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Orientador: Maria Célia Portela / Resumo: Objetivou-se compreender a colonização do mexilhão-dourado, Limnoperna fortunei, por meio da relação entre densidade larval e incrustação das colônias. Também foram avaliadas as variáveis limnológicas e a densidade de Copepoda e Cladocera. A pesquisa foi realizada em piscicultura em tanques-rede no reservatório Chavantes, rio Paranapanema, município de Ipaussu, São Paulo. Entre janeiro e setembro de 2018 foi investigada a densidade de larvas de Limnoperna fortunei, Cladocera e Copepoda em três pontos e três profundidades (1,0; 2,5 e 5,0m) e o recrutamento do L. fortunei, mensal e acumulado, na superfície (15 x 15 cm) de tambores da piscicultura. Contagem e identificação das larvas de L. fortunei seguiram Cataldo et al. (2005) e de microcrustáceos o protocolo Zooplâncton de água doce: métodos qualitativo e quantitativo (CETESB, 2012). Os mexilhões aderidos aos substratos foram medidos com paquímetro digital e microscópio estereoscópico. O crescimento do molusco foi estimado utilizando a equação de Bertalanffy. Copepoda foram dominantes. Maior densidade de L. fortunei ocorreu de janeiro a março (máximo de 37.300 ind.m-3) com picos menores em maio e setembro e drástica redução de junho a agosto (menor que 5.000 ind.m-3). Maiores densidades de Copepoda e Cladocera também ocorreram de janeiro a março. No verão houve maior recrutamento do L. fortunei, com evidente redução no período mais frio. Portanto, o período reprodutivo influenciou diretamente na incrustação. Estimou-se que o ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective was to understand the colonization of the golden mussel, Limnoperna fortunei, by means of the relation between larval density and incrustation of the colonies. The limnological variables and the density of Copepoda and Cladocera were also evaluated. The research was carried out in fish culture in fish cage in the Chavantes reservoir, Paranapanema River, municipality of Ipaussu, São Paulo. Between January and September 2018, the density of larvae of Limnoperna fortunei, Cladocera and Copepoda was investigated in three points and three depths (1,0, 2,5 and 5,0m) and the recruitment of L. fortunei, monthly and accumulated , on the surface (15 x 15cm) of fish farming drums. Count and identification of larvae of L. fortunei followed Cataldo et al. (2005) and microcrustaceans the Freshwater Zooplankton protocol: qualitative and quantitative methods (CETESB, 2012). The mussels adhered to the substrates were measured with digital caliper and stereoscopic microscope. Mollusk growth was estimated using the Bertalanffy equation. Copepoda were dominant. Higher density of L. fortunei occurred from January to March (maximum of 37,300 ind.m-3) with lower peaks in May and September and a drastic reduction from June to August (less than 5,000 ind.m-3). Higher densities of Copepoda and Cladocera also occurred from January to March. In the summer there was more recruitment of L. fortunei, with evident reduction in the colder period. Therefore, the reproductive period had a direct ... (Complete abstract click electronic access below) / Mestre

Un grand nombre de paramètres environnementaux affectent les insectes, et l’identification des éléments impliqués dans l’adaptation aux stress est cruciale. La nutrition est une clé de cette adaptation : elle contrôle la santé des organismes, et par conséquent affecte leur tolérance au stress. Le microbiote intestinal module lui aussi les processus physiologiques des organismes, notamment en agissant sur le phénotype nutritionnel de l’hôte. Cependant, nous ignorons encore la capacité de ce microbiote à modifier la tolérance au stress de l’hôte. A travers la manipulation du microbiote et de la nutrition, nous avons testé les effets de l’interaction microbiote-nutrition chez Drosophila melanogaster en nous concentrant sur la tolérance au stress. Nous avons montré une nette dépendance des mouches à l’accès aux levures pour maintenir un développement et un métabolisme normal.A l’inverse, l’altération du développement générée par les substrats nutritionnellement pauvres ou par la surpopulation larvaire était bénéfique pour la tolérance au stress. Nous avons démontré que le microbiote peut partiellement compenser les effets d’une privation en levures, mais n’a pas d’effet quand elles sont en excès. Pour la thermotolérance, nous avons constaté que les effets du microbiote étaient très variables, et avons attribué cette variabilité à la présence ou l’absence des levures. Les assemblages de microorganismes environnementaux étaient modifiées par la composition du substrat, mais le microbiote intestinal était étonnamment stable. Ces résultats témoignent de l’importance des facteurs nutritionnels et du microbiote à moduler le développement et le phénotype des Drosophiles. / A large number of environmental parameters constrain insect species, and identifying the elements involved in the adaptation to stressful conditions is crucial. Nutrition is a key factor of this adaptation: it largely controls health of organisms and therefore their stress tolerance. In addition, it is now established that microbiota (i.e. the whole microbial community associated with a host) is much involved in physiological processes of organisms. In particular, gut microbiota is able to modulate host’s nutritional phenotype, resulting in complex dietary-dependent effects. Whether or not gut microbiota can act on stress tolerance is not clear. Thus, using experimental manipulation of microbiota and nutrition, we investigated the outcome of the microbiota-nutrition relationship on Drosophila melanogaster, with a special focus on stress tolerance. We showed a clear dependency of flies on yeasts availability to maintain a normal development, metabolism, and size. Conversely, impaired development resulting from artificial poor diets or from larval crowding was often beneficial for stress tolerance. We demonstrated that microbiota could partially compensate for the absence of yeast resource, but no effects were found in rich food contexts. We observed variable importance of microbiota on thermal tolerance, and attributed this variation to the presence or absence of yeasts. Environmental microorganisms communities were modified by diet composition but gut microbiota was surprisingly stable. Together, these findings highlight the importance of nutritional factors and microbiota in developmental and phenotypical plasticity of fruit flies.

Wolbachia is a maternally inherited, endosymbiotic bacterium that infects at least 40% of terrestrial arthropods. As a facultative symbiont in the majority of its hosts, Wolbachia commonly act as a reproductive parasite; however, there are a number of Wolbachia strains that do not cause reproductive manipulations in their hosts and have no apparent fitness enhancement, yet are stably maintained in populations at low to intermediate frequencies. How these strains of Wolbachia persist in nature has been a long-standing question and is still unresolved. One explanation for the persistence of such strains is that they provide a context-dependent fitness advantage to their hosts. In this thesis, I investigate one such strain of Wolbachia, wSuz, which infects the agricultural pest, Drosophila suzukii, also known as spotted wing Drosophila. To explore the possibility that wSuz may be involved in pathogen protection, I screened wild flies for Wolbachia and two naturally occurring RNA viruses, Teise Virus and a recently discovered virus related to Motts Mill Virus. I did not find an association between Wolbachia and virus infection. Additionally, I designed an experiment to test whether Wolbachia increases host fitness at high larval densities. Intriguingly, although there was no effect of density, the frequency of Wolbachia infection changed dramatically in just one generation, but in opposite directions in replicate experiments that were performed a month apart. These results support the hypothesis that Wolbachia frequencies can change quickly across generations and provide some type of condition-dependent benefit. The maintenance of Wolbachia remains a mystery, but my study provides some exciting clues about what conditions may be playing a role. / Graduate / 2022-05-10

A spiny (Palinuridae), slipper (Scyllaridae) and coral (Synaxidae) lobster larval composition and distribution study on the western edge of the Florida Current is presented. From the samples collected during 2007, phyllosoma larvae of Justitia longimanus, Panulirus argus, Parribacus spp., S. americanus, S. depressus and P. gundlachi were positively identified. Relative density catches of the phyllosoma larvae indicate that P. argus (Florida spiny lobster) is the most abundant species in the Straits of Florida. Data gathered during the study shows that P. argus larvae at different developmental stages occur throughout the year which supports the theory of multiple spawning and/or multiple sources. Larvae of genus Panulirus are difficult to distinguish from plankton samples and hence were identified as of P. argus since it is the most common species in the area. Family Palinuridae and Scyllaridae larval density spikes in July and May, coincide with their spawning peak periods of late March – early May and late January to late March respectively. Members of family Palinuridae showed higher densities at night, whereas those of family Scyllaridae showed higher densities during day catches. Larvae of all species showed close association between total length and developmental stage at earlier age. Variability in size and morphology within stage increases with older stages due to multiple molts and/or smaller sample size.

Made available in DSpace on 2016-01-26T12:51:51Z (GMT). No. of bitstreams: 1 angelitabarbosa_dissert.pdf: 1284734 bytes, checksum: 9ee3bba6bd44f03d69e3b378a64a84fa (MD5) Previous issue date: 2006-03-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Oviposition traps are considered important entomological surveillance tools for Aedes aegypti, although they are still not used in routine activities of the Dengue Control Program in Brazil. The aims of this study were to evaluate the behavior of oviposition traps and related them to larval density measures and climatic data. This study was performed in a quarter from São José do Rio Preto, state of São Paulo, where fifty blocks were selected and two houses in opposite sides of each block were chosen to have the traps installed. A trap was installed at unshaded outdoor sites in each house, next to plants and in a height ranging from 0,5m to 1m. A measure was made each fifteen days, from October 2003 to September 2004, with the installation of the oviposition traps in the first week and the removal of them at the second week. Larval density measures were performed each fifteen days and climatic data was obtained on daily basis. The method of Generalized Estimation Equation was used to adjust the models among the positivity, the mean number of eggs and the other analyzed variables. Three distinct periods were identified at the positivity behavior of the oviposition traps and the mean number of obtained eggs. At the first (October to November), there was an increase in the values; at the second (January to May), the values remained stable; and at the third (June to September), there was a decrease. The observed values of positivity and the mean number of eggs observed at the first and third periods followed the variations in climatic data. From October to December, high correlations were obtained between the positivity and mean number of eggs, showing that one variable predicts the other and, at this period, the mean number of eggs can be estimated just by the positivity. The adjusted models for the positivity and mean number of eggs had temperature, humidity, pluviosity and fortnight as explicative variables. They also indicated the possibility of obtaining predictive models in a way these measures could be estimated without the necessity of fieldwork activities. For both models, the larval density measure was not included as an explicative variable. The trap presented a sensibility to detect Aedes aegypti higher than 90% and the larval density measures were always inferior to 25%. The periods from October to December and June to September were identified as the most appropriate to use oviposition traps as entomological surveillance tools. The period from December to June was identified as the ideal time to perform larval density measures. / Armadilhas de oviposição são consideradas importantes medidas de vigilância entomológica para Aedes aegypti, entretanto ainda não são utilizadas nas atividades de rotina no Programa de Controle da Dengue no Brasil. Este estudo teve como objetivos avaliar o comportamento das armadilhas de oviposição e relacioná-lo com as medidas de densidade larvária e climáticas. O trabalho foi realizado em um bairro da cidade de São José do Rio Preto, Estado de São Paulo, onde 50 quadras foram selecionadas e, em cada quadra, foram escolhidas duas casas em faces opostas. Em cada casa foi instalada uma armadilha no peridomicílio ao relento, próxima às plantas e a uma altura de 0,5m a 1m. Foram feitas medidas quinzenais, entre outubro/2003 a setembro/2004, com a colocação das armadilhas na primeira semana e retirada na segunda. Foram realizadas, quinzenalmente, medidas de densidade larvária e obtidos dados climáticos diários. Utilizou-se o método das Equações de Estimação Generalizadas para ajuste de modelos entre a positividade e o número médio de ovos e as demais variáveis analisadas. Foram identificados três períodos distintos no comportamento da positividade das armadilhas e no número médio de ovos encontrados. No primeiro (outubro a dezembro) ocorreu aumento dos valores, no segundo (janeiro a maio) os valores permaneceram em um patamar e no terceiro (junho a setembro) ocorreu decréscimo. Os valores da positividade e o número médio de ovos observados no primeiro e terceiro períodos acompanharam as variações observadas nos dados climáticos. Durante os meses de outubro a dezembro, altas correlações foram obtidas entre a positividade e número médio de ovos, mostrando que uma variável prediz a outra e que neste período o número médio de ovos pode ser estimado apenas pela positividade. Os modelos ajustados para a positividade e o número médio de ovos tiveram como variáveis explicativas temperaturas, umidades, pluviosidade e quinzena e indicaram a possibilidade da obtenção de modelos preditivos de modo que essas medidas poderiam ser estimadas sem a necessidade da realização de atividades de campo. Para ambos os modelos, a medida de densidade larvária não foi incluída como variável explicativa. A armadilha apresentou sensibilidade para a detecção de Aedes aegypti sempre superior a 90% e a medida de densidade larvária sempre inferior a 25%. Identificaram-se os períodos de outubro a dezembro e junho a setembro com os mais propícios para utilização das armadilhas de oviposição como medidas de vigilância entomológica e o período de dezembro a junho como ideal para a realização de medidas de densidade larvária.