isolados de Fusarium spp. foram avaliados por meio das técnicas de ARDRA, sequenciamento do rDNA e RAPD. A análise por meio de ARDRA, permitiu a distinção dos 83 isolados de Fusarium spp. em 19 haplótipos, apresentando uma grande diversidade dentro de cada haplótipo, mas de forma geral os isolados patogênicos e não patogênicos de Fusarium spp. não puderam ser discriminados. Nas análises de sequenciamento da região ITS do rDNA, foi observado que isolados de Fusarium se agruparam independentemente da espécie. Estes resultados comprovam a necessidade de uma revisão taxonômica dentro do gênero Fusarium. A análises por marcadores RAPD revelou que os 83 isolados de Fusarium spp. avaliados neste estudo apresentaram ampla variabilidade a qual não está correlacionada com a característica taxonômica. Entretanto, foi observado que isolados patogênicos e endofíticos de F. oxysporum obtidos de soja são geneticamente diferentes. Quanto às análises de interação de isolados patogênicos e não patogênicos de Fusarium spp. com cultivares susceptíveis de tomate e soja, verificou-se que estes isolados interagiram de forma diversa, nos diferentes tecidos vegetais, sendo que alguns isolados endofíticos promoveram o crescimento vegetal. Dentre estes, destaca-se o isolado endofítico Cac19.4 que mostrou-se geneticamente diferente de isolados patogênicos de Fusarium spp., além de promover um aumento de peso da raiz e caule de plântulas de soja e tomate. Dessa forma este isolado poderia ser selecionado para futuras análises, visando um melhor aproveitamento deste microrganismo endofítico em estudos de interesse agronômico. / Fusarium spp. is a cosmopolitan fungus that covers a great number of species known by the ability of causing diseases in agricultural important crops. Although non-pathogenic isolates of Fusarium spp. have been described, little is known about the genetic variability of this group, even if it can be found in countless places. Therefore, this work had the objectives of increase this knowledge, evaluating the genetic variability and modes of interaction between Fusarium spp pathogenic and non-pathogenic isolates, obtained from different hosts. In this way, ARDRA, rDNA sequencing, and RAPD techniques evaluated 83 Fusarium spp. isolates. The ARDRA analysis allowed the separation of 83 isolates in 19 haplotypes. In spite of the great diversity found inside each haplotypes, in general it was difficult to distinguish pathogenic and nonpathogenic isolates. In the sequencing analysis of the ITS region of rDNA, it was observed that Fusarium isolates were grouped together independently to the species. These results proved the need for a taxonomic review inside Fusarium genera. The RAPD analysis revealed that the 83 Fusarium spp. isolates evaluated in this study presents high levels of variability not correlated with the taxonomic characteristic. However, we observed that pathogenic and endophytical F. oxysporum isolated from soybean are genetically different. The interaction analysis between pathogenic and non-pathogenic isolates of Fusarium spp. with susceptible cultivars of tomato and soybean, showed different modes of interaction on different plant tissues, where some endophytical isolates increased plant growth. Among these, we can emphasize the endophytic isolate Cac19.4, that is genetically different if compared with Fusarium spp. pathogenic isolates, in spite of his ability to promote an increase in root and stems weight of soybean and tomato plantlets. Thus, this isolate could be selected for further analysis, looking for a better use of this endophytical microorganism in agricultural interest studies.

Page generated in 0.1754 seconds