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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.
201

Evolutionary ecology of Malpighiaceae pollination at the species and community levels

Cappellari, Simone Caroline 18 November 2013 (has links)
Plant-pollinator interactions figure as key elements promoting the natural regeneration of terrestrial vegetation, as most plants depend on animals to transfer their gametes between flowers and produce seeds. Bees are the most common pollinators of plants and their interactions with flowers have served as model systems for the study of specialized mutualisms since Darwin's time. While most plants offer nectar as a reward and attract a variety of floral visitors, others produce distinctive types of resources which are sought by particular groups of pollinators. Such associations may involve specialization at the morphological, behavioral, or physiological levels and are especially common in tropical habitats. The interactions between oil-producing flowers of Neotropical Malpighiaceae and oil-collecting bees are an example of a specialized mutualism in which plants offer lipids to attract pollinators that use the resource to build nest cells and feed their offspring. Although several studies have focused on specialized pollination at the species level, their effects on the organization of tropical communities remain largely unexplored. This dissertation aims to help fill this gap through an analysis of the mechanisms of pollinator partitioning in multi-species assemblages of specialists as well as a study of the organization of communities in which they occur. The motivation for pursuing the study of specialized interactions using Neotropical species of Malpighiaceae as a model system is outlined in the first chapter. In Chapter 2, I present an evaluation of the structural properties of a plant-pollinator community from the Cerrado, a seasonal ecosystem that hosts a large diversity of oil flowers. The third chapter analyzes pollinator partitioning and reproductive strategies promoting the coexistence of closely related Malpighiaceae. A possible outcome for the selective pressures imposed by the coexistence of specialists is presented in Chapter 4 by a case study providing evidence for a shift from specialized to generalized pollination in a Neotropical Malpighiaceae species. The last chapter includes reports of active floral oil foraging by males of Tetrapedia and a description of an oil storage structure without precedence among bees and unique to males of this genus suggesting that floral oils may also play a role in bees mating systems. / text
202

The impact of the European honey bee (Apis mellifera) on Australian native bees

Paini, Dean January 2004 (has links)
The European honey bee (Apis mellifera) has been present in Australia for approximately 150 years. For the majority of that time it was assumed this species could only be of benefit to Australia‘s natural ecosystems. More recently however, researchers and conservationists have questioned this assumption. Honey bees are an introduced species and may be affecting native fauna and flora. In particular, native bees have been highlighted as an animal that may be experiencing competition from honey bees as they are of similar sizes and both species require nectar and pollen for their progeny. Most research to date has focused on indirect measures of competition between honey bees and native bees (resource overlap, visitation rates and resource harvesting). The first chapter of this thesis reviews previous research explaining that many experiments lack significant replication and indirect measures of competition cannot evaluate the impact of honey bees on native bee fecundity or survival. Chapters two and four present descriptions of nesting biology of the two native bee species studied (Hylaeus alcyoneus and an undescribed Megachile sp.). Data collected focused on native bee fecundity and included nesting season, progeny mass, number of progeny per nest, sex ratio and parasitoids. This information provided a picture of the nesting biology of these two species and assisted in determining the design of an appropriate experiment. Chapters three and five present the results of two experiments investigating the impact of honey bees on these two species of native bees in the Northern Beekeepers Nature Reserve in Western Australia. Both experiments focused on the fecundity of these native bee species in response to honey bees and also had more replication than any other previous experiment in Australia of similar design. The first experiment (Chapter three), over two seasons, investigated the impact of commercial honey bees on Hylaeus alcyoneus, a native solitary bee. The experiment was monitored every 3-4 weeks (measurement interval). However, beekeepers did not agist hives on sites simultaneously so measurement intervals were initially treated separately using ANOVA. Results showed no impact of honey bees at any measurement interval and in some cases, poor power. Data from both seasons was combined in a Wilcoxon‘s sign test and showed that honey bees had a negative impact on the number of nests completed by H. alcyoneus. The second experiment (Chapter 5) investigated the impact of feral honey bees on an undescribed Megachile species. Hive honey bees were used to simulate feral levels of honey bees in a BACI (Before/After, Control/Impact) design experiment. There was no impact detected on any fecundity variables. The sensitivity of the experiment was calculated and in three fecundity variables (male and female progeny mass and the number of progeny per nest) the experiment was sensitive enough to detect 15-30% difference between control and impact sites. The final chapter (Chapter six) makes a number of research and management recommendations in light of the research findings.
203

Termogênese e distribuição de calor pela cria de abelhas sem ferrão e sua relação com o estágio de desenvolvimento em ambiente semiárido / Thermogenesis and distribution of heat by brood of stingless bees and its relation to the stage of development in semi-arid environment

Dantas, Maiko Roberto Tavares 20 June 2014 (has links)
Made available in DSpace on 2016-08-15T20:31:17Z (GMT). No. of bitstreams: 1 MaikoRTD_DISSERT.pdf: 3173306 bytes, checksum: 9cc3843dd152fa6df98a537e8bc1b488 (MD5) Previous issue date: 2014-06-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The study of thermoregulation in stingless bees (Hymenoptera, Apidae, Meliponini) is essential to better understand the adaptation of these insects to the environment to which they are inserted. Its physiological behavior regarding different temperatures helps to understand the evolution of their society. The mechanisms of thermal exchanges are important strategies to ensure the survival of a species, especially for the more immature individuals, ie the brood. This work was conducted at the Experimental Field Station "Rafael Fernandes", belonging to UFERSA in Mossoró-RN, Caatinga biome. 10 brood combs of Melipona subnitida were analyzed by thermography and measured the temperatures of the surfaces of cells separated into 10 categories, divided into seven different brood's stages of development, cells with dead individuals, empty cells and cells containing larvae and pupae of the parasite Plega hagenella. The combs were analyzed in a BOD incubator with a digital thermographic camera FLIR (Series SC620). It was found that the contribution of metabolic heat by category and what differences occurred in thermogenesis within categories in different ranges of temperature (20 ºC, 25 ºC, 30 ºC and 35 ºC). Was Used as ambient temperature, the mean temperatures of the surrounding area to comb situated at 4cm from this and compared with the mean surface temperature (Tsc) of each category. The older stages of development showed greater thermogenesis than the younger, and the temperature range that had the highest mean gains of heat was at 35 °C with 0,38 °C (TOv) and 0,61 °C (TP3) as minimum and maximum, respectively. From range of 25 ºC, all categories showed means Tsc higher than their respective mean ambient temperatures. The mean temperature of the brood comb tends to increase the higher the number of cells containing older stages and decrease when there is the presence of younger individuals. Larvae and pupae contribute to their own thermoregulation through its thermogenesis, which is the only mechanism for heat production by the brood / O estudo da termorregulação em abelhas sem ferrão (Hymenoptera, Apidae, Meliponini) é essencial para melhor compreender a adaptação destes insetos ao ambiente às quais estão inseridos. Seu comportamento fisiológico quanto às diferentes temperaturas ajudam a entender a evolução da sua sociedade. Os mecanismos de trocas térmicas são estratégias importantes para garantirem a sobrevivência de uma espécie, principalmente para os indivíduos mais imaturos, ou seja, a cria. O presente trabalho foi realizado na Fazenda Experimental Rafael Fernandes, pertencente à UFERSA em Mossoró-RN, bioma Caatinga. Foram analisados 10 favos de cria de Melipona subnitida através da termografia, e aferido as temperaturas das superfícies das células separadas em 10 categorias, divididas em sete diferentes estágios de desenvolvimento de cria, células com indivíduos mortos, células vazias e células contendo larvas e pupas do parasita Plega hagenella. Os favos foram analisados em uma estufa BOD com uma termocâmera digital FLIR (Serie SC620). Verificou-se qual a contribuição de calor metabólico por categoria e quais diferenças ocorreram na termogênese dentro das categorias em diferentes faixas de temperatura (20 ºC, 25 ºC, 30 ºC e 35 ºC). Foi Utilizado como temperatura ambiente, as temperaturas médias da área circunvizinha ao favo situada a 4cm deste e comparada com as temperatura de superfície média (Tsc) de cada categoria. Os estágios de desenvolvimento mais velhos apresentaram maior termogênese do que os mais jovens, sendo que a faixa de temperatura que obteve maiores ganhos médios de calor foi a 35 ºC, com 0,38 ºC (TOv) e 0,61 ºC (TP3) como mínimo e máximo, respectivamente. A partir da faixa de 25 ºC, todas as categorias apresentaram Tsc médias maiores que suas respectivas temperaturas do ambiente. A temperatura média do favo de cria tendia a se elevar quanto maior for a quantidade de células contendo estágios mais velhos e diminuir com a presença de indivíduos mais jovens. Larvas e pupas contribuem para sua própria termorregulação através de sua termogênese, sendo este o único mecanismo para produção de calor por parte da cria
204

Influência de cores de E.P.Is (calças e luvas) na defensividade das Abelhas Africanizadas (Apis melífera L.) / Color influence gloves and pants on the defensive behavior of Africanized Honey Bees (Apis mellifera L.)

Dias, Victor Hugo Pedraça 29 July 2015 (has links)
Made available in DSpace on 2016-08-15T20:31:27Z (GMT). No. of bitstreams: 1 VictorHPD_DISSERT.pdf: 1381835 bytes, checksum: 57c84dd156bdf2a27e739f9bc6c2b2c4 (MD5) Previous issue date: 2015-07-29 / Scientific works on the defensive behavior of AHB-Africanized Honey Bees (A. mellifera L). show that they are more sensitive to dark color. Thus, the use of clothing and gloves with light colors should be an effective strategy to reduce defensiveness of these bees. However many beekeepers still use protective equipments not suitable as dark pants, dark gloves etc. This work aims to evaluate the influence of the colors of pants and gloves on defensiveness of AHB in order to guide the beekeepers about the most suitable protective clothing and gloves for handling these bees. The study was conducted at the CETAPIS bee yards, Experimental Station of UFERSA,in Mossoró-RN from September 2013 to May 2015. Three Langstroth hives were chosen, over 60 thousand bees each, with a high degree of defensive behavior (value of 4 on a scale of 1 to 4). For defensiveness testing the hives were handled without the use of smoke and the hives were stimulated with beats at the entrance and on the sides of the hives. After the bees became angry photographs of the experimenters were done. They wore three colored clothing (white, light blue and dark blue) and wore white gloves, yellow and dark green. The experimenters were posted in front of the hive for about 15 minutes for the photos. A white screen was placed (cloth) behind the experimenters to allow identification of bees around the body of the experimenters, pants and gloves. Each test was conducted four times throughout the day for each hive and for three consecutive days. 1059 comparative photos of pants and 4515 photos of the gloves were made. Photos of each comparative test were chosen at random among the best sharper photos. For comparisons were analyzed 36 photos of pants and 36 photos of the gloves. Bees were counted with the help of the program "Paint". For scores of bees identical areas were defined for each variable and all the bees were counted within their respective areas. The data were transformed to ensure normal distribution. The Tuckey test with 99% confidence level was applied. The white pants attracted an average of 40.28 +5.17 bees, light blue pants attracted 222.77 + 27.55 bees and dark blue pants attracted 392.60 + 78.67 bees. There was a statistically significant difference between the averages for the three treatments. As gloves, dark green attracted an average of 225.72 +35.99 bees, white gloves attracted 77.45 + 26.80 bees and yellow gloves attracted 99.20 + 22 82 bees. The differences between the three means were statistically significant, but there was no statistically significant difference between yellow and white. The results clearly demonstrated that the protective cloths (dark coloration pants) and dark green gloves attract more bees, which become more defensive. This experiment proved that the light-colored protective cloths were the most recommended in the management of Africanized bees, and one should avoid using dark clothes (pants, blouses, coats, overalls) and dark gloves. / Trabalhos científicos sobre comportamento de defesa das abelhas Africanizadas (AHB) (Apis mellifera L.) comprovam que elas são mais sensíveis a cor escura. O uso de vestimentas e luvas com cores claras deve ser uma eficiente estratégia para reduzir a defensividade dessas abelhas. No entanto, muitos apicultores ainda utilizam vestimentas não recomendadas, tais como calças e luvas de cores escuras.Este trabalho tem o objetivo de avaliar a influência das cores de E.P.Is na defensividade das abelhas Africanizadas (AHB)(A. mellifera L.) com vistas a orientar os apicultores quanto a vestimenta e luvas mais adequadas no manejo dessas abelhas. O trabalho foi iniciado em setembro de 2013 e a parte experimental conduzida entre abril e maio de 2015, no apiário do CETAPIS, instalado na Fazenda Experimental da UFERSA, em Mossoró-RN. Foram escolhidas 3 colmeias Langstroth com mais de 60 mil abelhas cada e com elevado grau de defensividade (valor 4 numa escala de 1 a 4). Para os testes as colmeias foram manipuladas sem fumaça e estimuladas com batidas no alvado e nas laterais da colmeia. Após as abelhas ficarem irritadas foram registradas fotografias dos experimentadores com roupas de 3 cores (calças brancas, azul claro e azul escuro) e luvas brancas, amarelas e verde escuro. Para as fotos os experimentadores ficavam postados na frente da colmeia por aproximadamente 15 minutos. Para as fotos foi colocado um anteparo branco atrás dos experimentadores para melhor identificação das abelhas. Cada teste foi realizado 4 vezes ao longo do dia, em cada colmeia e por três dias seguidos. Foram tiradas 1059 fotografias das calças e 4515 fotografias das luvas. Foram escolhidas ao acaso as fotos melhores e mais nítidas de cada teste comparativo, sendo avaliadas 36 fotos para a comparação de calças e 36 fotos para luvas. As abelhas registradas foram contabilizadas com o auxílio do programa Paint . Para as contagens de abelhas foram delimitadas áreas idênticas para cada comparação. Foram contadas todas as abelhas delimitadas dentro das áreas e calculadas as médias para cada variável. Os dados foram transformados para garantir a normalização e os testes estatísticos (Teste de Tuckey com nível de 99% de confiança). A calça branca atraiu uma média de 40,28 ± 5,17 abelhas, a calça de cor azul claro atraiu 222,77 ± 27,55 abelhas e a calça jeans azul escuro atraiu 392,60 ± 78,67 abelhas. Houve diferença estatísticaentre as três médias. As luva amarelas atraíram 99,20 ± 22,82 abelhas, averde-escura atraíram uma média de 225,72 ± 35,99 abelhas e as brancas atraíram 77,45 ± 26,80 abelhas. Houvediferenças estatísticasentre as três médias obtidas nas luvas, porém, não constataram diferenças estatisticas entre amarelas e brancas. Os resultados demonstraram claramente que calça de coloração azul escura bem como luvas de cor verde escura atraem muito mais abelhas, as quais se tornam mais defensivas. Este experimento comprovou que roupas claras, em especial calças brancas e luvas de cores claras (brancas ou amarelas) são as proteções mais recomendadas no manejo de abelhas Africanizadas, devendo-se evitar E.P.Isde cores escuras
205

Atividade de voo de Plebeia aff. flavocincta Apidae, Meliponini e sua relaçao com fatores abióticos / Flight activity of Plebeia aff. flavocincta (APIDAE, MELIPONINI) and its relationship with abiotic factors

Oliveira, Fabiano Luiz de 27 February 2016 (has links)
Made available in DSpace on 2016-08-15T20:31:29Z (GMT). No. of bitstreams: 1 FabianoLO_DISSERT.pdf: 1435099 bytes, checksum: b17929f018436cbdd2c8d22fb8f9caf0 (MD5) Previous issue date: 2016-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Stingless bee species that occur in the Brazilian semiarid region are adapted to the hot and dry climate of the region. Additionally, the availability of floral resources varies greatly throughout the year. Thus, climatic factors associated with variation in resource availability may be important determinants for the external activities of stingless bee colonies in this ecoregion. The foraging activities are critical for the maintenance of colonies, since they are important to supply the colonies with food (pollen and nectar) and materials for construction and defense of the colony (resin). In the present study, I analyzed the abiotic conditions, mainly external ambient temperature, nest-internal temperature and relative humidity, and investigated whether and to which extent these variables are related to and interact with the foraging activity of Plebeia aff. flavocincta in the Brazilian semiarid region, where these bees naturally occur. The peak foraging activity of the bees was in a temperature range between 32-34°C. The colonies of Plebeia aff. flavocincta intensified their nectar and pollen collection in months with elevated precipitation, when resources in the environment were abundant. In the dry period, by contrast, foraging activity was genearlly low. The colonies adjusted their foraging activity to the given climatic conditions, which points to behavioral adaptations of this bee species to the environmental unpredicatbility of the Brazilian semiarid region / Espécies de abelhas sem ferrão que ocorrem no semiárido brasileiro são adaptadas ao clima quente e seco dessa região. No semiárido brasileiro os recursos florais disponíveis para a alimentação das abelhas variam muito ao longo do ano. Os fatores climáticos associados à variação na disponibilidade de recursos podem definir as atividades externas das colônias. Esses atividades são fundamentais para a manutenção das colônias, uma vez que suprem a colônia de alimentos (pólen e néctar) e outros materiais para construção e defesa da colônia (resina) Nesse sentido, foi analisado as condições abióticas principalmente temperatura ambiental externa, interna e umidade relativa sendo verificado que estas variáveis estão relacionadas e interagem com atividade de voo de Plebeia aff. flavocincta no semiárido brasileiro e no bioma Caatinga onde estas estão inseridas. Também foi verificado que as condições abióticas que favoreceram o pico dos principais recursos coletados por estas abelhas estão em uma faixa de temperatura entre 32 a 34 °C. A atividade de voo de Plebeia aff. flavocincta aumenta as coletas intensificando suas atividades externas, quando há recursos em grande quantidade, como nos meses de maior precipitação principalmente no que refere-se aos principais recursos como pólen e néctar, já que neste período há uma maior oferta de recursos florais, enquanto no período seco, houve atividade, mas não na mesma intensidade. As colônias destas abelhas ajustam a atividade forrageira aumentando tanto a atividade individual como também a força de trabalho colonial e que portanto os resultados aqui encontrados sugerem ajustes comportamentais às variações ambientais da região semiárida em respostas as mudanças e demandas da colônia
206

O desvio reprodutivo se correlaciona positivamente com o parentesco genético e o sistema de acasalamento? Euglossa cordata (Hymenoptera, Apidae, Euglossini) como estudo de caso

Freiria, Gabriele Antico 26 June 2015 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-09-14T20:10:01Z No. of bitstreams: 1 TeseGAF.pdf: 2448190 bytes, checksum: 08c41156c28e3e99e6284a8c18acb2d2 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:49:11Z (GMT) No. of bitstreams: 1 TeseGAF.pdf: 2448190 bytes, checksum: 08c41156c28e3e99e6284a8c18acb2d2 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:49:17Z (GMT) No. of bitstreams: 1 TeseGAF.pdf: 2448190 bytes, checksum: 08c41156c28e3e99e6284a8c18acb2d2 (MD5) / Made available in DSpace on 2016-09-16T19:49:22Z (GMT). No. of bitstreams: 1 TeseGAF.pdf: 2448190 bytes, checksum: 08c41156c28e3e99e6284a8c18acb2d2 (MD5) Previous issue date: 2015-06-26 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The orchid bees have always been considered promising for studies of the evolution of social behavior and reproductive division of labor. This is due to the fact that the orchid bees are the only members not clearly eusocial in corbiculate clade. In this study, the correlation between genetic relatedness and reproductive skew was investigated in the genus Euglossa, one of the five genus of Euglossini tribe, in order to support the understanding of the evolution of reproductive division of labor in Euglossini. Among the five genera of Euglossini, Euglossa is the most suitable for studies on the evolution of reproductive division of labor, because in this genus can be found solitary, communal and primitively eusocial species. Twelve nests of Euglossa cordata (Linnaeus, 1758) were analyzed. In this species, the foundation process is solitary, but small colonies are formed during nest reactivations, with females establishing different types of associations, in which their relatedness differs. During reactivations, one of the females performs oophagy and then oviposition in brood cells previously operculated by another females, consequently leaving a larger number of offspring. The behavioral analysis associated with relatedness estimates, made through the use of microsatellite markers, indicated that the dominant female perform oophagy followed by oviposition in all operculated cells by the subordinated bees. The reproductive skew was complete, regardless of the type of association established between the interacting females, and so reproductive skew and genetic relatedness was not associated in this study. Furthermore, the nesting biology of Euglossa was also studied, given the information scarcity about the nesting process in most species already described for this genus. Using the technique of trap nests, 43 nests of Euglossa were sampled. This study provides new information on the nesting biology of this genus, especially with regard to natural enemies associated with nests. / As abelhas da tribo Euglossini sempre foram consideradas promissoras para estudos sobre evolução do comportamento social e divisão de trabalho reprodutivo. Isto decorre do fato dos Euglossini serem os únicos membros não claramente eussociais entre as abelhas corbiculadas. Neste estudo, foi investigada a correlação entre parentesco genético e desvio reprodutivo em uma espécie do gênero Euglossa, um dos cinco gêneros de Euglossini, visando subsidiar o entendimento da evolução da divisão de trabalho reprodutivo na tribo. Dentre os cinco gêneros de Euglossini, Euglossa é o mais indicado para estudos sobre a evolução de divisão de trabalho reprodutivo, pois neste gênero são encontradas espécies solitárias, comunais e primitivamente eussociais. Foram analisados doze ninhos da espécie Euglossa cordata (Linnaeus, 1758). Nesta espécie, o processo de fundação dos ninhos é solitário, mas pequenas colônias são formadas durante as reativações, com as fêmeas estabelecendo diferentes tipos de associações, nas quais o parentesco entre elas é distinto. Durante as reativações, uma das fêmeas realiza oofagias, seguidas de oviposições em células anteriormente operculadas por outras fêmeas, deixando um maior número de descendentes. As análises de comportamento, associadas a estimativas de parentesco, realizadas mediante o uso de marcadores microssatélites, indicam que as fêmeas dominantes realizam oofagia, seguida de oviposição, em todas as células operculadas pelas subordinadas. O desvio reprodutivo foi completo, independentemente do tipo de associação formada entre as fêmeas reativadoras e, portanto, não houve correlação entre parentesco genético e desvio reprodutivo. Além disso, a biologia de nidificação em espécies de Euglossa foi estudada, dada a escassez de informações sobre os hábitos e características do processo de nidificação na maioria das espécies já descritas. Utilizando a técnica de ninhos-armadilha, foram obtidos 44 ninhos de Euglossa. O estudo traz novas informações sobre a biologia de nidificação no gênero, principalmente no que diz respeito aos inimigos naturais associados aos ninhos.
207

Avaliação da agressividade de abelhas Apis mellifera L. africanizadas no sertão da Paraíba. / Evaluation of the aggressiveness of bees Apis mellifera L. africanizadas in the sertão of Paraíba.

SILVEIRA, Daniel Casimiro da. 23 May 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-23T12:18:27Z No. of bitstreams: 1 DANIEL CASIMIRO DA SILVEIRA - DISSERTAÇÃO PPGSA 2012..pdf: 2092343 bytes, checksum: f7b46d35c4259a923367cac1ba701149 (MD5) / Made available in DSpace on 2018-05-23T12:18:27Z (GMT). No. of bitstreams: 1 DANIEL CASIMIRO DA SILVEIRA - DISSERTAÇÃO PPGSA 2012..pdf: 2092343 bytes, checksum: f7b46d35c4259a923367cac1ba701149 (MD5) Previous issue date: 2012-12-14 / A agressividade das abelhas africanizadas é considerada por muitos apicultores como um forte aliado para se evitar roubo da sua produção. Este trabalho tem o objetivo de avaliar a agressividade das abelhas Apis mellífera L. Africanizadas no sertão paraibano, através de testes de comportamento defensivo, para a produção de abelhas rainha mansas e produtivas. A pesquisa foi realizada na UFCG – POMBAL – PB e nos municípios de Condado, Pombal e Sousa no sertão da Paraíba. Os apiários eram compostos por 30 enxames, alojadas em colmeias padrão Langstroth. Destas, foram selecionadas aleatoriamente 10 colônias. Os testes de agressividade foram realizados em cada colmeia escolhida em 3 repetições, nos horários de 07:00 às 10:00 horas (H1), de 12:00 às 14:00 horas (H2) e das 15:00 às 17:00 horas (H3), e nos períodos da estação chuvosa (Abril de 2012) e da estação seca (Agosto de 2012). A agressividade foi medida pelo método de Stort (1974) com algumas adaptações, onde foram feitas as seguintes observações: Tempo para o enfurecimento das abelhas; Tempo para ocorrer à primeira ferroada; Número de ferrões deixados na camurça presa em um recipiente circular; Número de abelhas que atacaram após 1 minuto; Distância que as abelhas perseguiram o manipulador, e tempo para a calmaria das abelhas na colônia. Os dados foram avaliados pelos programas estatísticos SAS versão 9.0 e SigmaPlot for Windows versão 12.0. Após análise da normalidade pelo teste de Shapiro-Wilk, e homogeneidade de variância por Bartlett, os parâmetros avaliados por análise de variância, seguida do teste de Tukey e suas inter-relações por meio do teste de correlação de Pearson. A análise dos dados pelo método de Ward são representados num dendrograma. Para o enfurecimento das abelhas observamos que no período de inverno nos horários compreendidos entre 7:00 às 10:00 horas e das 12:00 às 14:00 horas do dia com valores de, respectivamente, 4,03 e 3,46 s, sendo estes estatisticamente diferentes dos observados no período de 15:00 às 17:00 horas (2,56 s). No período de seca, observamos o menor tempo de enfurecimento no período de 12:00 às 14:00 horas e de 15:00 às 17:00 horas do dia (3,93 e 2,76 s), sendo o período de maior agressividade das abelhas. Quando comparado o comportamento das abelhas entre as estações chuvosa e seca, observamos que o tempo de enfurecimento das abelhas não diferiu estatisticamente no horário de 15:00 às 17:00 horas. Dentre todas as colmeias analisadas observamos que elas possuem características em comum, independente do local de origem, podendo agrupá-las de modo a qualificá-las como agressivas ou mansas / The aggression of Africanized bees is considered by many as a strong ally beekeepers to prevent theft of their production. This study aims to assess the aggressiveness of the bees Apis mellifera L. Africanized in the backlands of Paraiba, through tests of defensive behavior, for the production of queen bees calm and productive. The survey was conducted in UFCG - POMBAL - PB County and the municipalities of Pombal and Sousa in the backlands of Paraiba. Apiaries are composed of 30 clusters, housed in standard Langstroth hives. Of these, 10 colonies were randomly selected. The tests were carried out aggression in each hive chosen in 3 replications, in times of 07:00 and 10:00 hours (H1), from 12:00 to 14:00 hours (H2) and 15:00 to 17:00 hours (H3), and during winter (April 2012) and dry (August 2012). Aggression was measured by the method of Stort (1974) with some adaptations ours, where the following observations were made: Time for the fury of the bees; occur for the first time in a sting suede, number of stings left in suede trapped in a container circular, Number of bees that attacked after 1 minute; Distance bees chased the handler, and the time to calm the bees in the colony. Data were analyzed by SAS statistical software version 9.0 and SigmaPlot for Windows version 12.0. After analysis of normality by the Shapiro-Wilk test, and homogeneity of variance by Bartlett, the parameters evaluated by analysis of variance followed by Tukey's test and their interrelationships through the Pearson correlation test. Data analysis by the method of Ward are represented in a dendrogram. To the fury of bees observed that during winter in times ranging from 7:00 to 10:00 hours and from 12:00 to 14:00 hours of the day with figures of, respectively, 4.03 and 3.46 s, being statistically different from those observed in the period from 15:00 to 17:00 (2.56 s). During the dry season, we observe the shorter infuriating between 12:00 to 14:00 hours and from 15:00 to 17:00 hours of the day (3.93 and 2.76 s), being the period of greatest aggressiveness of bees. Compared bee behavior between the winter and dry, we observed that the time infuriating bees did not differ statistically between the hours of 15:00 to 17:00 hours. Among all analyzed hives observe that they have characteristics in common, regardless of place of origin and can group them in order to qualify them as aggressive or tame.
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Abordagem comparativa da maturação cuticular em abelhas sociais e solitárias utilizando-se RNA-seq, quantificação de hidrocarbonetos e microscopia eletrônica / A comparative approach of cuticular maturation in social and solitary bees using RNAseq, hydrocarbons\' quantification, and electron microscopy

Tiago Falcón Lopes 01 November 2016 (has links)
Diferenças no timing da melanização e esclerotização do exoesqueleto são evidentes quando se compara a morfologia externa de abelhas de hábitos sociais e as solitárias. A esta diferença convencionamos chamar de heterocronia da maturação cuticular, o termo heterocronia significando variações no tempo relativo, ou ritmo, de um evento ontogenético em relação ao ancestral ou entre taxons. Propusemos que as abelhas sociais, que após a ecdise permanecem na colônia por vários dias, alcançariam a maturidade de alguns sistemas orgânicos, entre eles o tegumento, muito mais tarde que as espécies de abelhas solitárias que ao emergir partem imediatamente para atividades extra-nidais. Neste contexto, o objetivo deste trabalho consistiu em testar esta hipótese utilizando o tegumento em maturação das espécies de abelhas sociais, Apis mellifera e Frieseomelitta varia, e da espécie solitária Centris analis, em estudos comparativos de expressão gênica, ultraestrutura e quantificação de hidrocarbonetos cuticulares (CHCs). Para isto utilizamos sequenciamento de mRNA (RNA-seq), microscopia eletrônica de transmissão (MET) e cromatografia de gás e espectrometria de massas (CG/MS). Os perfis de expressão de genes da via de melanização/esclerotização cuticular (ebony e tan) diferenciaram as espécies sociais da solitária, assim como a expressão de genes com função na via de metabolismo de quitina (Cda5, Idgf4 e chitooligosacchariodolytic-domain-like) e de genes codificadores de proteínas estruturais da cutícula (CPR14, CPR17, CPR18, CPR25, CPR23, CPR26, Apd-3 e Apd-like). Genes com função na regulação da maturação cuticular (FTZ-F1, E74, Hr46 e Hr4) se mostraram co-expressos nas espécies sociais e os perfis de expressão destes genes, exceto Hr46, e de outros reguladores (Ethr, Hr38, Rickets e Ptx-1) também diferenciaram as espécies sociais da solitária. Ressaltamos em nossas análises os genes do ciclo circadiano, cuja expressão tem relação com a deposição de quitina cuticular, além de genes de vias de pigmentação não melanínicas. As análises de MET, abrangendo outras três espécies de abelhas (Bombus brasilienses: primitivamente eussocial; Euglossa cordata: facultativamente social; Tetrapedia diversipes: solitária), mostraram diferenças consistentes entre a ultraestrutura e espessura das cutículas das espécies sociais e solitárias, o que reforçou nossos resultados de RNA-seq. A quantificação absoluta dos CHCs diferenciou as abelhas sociais da solitária, consistente com a hipótese de heterocronia da maturação cuticular e com os perfis de expressão de genes envolvidos na biossíntese de CHCs. Assim, além de desvendar transcriptomas de tegumento de três espécies de abelhas, a comparação da expressão gênica aliada à análise de ultraestrutura da cutícula e quantificação de CHCs levaram à caracterização de diferenças no processo de maturação cuticular entre as espécies sociais e solitárias / Differences in the timing of exoskeleton melanization and sclerotization processes are evident when comparing the external morphology of social and solitary bee species. Such differences may constitute a relevant example of cuticular maturation heterochrony, this term referring to a genetic change in timing of an ontogenetic process relative to an ancestor or between taxons. We proposed that social bees, which remain protected inside the colony for many days before initiating outside nest activities, would reach the maturity of some organic systems, such as the integument (epidermis and cuticle), later than solitary bees, which start such activities immediately after ecdysis. We tested this hypothesis in a comparative study of the developing integument of eusocial bees, Apis mellifera and Frieseomelitta varia, and the solitary bee Centris analis. Using RNA-seq, we verified that the expression profiles of genes involved in cuticular melanization and sclerotization (ebony and tan), chitin deposition and organization (Cda5, Idgf4, chitooligosacchariodolytic-domain-like), and cuticle formation (CPR14, CPR17, CPR18, CPR25, CPR23, CPE26, Apd-3, Apd-like) were positively, correlated between the two eusocial species, but not between the eusocial and the solitary species. Some of the genes with roles in regulating exoskeleton maturation (FTZ-F1, E74, Hr46, Hr4) were co-expressed only in the eusocial species. The expression profiles of these genes (except Hr46) and other regulatory genes (Ethr, Hr38, Rickets, Ptx-1) were also positively correlated exclusively in the eusocial bees. We also highlighted the expression of genes involved in non-melanin pigment production and the expression of circadian rhythm genes that could be related to chitin layers deposition. Transmission electron microscopy analysis of the integument of the two eusocial and the solitary bee species, in addition to other three bee species (the primitively eusocial Bombus brasilienses; the facultatively social Euglossa cordata; the solitary bee Tetrapedia diversipes), showed differences in cuticle ultrastructure and thickness, thus supporting the RNA-seq data. In agreement with our hypothesis, CHC quantifications were consistent with the expression levels of genes involved in CHC biosynthesis, thus differentiating the superficial cuticle layer of the eusocial and solitary species. Together, the integument transcriptomes, ultrastructure, and CHC quantification allowed us to characterize differences in the timing of cuticle maturation in social and solitary bees
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Abundância relativa, fenologia e visita ás flores pelos apoidea do cerrado da Estação Ecológica de Jataí - Luiz Antônio - SP / Relative abundance, fenology, flowers visit in the cerradso vegetation for aqpoidea in the Estação Ecológica de Jataí - Luiz Antônio - SP

Sidnei Mateus 17 April 1998 (has links)
RESUMO O trabalho foi desenvolvido em uma área de cerrado de 1 ha., localizada na Estação Ecológica de Jataí, no município de Luiz Antônio - SP. A fauna de abelhas e suas fontes de alimento foram amostradas quinzenalmente, durante dois anos de coletas (setembro de 1991 a agosto de 1993), foi estudada a sua composição, riqueza, abundância relativa, fenologia e visita às flores através de levantamentos padronizados. Foram coletados 3659 indivíduos, pertencentes a 142 espécies e a 57 gêneros de 6 famílias de Apoidea, sendo que Apidae foi a melhor representada em número de indivíduos e Anthophoridae em número de espécies. Com relação à fenologia, as espécies foram mais abundantes no período de menor precipitação (maio a novembro de 1992). As abelhas visitaram 72 espécies de plantas para a coleta de néctar, pólen e óleo. As famílias Asteraceae, Leguminosae e Bignoniaceae foram as melhores representadas em número de espécies. Didymopanax vinosum (Araliaceae) e Pyrostegia venusta (Bignoniaceae) foram as espéceis vegetais mais visitadas. Quanto à fenologia do florescimento, a maior diversidade de espécies de plantas floridas foi verificada no verão e outono; já no inverno, houve uma queda acentuada de espécies floridas. Estabeleceu-se como espécies dominantes de abelhas, aquelas que estiveram melhor representadas em número de indivíduos (Apis mellifera, Trigona hyalinata) e as espécies dominantes de plantas, aquelas que atraíram um número significativo de espécies de abelhas (Didymopanax vinosum, Pyrostegia venusta). Esses dados serviram para determinar os grupos de abelhas mais relacionados quanto às flores visitadas e os grupos de plantas mais semelhantes quanto aos visitantes. De um modo geral, os Apoidea mostraram-se generalistas na utilização de recursos, tendo sido encontrados em várias espécies de plantas. No entanto, algumas espécies de abelhas coletoras de óleo da família Anthophoridae (Centridini), mostraram preferência por flores de Byrsonima intermedia e Heteropterys byrsonimifolia (Malpighiaceae). / ABSTRACT The research was undertaken in a cerrado area (1 hectare) located at Estação Ecológica de Jataí, Luiz Antônio Municipality, São Paulo State, SE Brazil. Bees foranging for food on flowers were standardizedly sampled at every 15 days, for two years (September, 1991 to August, 1993). Host plants were sampled also. The study aims at an approach towards: faunal-floral composition, species richness, relative abundance, flower visiting habits, etc. Concerning bees, (Apoidea), 3659 individuals were collected which represent 142 species, 57 genera and 6 families. Among the collected families, Apidae representatives were the most abundant in number of individuals, while the Anthophoridae were top-ranked in number of collected species. Relatively to phenology, higher species-abundance peaks were connected to periods of less pluviosity, that is, from May to November, 1992. In their foraging for nectar, pollen and oil, sampled bees visited 72 plant species, among which Asteraceae, Leguminosae and Bignoniaceae were the best represent at specific level. Didymopanax vinosum (Araliaceae) and Pyrostegia venusta (Bignoniaceae) were the plants preferably visited. Concerning flowering phenology, flowers were most abundant during summer and autumm; conversely, winter-periods presented the lowest levels of flowering. Dominant bee species were considered as those best represented relatively to collected number of individuals (e.g., Apis mellifera, Trigona hyalinata). On the vegetation side, dominant plant species referes to those taxa which attracted the most significant number of bees (e.g., Didymopanax vinosum, Pyrostegia venusta). Such definitios were important to determine the connexions between bee groups-visited flowers; and, the relationships between plant groupsvisitors, as well. Since most species were found visiting several plant species, the sampled bees can be regarded as generalists, primarily. However, in their oil-collecting activity some Anthophoridae species (Centridini) showed remarkakle preferences relatively to Malpighiaceae flowers: Byrsonima intermedia and Heteropterys byrsonimifolia.
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Écologie et conservation des abeilles sauvages le long d'un gradient d'urbanisation / Ecology and conservation of wild bees along an urbanization gradient

Fortel, Laura 01 October 2014 (has links)
Depuis des années, on observe un déclin des insectes pollinisateurs. La perte d’habitats naturels, en partie liée àl’urbanisation, est considérée comme l’une des causes majeures de ce déclin. Des populations d’abeilles(Hymenoptera : Anthophila) se maintiennent cependant en milieux urbains. La structure de leurs communautés,ainsi que leurs comportements de butinage et de nidification peuvent être affectés par les perturbations liées àl’urbanisation. Notre objectif était d’évaluer l’ampleur de ces modifications et de comprendre leurs mécanismes enutilisant 24 sites dans le Grand Lyon localisés selon un gradient d’urbanisation croissante (mesurée par laproportion de surfaces imperméables). Nous avons analysé les réseaux d’interactions pour étudier les relationsflore-abeilles et nous avons mis en place des aménagements pour la nidification (carrés de sol et hôtels à abeilles)sur 16 sites urbains ou périurbains pour étudier la dynamique de nidification et son impact sur les populations.Nous avons capturé 16352 spécimens appartenant à 293 espèces, soit près du tiers de la faune françaised’abeilles. Les sites périurbains (avec environ 50% de surface imperméable) avaient la plus grande richessespécifique. Les abeilles à langue longue et les abeilles cavicoles étaient plus présentes dans les milieux urbanisés,mais la spécialisation des interactions plantes-abeilles est restée stable le long du gradient d’urbanisation. Ladiversité spécifique des abeilles était associée de façon positive avec la diversité florale, la durée de floraison desespèces végétales et/ou leur floribondité. Les communautés d’abeilles étaient dépendantes de ces trois facteurs etaussi des plantes spontanées (natives ou naturalisées) plus que des plantes horticoles (ornementales ou exotiques).Enfin, les aménagements pour la nidification ont été colonisés par une faune d’abeilles diversifiée. Hormis Osmiabicornis, les abeilles ne présentaient aucune préférence quant aux substrats dans lesquels elles nidifiaient. Même sil’urbanisation change la structure des communautés d’abeilles, nos résultats confirment qu’une diversité importanted’abeilles sauvages peut perdurer dans des milieux moyennement, mais aussi fortement urbanisés.Dans un contexte d’urbanisation croissante et de déclin des abeilles, il semble indispensable de mettre en placedes plans de gestion en faveur de ces insectes pollinisateurs sauvages en agissant sur l’étendue des surfaces fleuries,les continuités écologiques entre ces surfaces, et une gestion plus appropriée des parcs, jardins et espaces vertsurbains. La présence d’une grande diversité d’espèces y compris dans des milieux très anthropisés fait vraiment desabeilles un groupe phare pour sensibiliser les citoyens à la biodiversité et aux services écosystémiques / Evidence has been accumulating for years that pollinator populations are declining. The loss of natural habitats,in part linked to urbanization, is considered to be one of the major causes of this decline. Some bee populationspersist nevertheless in urban environments. The structure of their communities, as well as their foraging and nestingbehaviors can be affected by urbanization. Our objective was to assess the magnitude of these changes and tounderstand their mechanisms by using 24 sites located in the Grand Lyon along a gradient of urbanization(measured by the proportion of impervious surface). We analyzed interaction networks to investigate plant-beerelations, and man-made nesting structures on urban sites (squares of soil and bee hotels) to study nesting dynamicsand its relevance for bee populations.We collected 16,352 specimens belonging to 293 species. Periurban environments (i.e., with ca. 50% ofimpervious surface) had the greatest diversity of bees. Long-tongued bees and cavity nesting bees were moreprevalent in urban environments, but the specialization of plant-bee interactions remained stable along the gradientof urbanization. The species richness of the bee community was positively associated with floral diversity, theduration of flowering of plant species and/or their floribundity. Bee communities depended on these three factorsand also spontaneous (native and naturalized) plant species more than on horticultural plants (ornamentals andexotics). Finally, man-made nesting sites were colonized by a diverse bee fauna. Apart from Osmia bicornis, beesshowed no preference for the substrates in which they nested. Our work confirms that, even if urbanization changesthe structure of the bee communities, an important diversity of bee species can persist in periurban, but also urbanenvironments.In a context of increasing urbanization and declining bee populations, it appears essential to create managementplans for these wild pollinators by acting on the surface of flowering areas, the ecological network linking them,and the appropriate management of parks, gardens, and recreational areas. The presence of a diverse array of beespecies even in the most urbanized area makes these pollinators worthy of being a flagship group to raise theawareness of citizens about biodiversity and ecosystemic services

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