Tesis sobre el tema "Pollen"
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Capucho, Liana Carneiro 1984. "Diversidade morfológica de políades em espécies de Mimosoideae (Leguminosae) = Morphological diversity of polyads in Mimosoideae species (Leguminosae)". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315571.
Texto completoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-24T13:42:31Z (GMT). No. of bitstreams: 1 Capucho_LianaCarneiro_D.pdf: 7485279 bytes, checksum: b54a3fba348638fec00612447ae9cdb5 (MD5) Previous issue date: 2014
Resumo: Dentre os diversos tipos de agrupamento polínico, encontrados em 42 famílias de angiospermas, as políades são de interesse especial, pois são registradas para apenas quatro destas famílias e sua ocorrência pode ser associada a uma redução no número de grãos de pólen por antera em uma espécie. Em Leguminosae, a maior em número de espécies e a mais amplamente distribuída dentre as quatro famílias com políades, essas estruturas ocorrem na subfamília Mimosoideae. Este trabalho apresenta dados sobre a origem, o desenvolvimento e a diversidade morfológica das políades, em nível estrutural e ultraestrutural (Capítulo 1); sobre a origem do adesivo polínico em Calliandra brevipes, substância encontrada tipicamente em políades de espécies do gênero; além de dados sobre a origem e desenvolvimento da políade nesta espécie (Capítulo 2, já publicado); a morfologia e fertilidade polínica em espécies poliembriônicas de Inga (Capítulo 3); e um estudo aprofundado da morfologia incomum das políades em Parkia, em nível estrutural e ultraestrutural (Capítulo 4). As políades são estruturas peculiares e ainda muito pouco estudadas, e o presente trabalho vem prover dados essenciais para a compreensão da origem e morfologia destas estruturas, e de sua funcionalidade na reprodução de espécies da subfamília Mimosoideae em Leguminosae. Para um entendimento mais completo acerca da função, valor adaptativo e seleção dessas estruturas, com ocorrência tão restrita a determinados grupos de plantas, estudos acerca da fisiologia do pólen, interação pólen-pistilo e de viabilidade de embriões formados após a fertilização dos óvulos, são requeridos
Abstract: Among all different types of pollen aggregation, reported for 42 angiosperm families, polyads are of great interest, because they are reported for only four of these families and it is associated to a reduction on number of pollen grains per anther in a species. Among those four families, Leguminosae stands out because it is the most species-rich family and widely spread. In Leguminosae, polyads often occur in the subfamily Mimosoideae. This study highlighted new information on the origin, development and morphological diversity of the polyads, employing anatomic and ultrastructural analyses (Chapter 1); origin of pollen adhesive in Calliandra brevipes, sticky substance tipically found in Calliandra polyads, in addition to data on polyad origin and development (Chapter 2, already published); polyad morphology and fertility in polyembrionic species of Inga (Chapter 3); and a meticulous analysis of the peculiar morphology of Parkia polyads (Chapter 4). Polyads are peculiar and still not well-known structures, and this study aims to contribute with essential data for its origin and morphology understanding, and its functionality in the reproduction of species comprised by subfamily Mimosoideae, in Leguminosae. For a more complete understanding on the function, adaptive value and selection of these structures, that are restricted to certain groups of plants, studies are required on the physiology of pollen, pollen-pistil interaction and viability of embryos formed after fertilization of the ovules
Doutorado
Biologia Vegetal
Doutora em Biologia Vegetal
Souza, Cintia Neves de. "Palinotaxonomia em espécies brasileiras de Gloxiniinae com ênfase no complexo Mandirola-Goyazia /". Jaboticabal, 2017. http://hdl.handle.net/11449/151043.
Texto completoCoorientador: Andréa Onofre de Araújo
Banca: Maria Amélia Vitorino da Cruz-Barros
Banca: Vania Gonçalves Lourenço Esteves
Resumo: A subtribo Gloxiniinae é composta por 21 gêneros e cerca de 160 espécies. No Brasil, Gloxiniinae possui 16 espécies, distribuídas em oito gêneros, sendo três endêmicos, geralmente encontrados em afloramentos rochosos de cerrados, campos rupestres ou florestas de galeria. Foram estudados os grãos de pólen de dez espécies brasileiras de Gloxiniinae (Gesneriaceae) pertencentes aos gêneros: Chautemsia A.O.Araujo & V.C.Souza (1 sp.), Gloxinia L'Hér. (3 spp.), Goyazia Taub. (2 spp.), Mandirola Decne. (3 spp.) e Seemannia Regel (1 sp.) com o objetivo de contribuir para a caracterização taxônomica do grupo e uma melhor delimitação dos gêneros e/ou espécies, com enfoque para as populações do complexo Mandirola-Goyazia, pois os dois gêneros e as espécies incluídas nesse complexo não aparecem bem delimitados em estudos taxonômicos e trabalhos de filogenia, e essa dificuldade pode ser explicada por apresentarem distribuição simpátrica, morfologia floral e fenologia muito semelhantes. Os grãos de pólen foram acetolisados, medidos, fotografados em microscópia óptica, microscopia eletrônica de varredura e transmissão e descritos qualitativamente. Os dados quantitativos foram analisados através de estatísticas descritiva e multivariada. Para as espécies brasileiras de Gloxiniinae analisadas, foram observadas variações entre os grãos de pólen principalmente quanto ao âmbito, forma, comprimento, largura e extremidades dos colpos, presença ou não de margem, tipo de endoabertura e tipo de orname... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Gloxiniinae have 21 genera and about 160 species. In Brazil, Gloxiniinae has 16 species, distributed in eight genera, three of which are endemic, generally found in rock outcrops of cerrado, rupestrian fields or gallery forests. We studied the pollen grains of ten Brazilian Gloxiniinae (Gesneriaceae) belonging to the genera: Chautemsia A.O.Araujo & V.C.Souza (1 sp.), Gloxinia L'Hér. (3 spp.), Goyazia Taub. (2 spp.), Mandirola Decne. (3 spp.) and Seemannia Regel (1 sp.) with the aim of contributing to the taxonomic characterization of the group and a better delimitation of the genera and/or species, focusing on the Mandirola-Goyazia complex populations. The species of this complex are not well delimited in taxonomic studies and phylogeny works, and this difficulty can be explained by the sympatric distribution, and the floral morphology and phenology very similar. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. The quantitative data were analyzed by descriptive and multivariate statistics. We observed for the Brazilian Gloxiniinae species variations on the amb, shape, length and width colpi, colpi end, margo, endoaperture and ornamentation. For the 36 natural populations of Mandirola and Goyazia, qualitative data such as number and type of apertures, endoaperture, margo, ornamentaion and exine utrastructure are very similar, but we identify differences in amb, shape, le... (Complete abstract click electronic access below)
Mestre
Cardellach, Lliso Pau. "Análisis esporo-polínico de la miel y el propóleo, y su relación con el entorno". Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670125.
Texto completoEstudiar los productos de Apis mellifera derivados de recursos botánicos (miel, mielato, polen y propóleo), es útil para caracterizar y valorar los productos de la abeja de un territorio y para comprender las interacciones planta-polinizador. La melisopalinología tiene como objetivos la determinación geográfica y botánica de los productos apícolas, basándose en la presencia de tipos polínicos (TP). El primer objetivo de la presente tesis ha sido determinar qué plantas son útiles para A. mellifera en Catalunya, a través de una revisión bibliográfica y de observaciones in situ se ha elaborado una relación de 424 taxones útiles, de 114 familias Para el estudio melisopalinológico de las 51 mieles y 26 propóleos analizados en esta tesis se elaboró una palinoteca de referencia en base a los TP de los taxones de interés apícola de Catalunya. Como resultado del análisis melisopalinológico, se ha determinado el origen geográfico y botánico de mieles y propóleos, y se han identificado 156 TP de 74 familias. A través del análisis del espectro polínico de las mieles, se han tipificado distintos tipos de mieles, tanto multiflorales como monoflorales, de diferentes zonas geográficas y distintos años. Además, el análisis estadístico ha mostrado la existencia de diferencias significativas entre las mieles urbanas y el resto de mieles. En las mieles no urbanas, se han identificado 131 TP. Aunque los más frecuentes son autóctonos (Brassicaceae T., Coronilla T., Quercus perennifolio, Rubus T., Salix sp. y Ulex T.) la aparición de especies invasoras (como Ailanthus altissima) muestra su utilidad como recurso apícola, e indica que hay que tener en cuenta a este tipo de especies al establecer el origen geográfico y botánico de las mieles de un territorio. También, destacar la elevada presencia y porcentajes de TP como Cistus monspeliensis, Hedera helix, Rhamnus sp. y Salix sp., que podrían servir como indicadores para la tipificación geográfica de mieles de Catalunya. Por otro lado, se ve reflejada la importancia para A. mellifera de los ecosistemas de tipo matorral y herbáceo, así como que las abejas de la periferia de núcleos urbanos se adentran en las ciudades para alimentarse, mientras que las de colmenas urbanas pueden alejarse de la ciudad. En las mieles urbanas, de Barcelona y Viladecans, se han identificado 89 TP, tanto ornamentales como silvestres. La aparición de los TP Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. y Sophora sp., hacen patente la marcada influencia taxones exóticos. Por otro lado, la aparición de un alto porcentaje de taxones arvenses indica que A. mellifera los visita, y refleja la importancia de minimizar el uso de herbicidas, y la de adecuar suelos con este tipo de vegetación en ciudades. Referente a los propóleos, el espectro polínico refleja la variabilidad de paisajes y vegetación de Catalunya. Se analizaron 26 muestras que permitieron la determinación de 135 TP, de los cuales los más frecuentes fueron Asparagus sp., Brassicaceae T., Hedera helix, Quercus perennifolio y Rosmarinus officinalis. Además, las diferencias observadas en los propóleos de Catalunya en función de su color y textura, podrían estar relacionadas con el origen botánico de las resinas procedentes de Pinus sp., Quercus sp, Castanea sativa y Populus sp. Comparando las muestras de propóleo y miel de un mismo lugar, se observa que la riqueza y la diversidad polínica es mayor en propóleos que en mieles y, aunque existe relación entre sus espectros polínicos difieren en un 64.4%. Por ello, el estudio del espectro polínico de ambos productos aporta una información más precisa sobre la vegetación circundante de los colmenares, complementando y mejorando la determinación del origen geográfico de mieles, sobre todo, aquellas con una diversidad polínica muy baja.
The study of Apis mellifera products derived from botanical resources (honey, honeydew honey, corbicular pollen, and propolis) is useful to assess the quality of bee products in a territory and to better understand plant-pollinator interactions. The main objectives of Melissopalynology are the determination of the geographical and botanical origin of bee products, based on the presence of nectariferous and/or polliniferous pollen types (PT). The first objective of this thesis was to determine which plants are useful to A. mellifera in Catalonia, through a literature review as well as on-site observations has been obtained a list of 424 useful taxa from 114 families. For the melissopalynological study of the 51 honeys and 26 propolis analyzed in this thesis, a reference palinotheque was elaborated based on the list of the pollen types (PT) from the taxa with beekeeping interest in Catalonia. As a result of the melissopalynological analysis, the geographical and botanical origin of the honeys and propolis have been determined, and 156 pollen types of 74 families identified. Through the analysis of the pollen spectrum of honeys, different types of honey have been typified, both multifloral and monofloral, from different geographical areas and from different years. In addition, the statistical analysis has demonstrated the existence of significant differences between urban honey and other honey. In non-urban honeys 131 PT were identified. Although the most frequent are native (Brassicaceae T., Coronilla T., Quercus deciduous, Rubus T., Salix sp., and Ulex T.), the appearance of invasive species (such as Ailanthus altissima) shows it’s as apicultural resource, and indicates that this type of species must be taken into account when establishing the geographical and botanical origin of honeys from a given territory. Also, the high presence and percentages of PT such as Cistus monspeliensis, Hedera helix, Rhamnus sp. and Salix sp. could serve as indicators for the geographical classification of honey from Catalonia. On the other side, it has been reflected the importance for A. mellifera of shrubland and herbaceous ecosystems, as well as that honeybees located on the periphery of urban centers enter the cities to feed, and that bees from urban beehives can move outside the city. In the urban honeys from Barcelona and Viladecans, 89 PT were identified, both ornamental and wild. The presence of Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. and Sophora sp. reveal the marked influence of exotic taxa. On the other hand, the appearance of a high percentage of PT of weed taxa indicates that A. mellifera visits them, and reflects the importance of minimizing the use of herbicides and of implementing soils with this type of vegetation in cities. Regarding propolis, the pollen spectrum reflects the variability of landscapes and vegetation in Catalonia. 26 samples were analyzed, and 135 PT determined, of which the most frequent being Asparagus sp., Brassicaceae T., Hedera helix, Quercus deciduous and Rosmarinus officinalis. Furthermore, the differences observed in the propolis of Catalonia, on the basis of their color and texture, could be related to the botanical origin of the resins from Pinus sp., Quercus sp, Castanea sativa, and Populus sp. Comparing the samples of propolis and honey from the same place, it was observed that the richness and diversity of pollen is greater in propolis than in honey and, although there is a relationship between their pollen spectra, the pollen types differ by 64.4%. Therefore, the study of the pollen spectrum of both products provides more precise information about the surrounding vegetation of the beehives, complementing and improving the determination of the geographical origin of honey, especially those with a very low pollen diversity.
Landi, Lorrayne Albernaz Domingues Camilo. "Palinotaxonomia em espécies brasileiras do complexo Codonanthe-Codonanthopsis e gêneros relacionados /". Jaboticabal, 2017. http://hdl.handle.net/11449/151255.
Texto completoCoorientador: Alain Chautems
Banca: Cynthia Fernandes Pinto da Luz
Banca: Claudia Barbieri Ferreira Mendonça
Resumo: Palinotaxonomia em Espécies Brasileiras do complexo Codonanthe- Codonanthopsis (Gesneriaceae) e gêneros relacionados - Será estudada a morfologia dos grãos de pólen de 25 espécies brasileiras dos gêneros Codonanthe (Mart.) Hanst., Codonanthopsis Mansf., Nematanthus Schrad. e Paradrymonia Hanst., distribuídas em sua maioria em dois biomas, Amazônia e Mata Atlântica. O objetivo deste trabalho é contribuir com a caracterização palinológica, em busca de dados morfológicos que possam melhor definir as espécies estudadas, auxiliando dessa forma, o melhor entendimento das relações de parentesco entre os gêneros e na compreensão da distinção florística entre os respectivos biomas. Os grãos de pólen foram acetolisados, medidos e fotografados sob microscopia de luz, microscopia eletrônica de varredura e transmissão. Os dados quantitativos receberam tratamento estatístico e descritivos, adequado ao tamanho das amostras e foram submetidos a uma análise multivariada identificando caracteres polínicos importantes na distinção das espécies. Os resultados obtidos com este estudo confirma a diversidade polínica para a Gesneriaceae, como já relatado na literatura. Os caracteres que mais contribuíram para distinção entre os gêneros, que auxiliarão trabalhos evolutivos futuros, foram a ornamentação dos grãos de pólen e as características de abertura. As espécies de Codonanthe e Codonanthopsis apresentam ornamentação predominantemente microrreticulada, diferente de Paradrymonia e Nematanthus com ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Palynotaxonomy in Brazilian species of Codonanthe-Codonanthopsis complex (Gesneriaceae) and related genera - The morphology of the pollen grains of 25 Brazilian species Codonanthe (Mart.) Hanst., Codonanthopsis Mansf., Nematanthus Schrad. and Paradrymonia Hanst., distributed mostly in two biomes, the Amazon rainforest and Atlantic Forest. The objective of this study is to contribute with the palynological characterization, in search of morphological data that can better define the studied species, a, thus helping, the better understanding of kinship relations between the genera and in the understanding of the floristic distinction between the respective biomes. The pollen grains were acetolysed, measured and photographed under light microscopy, scanning electron microscopy and transmission. The quantitative data were submitted to a multivariate analysis, identifying pollen characters that were important for the species classification. The results obtained with this study confirm the pollen diversity for the Gesneriaceae, as already reported in the literature. The characters that contributed the most to distinguish between the genera, which will help future evolutionary works, were the ornamentation of the pollen grains and the aperture characteristics. The species of Codonanthe and Codonanthopsis present predominantly microreticulate ornamentation, different from Paradrymonia and Nematanthus with pollen grains mostly reticulate. For Paradrymonia, there were no variations in the ornamentation of the apocolpium and mesocolpium of its pollen grains; in Nematanthus we can see a variation in the pattern of ornamentation between the apocolpium and mesocolpium regions (from microreticulate, reticulate to foveolate). Pollen grains with colpate aperture were described for Codonanthopsis, and for Paradrymonia pollen grains colp... (Complete abstract click electronic access below)
Mestre
Tebbutt, Scott James. "Pollen-specific gene expression". Thesis, University of East Anglia, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334705.
Texto completoKitaoka, Traci Kimiko. "Bumble bee pollen foraging activation role of colony stores and pollen quality and odor /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1453656.
Texto completoTitle from first page of PDF file (viewed July 25, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 28-29).
Németh, M. Barbara. "Pollen Performance and Seedling Vigor in Laboratory and Natural Populations of Clarkia Unguiculata (Onagraceae)". Miami University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=miami1117816212.
Texto completoGessman, Daniel J. "Pollen Forecasting in Sarasota, Florida". Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6845.
Texto completoBanks, Hannah. "Pollen structure in Caesalpinioid legumes". Thesis, Oxford Brookes University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401805.
Texto completoLee, Christopher B. "Pollen-pistil interactions in nicotiana". Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6089.
Texto completoThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 4, 2009) Vita. Includes bibliographical references.
SALOMONI, ILARIA. "Identification and mapping of genes expressed in pollen and during pollen-pistil interaction in maize". Doctoral thesis, Università degli Studi di Milano, 2007. http://hdl.handle.net/2434/56654.
Texto completoFraleigh, Brad. "Contribution à l'étude de la fertilité du pollen de Mil (Pennisetum typhoides (Burm. ) Stapf et Hubb. )". Paris 11, 1985. http://www.theses.fr/1985PA112125.
Texto completoThe fertility of the pollen of pearl millet (Pennisetum typhoïdes) was studied fresh and after conservation. Several pollen fertility tests were used: Alexander’s stain, fluorescein diacétate staining, in vivo germination and seed set. Except for the first of these tests, the correlation between pairs of tests was positive and very highly significant. Pearl millet pollen stayed fertile for about 12 days in ambient conditions. Many pollen samples were stored at 3-5°C in 26-30%, 25-56% or 70-75% relative humidity. In storage, at best, pollen fertility persisted for over a year. Pollen fertility was influenced by genotype and the growth conditions of the pollen source plants, by harvesting methods, and by storage hygrometry. The mechanisms underlying pollen mortality were studied by examining death curves and by comparing the results of different fertility tests. The usefulness of the conservation of pollen fertility is discussed in relation to plant improvement and genetic resources management
Guo, Feng. "Investigation into the functions of the pollen specific genes PiVAMP721 and PiSCP1 in pollen tube growth". Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Dissertations/Fall2008/F_Guo_112608.pdf.
Texto completoPatel, Cheril y Gerardo Arceo-Gomez. "Understanding Variation in The Effects of Heterospecific Pollen Receipt: The Effect of Pollen and Recipient Traits". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/158.
Texto completoAbou, Chakra Oussama. "Allergénicité des Granules Cytoplasmiques de Pollen". Phd thesis, Université Paris-Diderot - Paris VII, 2009. http://pastel.archives-ouvertes.fr/pastel-00567120.
Texto completoAndwinge, Maria. "Reading Pollen Records at Peloponnese, Greece". Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-106735.
Texto completoClark, Craig Andrew. "Numerical simulations of maize pollen dispersal". [Ames, Iowa : Iowa State University], 2007.
Buscar texto completoFernández, José. "Anther and pollen development in barley". Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/13916/.
Texto completoRichardson, N. "Pollen accumulation in recent ombrotrophic peat". Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383509.
Texto completoHarley, Madeline Margaret. "Palm pollen and the fossil record". Thesis, University of East London, 1996. http://roar.uel.ac.uk/1274/.
Texto completoRoberts-Oehlschlager, S. L. "In vitro embryogenesis in barley pollen". Thesis, University of East Anglia, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382872.
Texto completoDutta, Rita Johanna. "Ultrastructure of mesozoic spores and pollen". Thesis, Aberystwyth University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400780.
Texto completoKaraman, Ali Emre. "Statistical aspects of automatic pollen identification". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366220.
Texto completoRichter, Robert, Michael Leitner y Gero Vogl. "Ragweed: diffusional spread and pollen load". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198548.
Texto completoPenny, J. H. J. "Early Cretaceous angiosperm pollen from Egypt". Thesis, University of Cambridge, 1986. https://www.repository.cam.ac.uk/handle/1810/273106.
Texto completoRichter, Robert, Michael Leitner y Gero Vogl. "Ragweed: diffusional spread and pollen load". Diffusion fundamentals 24 (2015) 42, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14560.
Texto completoAbou, Chakra Oussama. "Allergénicité dez Granules Cytoplasmiques de Pollen". Paris 7, 2009. https://pastel.archives-ouvertes.fr/pastel-00567120.
Texto completoGrass pollen is one of the most important aeroallergen vectors in Europe. It highly contributes to respiratory allergic diseases such as asthma or allergic rhinitis. In contact to water or airborne pollutants, pollen grains can release microparticles or pollen cytoplasmic granules. Because of their size (<5 μm), granules may penetrate deeper into the lungs than pollen grains and so, can induce stronger allergie responses. The aim of this study was to characterized allergic potential of pollen cytoplasmic granules along 3 axes: epidemiological, experimental and analytical. Results of the epidemiological study involve a possible effect of granules in the onset of allergic reparatory diseases, in particular asthma. In experimental part, the results show that granules induced allergic - both humoral and cellular - and inflammatory responses. These results are compared with whole pollen, on a good animal model of allergy, the Brown Norway rat. Finally, according to the results of the analytical study, both water-soluble and water-insoluble allergens of granules contribute to the allergenicity of these microparticules
Bolinder, Kristina. "Pollen and pollination in Ephedra (Gnetales)". Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140771.
Texto completoKanwal, Mehwish. "Wheat: Rust Resistance and Pollen Biology". Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/24710.
Texto completoFiacconi, M. "Cave pollen taphonomy in Kurdish Iraq". Thesis, Liverpool John Moores University, 2017. http://researchonline.ljmu.ac.uk/6712/.
Texto completoAmbika, Manirajan Binoy [Verfasser]. "Bacterial and Fungal Microbiota of Flower Pollen and Potential Impact on Pollen-related Allergies / Binoy Ambika Manirajan". Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1174142286/34.
Texto completoCIANI, FRANCESCO. "Urban pollen rain: the local and extra-local contribution to the airborne pollen record in Florence (Italy)". Doctoral thesis, Università degli studi di Ferrara, 2020. http://hdl.handle.net/11392/2488328.
Texto completoLe ricerche che compongono questa tesi hanno come argomento la pioggia pollinica nella città di Firenze studiata mediante differenti metodologie di analisi: trappole gravimetriche (cuscinetti di muschio) e volumetriche (campionatori di tipo Hirst). Attraverso queste due tipologie di campionamento è stato possibile stimare il tempo di accumulo dei granuli pollinici nei muschi, le differenze quantitative/qualitative ed il contributo locale ed extra-locale sulle quantità di polline, con particolare riferimento ai cipressi ed alla componente allergenica della pioggia pollinica. I cuscinetti di muschio raccolgono la pioggia pollinica in maniera continuativa, accumulando granuli per un intervallo maggiore di cinque anni. La composizione della pioggia pollinica è relativamente simile nelle due metodologie di campionamento, mentre si osservano differenze notevoli da un punto di vista quantitativo. Il maggior contributo locale è dovuto alla componente arborea che mostra un elevato effetto di prossimità sui valori pollinici registrati al suolo. L’interpolazione dei dati ha mostrato che l’accumulo di polline è irregolare dentro la città e confermato una forte correlazione con la presenza degli alberi ornamentali più diffusi in ambito urbano. Per quanto riguarda l’apporto extra-locale, le piante che crescono sulle colline a nord della città forniscono il contributo di polline più elevato, soprattutto quando il vento spira ad intensità elevate. Lo studio sui granuli pollinici di Cupressaceae ha permesso di stimare il loro tasso di accumulo a livello del suolo e l’effetto prossimità di queste piante sulle registrazioni. Il polline di cipresso è la maggiore componente della pioggia pollinica allergenica, sebbene le concentrazioni di polline di piante erbacee siano e si mantengano elevate nel corso degli anni.
BOUGHEDIRI, LARBI. "Le pollen de palmier dattier : approche multidisciplinaire, modelisation multiparametrique en vue de creer une banque de pollens". Paris 6, 1994. http://www.theses.fr/1994PA066059.
Texto completoSilva, Adriana de Castro Correia da. "Produção e qualidade de frutos de pitaya (Hylocereus undatus) /". Jaboticabal :, 2011. http://hdl.handle.net/11449/96942.
Texto completoBanca: Carlos Ruggiero
Banca: João Alexio Scapare Filho
Resumo: A procura cada vez maior por uma alimentação saudável e balanceada tem levado a um aumento no consumo de frutas e verduras, e a uma maior diversificação pelos consumidores. Em virtude disso, o consumo de frutas exóticas tem aumentado nos últimos anos, destacando-se, entre os produtos comercializados, a pitaya. Por ser uma cultura ainda incipiente no país, há a necessidade de estabelecimento de pesquisas quanto ao seu cultivo para dar suporte aos produtores. Neste sentido, este trabalho foi realizado com o objetivo de realizar a caracterização do ciclo de produção da pitaya vermelha (Hylocereus undatus) na região de Jaboticabal, SP e a frutificação e qualidade de frutos em função da fonte de pólen, do ambiente de cultivo e da época de produção. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 3X2X2 (três espécies doadoras de pólen: H. undatus, H. polyrhizus e Selenicereus setaceus, dois ambientes - condução sob tela plástica branca e preta, e duas épocas de polinização: março e abril), com quatro repetições. Observou-se que a emissão de gemas e o florescimento na cultura da pitaya ocorrem com a associação de altas temperaturas e precipitação, havendo constante emissão de botões florais durante os meses de novembro a abril, com pico de florescimento no mês de dezembro. O clone avaliado mostrou-se auto-incompatível, sendo necessária polinização cruzada, com pólen de outras espécies de pitaya para garantir a frutificação. As condições climáticas influenciaram diretamente do desenvolvimento e na qualidade dos frutos obtidos
Abstract: The increasing demand for a healthy and balanced diet has led to an increased on fruits and vegetables expenditure, and greater diversification by the consumer. As a result, consumption of exotic fruits has increased in recent years, especially the dragon fruit. Due of the fact that is a new crop in Brazil country, researches are needed about their cultivation to support their producers. Therefore, this study was conducted with the aim of assess the phenology of red dragon fruit (Hylocereus undatus) on Jaboticabal, Brazil, and the effect of pollen source, environment for cultivation, and time on fruit set and fruit quality. The experimental design was entirely randomized, in a 3 X 2 X 2 (three pollen sources: H. undatus, H. polyrhizus and Selenicereus. setaceus X two environment for cultivation - under plastic screen black or white, X two times of pollination: March and April) factorial arrangement, with 4 replicates. It was observed that the issue of floral buds and the bloom on dragon fruit culture occurs with a combination of high temperatures and rainfall, with constant emission of flower buds during the months from November to April, with peak bloom in December. The clone evaluated demonstrated self-incompatible, requiring cross-pollination with foreign pollen to ensure fruit set. The environmental conditions influences directly on fruit development and quality
Mestre
Salem, Mohammed A. "Screening soybean genotypes for high temperature tolerance by in vitro pollen germination, pollen tube length and physiological techniques". Diss., Mississippi State : Mississippi State University, 2005. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.
Texto completoO'ROURKE, MARY KAY. "THE IMPLICATIONS OF ATMOSPHERIC POLLEN RAIN FOR FOSSIL POLLEN PROFILES IN THE ARID SOUTHWEST (AEROBIOLOGY, PALAEOBOTANY, TAPHONOMY, PRESERVATION)". Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183868.
Texto completoAstini, Juan Pablo. "Managing maize pollen dispersal and out-crossing". [Ames, Iowa : Iowa State University], 2007.
Buscar texto completoKroeger, Jens. "Diffusion and flow in growing pollen tubes". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66841.
Texto completoLa croissance de cellules ayant une paroie cellulaire est due \'a la collaboration de processus physiques et chimiques menant \'a une déformation mécanique contrôlée de ces cellules. Les cellules végétales, par exemple, doivent augmenter la surface de leur paroie afin de croître. Ceci peut être accompli de façon uniforme appellée croissance diffuse ou par croissance apicale. La croissance apicale est caractérisée par une déformation mécanique qui est confinée à une région spécifique de la cellule, soit l'apex. La croissance apicale méne générallement à des paroies cellulaires de forme cylindrique. Elle est observée chez des cellules végétales telles que le tube pollinique ou des racines mais aussi chez des algues ou des hyphes fongiques. Le tube pollinique est une protubérance qui croît sur un grain de pollen. Lors de la fertilisation, son rôle est de s'allonger jusqu'à ce qu'il atteigne l'ovule de la plante hôte et de permettre le passage d'une cellule de sperme contenue dans le grain de pollen.Cette thése étudie les principes physiques qui contrôlent la croissance apicale d'une cellule végétale. Elle s'applique plus spécifiquement à la croissance d'un tube pollinique. Les trois systémes particuliers que nous étudierons concernent les effets élastiques et les potentiels électriques sur la diffusion d'ions, l'aggrégation de protéines et le flot visqueux dans les tubes de pollen en croissance. Un premier phénoméne, observé il y a une décennie, est l'oscillation dans le temps de la vitesse de croissance ainsi que de la concentration de calcium et de l'épaisseur de la paroie cellulaire d'un tube pollinique. Bien que les interactions entre toutes les composantes du tube pollinique sont complexes, nous avont démontré que quelles composantes, lorsque couplées de maniére adéquate, produisent l'oscillation stable observée en laboratoire.La c
Simoleit, Anke Erika Paula [Verfasser]. "Pollen in Städten / Anke Erika Paula Simoleit". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2018. http://d-nb.info/1176633848/34.
Texto completoWalker, Levi P. "Screening soybean lines for heat-tolerant pollen". Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13671.
Texto completoDepartment of Agronomy
William T. Schapaugh
Heat and drought stress are common problems for crops grown in Kansas. Rarely do these problems occur separately, more often than not they occur in tandem if not simultaneously. The interaction of heat stress and pollen germination was investigated in order to determine if a physiological screen was a feasible method of determining heat tolerance in soybean [Glycine max (L.) Merr]. Ten soybean lines (Group A) from the 2006 Northern Region Uniform Soybean Tests were analyzed over two years in four locations consisting of irrigated and dryland field environments, with an additional twenty lines (Group B) analyzed in the second year. Pollen was collected from plants and incubated at either 28o, 34o, or 38o C to determine pollen germination for optimal and stress-inducing temperatures. A three-way interaction of entry x incubation temperature x environment was observed, as well as significant differences among entries, incubation temperatures and environments. Average pollen germination for soybean entries ranged from 25% to 38% across three incubation temperatures and four environments in Kansas during 2006 – 07. The average environment effect for pollen germination ranged from 29% (dryland, 2006) to 34% (irrigated, 2007), while the average incubation temperature effect on pollen germination ranged from 25% (38oC) to 44% (28oC). This experiment has shown that increasing incubation temperatures significantly decreases pollen germination in vitro. It has also shown that soybean genotypes differ in pollen germination and that an in vitro screen can be used to characterize these differences. Further studies are needed to establish the relationship between pollen germination, seed set and seed yield in soybean. Work also needs to be completed to determine the proper sample size to adequately characterize differences in pollen germination so that performance differences among genotypes can be used as selection criteria in a plant breeding program.
Holmes, Phillip Lee. "An experimental approach to spore/pollen taphonomy". Thesis, Royal Holloway, University of London, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.734436.
Texto completoZhang, Zheng. "RESISTIVE PULSE SENSORS FOR POLLEN PARTICLE MEASUREMENTS". University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1145070142.
Texto completoSimoleit, Anke [Verfasser]. "Pollen in Städten / Anke Erika Paula Simoleit". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2018. http://d-nb.info/1176633848/34.
Texto completoCarroll, Mark J., Nicholas Brown, Craig Goodall, Alexandra M. Downs, Timothy H. Sheenan y Kirk E. Anderson. "Honey bees preferentially consume freshly-stored pollen". PUBLIC LIBRARY SCIENCE, 2017. http://hdl.handle.net/10150/624047.
Texto completoJones, Sandra. "Allergenic pollen concentrations in the United Kingdom". Thesis, London Metropolitan University, 1995. http://repository.londonmet.ac.uk/3262/.
Texto completoPandey, Pooja Verfasser], Nicolaus von [Akademischer Betreuer] [Wirén, Klaus [Akademischer Betreuer] Humbeck y I. [Akademischer Betreuer] Szarejko. "Chromatin modifications during pollen development and pollen embryogenesis in barley / Pooja Pandey. Betreuer: Nicolaus Wirén ; Klaus Humbeck ; I. Szarejko". Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2015. http://d-nb.info/1090786727/34.
Texto completoLi, Furong. "Pollen productivity estimates and pollen-based reconstructions of Holocene vegetation cover in Norhtern adn temperate China for climate modelling". Doctoral thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-59574.
Texto completoIossi, Emerson [UNESP]. "Morfologia floral e maturação fisiológica de sementes de tamareira-anã (Phoenix roebelenii O'Brien) - Arecaceae". Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/105257.
Texto completoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Os objetivos dessa pesquisa foram os de estudar a morfologia floral, o ponto de maturidade fisiológica das sementes de Phoenix roebelenii (tamareira-anã) e o período de colheita dos frutos, no qual as sementes apresentem máxima qualidade fisiológica. As flores femininas e masculinas foram esquematizadas com o auxílio de uma câmara clara acoplada ao estereomicroscópio. Os grãos de pólen foram observados e fotografados em microscópio eletrônico de varredura. Os frutos, a partir de sua formação, foram colhidos semanalmente, sendo as determinações feitas em laboratório. Os dados biométricos dos frutos e das sementes foram determinados com auxílio de paquímetro digital. Foram também determinados o teor de água, a matéria verde e a matéria seca dos frutos e das sementes, a porcentagem de germinação e o índice de velocidade de germinação das sementes. As variáveis que apresentaram crescimento em função do tempo foram ajustadas ao modelo logístico e aquelas com tendência decrescente em função do tempo foram ajustadas ao modelo exponencial decrescente. A morfologia das flores masculinas, femininas e dos grãos de pólen de P. roebelenii é bastante homogênea e confiável, podendo ser usada no reconhecimento e identificação dessa espécie, além de fornecer subsídios para estudos da sua biologia floral e reprodutiva. O ponto de maturidade fisiológica das sementes de P. roebelenii ocorreu aos 138 dias após a antese (d.a.a.), podendo o período de colheita ser estendido até os 194 d.a.a.
The objectives of this research were to study the floral morphology and the physiological maturation of Phoenix roebelenii seeds, for the determination of the ideal harvesting time. The pistillate and staminate flowers were schematized with a clear camera coupled to the stereomicroscope, and the pollen grains were documented by means of electronic spin microscope. The fruits, after its formation, were harvested weekly and they were evaluated at laboratory conditions. Biometrical data of the fruits and seeds were obtained. The moisture content, the fresh and dry weight from the fruits and seeds, and the seed germination and the speed of germination index (SGI) were also recorded. The variables which showed growth in function of the time were adjusted to a logistic model and the one's which exhibited a decrescent trend in the function of the time were adjusted to an exponential decrescent model. The morphology of the flowers, and of the pollen grains of P. roebelenii is sufficiently homogeneous and trustworthy, being able to be used for the recognition and identification of this species, besides supplying subsidies studies of its floral and reproductive biology. It was observed that the physiological maturation point of seeds of P.roebelenii occurred at 138 days after anthesis (d.a.a.), and the harvesting period could be extended up to 194 d.a.a.
Prieu, Charlotte. "Evolution et Developpement des grains de pollen chez les angiospermes". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS201/document.
Texto completoMulticellular organisms are morphologically very diverse at every scale, regarding size, color, and shape of individuals and of their different parts. Natural selection and developmental constraints influence evolution of these characteristics, on the short term as well as on the long term. The model chosen here to study form evolution is the pollen grain of flowering plants, which is very diversified morphologically. We focused on specific features called apertures, which are structures of the pollen wall involved in survival and reproduction. We studied aperture evolution at large taxonomic scale in angiosperms, and we showed that in spite of variations, two main pollen types dominate: a pollen with one aperture in Monocots and early diverging angiosperms, and a pollen with three apertures in Eudicots. The study of this pattern showed that the stasis of triaperturate pollen in Eudicots is likely due to stabilizing selection rather than developmental constraints. Experiments on Arabidopsis thaliana mutants also revealed that an increase in aperture number was associated with lower resistance to osmotic stress. This result could suggest that triaperturate pollen grains represent a good trade-off between survival and germination. Moreover, we focused on a particular pollen type with many apertures, to determine its distribution in angiosperms. This type of pollen has many origins, however it is seldom fixed at large taxonomical scale, suggesting the intervention of lineage selection, eliminating this pollen type in the long run
Waser, Nickolas M. y Mary V. Price. "Drought, pollen and nectar availability, and pollination success". WILEY-BLACKWELL, 2016. http://hdl.handle.net/10150/616997.
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