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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.
81

The external morphology of pseudopanurgus aethiops (cresson)

Hackwell, Glenn A. 01 July 1958 (has links)
In comparing the head of Pseudopanurgus with Anthophora and Apis, the general outline appears rather similar, the most significant variation being found on the posterior surface. Extending ventrally from the postoccipital suture to the dorsal wall of the proboscidial fossa is a suture known as the fused hypostomal suture. The hypostomal area is rather small and makes up only a small portion of the dorsal and lateral walls of the proboscidial fossa, the remainder being formed by the postgena. If this is correct, the hypostomal carinae (a term with which the author does not agree) are actually located on the postgena. From this characteristic alone it would appear that Pseudopanurgus is more specialized than Apis but more primitive than Anthophora. The first abdominal sternum appears to be membranous in Pseudopanurgus, suggesting a specialization over both Anthophora and Apis, where sclerotized areas are still present. Some of the abdominal terga of Pseudopanurgus have a longitudinal suture on the ventrolateral angle. This also, suggests a specialization not found in Anthophora or Apis. Rather large gonostyli were observed on the gonocoxites of the male genitalia. Volsella are also present in Pseudopanurgus.
82

A influÃncia da mata nativa na diversidade e abundÃncia de abelhas polinizadoras de cajueiros (Anacardium occidentale L.) em plantios comerciais / The influence of native forest in the diversity and abundance of pollinating bees of cashew (Anacardium occidentale L.) in commercial plantations

EpifÃnia Emanuela de MacÃdo Rocha 12 March 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho teve como objetivo conhecer a abundÃncia, diversidade e frequÃncia das abelhas visitantes florais em Ãreas de cultivo de cajueiro comercial prÃximo e longe de mata nativa. A pesquisa foi realizada de agosto a novembro de 2012, em pomares comerciais no municÃpio de Horizonte, CearÃ. A metodologia constou na marcaÃÃo de cinco diferentes gradientes de distÃncia (40m, 80m, 120m, 160m e 200m) da mata nativa em 10 Ãreas de cultivo de cajueiro anÃo precoce para a contagem e registro dos visitantes florais observados em 500 panÃculas durante o percurso de transectos realizado em seis horÃrios distintos (7h, 9h, 11h, 13h, 15h e 17h) a cada 15 dias . AlÃm disso, eram realizadas coletas com rede entomolÃgica em seis Ãrvores selecionadas, cinco minutos em cada Ãrvore, em Ãrea de 25m x 50m. Foram coletadas 368 visitantes florais entre abelhas sociais (331), abelhas solitÃrias (21) e outras espÃcies (16) visitantes florais nas panÃculas do cajueiro. A relaÃÃo entre a abundÃncia de insetos e horÃrio da coleta revela que para todas as abelhas coletadas, os horÃrios de 7h e 9h foram os que apresentaram a maior abundÃncia de insetos visitando as flores do cajueiro, principalmente de meliponÃneos. A frequÃncia de visitantes florais do cajueiro em 500 panÃculas nos meses de floraÃÃo, tanto em Ãreas com mata nativa quanto sem mata nativa, nÃo variou em funÃÃo do perÃodo de florada (p>0,05), da mesma forma que nÃo houve diferenÃa significativa (p>0,05) no nÃmero mÃdio de abelhas quando comparado as diferentes distÃncias durante as contagens nas Ãreas com mata nativa e sem mata nativa. As abelhas sociais foram as mais abundantes e destas, 176 foram Apis mellifera e 159 meliponÃneos. Jà as abelhas solitÃrias foram pouco representadas por coleta, tendo Centris spp. e Xylocopa (Neoxylocopa) cearensis sido vistas somente em algumas Ãreas de estudo, nÃo apresentando efeito significativo (p>0,05) quanto ao local (com ou sem mata nativa), Ãrea, horÃrio e dia de coleta. Conclui-se com esse estudo que a presenÃa do fragmento de mata nativa prÃxima à borda de cultura, nÃo influenciou na abundÃncia de visitantes florais nas distÃncias selecionadas, contudo a existÃncia de remanescentes de mata nativa prÃximo aos cajueirais, possibilitou a permanÃncia das abelhas sociais nas Ãreas de cultivo durante todo o perÃodo de florada, principalmente nos horÃrios em que as flores do cajueiro estÃo mais receptivas à polinizaÃÃo. / This study aimed to understand the abundance, diversity and frequency of bees visiting flowers in cashew tree growing areas near and far from commercial native forest. The research was conducted during the blooming season in 2012, from August to November in commercial orchards in the city of Horizonte, CearÃ. The methodology consisted in marking five different gradients of distance (40m, 80m, 120m, 160m and 200m) in all 10 areas to perform and record count of floral visitors in 500 panicles during transect conducted at six different times (7h, 9h, 11h, 13h, 15h and 17h), and captured with an insect net in six selected trees, five minutes at each cashew tree in an area of 25m x 50m. We collected 368 flower visitors among social bees (331), solitary bees (21) and other species (16) floral visitors in panicles of cashew. The relationship between insect abundance and time of collection reveals that for all bees collected, the hours of 7h and 9h of the morning were those with the greatest abundance of insects visiting the flowers of cashew mainly of stingless bees. The frequency of flower visitors in 500 cashew flowering panicles in the months, both in areas with native vegetation as no native forest, did not vary according to the period of flowering (p>0.05), just as there was no significant difference (p>0.05) in the mean number of bees compared the different distances during the counts in areas with native forest fragment and native forest without. Social bees were the most abundant group and among them 176 were Apis mellifera and 159 stingless bees. Solitary bees were poorly represented and Centris spp. and Xylocopa (Neoxylocopa) cearensis were seen only in a few areas showing no significant effect (p>0.05) on the site (with or without native forest), area, time and day of collection. We conclude from this study that the presence of native forest fragment near the edge of culture, did not influence the abundance of floral visitors on selected distances, however the existence of remnant native forest near the cashew trees, allowed to remain in social bees growing areas during the flowering period, mainly at times when the flowers of cashew are more receptive to pollination.
83

DECOUPLING OF NEOTROPICAL SEASONALLY DRY TROPICAL FOREST PLANT-POLLINATOR INTERACTIONS IN THE MIDST OF CLIMATE CHANGE

Wolanin, Theresa N. 30 July 2021 (has links)
No description available.
84

Molecular detection and genetic manipulation of the Black Queen Cell Virus.

Benjeddou, Mongi January 2002 (has links)
The South African isolate of the Black Queen-Cell Virus (BQCV), a honeybee virus, was previously found to have an 8550 nucleotide genome excluding the poly(A) tail. Its genome contained two ORFs, a 5'-proximal ORF encoding a putative replicase protein and a 3'-proximal ORF encoding a capsid polyprotein.<br /> <br /> A reverse transcriptase PCR (RT -PCR) assay was developed for the detection of BQCV and acute bee-paralysis virus (ABPV). Complete genomes sequences w ere used to design unique PCR primers within a l-kb region from the 3' end of both genomes to amplify a fragment of 70.0 bp from BQCV and 900 bp from ABPV. The combined guanidinium thiocyanate and silica membrane method was used to extract total RNA from samples of healthy and laboratory-infected bee pupae. In a blind test, RT-PCR successfully identified the samples containing BQCV and ABPV. Sensitivities were of the order of 130 genome equivalents of purified BQCV and 1600 genome equivalents of ABPV.
85

Bee botany in Tanganyika

Smith, Francis G. January 1956 (has links)
No description available.
86

Endothermy and thermoregulation in solitary bees

Stone, Graham N. January 1990 (has links)
This thesis examines the roles of endothermy and body size in the thermal biology of solitary bees (Hymenoptera: Apoidea) within the species Anthophora plumipes (Anthophoridae) Amegilla sapiens (Anthophoridae) and Creightonellafrontalis (Megachilidae), within the genus Anthophora, and over the Apoidea as a whole. The effects of body size, climate and sexual interactions on the biology of Anthophora plumipes were investigated in Oxford between 1987 and 1989. Both ambient temperature and body size had a significant effect on females' ability to forage, what time they initiated foraging in the morning, and the type and mass of provisions collected. The behaviour of males was also strongly dependent on ambient temperature, which affected not only when they emerged from their nest tunnels, but also how long they spent basking, when and where they fed, and whether they showed courtship behaviour. The activity patterns and behaviour of male and female A. plumipes over time were shown to correlate with a complex array of factors. Activity patterns of females depended on the quality of floral resources available at foraging sites, body mass, ambient temperature, the position of the female in her nest-provisioning cycle, and levels of male interference at foraging sites. Male behaviour not only depended on body size and ambient temperature, but also on which other bees (particularly male and female conspecifics) were encountered while patrolling food sources and at the nest site. Endothermy in bees is much more widespread than previously thought, and warm-up before flight was present to some degree in all the species examined. Levels of thermoregulation achieved, however, varied considerably between species. Warm-up rates in bees, and thoracic temperatures in free and tethered flight, are shown to depend on ambient temperature and body mass within a species (for temperate and tropical examples), across members of the genus Anthophora and across the Apoidea as a whole. The persistence of these relationships over a range of comparative levels suggests that they are of fundamental importance. The form of these relationships differs between families in the Apoidea, and significant patterns only emerge when a comparative technique controlling for phylogeny is applied. Furthermore, body temperatures may also depend, in at least some cases, on sex and there may be differences within a group of related species between provisioning and parasitic forms. The interaction of all these factors is complex, and the predictive value of a variable such as body mass does not always emerge unless sophisticated techniques are used to control for other variables. The errors associated with two common methods in the measurement of insect body temperatures have often been loosely discussed but rarely quantified. This thesis examines (a) the magnitude and possible effects of errors in 'grab-and-stab' measurement of body temperature, and (b) the errors in measurement of body temperature using fixed sensors linked by thermally conducting leads to measuring devices. In neither case do the demonstrated errors preclude use of the technique, but care with interpretation is required. In both cases, measurement of thoracic temperature in small bees involves the largest errors, and this is the most serious obstacle to comparisons of endothermic and thermoregulatory abilities over the full range of body sizes found in the Apoidea.
87

Análise histoquímica e molecular comparada do fluido espermatecal e da secreção das glândulas espermatecais das fêmeas e das glândulas de muco dos machos em três espécies de abelhas com diferentes níveis de sociabilidade /

Marcondes, Mateus. January 2013 (has links)
Orientador: Fábio Camargo Abdalla / Banca: Rogilene Aparecida Prado / Banca: Edmilson Amaral de Souza / Resumo: Nas abelhas, a espermateca, órgão responsável por estocar os espermatozoides e mantê-los viáveis após a cópula, está presente nas fêmeas da maioria dos insetos,. Associadas a estas, encontram-se as glândulas espermatecais, cuja função é sintetizar o fluido espermatecal no qual os espermatozoides ficam imersos. As rainhas das espécies de abelhas eussociais, pertencentes as tribos Apini e Meliponini, podem estocar os espermatozoides dos machos por anos devido a sua longevidade ser maior do que a de outras espécies de abelhas. Contudo, espécies que apresentam longevidade e taxa de oviposição menores, como é o caso, dos Bombini e das abelhas solitárias, também possuem glândulas espermatecais e espermateca, e mecanismos de preservação dos espermatozoides. Não se sabe ao certo como a espermateca conserva os espermatozoides e se a secreção das glândulas espermatecais são as únicas responsáveis pela formação do fluido espermatecal, o qual se supõe ser o responsável por manter os espermatozoides viáveis nas espécies de abelhas. O fluido espermatecal é formado também pelo conteúdo seminal dos machos, produzido por suas glândulas de muco. Em abelhas, a composição química e a função da secreção das glândulas espermatecais das fêmeas e das glândulas de muco dos machos ainda são pouco estudadas e não se tem nada conclusivo na literatura. Com o intuito de verificar se a organização social e o estado reprodutivo das abelhas refletem em diferenças no tipo de secreção contido nas espermatecas, nas glândulas espermatecais e nas glândulas de muco foi realizado um estudo comparado da histoquímica e do padrão de bandeamento proteico das glândulas de muco, bem como do conteúdo da vesícula seminal dos machos, juntamente com as glândulas espermatecais e do fluido espermatecal das fêmeas com diferentes... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Spermatheca is the organ responsable to store the sperm and keep it viable after the copula. In association with this organ, we can find the spermathecal glands, which synthesize the spermathecal fluid that maintains the sperm. The eusocial bee queens of Apini and Meliponini tribes can store the male sperm for years due to its longevity is bigger than the others bee species. However, species with smaller longevity and oviposition rates like Bombini and lonely bees also have spermatheca, spermathecal glands and sperm preserving mechanisms. It is not known for sure how the spermatheca preserves the sperm and if the spermathecal glands secretion is the only responsible for the spermathecal fluid generation, which is believed to keeps the sperm viable. Some studies show that the spermathecal fluid is also formed by male seminal content produced in mucus glands. The spermathecal glands function and chemical composition in female bees and the male mucus glands are still less studied and there is nothing conclusive in the literature. This study aims to verify if different oviposition rates, longevity and social organization reflects in thta different kinds of secretion contained in spermatheca, spermathecal and mucus glands. For this I made a compared study of the histochemistry and protein band pattern of: 1. mucus glands secretion; 2. male seminal vesicle content plus spermathecal glands secretion; and 3. female spermathecal fluid. This comparison was done in diverse sociability levels and fecundity conditions: virgins and inseminated; with three bee species: Centris (ptilotopus) scopipes - solitary, Bombus morio - primitively eusocial, and Melipona quadrifasciata anthidioides - advanced eusocial. M. quadrifasciata anthidioides males don't have mucus gland, so in this case the seminal vesicle content was analyzed / Mestre
88

Petal epidermal patterning & pollinator attraction

Reed, Alison January 2015 (has links)
No description available.
89

Relação entre o corpo gorduroso e a vitelogênese em fêmeas de Melipona quadrifasciata anthidioides Lep

Oliveira, Vagner Tadeu Paes de [UNESP] 16 March 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-16Bitstream added on 2014-06-13T19:40:31Z : No. of bitstreams: 1 oliveira_vtp_dr_rcla.pdf: 3167477 bytes, checksum: 7c78f3049a399eb9b91205136ee7ba11 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Nas abelhas eussociais há duas castas femininas, as rainhas que são responsáveis pela produção dos indivíduos que mantêm a população da colônia e fazem sua multiplicação e as operárias que compartilham entre si todas as tarefas de manutenção da colônia e das próprias atividades da rainha. Na espécie estudada, Melipona quadrifasciata anthidioides, uma abelha sem ferrão, as operárias normalmente produzem ovos em seus ovários na fase em que se ocupam do aprovisionamento das células de cria (operárias nutridoras), diferentemente de Apis mellifera em que feromônios da rainha são capazes de inibir a vitelogênese nos ovários das operárias. As diferenças funcionais entre rainhas e operárias em ambas espécies são controladas hormonalmente. O corpo gorduroso (CG) é um tecido constituído basicamente por um único tipo de célula designado trofócito, cuja função se assemelha em vários aspectos à dos hepatócitos. Os trofócitos ao mesmo tempo em que retiram substâncias da hemolinfa e as armazenam ou metabolizam, sintetizam outras que nela descarregam. Entre estas últimas está a vitelogenina, uma proteína precursora do vitelo acumulado pelos ovócitos durante a vitelogênese, como reserva para o futuro desenvolvimento do embrião. Neste trabalho a citoquímica dos trofócitos de rainhas virgens, fisogástricas e de operárias nutridoras foi estudada com microscopia eletrônica de transmissão (MET) e comparadas com a morfologia do desenvolvimento dos ovócitos no ovário com a finalidade de comparar a atividade dos trofócitos com a absorção de substâncias da hemolinfa pelo ovário. Em outra vertente a presença da vitelogenina foi pesquisada no CG e no ovário de ambas as castas, na tentativa de verificar se havia concordância quanto à produção da proteína nos trofócitos e sua presença nos ovários... / Eussocial bees have two female castes, the queens that are responsible for producing individuals that will keep the colony population and workers that share among them the tasks of colony maintenance and of the queen care. In the studied species Melipona quadrifasciata anthidioides, a stingless bee, workers normally produce eggs in their ovaries when they are provisioning the brood cells (nurse workers), differently from Apis mellifera, where pheromones from the queen are able of prevent the vitellogenesis in the workers ovaries. The functional differences between queens and workers are, in both castes controlled by hormones. The fat body (FB) tissue is constituted basically by a single kind of cell designated throphocyte whose function is similar in several aspects to the hepatocytes. The throphocytes at the same time that take substances from the hemolymph and storage or metabolize them also synthesize others that are discharged in the body fluid. Among these is the vitellogenin, a precursor protein of the yolk accumulated by oocytes during the vitellogenesis as a reserve for further development of the embryo. In this work the cytochemistry of trophocytes of virgin and physogastric queens and nurse workers was studied with transmission electron microscopy (TEM) and compared to the morphology of oocytes development in the ovary with the purpose of correlate morphologically the activity of trophocytes to the absorption of substances from hemolymph by the ovaries. The presence of vitellogenin was searched in the FB and ovaries extracts of both castes by electrophoresis, as an attempt to see if there was an agreement between production of the protein in the trophocytes and their presence in the ovaries. Finally, taking into account the action of the morphogenetics hormones over the trophocytes, these cells of both castes were incubated into medium containing juvenile hormones III... (Complete abstract, click electronic address below)
90

Neither this, nor that

Hochhalter, Elise 01 May 2018 (has links)
No description available.

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