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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Uso de abelhas sem ferrão (Meliponinae:Apidae) em casa de vegetação para polinização e produção de frutos com e sem semente de minimelancia [Citrullus lanatus (Thunb.) Matsum. &Nakai] / Use of stingless bees (Meliponinae: Apidae) in greenhouse For pollination and fruit production of seeded and Seedless mini watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai]

Bomfim, Isac Gabriel Abrahão January 2013 (has links)
BOMFIM, Isac Gabriel Abrahão. Uso de abelhas sem ferrão (Meliponinae:Apidae) em casa de vegetação para polinização e produção de frutos com e sem semente de minimelancia [Citrullus lanatus (Thunb.) Matsum. &Nakai]. 2013. 140 f. Tese (doutorado em zootecnia)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-04-08T17:25:53Z No. of bitstreams: 1 2013_tese_igabomfim.pdf: 1449717 bytes, checksum: 5c363ee9760d3cfcfebb1aed8f8f70f2 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-25T19:54:36Z (GMT) No. of bitstreams: 1 2013_tese_igabomfim.pdf: 1449717 bytes, checksum: 5c363ee9760d3cfcfebb1aed8f8f70f2 (MD5) / Made available in DSpace on 2016-05-25T19:54:36Z (GMT). No. of bitstreams: 1 2013_tese_igabomfim.pdf: 1449717 bytes, checksum: 5c363ee9760d3cfcfebb1aed8f8f70f2 (MD5) Previous issue date: 2013 / The aim of this thesis was to investigate the viability of using the stingless bees, Melipona subnitida and Scaptotrigona sp. nov. for pollination and fruit production of seeded and seedless mini watermelon (Citrullus lanatus) under greenhouse conditions. To this end, the floral biology and pollination requirements of seeded and seedless mini watermelon varieties were investigated, as well as the adaptive and foraging behavior of both meliponines. The experiment was carried out in a greenhouse situated in the city of Fortaleza-CE. The results revealed that the varieties studied were monoecious plants with diclinous flowers, and that the stigma of its pistillate flowers remained receptive throughout the anthesis, which was from 05:25 h to 14:20 h. The seeded varieties set fruits by geitonogamous and xenogamous pollination, within the same variety and between different diploid genotypes. In contrast, the seedless genotypes set fruits only by cross-pollination with pollen from seeded varieties. M. subnitida did not show any interest in the crop, under the experimental conditions. On the other hand, Scaptotrigona sp. nov. adapted well to the confinement and collected floral resources since the second day after its introduction. Scaptotrigona sp. nov. showed an essential behavior for the pollination of mini watermelon, as they visited, for direct collection of nectar, staminate and pistillate flowers of both diploid and triploid genotypes. The quantity and the quality of fruits resulting from the pollination of this bee did not differ significantly (P > 0.05) from the hand pollination. It was concluded that M. subnitida did not adapt to the mini watermelon cultivation in protected environment with cooling system, and the introduction of Scaptotrigona sp. nov. colonies, for pollination purposes, is viable in the commercial exploitation of seeded and seedless mini watermelon under greenhouse conditions. / O objetivo desta tese foi investigar a viabilidade da utilização dos meliponíneos, jandaíra (Melipona subnitida) e Scaptotrigona sp. nov. na polinização e produção de frutos de minimelancia (Citrullus lanatus) com e sem semente, sob cultivo protegido. Para tanto, foram investigados a biologia floral, os requerimentos de polinização das variedades de minimelancia, bem como o comportamento de adaptação e forrageamento, e a eficiência de polinização desses meliponíneos sob ambiente protegido. O experimento foi conduzido em uma casa de vegetação localizada no município de Fortaleza-CE. Os resultados revelaram que as variedades estudadas eram plantas monóicas com flores díclinas, e que o estigma de suas flores pistiladas permaneceu receptivo durante toda antese, a qual foi de 05:25 h às 14:20 h. As variedades com semente produziram frutos por meio da geitonogamia e da xenogamia, dentro da mesma variedade e entre diferentes genótipos diplóides. Diferentemente, os genótipos sem semente apenas formaram frutos por meio da polinização cruzada com pólen proveniente de variedades com semente. A abelha jandaíra não demonstrou nenhum interesse pela cultura diante das condições experimentais. Por outro lado, a abelha Scaptotrigona sp. nov. se adaptou bem ao confinamento e coletou recursos florais desde o segundo dia após sua introdução. Scaptotrigona sp. nov. mostrou comportamento essencial para a polinização da minimelancia, pois visitou, para coleta direta de néctar, flores estaminadas e pistiladas tanto dos genótipos diplóides quanto dos genótipos triplóides. A quantidade e qualidade dos frutos resultantes da polinização por essa abelha não diferiram significativamente da obtida pela polinização manual (P > 0,05). Conclui-se que a espécie de abelha M. subnitida não se adaptou ao cultivo de minimelancia em ambiente protegido com sistema de arrefecimento, e que a introdução de colônias Scaptotrigona sp. nov., para fins de polinização, é viável na exploração comercial da minimelancia com e sem semente em ambiente protegido.
12

Biossistem?tica do complexo Cryptanthus zonatus (Vis.) Beer

Magalh?es, Raissa Elizabeth de Castro 18 December 2013 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-10-26T20:38:34Z No. of bitstreams: 1 RaissaElizabethDeCastroMagalhaes_DISSERT.pdf: 2956084 bytes, checksum: 30ed0d43ac433b53772eebeed7a3cef9 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-10-26T21:28:15Z (GMT) No. of bitstreams: 1 RaissaElizabethDeCastroMagalhaes_DISSERT.pdf: 2956084 bytes, checksum: 30ed0d43ac433b53772eebeed7a3cef9 (MD5) / Made available in DSpace on 2015-10-26T21:28:15Z (GMT). No. of bitstreams: 1 RaissaElizabethDeCastroMagalhaes_DISSERT.pdf: 2956084 bytes, checksum: 30ed0d43ac433b53772eebeed7a3cef9 (MD5) Previous issue date: 2013-12-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPQ / A delimita??o taxon?mica ao n?vel de esp?cie em plantas n?o ? uma tarefa f?cil, devido ao grande polimorfismo dos vegetais. No presente trabalho objetivamos avaliar tr?s morfotipos (formas) de Cryptanthus zonatus (Vis.) Beer (Bromeliaceae, Bromelioideae) descritos na literatura, lan?ando m?o da biologia floral e fenologia, al?m da morfologia floral e anatomia foliar. As ?reas de realiza??o do estudo foram o Parque Estadual das Dunas de Natal e a Reserva Particular do Patrim?nio Natural da Mata Estrela, no munic?pio de Ba?a Formosa Rio Grande do Norte (RN). Para o estudo fenol?gico foram feitas visitas mensais durante o per?odo de um ano, onde foram feitas observa??es acerca das fenofases de flora??o e frutifica??o das popula??es das tr?s formas de C. zonatus. Para biologia floral, procurou-se avaliar dados como: tipo de visitante floral, volume e concentra??o de n?ctar e hor?rio de abertura e fechamento das flores. Flores das tr?s formas foram coletadas em campo, analisadas ao estereomicrosc?pio e as medidas das pe?as foram feitas com a ajuda de um paqu?metro. Cortes transversais e paradermais de folhas das tr?s formas foram feitos, corados e posteriormente analisados ao microsc?pio ?tico. Observa??es de cortes paradermais em microsc?pio eletr?nico de varredura tamb?m foram feitas. Todos os dados mostraram n?o haver diferen?as significativas entre as tr?s formas. Desse modo, conclui-se que n?o h? subs?dios para o reconhecimento dos tr?s morfotipos de C. zonatus como entidades taxon?micas, e que as ferramentas de fenologia, anatomia, biologia floral e morfologia floral n?o foram conclusivas para delimitar esses tr?s morfotipos. Ainda visando caracterizar melhor a Flora de Bromeliaceae do RN, foi tamb?m estudada a anatomia foliar de Orthophytum disjunctum, uma esp?cie de um g?nero irm?o de Cryptanthus, apenas recentemente documentada no semi?rido do RN. A compara??o anat?mica entre Cryptanthus e Orthophytum permitiu a separa??o dos g?neros com base na disposi??o dos est?matos e maior espessura do par?nquima aqu?fero. Durante os trabalhos de campo, foi poss?vel, ainda, documentar a primeira ocorr?ncia de Aechmea muricata no RN, na RPPN Mata Estrela, auxiliando no entendimento da distribui??o do t?xon, que encontra-se amea?ado de extin??o. / The taxonomic delimitation at the species level in plants is not an easy task due to the large polymorphism of plants. In this project we aimed to evaluate three morphotypes (forms) of Cryptanthus zonatus (Vis.) Beer ( Bromeliaceae, Bromelioideae ) described in the literature using fl oral biology and phenology, as well as flo ral morphology and leaf anatomy . These studies were conducted in the Parque Estadual das Dunas de Natal, Rio Grande Norte (RN) and Private Reserve of Natural Patrimony Mata Estrela , in the municipality of Ba ? a Form osa. The survey of the phenology of the morphotypes involved monthly specimen observation in the field, during one year. In each visit, we observed the status of flowering and fruiting phenophases of the population of the three forms of C. zonatus . For flo ral biology we sought to evaluate data like: observed floral visitors, nectar volume and concentration, time of anthesis and closing of flowers . Flowers of the three fo rms were collected in the field , analyzed by stereomicroscope, and measurements of the f loral pieces were made with the help of a caliper . Transversal and paradermal sections of the leaves of the three forms were stained and then examined under an optical microscope. Observations of the epidermis under scanning electron microscopy were also conducted. The three m orphotypes could not be sepated based on all evidence investigated. Thus, we conclude that there is not evidences to support the recognition of C. zonatus morphotypes as taxonomic entities, and also that the tools of phenology, anatomy, biology and floral morphology were not useful to delimit these three forms . Yet to characterize better the Flora of Bromeli aceae of RN, the leaf anatomy of Orthophytum disjunctum was also studied. Orthophytum is the sister genus to Cryptanthus and only recently documented in the semiarid of RN. The anatomical comparison between Cryptanthus and Orthophytum allowed the separatio n of both genera based on the arrangement of stomata and thickness of aquiferous par?nquima . During the fieldwork, it was still possible to document the first occurrence of Aechmea muricata in RN, inside the Mata Estrela preserve, aiding the understanding of the distribution of the taxon that is currently threatened with extinction.
13

Ecologia quimica de abelhas brasileiras : Melipona rufiventris, Melipona scutellaris, Plebeia droryana, Nannotrigona testaceicornis, Tetragonisca angustula e Centris trigonoides / Chemical ecology of Brazilian bees : Melipona rufiventris, Melipona scutellaris, Plebeia droryana, Nannotrigona testaceicornis, Tetragonisca angustula and Centris trigonoides

Pianaro, Adriana, 1981- 02 May 2007 (has links)
Orientador: Anita Jocelyne Marsaioli / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-10T12:24:10Z (GMT). No. of bitstreams: 1 Pianaro_Adriana_M.pdf: 2518438 bytes, checksum: 3b5f12bf2a708bd9e45fb606bde6a3a2 (MD5) Previous issue date: 2007 / Resumo: A vida social das abelhas é marcada pela presença de várias substâncias produzidas por suas glândulas exócrinas e endócrinas ou coletadas na natureza. Estes compostos são empregados principalmente por operárias, machos e rainha no reconhecimento de seus companheiros de colônia, acasalamento, defesa do ninho e marcadores de percurso. Entre as abelhas sociais brasileiras, as pertencentes à subfamília Meliponinae (Apoidea: Apidae) são extremamente importantes para a flora nativa, pois contribuem com 40-90% da polinização. Estas abelhas são denominadas meliponíneos ou abelhas indígenas sem ferrão, distribuídas em mais de 300 espécies que vivem exclusivamente nas regiões tropicais e subtropicais. Os meliponíneos vivem em colônias permanentes com divisões de castas (operárias, machos e rainha) e, por isso, produzem uma gama de substâncias responsáveis pelas divisões de tarefas e para manter a ordem dentro da colônia. Com a finalidade de contribuir na descoberta dos compostos utilizados na comunicação das abelhas brasileiras, este trabalho abordou três tópicos, revelando: 1) a "guerra" química desencadeada pela Melipona scutellaris Latreille, 1811 (Apidae: Meliponinae) contra as operárias invasoras de Melipona rufiventris Lepeletier, 1836 (Apidae: Meliponinae), sendo que as principais armas químicas foram a alteração da composição da cera de M. scutellaris, com grande produção de acetato de triacontanila, e a adição de terpenos e compostos fenólicos no batume, o que provavelmente acabou tornando o ninho pouco confortável e expulsando as operárias invasoras; 2) a diferenciação química das operárias e dos machos de Nannotrigona testaceicornis Lepeletier, 1836 (Apidae: Meliponinae) é principalmente relacionada a presença de acetato de geranil-geranila (operárias) e Z-9-nonacoseno (machos) em seus abdomes, e em Plebeia droryana Friese, 1900 (Apidae: Meliponinae), o tetradecanal (operárias) e um éster desconhecido (machos). As composições químicas das cabeças também diferenciam machos e operárias de ambas espécies: os constituintes principais nas operárias de P. doryana são a-copaeno, Ar-curcumeno, d-cadineno, 1-cis-calameneno e Z-9-octacoseno e nos machos de P. doryana são o 2-nonanol, dois ácidos alifáticos lineares (C14 e C16) e o acetato de octadecanila. Os constituintes das cabeças dos machos e das operárias de N. testaceicornis podem ser distinguidos pela presença de nonanal, a-copaeno, pentadecano, dois Z-9-alcenos (C23 e C25) e octadecenoato de hexadecenila (operárias). As ceras cuticulares das operárias de N. testaceicornis possuem dois Z-9-alcenos (C25 e C28), enquanto que as dos machos possuíam o 2-fenil-tridecano. Em P. droryana, as ceras cuticulares das operárias possuíam a-copaeno, Ar-curcumeno, 1-cis-calameneno, geranil-linalol, esqualeno e acetato de nerolidol, enquanto o hentriacontano está presente somente nos machos; e 3) a importância do óleo floral de Lophanthera lactescens Ducke (Malpighiaceae) para as operárias de Tetragonisca angustula Latreille, 1811 (Apidae: Meliponinae) e fêmeas de Centris trigonoides Lepeletier, 1841 (Anthophoridae: Centridini), as quais utilizam o mesmo no ninho. A coleta do óleo floral por estas abelhas foi confirmada analisando a parte externa dos abdomens das mesmas. O óleo floral tem como componente principal o ácido 3-acetoxi-octadecanóico. Trata-se do primeiro relato de coleta de óleos florais por operárias de Tetragonisca angustula. Estes estudos revelaram alguns compostos que são responsáveis pelas relações entre castas, espécies e planta/polinizador, mas muitas espécies de abelhas brasileiras ainda precisam ser estudadas para uma melhor compreensão de suas relações complexas e suas comunicações químicas / Abstract: The social life of bees is marked for the presence of many substances produced by their exocrine and endocrine glands or collected in the environment. These compounds are employed mainly for queen, male, and worker bees in the recognition systems of colony individuals, copulation, nest defense, and odor trail markers. Among the Brazilian social bees, the subfamily Meliponinae (Apoidea: Apidae) is extremely important for native flora, because the Meliponinae bees contribute with 40-90% of the pollinization. These bees are known as meliponine bees or stingless native bees. There are more than 300 species distributed exclusively in tropical and subtropical regions. The meliponine bees exist in permanent colonies with divisions of castes (workers, males and queen) and, therefore, they produce a great diversity of substances responsible for divisions of jobs to maintain the colony organization. The aim of this work was to contribute in the discovery of the compounds employed in chemical communication of Brazilian bees. Three main topics were investigated and revealed: 1) the chemical "war" unchained by Melipona scutellaris Latreille, 1811 (Apidae: Meliponinae) against the invader workers of Melipona rufiventris Lepeletier, 1836 (Apidae: Meliponinae), then the main weapons are related with wax composition alteration with large production of triacontanyl acetate by M. scutellaris. The batumen composition was also altered with the addition of terpenes and phenolic compounds that probably change the odor of M. scutellaris nest producing an uncomfortable atmosphere which induces the invader workers departure; 2) the chemical differentiation of workers and males Nannotrigona testaceicornis Lepeletier, 1836 (Apidae: Meliponinae) is mainly related for geranyl-geranyl acetate (workers) and Z-9-nonacosene (males) present in their abdomens, and in Plebeia droryana Friese, 1900 (Apidae: Meliponinae), there is tetradecanal in workers' abdomens and an unknown ester in the males' abdomens. The heads chemical compositions can also differentiate males and workers in both species: the main constituents in P. droryana workers are a-copaene, Ar-curcumene, d-cadinene, 1-cis-calamenene, and Z-9-octacosene and in males are 2-nonanol, two linear aliphatic acids (C14 and C16), and octadecanyl acetate. The heads of males and workers N. testaceicornis can be distinguished by the presence of nonanal, a-copaene, pentadecane, two Z-9-alkenes (C23 and C25), and hexadecenyl octadecenoate (workers). The cuticular waxes of N. testaceicornis workers have two Z-9-alkenes (C25 and C28), and the males have 2-phenyl-tridecane. In P. droryana, the cuticular waxes of workers have a-copaene, Ar-curcumene, 1-cis-calamenene, geranyl-linalool, squalene, and nerolidol acetate, while hentriacontane is present in the males waxes; and 3) the importance of Lophanthera lactescens Ducke (Malpighiaceae) floral oil to Tetragonisca angustula Latreille, 1811 (Apidae: Meliponinae) workers and Centris trigonoides Lepeletier, 1841 (Anthophoridae: Centridini) females, which is used in their nest construction. Confirmation that these bees gather the floral oil was obtained by analyzing their abdomens (external part), which revealed the presence of 3-acetoxy-octadecanoic acid, the main constituent of floral oil. Floral oil gathering by Tetragonisca angustula workers was not previously reported. We have thus revealed some compounds that are responsible for the relationships among castes, species and plant/pollinator, but many other Brazilian bees should be studied for a better understanding of their complex relationships and their chemical communications / Mestrado / Quimica Organica / Mestre em Química
14

Estudo dos caracteres florais associados à ornitofilia e quiropterofilia em espécies de 'Passiflora' (Passifloraceae) / Study of floral traits associated with ornithophily and chiropterophily in Passiflora species (Passifloraceae)

Rocha, Diego Ismael, 1986- 27 August 2018 (has links)
Orientador: Marcelo Carnier Dornelas / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T11:18:53Z (GMT). No. of bitstreams: 1 Rocha_DiegoIsmael_D.pdf: 4893065 bytes, checksum: 1f8621283157c9a9ebce9de36cac067a (MD5) Previous issue date: 2015 / Resumo: Em Passiflora, a grande variabilidade das estruturas florais e cores permitiu adaptação dessas espécies a diversos tipos de polinizadores. Em geral, espécies polinizadas pelo mesmo grupo de animais exibem um conjunto de caracteres que determinam esses sistemas de polinização. O presente estudo teve como objetivo caracterizar o desenvolvimento de estruturas florais peculiares de espécies do gênero (androginóforo e corona), bem como, os aspectos bioquímicos (cor, aroma e néctar) de espécies com diferentes sistemas de polinização (ornitofilia e quiropterofilia) e nos híbridos interespecíficos obtidos entre as mesmas. Nossas análises evidenciaram que a espécie ornitófila (P. coccinea - flor vermelha) e a espécie quiropterófila (P. setacea - flor branca) apresentaram caracteres morfológicos, bem como, a composição química do néctar contrastantes estando essas características florais de acordo com os seus sistemas de polinização. Nos híbridos, nem todas as características foram intermediárias, em relação às espécies parentais. O androginóforo curvo, comumente, observado em espécies do gênero polinizadas por morcegos foi atribuído como resposta à barreira física exercida pelo perianto e a redistribuição de auxina nos tecidos dessa estrutura. Com relação à cor, os híbridos apresentaram tonalidades de vermelho diferentes da coloração escarlate observada em P. coccinea. Porém, a diversidade de pigmentação caracterizada nestes genótipos de Passiflora pôde ser explicada pela combinação de moléculas específicas de antocianinas acumuladas em suas pétalas. Quanto à composição química do aroma, os híbridos apresentaram uma composição qualitativamente similar ao de P. coccinea, não sendo observados a herdabilidade de compostos característicos do aroma de P. setacea (benzenoides). Possível correlação entre cor e aroma foi sugerida. Acredita-se que esses resultados possam contribuir para a compreensão da evolução destes sistemas de polinização dentro do gênero Passiflora / Abstract: In Passiflora, the great variability of floral structures and colours allowed adaptation of these species to different types of pollinators. In general, species pollinated by the same group of animals exhibit a set of characters that determine these pollination systems. This study aimed to characterize the development of unique floral structures of the genus (androgynophore and corona), as well as the biochemical aspects (colour, scent and nectar) of species with different pollination systems (ornithophily and chiropterophily) and in interspecific hybrids obtained between of them. Our analyzes have shown that both, morphology and nectar composition from ornithophilous (P. coccinea - red flower) and chiropterophilous species (P. setacea - white flower) are contracting, and these resources according to their pollination systems. In hybrids, not all features were intermediate in relation to the parental species. The bend androgynophore, commonly observed in the Passiflora species pollinated by bats was assigned in response to the physical barrier exerted by the perianth and the redistribution of auxin in tissues of that structure. Regarding colour, the hybrids showed different shades of red staining in comparison to the scarlet red observed in P. coccinea. However, the diversity of pigmentation characterized in these Passiflora genotypes could be explained by the combination of specific molecules anthocyanins accumulated in their petals. Regarding scent composition, hybrids showed a similar composition to the P. coccinea and, it was not observed heritability of characteristic P. setacea compounds (benzenoids). Possible correlation between colour and scent has been suggested. It is believed that these results may contribute to understanding the evolution of these pollination systems within the genus Passiflora / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal
15

Floral Morphogenesis and Molecular Systematics of the Family Violaceae

Feng, Min 17 October 2005 (has links)
No description available.
16

The Decomposition of Nothofagus fusca Floral and Bark Litter

Smaill, Simeon John January 2001 (has links)
Nutrient cycles and budgets have been calculated for various ecosystems, but the impact of floral and bark litter decomposition on nutrient cycling has been little investigated. In this study, the characteristics and decomposition of floral and bark litter produced by Nothofagus fusca in the Lewis Pass Reserve, New Zealand, was investigated, using both field and laboratory studies. Nothofagus fusca floral litter production in 1999 was 734 ± 76 kg ha⁻¹. Floral production in 2000 was estimated to be approximately 1% of this mass, the considerable difference being due to mast flowering in 1999. The decay rate constant, k, for floral litter in the field was 0.94 ± 0.01, and mass loss after one year was estimated to be 61%. The input of nitrogen to the litter layer in Nothofagus fusca floral litter was 12 ± 1 kg ha⁻¹, and it was estimated that 65% of this nitrogen was released from the floral litter in the one year. Phosphorous input to the litter layer through Nothofagus fusca floral litter in 1999 was 0.8 ± 0.1 kg ha⁻¹, of which 69% was released in one year. It was estimated that in 1999 nitrogen and phosphorous inputs to the litter layer through Nothofagus fusca floral litter were 117% and 73% respectively of that through foliar litter. Four types of Nothofagus fusca bark were identified and further differences between bark types were confirmed by chemical analysis. Inner bark contained less nitrogen than outer bark, and was slower to decompose in microcosms, contradicting the findings of other research. Annual nitrogen and phosphorous inputs through the production of all types of Nothofagus fusca bark litter was estimated to be 1.0 kg ha⁻¹ and 0.2 kg ha⁻¹ respectively, although confidence in these values was low. Significant proportions of the nitrogen and phosphorous content in bark were water soluble. Field and laboratory experiments indicated net nitrogen immobilisation occurred in all bark litter types after one year in the field, while net release of phosphorous occurred after one year.
17

The regulation of flower development in indeterminate Impatiens balsamina L

Greville, Karen January 2001 (has links)
No description available.
18

Systematics of dioscoreales

Caddick, Lizabeth Rebecca January 2000 (has links)
No description available.
19

Desenvolvimento e morfologia da flor em espécies da tribo Dipterygeae (Leguminosae, Papilionoideae) / Floral development and morphology in species of Dipterygeae (Papilionoideae - Leguminosae)

Leite, Viviane Gonçalves 26 July 2012 (has links)
Espécies da tribo Dipterygeae apresentam morfologia floral interessante, em especial o cálice, bem diferente dos demais membros de Papilionoideae. Representantes desta tribo exibem cálice assimétrico, constituído por duas sépalas adaxiais muito grandes e livres, e três sépalas unidas na base, com lobos abaxiais em forma de pequenos dentes. Assim, este trabalho visa a elucidar a origem deste tipo de cálice, por meio do estudo do desenvolvimento floral dos três gêneros da tribo, representados pelas espécies Dipteryx alata Vogel, Pterodon pubescens (Benth.) Benth. e Taralea oppositifolia Aubl.. Pretende-se também fornecer dados de desenvolvimento floral com valores taxonômico e evolutivo potenciais para o grupo. Botões florais e flores foram dissecados e preparados para análises de superfície em microscopia eletrônica de varredura e anatômica em microscopia de luz. As flores das espécies estão organizadas em inflorescências racemosas indeterminadas, são perfeitas e zigomorfas. A sequencia de surgimento dos verticilos florais é semelhante nas três espécies: bractéolas, sépalas, pétalas, carpelo + primeiros primórdios de estames antessépalos, e estames antepétalos. Dois primórdios de bractéolas são iniciados assincronicamente em D. alata e simultaneamente em P. pubescens e T. oppositifolia; estas bractéolas recobrem o meristema floral; a iniciação dos cinco primórdios de sépalas é unidirecional modificada em D. alata, helicoidal em P. pubescens e sequencial/sequencial modificada em T. oppositifolia; a iniciação dos cinco primórdios de pétalas é simultânea; o primórdio carpelar surge concomitante à iniciação dos primeiros primórdios de estames antessépalos; a iniciação dos estames antessépalos é em ordem unidirecional tendendo para verticilada; os cinco estames antepétalos surgem por último. A fenda carpelar surge do lado adaxial, sendo orientada para a direita ou para a esquerda, no lado oposto ao de iniciação do estame antepétalo adaxial. O androceu é assimétrico. Os filetes fundem-se devido ao meristema intercalar, mas não completamente, formando uma bainha aberta ao redor do carpelo. O carpelo é central com estigma truncado em D. alata, capitado em P. pubescens e puntiforme em T. oppositifolia. O tipo de cálice é elucidado nos estádios intermediários do desenvolvimento floral: a sépala abaxial e as laterais não se alongam, fundem-se, resultando em três lobos diminutos; já as adaxiais se alargam muito e alongam, permanecendo livres. O crescimento avantajado das sépalas adaxiais decorre do aumento do número de camadas e volume das células epidérmicas e subepidérmicas marginais. As flores possuem um apêndice em suas bractéolas, sépalas abaxiais e laterais, pétalas e anteras, onde se localiza um canal secretor. Em T. oppositifolia estes apêndices não ocorrem nas bractéolas e anteras. Além de canais, cavidades secretoras estão presentes no mesofilo das bractéolas, nas margens das sépalas e no apêndice das anteras. As alas exibem esculturas do tipo lamelado em D. alata e T. oppositifolia e lunado em P. pubescens. A presença de um canal secretor no apêndice dos órgãos florais constitui uma provável sinapomorfia para Dipterygeae. Caracteres com valor diagnóstico para as espécies são: (1) iniciação dos primórdios de bractéolas, (2) iniciação dos primórdios de sépalas, (3) proeminência do apêndice da antera, (4) tipo de escultura presente nas alas, (5) formato do estigma, (6) comprimento do estipe, (7) pilosidade do ovário, (8) curvatura do estilete, (9) posição da nervura central e (10) tipo de fruto. / Representatives of the tribe Dipterygeae exhibit interesting floral features, in special considering the calyx, which is quite different from that exhibited by other papilionoids. The calyx is asymmetric, constituted by two adaxial very large free sepals, and three abaxial unite sepals with teeth-like lobes. Thus, this work aims to to elucidate the developmental vias of this type of calyx, by studying the floral development and morphology of three genera of the tribe, represented by Dipteryx alata Vogel, Pterodon pubescens (Benth.) Benth. and Taralea oppositifolia Aubl. Also, we intend to provide other data on floral development with taxonomic and evolutionary values. Buds and flowers were dissected and prepared for surface and anatomical analyses, under scanning electron and light microscopy, respectively. The flowers of all species are arranged in indeterminate racemes, are zygomorphic and perfect. The initiation of floral whorls is similar in the three species: bracteoles, sepals, petals, carpel + antesepalous stamens, and antepetalous stamens. The floral apex initiates two bracteoles asynchronously in D. alata and simultaneously in P. pubescens and T. oppositifolia; these bracteoles cover the floral apex; the order of initiation of five sepal is modified unidirectional in D. alata, helical in P. pubescens and sequential or modified sequential in T. oppositifolia; the five petals initiate in a simultaneous order; the initiation of the carpel is concomitant to that of the antesepalous abaxial stamens; antesepalous stamens initiates in tendencies towards whorled order, and the five antepetalous stamens arise later. A central carpel with truncate stigma occurs in D. alata, capitate stigma in P. pubescens and punctiform stigma in T. oppositifolia. The carpel cleft of all species arises in the adaxial side and is positioned to the right or the left opposite to the antepetalous adaxial stamen primordium. The androecium is asymmetric. The filaments fuse due to intercalary meristematic activity, but not completely, forming an open sheath around the carpel. The different type of calyx is elucidate by observing the intermediary stages of floral development: the abaxial and lateral sepals do not elongate, fuse, resulting in a united structure with three lower lobes, while the adaxial sepals enlarge and elongate, remaining free. The great growth of adaxial sepals results of the increasing in the number of layers and volume of marginal epidermal and subepidermal cells. Bracteoles, abaxial and lateral sepals, petals and anthers are appendiculate. In T. oppositifolia these appendices do not occur in bracteoles and anthers. One secretory canal is observed within each appendix. Besides secretory canals, secretory cavities are found in the mesophyll of bracteoles, in the sepal margins and in the anther appendices. The wings show sculptures of lamellate type in D. alata and T. oppositifolia and of lunate type in P. pubescens. The presence of secretory canal in the floral appendices can be considered a synapomorphy for the tribe Dipterygeae. Diagnostic characters for the species are: (1) order of bracteole initiation, (2) order of sepal initiation, (3) anther appendix salience, (4) pattern of wing sculpture, (5) stigma shape, (6) stipe length, (7) ovary hairiness, (8) style bend, (6) position of the central rib, and (7) type of fruit.
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Monitoring, assessing and evaluating the pollinator species (Hymenoptera: apoidea) found on a native brush site, a revegetated site and an urban garden

Cate, Carrie Ann 15 May 2009 (has links)
This research presents the findings of a pollinator diversity study that took place at three study sites. Although variation in pollinator diversity occurred between the three sites, fewer pollinators than expected were recorded from the La Joya Tract (revegetated site). Numerous genera and species were recorded from the Havana Tract (native site) as well as the Valley Nature Center (urban garden). In contrast, the La Joya Tract had a comparatively depauperate pollinator fauna. The numbers of pollinator genera and species recorded from the three study sites were decreased in comparison to the total number of genera and species recorded from Hidalgo County. Hidalgo County has 35 known genera and 75 species of bees documented to date. About 40% of the genera and 23% of the species recorded from Hidalgo County were recorded from the Havana Tract in this study, while a mere 8.5% of the genera and 4% of the species were reported from the La Joya Tract and 34% of the genera and 16% of the species were reported from the Valley Nature Center. Although the vascular plant species identified from these study sites were diverse, the floral rewards they provided yielded an insight as to what was going on in terms of pollinator diversity. Plants may yield nectar or pollen floral rewards or both in some cases to pollinators. The current study provides evidence that revegetation of land with plants that primarily provide nectar rewards will result in fewer observed bee taxa than from land revegetated with plants that provide a mix of nectar and pollen floral rewards.

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