Dissertations / Theses: 'Spores and pollen grains'

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Hassett, Maribeth O. "Analysis of the Hygroscopic Properties of Fungal Spores and Pollen Grains inside an Environmental Scanning Electron Microscope (ESEM)." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1461243940.

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Tahi, Ignace. "Palynologie et caractérisation de la matière organique des dépôts Albo/Aptien-Crétacé Supérieur du bassin sédimentaire de Côte d’Ivoire." Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS464.

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Les dépôts d’âge Albien-Crétacé supérieur de Côte d’Ivoire, offrent un potentiel important pour l’exploitation des hydrocarbures, car elles comportent à la fois des roches mères et des roches réservoirs. Les travaux palynologiques antérieurs menés dans ce bassin sédimentaire, et d’autres bassins marginaux du Golfe de Guinée, ont permis d’établir des échelles biostratigraphiques, opérationnelles pour l’exploitation, mais incomplètes et parfois incohérences entre elles et avec d’autres marqueurs temporels. Ce travail propose une révision complète des archives palynologiques de l’Albien et du Crétacé supérieur de Côte d’Ivoire, leur biostratigraphie, les paléoenvironnements et leur valeur pour l’exploitation pétrolière. 167 échantillons de carottes provenant de 20 sondages et un sondage de déblais de 98 échantillons, produits dans le cadre des activités de la société PETROCI, ont fait l’objet de cette étude palynologique. Le matériel a livré une diversité de kystes de dinoflagellés (46 espèces) et sporomorphes (148 espèces). Un inventaire qualitatif et quantitatif a été réalisé sur l’ensemble des échantillons. Treize biozones ont pu être caractérisées : la palynozone PCI-I à Cerodinium granulostriatum du Maastrichtien supérieur ; la palynozone PCI-II à Andalusiella ivoirensis du Maastrichtien inférieur ; la palynozone PCI-III à Xenascus ceratioides du Campanien supérieur à moyen ; la palynozone PCI-IV à Trichodinium castanea du Campanien inférieur ; la palynozone PCI-V à Oligosphaeridium complex du Santonien ; la palynozone PCI-VI à Droseridites senonicus du Coniacien ; la palynozone PCI-VII à Tricolpites microstriatus du Turonien ; la palynozone PCI-VIII à Classopollis classoides du Cénomanien supérieur ; la palynozone PCI-IX à Triorites africaensis du Cénomanien moyen ; la palynozone PCI-X à Elaterocolpites castelainii de l’Albien supérieur-Cénomanien inférieur ; la palynozone PCI-XI à Lusatisporis dettmannae- Callialasporites dampieri de l’Albien supérieur ; la palynozone PCI-XII à Appendicisporites spp.-Elaterosporites spp. de l’Albien moyen-supérieur et la palynozone PCI-XIII à Callialasporites trilobatus-Afropollis spp. de l’Albien moyen-inférieur. L’évolution des paléoenvironnements au cours du Crétacé s’accompagne d’une réduction de la microflore d’origine continentale, dominante à l’Albien, et de l’installation de conditions marines, pour atteindre des conditions de mer ouverte au Turonien. Le développement du phytoplancton alguaire d’origine marine s’amorce et évolue jusqu’au Maastrichtien. Quatre paléoenvironnements majeurs peuvent être différenciés d’après les assemblages palynologiques, en cohérence avec les données sédimentologiques : un environnement fluvio-lacustre à littoral marin est associé aux dépôts de l’Albien moyen-inférieur ; des conditions marines, néritiques internes caractérisent les dépôts de l’Albien moyen-supérieur à Cénomanien inférieur-Albien supérieur ; un environnement néritique interne à externe va régner du Turonien au Santonien et un environnement néritique externe à bathyal supérieur caractérisant le Campanien- Maastrichtien. Les analyses de la matière organique ont fourni des valeurs de l’Indice d’Hydrogène (IH) inférieures à 300 mg HC g/TOC dans les échantillons étudiés, et le type de kérogène indique une prédominance de matière organique de Type III susceptibles de renfermer des roches mères potentielles dans le Sénonien inferieur, Cénomanien et Albien. Les roches mères cénomaniennes et albiennes sont matures pour la génération des hydrocarbures
The deposits of Albian- Upper Cretaceous age in the Ivory Coast offer significant hydrocarbon potential. Previous palynological work carried out on this sedimentary basin does not provide consistent and complete biostratigraphic scales. 167 cores samples from 20 wells and a 98 ditch cuttings samples were the subject of this palynological study. The material yielded an abundance of dinocysts (46 species) and sporomorphs (148 species). A qualitative and quantitative inventory was carried out. For biostratigraphy, thirteen biozones were characterized: the palynozone PCI-I with Cerodinium granulostriatum from the Upper Maastrichtian; palynozone PCI-II with Andalusiella ivoirensis of the lower Maastrichtian; upper to middle Campanian palynozone PCI-III with Xenascus ceratioides; Early Campanian palynozone PCI-IV with Trichodinium castanea; Santonian palynozone PCI-V with Oligosphaeridium complex; palynozone PCI-VI with Droseridites senonicus of the Coniacian; the palynozone PCI-VII of Tricolpites microstriatus from the Turonian; Upper Cenomanian palynozone PCI-VIII with Classopollis classoides; palynozone PCI-IX with Triorites africaensis of the Middle Cenomanian; the PCI-X palynozone with Elaterocolpites castelainii of the Lower Cenomanian-Upper Albian; palynozone PCI-XI from Upper Albian with Lusatisporis dettmannae- Callialasporites dampieri; the palynozone PCI-XII of Appendicisporites spp.-Elaterosporites spp. for Upper-middle Albian and palynozone PCI-XIII of Lower-middle Albian with Callialasporites trilobatus-Afropollis spp. Climate change since the Albian sees the microflora of continental origin dominated until the establishment of marine conditions open to the Turonian. The development of algae phytoplankton of marine origin begins and evolves until the Maastrichtian. Four major paleoenvironments: an environment of fluvio-lacustrine facies with a marine littoral is associated with deposits of the Lower-middle Albian; an internal neritic environment characterizes deposits from the Upper-middle-Albian to Lower Cenomanian-Upper Albian; an internal to external neritic environment will reign from the Turonian to the Santonian and an external neritic environment to upper bathyal characterizing the Campanian-Maastrichtian will mark this climatic fluctuation. In general, the values of the Hydrogen Index (HI) are less than 300 mg HC g / TOC in the samples studied, and the type of kerogen indicates a predominance of organic matter Type III likely to contain source rocks in the Lower Senonian, Cenomanian and Albian. Cenomanian and Albian source rocks are mature for the generation of hydrocarbons

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Dutta, Rita Johanna. "Ultrastructure of mesozoic spores and pollen." Thesis, Aberystwyth University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400780.

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Crawford, Carlos. "Variations of Indoor and Outdoor Airborne Fungal Spores, Pollen." Cincinnati, Ohio : University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?acc_num=ucin1179518877.

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Thesis (M.S.)--University of Cincinnati, 2007.
Advisors: Tiina Reponen PhD, Sergey Grinshpun PhD, Linda Levin PhD. Title from electronic thesis title page (viewed June 3, 2009). Includes abstract. Keywords: (1-3)Beta-D-Glucan; pollen; fungal spores; variation. Includes bibliographical references.

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Prieu, Charlotte. "Evolution et Developpement des grains de pollen chez les angiospermes." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS201/document.

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Chez les organismes pluricellulaires, la diversité morphologique observée à tous les niveaux est frappante, que ce soit au niveau de la taille, des couleurs, ou de la forme des individus, et des différentes parties qui les composent. La sélection naturelle, ainsi que les contraintes développementales, influencent l’évolution de ces différents attributs, sur le court terme comme sur le long terme. Le modèle choisi ici pour étudier l’évolution des formes est le grain de pollen des plantes à fleurs, qui présente une très grande diversité morphologique. Nous nous sommes focalisés sur un caractère morphologique, les apertures, qui sont des structures de la paroi du grain de pollen impliquées dans la survie et la reproduction. Nous avons étudié l’évolution des apertures à grande échelle taxonomique chez les angiospermes, et nous montrons que s’il existe de nombreuses variations, deux types principaux dominent : un pollen à une aperture chez les Monocotylédones et les angiospermes divergeant à la base, et un pollen à trois apertures chez les Eudicotylédones. En étudiant la dominance du pollen à trois apertures, nous avons pu montrer que la stase chez les Eudicotylédones était vraisemblablement due à une sélection stabilisante plutôt qu’à des contraintes développementales. Nous avons également montré, grâce à l’utilisation de mutants de la plante modèle Arabidopsis thaliana, qu’un nombre d’apertures élevé est défavorable face à un stress osmotique, ce qui pourrait suggérer que les pollens triaperturés représentent un bon compromis entre survie et germination. Enfin, nous nous sommes intéressés à un type particulier de pollen possédant de nombreuses apertures, dont nous avons étudié la distribution chez les angiospermes. L’apparition de ce type de pollen est récurrente, mais il n’est que rarement fixé à grande échelle taxonomique, suggérant l’existence d’un mécanisme de sélection interphylétique éliminant ce type de pollen sur le long terme
Multicellular 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

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Mami, Leïla. "Biostratigraphie du crétacé du sud-est constantinois (Algérie) : dinokystes, spores et pollen." Reims, 1993. http://www.theses.fr/1993REIMS007.

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Une etude palynologique des sediments cretaces du sud-est constantinois basee sur deux sondages petroliers: manndra 1 (man1) et oued melah 1 (oum1), et trois coupes de terrain a permis d'approfondir nos connaissances concernant les spores, grains de pollen et surtout les kystes de dinoflagelles du cretace d'algerie. Un inventaire detaille des dinokystes, spores et grains de pollen fossilises dans les formations gafsa, zebbag et el aleg (d'age barremien? a santonien) a ete dresse: 50 genres et 83 especes de dinokystes ont ete reconnus ainsi que 30 genres et 30 especes de spores et pollen dans les 283 echantillons analyses. La distribution verticale de l'ensemble des formes observees nous a conduit a definir: 7 intervalles pour le sondage man1 et 5 pour le sondage oum1 a partir des dinokystes, 5 intervalles pour man1 et 6 pour oum1 a partir des spores et pollen. Une correlation entre les deux puits a pu etre etablie. Compte tenu des quelques donnees fournies par les foraminiferes et des extensions de certains dinokystes, spores ou grains de pollen, precisement connues en d'autres lieux, il a ete possible de proposer un age pour chacun de ces differents intervalles et par la meme pour les formations traversees par ces deux sondages voisins. Concernant les coupes de terrain, nos premieres investigations ont permis de paralleliser la distribution de quelques formes interessantes de dinokystes, spores ou pollen avec la zonation fondee sur les foraminiferes planctoniques. Une comparaison avec les microflores du maroc et de la libye a ete effectuee, et une caracterisation des paleomilieux a ete tentee au niveau du sondage man1

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Hawke, Philip. "The pollen and spores of metropolitan Cape Town and their relationship with meteorological conditions." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21887.

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Bibliography: pages 182-202.
Cladosporium, in general, is the dominant atmospheric fungal spore. Fungal spores are, quantitatively, the dominant partner in the atmosphere. Meteorological factors such as wind speed and wind direction, precipitation, temperature, relative humidity, atmospheric pressure and atmospheric stability have been identified as affecting air spora concentrations and an attempt is made to explain the relationships involved. A thorough review of particle behaviour and current sampling methods indicates that the Burkard volumetric sampler was best suited for airspora sampling in Cape Town. Results of the research confirm that Poacear is the dominant pollen, but basidiospores are the dominant nant spores in the atmosphere.

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Tweddle, John C. "A high resolution palynological study of the Holocene vegetational development of central Holderness, eastern Yorkshire, with particular emphasis on the detection of prehistoric human activity." Thesis, University of Sheffield, 2000. http://etheses.whiterose.ac.uk/3507/.

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Compared to upland areas and Scotland, the Holocene vegetational history of lowland England is poorly known. This is particularly the case for the region of Holdemess, eastern Yorkshire, where only a low number of poor temporal resolution pollen diagrams have been published, none of which include analysis of microscopic charcoal content. The records are also largely undated and as a result reliable correlation between sites is not possible, and the timings of the key vegetation changes recorded in the data remain unknown. In this study, high resolution pollen and charcoal records were produced from four small (24 ha) infilled basins located within central Holderness. Complementary techniques of percentage loss-on-ignition and pollen preservation analysis were also employed, and a comprehensive radiocarbon-dating programme was undertaken to provide a secure chronological framework. The palaeoecological records produced provide a high temporal resolution reconstruction of the Holocene development of central Holderness, particularly during the Early-Mid Holocene, and allow consideration of the changing roles that ecological interactions, climate, and human influence have played in determining the Holocene vegetational composition of the region. A number of significant landscape-scale disturbances of inferred anthropogenic origin were identified from ca 9290 BP onwards and shown to vary significantly in timing, duration and character between sites. It is proposed that this palaeoecological data can be used to supplement the poor archaeological record of the area. Several key issues including the role of climatic instability in determining vegetational composition during the Early Holocene, the interpretation of incidences of cereal-type pollen, the use of the charcoal record as a proxy indicator of human activity, and the use of pollen preservation analysis as an interpretational tool are also considered.

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Coetzee, Kim. "Evaluation of the crossability between small grains." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17796.

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Lee, Taekhee. "Bioaerosols in Homes Without Visible Mold Growth: Relationship Between Indoor and Outdoor Levels Determined by Different Methods." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1154619575.

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Wenzel, Carol Lorraine Carleton University Dissertation Biology. "Development of anthers and pollen grains of Brassica Napus L.; a histological and histochemical study." Ottawa, 1991.

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Ussama, Elbastaweesy Mohammed Hirhish. "Study on the biological air quality in Bellaterra (Barcelona) and Vitoria-Gasteiz: pollen and spores and their allergens." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/666755.

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Los alérgenos aerovagantes están entre las partículas atmosféricas con mayor influencia en la salud respiratoria humana. La alergia al polen de Poaceae y al polen de Betula se encuentran entre las alergias respiratorias más importantes en Europa. Phl p 5 es el principal alérgeno y uno de los más representativos del polen de las especies de la familia Poaceae. Su alérgeno Phl p 5 es responsable del 88,4% de los casos de alergia en Europa. Bet v1 es el principal alérgeno y el más representativo del polen de la especie Betula. El polen de abedul provoca síntomas en el 10-20% de los pacientes alérgicos en los países del norte de Europa. Alt a 1 es el alérgeno mayor y el más representativo de las esporas del género Alternaria. A nivel mundial, su incidencia alérgica varía entre 4 y 40 % de los pacientes atópicos. Este estudio se enfocó, por primera vez, en la detección y cuantificación en base a datos diarios de los alérgenos Phl p 5, Bet v 1 y Alt a 1 en Bellaterra (Barcelona) y Vitoria-Gasteiz, dos localidades en el Norte de España, en los años 2013-2015. Estableció también su correlación con las concentraciones diarias de los correspondientes tipos de polen (Poaceae y Betula) y esporas (Alternaria) así como con los pólenes con reactividad cruzada. Se ha hecho también la correlación con Temperatura (máxima, mínima y media), Precipitación, Humedad Relativa y PM10. El método usado para la detección de alérgenos, captador multi-vial ciclón, se ha mostrado eficiente para capturar alérgenos de polen, pero no para muestrear alérgenos fúngicos. Para muestrear Alt a 1 se probó con un captador de partículas en suspensión de alto volumen (TPS). Análisis ELISA fue el método usado para cuantificar Phl p 5 y Bet v 1. Alt a 1 no pudo ser identificado con este método en las muestras obtenidas del captador ciclón, pero sí en las obtenidas con el TPS. La detección de Alt a 1 en las muestras TPS usando Dot-Blotting resultó ser el método más sensible a la detección de este alérgeno. La cantidad total anual de Phl p 5 y Bet v 1 variaron de un año a otro y de una localidad a otra. La Integral Anual de Alérgeno (suma de las concentraciones diarias) en 2015 fue 10 veces menor que en 2013 y 2014, respectivamente. El polen de Poaceae fue detectado en días en que no se detectó Phl p 5 mientras que Bet v 1 fue detectado en días en que no había polen de Betula. Se encontró una correlación positiva entre las concentraciones diarias de Phl p 5 y el polen de Poaceae en Bellaterra (Barcelona), años 2013 y 2015. También, se observó una correlación positiva entre las concentraciones diarias de Bet v 1 y polen de Betula en Vitoria-Gasteiz, año 2015. Pero, no se encontró ninguna correlación entre las concentraciones diarias de Bet v 1 y el polen de Betula en Bellaterra (Barcelona), años 2014 y 2015. Para explicar la presencia de Bet v 1 en la atmósfera fuera del período de polinización de Betula, se calcularon las correlaciones entre las concentraciones del alérgeno y las de los pólenes que presentan reactividad cruzada con ella: Alnus, Castanea, y Corylus. Se encontró correlación entre las concentraciones diarias de polen de Quercus y Bet v 1 en Bellaterra (Barcelona), año 2015, pero no en el 2014 ni en Vitoria-Gasteiz 2015. Las concentraciones diarias de Phl p 5 y Bet v 1 no mostraron correlación con los parámetros meteorológicos (Temperatura máxima, mínima y media, Precipitación, Humedad Relativa) pero sí se observó una correlación positiva de éstos en Bellaterra (Barcelona) y las concentraciones de PM10 de Montcada.
Airborne allergens are major players between the airborne particles that have influence on respiratory human health. Allergy to Poaceae pollen and to Betula pollen are between the most important respiratory allergies in Europe. Phl p 5 is the major allergen and one of the most representative of the pollen of the species of the Poaceae family. The Phl p 5 allergen is responsible of 88.4% of allergic cases in Europe. Bet v1 is the major allergen and the most representative of the pollen of the Betula species. It Birch pollen provokes symptoms in 10-20% of allergic patients in North European countries. Alt a 1 is the major and the most representative allergen of the spores of the fungal genus Alternaria. At a world level, the incidence of the allergy to Alternaria spores varies between 4 and 40 % of the atopic patients. This study focuses on the detection and quantification on a daily basis, for the first time, of the allergens Phl p 5, Bet v 1 and Alt a 1 in Bellaterra (Barcelona) and Vitoria-Gasteiz, two localities in the North of Spain, for the years 2013-2015. It aims also to observe their correlation with the daily concentrations of corresponding pollen (Poaceae and Betula) and spores (Alternaria) types as well as with pollens presenting cross reactivity. The correlation with environmental factors is also undertaken, taking into consideration Temperature (maximum, minimum and mean), Precipitation, Relative Humidity and PM10. The sampling method used for allergen detection, multi-vial cyclone sampler, has proven to be efficient for pollen allergen sampling but not for sampling the allergens from fungal spores. To sample Alt a 1 a test was done with a High volume Total Particle Sampler (TPS). ELISA analyses was the method used to quantify Phl p 5 and Bet v 1. Alt a 1 could not be detected with this method with samples obtained with the cyclone sampler, but yes with those from the TPS sampler. Dot-Blotting was also tested with TPS samples to detect Alt a 1 and showed to be the most sensitive method for this allergen. The total allergen Phl p 5 and Bet v 1 measured per year varied from one year to another as well as from one location to another. The Annual Allergen Integral (sum of daily concentrations) in year 2015 were 10 times lower than in 2013 and 2014, respectively. Poaceae pollen was detected in days where no Phl p 5 was detected while Bet v 1 was detected in days where no Betula pollen was found. There was a positive significant correlation between daily concentrations of Phl p 5 and Poaceae pollen in Bellaterra (Barcelona), years 2013 and 2015. Also, a positive significant correlation was observed between daily concentrations of Bet v 1 and Betula pollen in Vitoria- Gasteiz, year 2015. But, no significant correlation was found between daily concentrations of Bet v 1 and Betula pollen in Bellaterra (Barcelona), years 2014 and 2015. To explain the presence of Bet v 1 in the atmosphere outside the main pollination season of Betula, a correlation between the allergen and the pollen concentrations of the cross-reactive genera Alnus, Castanea, Corylus and Quercus has been undertaken. A correlation was found for Quercus pollen and Bet v 1 daily values in Bellaterra (Barcelona), year 2015, but not in year 2014 neither in Vitoria-Gasteiz 2015. Phl p 5 and Bet v 1 daily concentrations did not show correlation with the meteorological parameters (Maximum, minimum and mean Temperature, Precipitation, Relative Humidity) but a positive correlation was found with the PM10 values from Montcada and the values in Bellaterra (Barcelona).

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Rowney, Francis. "Ecology and climates of early Middle Pleistocene interglacials in Britain." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/11836.

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This thesis refines and develops understanding of the ecological and climatic characteristics of early Middle Pleistocene (MIS 19-13, c. 780-430 ka) interglacial environments in Britain. This period is characterised by globally muted (i.e. low amplitude) glacial-interglacial cycles, which increased in amplitude c. 430 ka with the Mid-Brunhes Transition (MBT). However, the influence of these global climatic characteristics on climates and ecology at regional and local scales is yet to be fully understood. Local ecological processes, particularly disturbance processes, have also received limited attention in pre-Holocene interglacial settings, despite their likely importance for vegetation and habitat structure. Chapters 4, 5 and 6 present in-depth multi-proxy palaeoenvironmental studies from three early Middle Pleistocene sites: West Runton, Pakefield and Brooksby. A combination of Coleoptera, pollen, coprophilous fungal spores, microcharcoal and sedimentology is used to reconstruct local ecological attributes for each site. Multivariate analyses of these datasets indicate the importance of disturbance processes (herbivore activity, wildfire, hydrogeomorphic processes) in driving and maintaining local vegetation structure and habitat heterogeneity. This is explored further (in Chapter 8), emphasising the apparent importance of site-specific factors, rather than those shared between sites, in determining the relative influence of each disturbance factor. In Chapter 7, new approaches to the coleopteran Mutual Climatic Range (MCR) method are applied to a suite of coleopteran records from interglacial sites spanning the Middle and Late Pleistocene (c.712-126 ka, MIS 17-5e). Summer temperatures, winter temperatures and temperature seasonality are reconstructed, to test whether there is evidence for MBT expression in Northwest European thermoclimates. No evidence for this is found, and it is suggested (in Chapter 8) that MBT expression in this region may instead be reflected in hydroclimatic variables (e.g. enhanced annual precipitation). Finally, it is suggested that disturbance processes and potentially wetter climates were beneficial to contemporary Lower Palaeolithic populations in Northwest Europe.

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Dillon, Candace. "Assessment of pre-PCR whole genome amplification of single pollen grains using flowering dogwood (Cornus florida)." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1865.

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Studies of gene flow in natural plant populations often focus on either historical or abiotic dispersal methods (e.g. wind, water, gravity), but there is little information available on contemporary, animal-mediated pollen dispersal patterns. Emerging molecular laboratory techniques allow unprecedented insights into spatial patterns of pollen-mediated gene flow. However, to date, technical challenges have limited their widespread application. The genome of a pollen grain can be amplified via whole genome amplification (WGA) prior to traditional amplification via polymerase chain reaction (PCR) to prevent the stochastic effects associated with low copy number amplification. Even still, WGA can suffer from low success rates or poor repeatability. The present study examined the extent to which WGA can be used to aid in understanding insect-mediated pollen flow in Cornus florida (flowering dogwood) within Virginia Commonwealth University’s Inger and Walter Rice Center for Environmental Life Sciences. Initial amplification of DNA isolated from frozen grains was successful, until the pollen had been stored longer than 120 days at -20ºC. After this time point, the PCR targets failed to amplify. The percent success of downstream PCR amplification on fresh pollen grains varied from 20% to 100%, with an average of 62% success. The addition of a common molecular crowder, polyethylene glycol, produced consistent amplification, regardless of input DNA concentration and eliminated the need for triplicate samples. Successful pollination and subsequent reproduction of flowering plants has a substantial ecological and agricultural importance that warrants increased understanding into how insects move pollen across the landscape. Determining the haploid profiles of a single pollen grain will allow scientists to elucidate dispersal patterns of pollen grains and track the movement and efficiency of biotic pollinators.

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Hugg, T. (Timo). "Exposure to environmental tobacco smoke, animals and pollen grains as determinants of atopic diseases and respiratory infections." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514291968.

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Abstract Little is known about a) the differences in allergic and respiratory diseases between the Finnish and Russian populations, and the environmental factors associated with those differences, and b) exposure to pollen grains indoors and the efficiency of penetration of pollen from outdoor to indoor air. This thesis is based on a cross-sectional population-based epidemiological study conducted in Imatra (Finland) and Svetogorsk (Russia) in 2003 and a rotorod-type-sampler-based pollen study conducted in the province of South Karelia (Finland) between 2003 and 2004. The prevalence of allergic diseases was higher among Finnish than Russian schoolchildren. The symptoms among allergic children were more severe, and the occurrence of respiratory infections was in general more frequent in Russia than in Finland. In the logistic regression analyses the risk of asthma was particularly related to high maternal smoking exposure, and the risk of the common cold was related to high combined parental smoking during infancy (adjusted OR 1.83, 95% CI 1.06–3.17) in Finnish children. Among Russian children, allergic conjunctivitis was related to maternal smoking, while the common cold was inversely related to paternal and parental smoking (0.60, 0.37–0.98 and 0.31, 0.11–0.83, respectively) during the study period. The risk of asthma was inversely related to any indoor dog-keeping in Finland (0.35, 0.13–0.95), whereas in Russia the risk of asthma was increased in relation to combined indoor cat exposure during infancy and the study period (4.56, 1.10–18.91). The concentrations of pollen grains decreased from abundant (0–855 pollen grains per cubic meter, pg/m3) to low (0–3 pg/m3), when moving from outdoors to indoors and further. The differences in diseases and symptoms in these two closely related populations could be ascribed to differences in culture, exposures, diagnostic criteria and treatment. The concentrations of pollen in indoor air during the flowering period were mostly on a level high enough to cause reactions in only the most sensitive subjects. The results suggest that more efforts should be directed to reducing parental smoking, to studying the role and effects of nationally different animal exposures in childhood, and to assessing the importance of different penetration routes of pollen grains
Tiivistelmä Suomen ja Venäjän välisistä allergioiden ja hengitystietulehdusten esiintymiseroista ja esiintymiseen vaikuttavista ympäristötekijöistä tiedetään varsin vähän. Myös tutkimuksia siitepölyille altistumisesta sisätiloissa ja siitepölyjen tunkeutumiskyvystä ulkoilmasta sisäilmaan on niukasti. Tutkimus yhdistää sekä lääketieteellisen että luonnontieteellisen tutkimusalan tutkimustraditiot sekä atooppisten sairauksien ja/tai hengitystietulehdusten tärkeimpien määrittäjien tarkastelun yhdeksi tutkimuskokonaisuudeksi. Väestö- ja kyselylomakepohjainen poikkileikkaustutkimus toteutettiin Suomen ja Venäjän rajan molemmin puolin sijaitsevissa Imatran ja Svetogorskin kaupungeissa vuonna 2003. Tutkimusväestö koostui 512 suomalaisesta ja 581 venäläisestä 7–16-vuotiaasta koululaisesta (osallistumisaste 79 %). Rotorod-tyyppisen keräimen käyttöön perustuva siitepölytutkimus toteutettiin erilaisissa ulko- ja sisätiloissa Lappeenrannan ja Imatran kaupungeissa, Rautjärven kunnassa ja valtatie 6:lla vuosina 2003 ja 2004. Atooppisten sairauksien esiintyvyys oli runsaampaa suomalaisten koululaisten keskuudessa. Sitä vastoin allergisten lasten kokemat oireet olivat voimakkaampia ja hengitystietulehdusten esiintyvyys oli runsaampaa venäläisten koululaisten keskuudessa. Astmariski kytkeytyi erityisesti äidin runsaalle tupakoinnille altistumiseen raskauden (vakioitu OR 3.51, 95 % luottamusväli 1.00–12.3), ensimmäisen elinvuoden (3.34, 1.23–9.07) ja tutkimuksen aikana (3.27, 1.26–8.48). Nuhakuumeen riski oli suurentunut suomalaisten koululaisten keskuudessa, jotka olivat altistuneet molempien vanhempien runsaalle tupakoinnille ensimmäisen elinvuoden aikana (1.83, 1.06–3.17). Äidin tupakoinnille ensimmäisen elinvuoden (4.53, 1.49–13.8) ja tutkimuksen aikana (2.82, 1.07–7.44) altistuneilla venäläisillä oli suurentunut allergisen silmän sidekalvotulehduksen riski. Tutkimuksen aikainen isän ja vanhempien tupakointi vähensi nuhakuumeen riskiä (0.60, 0.37–0.98; 0.31, 0.11–0.83) Venäjällä. Suomessa koiranpito sisätiloissa vähensi astmariskiä (0.35, 0.13–0.95), vastaavasti Venäjällä raskauden jälkeinen sisätiloissa tapahtuva kissa-altistus lisäsi koululaisten astmariskiä (4.56, 1.10–18.91). Siitepölyjen pitoisuudet pienenivät siirryttäessä ulkoa (0–855 siitepölyhiukkasta ilmakuutiossa; sp/m3) sisätiloihin (0–17 sp/m3). Ympäristöaltisteisiin ja sairauden ennusteeseen vaikuttavat sekä kansallinen kulttuuri ja vakiintuneet tavat, että erot diagnosointikriteereissä, yleisessä tautitietoisuudessa ja lääkkeiden saatavuudessa. Näin ollen altisteiden voimakkuus ja kesto sekä terveysvaikutukset voivat vaihdella merkittävästi lähellä toisiaan sijaitsevien alueiden välillä. Siitepölypitoisuudet sisätiloissa olivat pääosin tasolla, jolle altistuminen aiheuttaa oireita vain kaikkein herkimmille allergisille. Tutkimuksen tulosten mukaan lisää voimavaroja tulisi suunnata passiiviselle tupakoinnille altistumisen vähentämiseen erityisesti yksilökehityksellisesti herkkien varhaisvaiheiden aikana, kansallisten eläinaltistuserojen terveysvaikutusten selvittämiseen sekä siitepölyjen erilaisten kulkeutumisreittien merkityksen tutkimiseen

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Aziz, Ahmad Naseer. "Genetic analysis of the anther-derived progeny and isolated pollen grains of a culture-responsive Solanum clone." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0023/NQ38342.pdf.

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Rakotomanga-Rasolonjatovo, Vololonirina. "Incidences des traitements pesticides sur les grains de pollen de Tradescantia et de l'orge : Aspects cellulaires et moléculaires." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT019A.

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L'incidence des pesticides sur la qualite pollinique et sur le metabolisme fondamental du gametophyte male en formation a ete etudiee chez le tradescantia bracteata l. Et chez l'hordeum vulgare l. Les pesticides affectent la qualite pollinique et les alterations induites dans les grains de pollen sont dose-dependantes. Le nombre de grains de pollen qui germent diminue et l'elongation du tube pollinique est ralentie. La viabilite pollinique a ete reduite chez le tradescantia lors des traitements par contact direct ou par voie vasculaire. Dans le cas de l'orge seuls les traitements repetitifs affectent le taux de pollen viable. Les noyaux des cellules polliniques et des cellules tapetales constituent une cible pour l'action des pesticides. En effet, la morphologie de la chromatine, la teneur en adn ainsi que la synthese d'adn du pollen ont ete modifiees. Par ailleurs, chez le tradescantia traite par l'herbicide, la teneur en adn des cellules tapetales a ete egalement reduite. Les pesticides ont modifie un nombre limite de proteines polliniques et tapetales, les changements des profils proteiques pouvant se resumer par l'induction ou l'inhibition de la synthese des proteines et par l'accumulation ou de la degradation des proteines pre existantes. Les traitements pesticides ont induit chez les deux plantes la synthese d'un polypeptide de 25/26 kda dans les grains de pollen et celle d'un polypeptide de 32 kda dans les microsporocytes. De plus des proteines specifiques du stade et du traitement apparaissent et/ou disparaissent. Chez l'orge, la synthese d'un polypeptide de 18 kda a ete induite a tous les stades de developpement et quel que soit le traitement. Chez le tradescantia, l'apparition d'une proteine de 62 kda dans le tapis a ete reliee au traitement a l'herbicide. Chez les deux especes, la comparaison des sequences des proteines accumulees avec celles des banques de donnees a permis d'identifier en particulier une proteine ayant une homologie de sequence avec les histones h3. 3 d'arabidopsis thaliana

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Rowell, Louise. "Palynomorph retention on clothing under differing conditions." University of Western Australia. Centre for Forensic Science, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0165.

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[Truncated abstract] Palynology has been used in a number of criminal cases where pollen and spores (palynomorphs) on clothing has featured as evidence. Pollen and spores are microscopic, generally morphologically unique to a plant genus and often species, resistant to decay, produced in large amounts and are components of soil. These unique features of pollen and spores make palynology a highly valuable forensic tool. Clothing is an excellent collector of pollen and spores as they become trapped in the fabric weave when clothing is brushed against flowering plants, comes into contact with dust, soil or air-borne pollen. Most forensic palynologists have found that palynomorphs from a crime scene may remain on clothing after washing or several days wear. No empirical research has been conducted on the retention of palynomorphs on clothing under differing conditions. Research of this kind is required to provide support for the future presentation and validation of palynological evidence in court. This project examined the relative retention of palynomorphs on clothing that had been worn during a simulated assault in a sheltered garden on the grounds of St George's College, Western Australia. Three replicate control soil samples each were collected from the actual assault scene and the whole garden to provide a baseline palynological profile for comparison to the experimental (Evidentiary) clothing samples. Forty pollen samples from the predominant species of plants in the garden and surrounds were collected, processed and databased as a reference for palynomorph identification. Standard T-shirts and jeans were chosen as the research clothing. During the simulated assault the knees of the jeans and the backs of the T-shirts came into abrasive contact with the soil of the garden for approximately one minute. The clothing then underwent three 'conditions' to simulate 'real life' situations. Three clothing sets were immediately collected after the assault (E1), three sets were worn for a period of three days after the assault (E2) and three sets were washed after the assault (E3). ... The Background clothing samples did not have a profile similar to the research garden but the profiles collected from each set reflected the areas to which they were worn. The number of palynomorphs per gram of garden soil ranged from thousands to tens-of-thousands of palynomorphs. The total number of palynomorphs collected by the E1 samples ranged from 100,000 to millions per clothing item. The E2 samples retained 1000's to tens-of-thousands of palynomorphs and the E3 samples retained 100's to 1000's of palynomorphs. The background clothing samples collected 1000's to tens-of-thousands of palynomorphs. These results confirm that jeans and T-shirts worn during an assault then worn for a period of days, or washed, will still contain pollen and spores characteristic of the assault area. This highlights the importance of investigating police enquiring where and for how long clothing of interest has been worn before and after an event, or if the clothing has been washed since the event. The results of this study will provide forensic palynologists with supportive data for future casework involving clothing.

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BULANT-ROBERT, CHRISTINE. "Contribution a l'etude de l'effet du pollen sur le developpement des grains de mais (zea mays l. ). Consequences agronomiques." Paris 11, 1996. http://www.theses.fr/1996PA112282.

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Notre travail a consiste a etudier le phenomene de xenie sur le developpement des grains de mais. Pendant 3 annees, des croisements entre 20 lignees males et 6 lignees femelles ont ete effectues en realisant des melanges d'autopollen et d'allopollen. Quelle que soit l'annee, il y a un avantage de l'allofecondation de 12%. A cote du fort effet femelle attendu, il est apparu des differences entre les males etudies. Quand la femelle est un hybride simple, l'avantage de l'allofecondation est plus faible (4%). Cela suggere que lorsque les ressources sont moins limitantes, l'ecart entre les grains issus de croisement et ceux issus d'autofecondation tend a disparaitre. L'effet de l'allofecondation est exprime a la fois sur les embryons (2n) et sur les albumens (3n). Par contre, les croisements reciproques ne sont pas equivalents. L'ensemble des resultats montre que les genes paternels, a cote des genes maternels, ont un role dans le transfert des assimilats et dans l'elaboration des reserves dans le grain des les premiers stades apres la fecondation. L'etude d'activites enzymatiques (adpgppase, teneurs en saccharose, glucose et amidon) dans le grain montre que l'effet de l'allofecondation semblent lie a un meilleur metabolisme de l'amidon. L'avantage de l'allofecondation persiste apres la germination des plantules mais les differences entre les croisements reciproques disparaissent. Une correlation existe entre les caracteres mesures au stade grain (masse des grains, avantage de l'allofecondation) et les rendements et la surface foliaire mesures au stade adulte. La xenie et l'heterosis semblent s'exprimer sur les memes bases genetiques. L'utilisation agronomique de la xenie par la culture en melange de varietes hybrides simples semblent permettre une augmentation de la masse due a l'allofecondation et du nombre de grains par epi due a la presence de plusieurs sources de pollen. Les conditions d'utilisations des melanges sont discutees

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Marret-Davies, Fabienne. "Evolution paléoclimatique et paléohydrologique de l'Atlantique est-équatorial et du proche continent au Quaternaire terminal : contribution palynologique, kystes de dinoflagelles, pollen et spores." Bordeaux 1, 1994. http://www.theses.fr/1994BOR10512.

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L'analyse des palynomorphes marins (dinokystes) et continentaux (pollen et spores) dans les sediments marins superficiels et anciens (deux carottes marines prelevees a 121s-1157w et 212s-56e) a permis de mettre en evidence au cours de ces derniers 140000 ans b. P. La variabilite spatiale, temporelle et d'intensite de l'upwelling oceanique et de la productivite primaire associee en phase avec la variabilite de la circulation atmospherique ainsi que celles des temperatures superficielles des masses d'eaux. La variabilite thermique des eaux superficielles a ete reliee aux conditions climatiques des hautes latitudes australes et au forcage precessionel. L'etablissement d'un deficit pluviometrique et thermique sur la bordure continentale du golfe de guinee au cours des phases glaciaires a egalement ete observe, la situation etant inverse au cours des phases interglaciaires

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Olaniyan, Toyib Adedamola. "A prospective cohort study on ambient air pollution, airborne pollen (and fungal spores) and respiratory morbidities including childhood asthma in adolescents from the Western Cape Province." Doctoral thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29598.

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Background: The epidemiological studies investigating environmental risk factors associated with asthma among children living in informal settlements are scant as are studies on the independent and co-pollutant effect of short- and long-term exposures to ambient air pollutants as well as fungal spores on asthma-associated outcomes. This study systematically investigated these factors among schoolchildren residing in informal settlements in the Western Cape province of South Africa. Methods: A cohort study of grade-4 schoolchildren (n=590) recruited from six primary schools in four informal settlements was conducted over 12 months. In addition, a panel study, investigated the children for 2 consecutive school weeks in both summer and winter. Spirometry and fractional-exhaled nitric oxide (FeNO) measurements were conducted during the school day, while the International Study on Asthma and Allergy in Children (ISAAC) standardised questionnaire was administered to the parent or guardian at the child’s home at baseline and follow-up. The presence of atopy was determined based on a positive Phadiatop test on sera. In the cohort study, annual NO2 and PM2.5 levels were computed for each child’s address using a land-use regression model. Daily PM10 levels obtained from a stationary monitor near two of the study areas were used for the panel study. Airborne pollen and fungal spore measurements were obtained directly from a stationary monitor placed in each study area. Results: The prevalence of doctor-diagnosed asthma was 3.4% and only half of them were on asthma treatment. The prevalence of wheezing in the past 12 months (12.9%), airway obstruction (17.6%) and airway inflammation (10.2%) was much higher. The presence of damp conditions, visible mould growth, passive smoking as well as paraffin-use for cooking and heating were significant indoor risk factors for asthma. The estimated annual average NO2 level of 16.6 µg/m3 was below the WHO annual exposure standards, however more than a third of children were exposed to annual PM2.5 levels above the 10 µg/m3 WHO standard and the allergic symptom threshold level of 100 spores/m3 for Alternaria spores. In the panel study, daily exposure of schoolchildren to Alternaria and Cladosporium spores independently decreased FEV1 (-27.56 ml, 95% CI: -50.60 to -4.51 ml per 10 spores/m3 increase in Alternaria; and -86.19ml, 95% CI: -131.69 to -40.70 ml per 50 spores/m3 increase in Cladosporium respectively) from lag day-0 to lag day-5, especially in the winter monitoring period. In the cohort study, an interquartile range increase of 14.2 µg/m3 in annual NO2 was associated with an risk of new onset ocular-nasal symptoms (adjusted odds ratio – aOR: 1.63, 95% CI: 1.01 – 2.60), wheezing (aOR: 3.57, 95% CI: 1.18 – 10.92), more than two or more asthma symptom score (aOR: 1.71, 95% CI: 1.02 – 2.86), and airway inflammation defined as FeNO > 35ppb (aOR: 3.10, 95% CI: 1.10 – 8.71), independent of PM2.5 exposures. In addition, an interquartile increase of 83.1 spores/m3 in 24-hour annual Alternaria spore levels was associated with an increased risk of airway inflammation incidence and having a ≥ 10% increase in FeNO at follow-up both in the single-pollutant model and two-pollutant model. Conclusion: This study demonstrated a large proportion of undiagnosed and untreated asthma in schoolchildren living in informal settlements, with both indoor and outdoor mould exposures playing an important role in addition to ambient chemical pollutants. The incidence of new onset asthma symptoms and airway inflammation associated with NO2 at levels below the WHO Air Quality Standards raises the issue of the adequacy of these standards in protecting respiratory health. Raised long-term levels of airborne Alternaria spores contributing to increased airway inflammation is likely to form the basis for the increased risk of acute symptoms and airway effects observed in association with exposure peaks.

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Bélanger, Sébastien. "Caractérisation génomique et transcriptomique de la microspore embryogénique chez l'orge." Doctoral thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/33304.

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L’androgenèse est une biotechnologie végétale utilisée pour fixer le bagage génétique des plantes en une seule génération. Elle repose sur la capacité d’un grain de pollen immature, la microspore, à restaurer sa totipotence cellulaire végétale et se dédifférencier puis s’engager dans la voie de l’embryogenèse. Or, on observe que la capacité de la microspore à s’engager dans l’embryogenèse est génétiquement variable. En dépit des nombreux avantages qu’elle présente, l’androgenèse entraîne souvent une conséquence indésirable, soit une distorsion de la ségrégation (DS) chez les populations issues de cette biotechnologie. Ma thèse porte sur l’étude (i) du transcriptome de la microspore en transition entre la voie de développement du grain de pollen et celle de l’androgenèse et (ii) de la DS pour déterminer quand la DS survient dans le processus et où elle affecte le génome. J’ai utilisé l’orge comme espèce modèle pour mon étude. L’analyse transcriptomique a été réalisée sur la microspore isolée de l’anthère à trois stades, soit avant (jour 0) et immédiatement après (jours 2 et 5) l'application d'un traitement de stress visant à induire la voie de l’androgenèse. Je me suis intéressé à deux catégories de gènes; soit les gènes exprimés exclusivement à un stade précis et les gènes exprimés différemment lors de l’initiation de l’androgenèse. J’ai pu identifier des gènes exprimés exclusivement dans la microspore au jour 0 (11), 2 (34) ou 5 (367). Au jour 5, j’ai constaté l’induction de nombreux gènes codant pour des FT et des gènes impliqués dans la synthèse ou la transduction du signal de nombreux régulateurs de croissance. L’analyse des gènes exprimés différemment m’a permis d’identifier certains processus métaboliques qui sont activés/réprimés lors du passage de la microspore du jour 0 au jour 2 et du jour 2 au jour 5. Les gènes exprimés exclusivement à un stade précis du développement pourraient servir de marqueurs moléculaires indicateurs de la performance en androgenèse pour optimiser les protocoles de culture. Ensuite, la DS a été étudiée par une approche de génotypage à l’échelle génomique. J’ai d’abord développé une méthodologie d’analyse génotypique novatrice, reproductible et précise pour étudier la fréquence allélique sur un échantillon en composite. Cette méthode m’a permis d’étudier la fréquence allélique chez 1) des échantillons de microspores (avant et après l’application d’un stress), 2) des embryons et 3) des plantes régénérées. J’ai montré que la DS survenait à la fois lors du développement des embryons et la régénération des plantes. Aucune DS n’a été observée chez les échantillons de microspores. Mes résultats montrent que la sélection engendrant la DS s’opère au cours de la culture in vitro. Toujours à l’aide de cette méthode de génotypage en composite, j’ai identifié et comparé la fréquence et l’étendue de la DS chez 12 populations de lignées haploïdes doublées (HD). Dans cette seule étude, un plus grand nombre de populations de lignées HD (12) ont été caractérisées que ce qui avait été fait dans la somme de toutes les études antérieures dans la littérature scientifique. Nous avons montré que les régions de distorsion de ségrégation différaient beaucoup quant à leur position, leur étendue et l’amplitude de la distorsion d’un croisement à l’autre. La connaissance de ces allèles permettrait de prédire le potentiel androgénique des génotypes dans un programme de sélection. Mes travaux de thèse élèvent à l’ère des «omics» la recherche chez la microspore d’orge dans le système de l’androgenèse. À une échelle sans précédent, mon étude transcriptomique explore et décrit les changements d’expression génique au cours de la transition développementale de la microspore. Mon étude génomique identifie quand s’exerce la sélection engendrant la distorsion de la ségrégation des allèles dans ce système et décrit quelles régions chromosomiques sont affectées par cette distorsion. À la lumière de mes résultats, dans le dernier chapitre, je propose certaines pistes de recherche pour poursuivre l’étude des mécanismes moléculaires dirigeant la transition développementale de la microspore en androgenèse et pour développer des outils de génotypage afin d’utiliser la DS comme un outil d’amélioration génétique.
Androgenesis is a plant biotechnology used to fix the genetic background of plants in a single generation. This is based on the ability of an immature pollen grain, the microspore, to restore its totipotency, to dedifferentiate and then to engage in the path of embryogenesis. However, it is observed that the ability of the microspore to engage in embryogenesis is genetically variable. Despite the many desirable attributes of androgenesis, an undesirable side - effect is the segregation distortion (SD) encountered in populations resulting from this biotechnology. My thesis focuses on (i) the study of the transcriptome of microspores undergoing a developmental transition from the pollen - grain pathway towards embryogenesis and (ii) to identify when SD arises in the process and in which genomic regions it occurs. I used barley as a model species for my studies. Transcriptomic analysis was performed on microspores isolated from anthers at three stages corresponding to the microspore before (day 0) and immediately after (days 2 and 5) the application of a stress treatment aimed at inducing embryogenesis. I was interested in two categories of genes: those expressed exclusively at a specific stage of microspore development and those that were differentially expressed during the initiation of androgenesis. I was able to identify genes expressed exclusively in the microspore on day 0 (11), 2 (34) or 5 (367). On day 5, I found the induction of many genes encoding transcription factors (T Fs) in addition to genes involved in the synthesis or signal transduction of many growth regulators. The analysis of differentially expressed genes allowed me to identify certain metabolic processes that were activated/repressed during microspore development from day 0 to 2 and from day 2 to 5. Genes expressed exclusively at a specific stage of development could serve as molecular markers indicative of the performance in androgenesis to optimize isolated microspore culture protocols. Then, SD was studied using a whole - genome genotyping approach. I first developed an innovative, reproducible and accurate genotypic analysis methodology to determine allelic frequency on pooled samples. This method was then used to estimate allelic frequencies in samples of microspores (before and after the application of stress), embryos and regenerated plants. I showed that SD arises during both the development of embryos and the regeneration of plants. No SD was observed in samples of microspores. My results show that the selective forces promoting SD act during in vitro culture. Still using the same genotyping method performed on pooled samples, I identified and compared the frequency and extent of SD in 12 populations of doubled haploid lines (DH). A greater number of DH (12) populations were characterized in my study alone than the sum of all previous studies in barley. I showed that segregation distortion regions greatly differ in their position, extent, and magnitude in different DH populations. Knowledge of these alleles would be useful to predict the androgenic potential of a genotype in a breeding program. My dissertation has allowed research into barley microspores, or more widely androgenesis, to enter into the “omics” era. On an unprecedented scale, my transcriptomic study explores and describes the gene expression changes that occur during the developmental transition that the microspore undergoes in the course of androgenesis. My genomic study identifies when the selection (producing SD) arises in this system and describes which chromosomal regions are affected by this distortion. In light of my findings, in the final chapter I propose some lines of research to further study the molecular mechanisms driving the developmental transition from microspores to embryos and to develop genotyping tools to use SD as a genetic improvement tool.

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Radaeski, Jefferson Nune. "Morfologia polínica de táxons de Poaceae do rio grande do sul: uma abordagem para distinguir vegetações campestres e florestais no sul do Brasil." reponame:Repositório Institucional da UNIPAMPA, 2015. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/548.

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Submitted by Francine Silva (francine.silva@unipampa.edu.br) on 2016-09-27T12:42:09Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Morfologia Polínica de Táxons de Poaceae do Rio Grande do Sul Uma abordagem para distinguir vegetações campestres e florestais no Sul do Brasil.pdf: 1427510 bytes, checksum: d3bfb6022f41971b6b785d86f5c494af (MD5)
Made available in DSpace on 2016-09-27T12:42:09Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Morfologia Polínica de Táxons de Poaceae do Rio Grande do Sul Uma abordagem para distinguir vegetações campestres e florestais no Sul do Brasil.pdf: 1427510 bytes, checksum: d3bfb6022f41971b6b785d86f5c494af (MD5) Previous issue date: 2015-07-16
Grãos de pólen de Poaceae identificados em registros quaternários podem ser somente indicativos da vegetação de Campo e não permite a obtenção de maiores inferências ambientais e ecológicas devido à uniformidade dos grãos de pólen. Neste sentido, foram realizadas análises em microscopia óptica e eletrônica de varredura em diferentes táxons contemplando-se todas as tribos e subfamílias de Poaceae do Rio Grande do Sul para avaliar se seus grãos de pólen podem ser distinguidos em relação: (i) ao tipo de vegetação (Campo e Floresta), (ii) ao metabolismo fotossintético C3 e C4, (iii) ao tipo de hábito entre as espécies florestais, (iv) a diferentes níveis taxonômicos (gênero, tribo, ubfamília). São apresentadas informações polínicas sobre 68 espécies de Poaceae istribuídas em vegetações campestres ou florestais do Rio Grande do Sul. A análise por microscopia óptica e eletrônica de varredura permitiu distinguir os grãos de pólen em relação ao tipo de vegetação em que os táxons estão distribuídos (Campo e Floresta). Grãos de pólen de espécies florestais apresentaram tamanho maior do que táxons campestres, assim como espécies com metabolismo fotossintético C3 demonstraram tendência a apresentar grãos de pólen maiores que táxons com metabolismo C4. Padrões nos tamanhos dos grãos de pólen de táxons florestais de acordo com o hábito também foram obtidos, destacando-se o tamanho distinto dos grãos de pólen da tribo Bambuseae. Com base nos resultados, os grãos de pólen de Poaceae podem ser utilizados como indicadores ambientais para melhor caracterização das dinâmicas e reconstituições vegetacionais no sul do Brasil.
Poaceae pollen grains identified in quaternary records can only indicate the grassland vegetation and does not allow more environmental and ecology inferences due to the uniform morphology of the pollen grains. In this sence, analyses were performed in optical and scanning electron microscopy in different taxa representing all tribes and subfamilies of Poaceae family of the Rio Grande do Sul to assess whether their pollen grains can be distinguished in relation: (i) to the type of vegetation (grassland and forest), (ii) to the photosynthetic metabolism C3 and C4, (iii) to the type of habit between forest species, (iv) to different taxonomic levels (genera, tribe, subfamily). Are presented pollen information about 68 species of Poaceae family distributed in the grassland or forest vegetation of the Rio Grande do Sul. Analysis by optical and scanning electron microscopy allowed to distinguish the pollen grains in relation to the type of vegetation of species (grassland and forest). Pollen grains of forest species showed larger size than grasslands taxa, as well as species with photosynthetic metabolism C3 showed trend to have pollen grains larger than taxa with metabolism C4. Patterns in sizes of pollen grains of the forest species in relation to the habit were also obtained, highlighting the distintic size of pollen grains of the ambuseae tribe. Based on the results, the Poaceae pollen grains can be used as environmental indicators for better characterization of the dynamics and reconstructions vegetation in southern Brazil.

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Belonsi, Talita Kely. "Palinotaxonomia em espécies brasileiras de Beslerieae Bartl e Napeantheae Wiehler (Gesneriaceae) - caracteres evolutivos e influência fitogeográfica." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/59/59139/tde-03122018-121202/.

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Foram estudadas a morfologia polínica de 20 espécies de Beslerieae Bartl. (Anetanthus, Besleria e Tylopsacas) e quatro espécies de Napeantheae Wiehler (Napeanthus), nativas no território brasileiro e encontradas principalmente nos biomas da Amazônia e/ou Mata Atlântica. O objetivo deste trabalho é contribuir com a caracterização morfológica das espécies, identificando dados polínicos que possam auxiliar na taxonomia do grupo, ampliando desta forma os conhecimentos sobre a diversidade polínica nos gêneros estudados e fornecendo subsídios para o melhor entendimento das relações entre as tribos brasileiras de Gesneriaceae e da evolução dos caracteres polínicos nestes gêneros. Também foi discutida a relação entre a morfologia polínica de Besleria e sua distribuição fitogeográfica. O material analisado foi obtido a partir de espécimes depositados nos herbários INPA, SP e MBM. Os grãos de pólen foram acetolisados, medidos, fotografados em microscopia óptica, microscopia eletrônica de varredura e transmissão e descritos qualitativamente. Os dados quantitativos foram analisados por meio de estatísticas descritiva e multivariada. Os grãos de pólen são mônades; isopolares; de tamanho pequeno; com grande variação de forma, podendo ser, oblatos, suboblatos, oblatos-esferoidais, prolatos-esferoidais, subprolatos ou prolatos; âmbitos circulares, circulares-lobados, subcirculares a subtriangulares. As aberturas são 3-colpadas, 3- (4) colpadas ou 3-colporadas; colpos longos, curtos ou muito curtos; estreitos a largos; extremidades afiladas ou arredondadas, algumas vezes possuindo margem, colpo constrito ou membrana ornamentada; endoabertura predominantemente lolongada, as vezes circulares. Ornamentação da exina fossulada, microrreticulada, microrreticulada-rugulada, microrreticulada-fossulada, rugulada, rugulada-perfurada. Exina variando de muito fina, fina a espessa, sexina sempre mais espessa que a nexina. Variações no tipo de abertura e nos padrões da ornamentação da exina dos grãos de pólen contribuíram para a distinção das espécies estudadas e confirmam o caráter euripolínico de Beslerieae e Napeantheae.
The pollen morphology of 24 Brazilian species of Beslerieae Bartl. (Anetanthus, Besleria and Tylopsacas) and Napeantheae Wiehler (Napeanthus) was studied, these species are native to the Amazon and / or Atlantic Forest biomes. The objective of this study is to contribute to the morphological characterization of the species, identifying pollen data that may help in the taxonomy of the group, thus increasing the knowledge about the pollen diversity and evolution in the studied genera and providing subsidies for a better understanding of the relations between the Brazilian tribes of Gesneriaceae. Also we discussed the relationship between the pollen morphology of Besleria and its phytogeographic distribution. The material analyzed was obtained from specimens deposited in the INPA, SP and MBM herbaria. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. Quantitative data were analyzed using descriptive and multivariate statistics. The pollen grains are monads; isopolar; small size; with variation in shape, oblate, suboblate, oblate-spheroidal, prolate-spheroidal, subprolate or prolate; circular, circular-lobed, subcircular to subtriangular amb. The apertures are 3-colpate, 3-(4) colpate or 3-colporate; long, short or very short colpi and narrow to wide; with or without margo, rounded or tapered at the polar ends, sometimes constricted or with ornate membrane; endoapertures lolongate or circular. Exine fossulate, microrreticulate, microreticulate-rugulate, microreticulate-fossulate, rugulate, rugulate-perforate. Very thin, thin to thick exine, sexine always thicker than nexin. Variations in the type of aperture and patterns of exine ornamentation of the pollen grains contributed to the distinction of the species studied and confirmed the eurypalynous character of Beslerieae and Napeantheae.

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Santos, Tha?la Vieira Alves dos. "Estudos micromorfol?gicos em Portulaca L. (Portulacaceae) do Brasil." Universidade Estadual de Feira de Santana, 2016. http://localhost:8080/tede/handle/tede/395.

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Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-09-26T21:20:40Z No. of bitstreams: 1 THA?LA VIEIRA ALVES DOS SANTOS_v_final_ficha-2.pdf: 5538347 bytes, checksum: f6306a15edb73efd871da71bcbbdd53c (MD5)
Made available in DSpace on 2016-09-26T21:20:40Z (GMT). No. of bitstreams: 1 THA?LA VIEIRA ALVES DOS SANTOS_v_final_ficha-2.pdf: 5538347 bytes, checksum: f6306a15edb73efd871da71bcbbdd53c (MD5) Previous issue date: 2016-03-29
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Portulaca hirsutissima is a succulent herb that occurs in open fields, sandy or rocky soil in distinct regions in Brazil, belonging to the Portulacaceae family. We analyzed the external morphology, seeds and pollen grains in representatives of this species and related morphotypes along their known distribution. We observed a consistent variation in their micromorphology and two new species are here described and illustrated. Portulaca giuliettiae occurs in Eastern Brazil, from Paraiba to Rio de Janeiro and P. goiasensis is restricted to the Chapada dos Veadeiros, in Central Brazil, while P. hirsutissima is now considered as restricted to Minas Gerais State.
Portulacaceae ? uma fam?lia com ca. de 100 esp?cies de ervas suculentas, com distribui??o em todo o mundo, tendo como centro de diversidade as Am?ricas. O grupo apresenta taxonomia complexa, com caracteres macromorfol?gicos vari?veis e muitas vezes de dif?cil interpreta??o. Neste trabalho foram analisados caracteres micromorfol?gicos das esp?cies que ocorrem no Brasil, como a ornamenta??o das sementes e morfologia pol?nica, em busca de melhor compreender os limites taxon?micos entre as esp?cies. As varia??es observadas envolveram a presen?a de poros ou colpos distribu?dos em todo gr?o de p?len, permitindo a identifica??o de tr?s tipos pol?nicos: pantossincolpado, com colpos organizados em pent?gonos; pantossincolpado, com colpos organizados em espiral; e pantoporado, com poros isolados e organizados em poliedros. A ornamenta??o das sementes forneceu os caracteres taxon?micos mais importantes e permitiu a separa??o de todas as esp?cies analisadas, apoiando inclusive a recente proposi??o de duas novas esp?cies end?micas do Brasil, relacionadas a P. hirsutissima e tamb?m distintas pela morfologia pol?nica.

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Li, Jie. "Reconstruction de la végétation et du climat durant le Quaternaire récent à partir de deux tourbières en zone subtropicale en Chine." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20266/document.

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La chine subtropicale est considérée comme une zone riche en biodiversité ainsi qu'une réserve naturelle abritant plusieurs espèces de plantes endémiques sous l'influence de la Mousson Asiatique (MA). Les enregistrements paléoclimatiques continus dans cette région sont trop peu nombreux pour comprendre l'évolution floristique liée aux changements climatiques qui demeure ainsi méconnue, particulièrement durant le DMG. Dans ce contexte, ce travail a pour objectifs d'étudier, au cours des derniers 40000 ans, la variabilité floristique et climatique enregistrées dans les zones humides montagneuse sub-tropicales chinoises. Notre étude s'appuie sur l'étude de deux carottes sédimentaires ou la variabilité est reconstituée à partir de l'étude palynologique. L'enregistrement le plus long (derniers 42000 ans) a été obtenu sur une carotte prélevée dans la zone humide sub-alpine de Dajiuhu, dans les montagnes Shennongjia situées en Chine centrale. Cette région est fortement influencée par la Mousson Est Asiatique (MEA) et caractérisée par des forets tempérées décidues associées à quelques taxons de conifères. L'autre enregistrement concerne une carotte (GT-2), qui quant à elle enregistre les derniers 21000 ans, prélevée dans la zone humide de Gutian, province de Guangxi au sud de la chine sous l'influence de la mousson indienne (MI). L'objectif de ce travail est de reconstituer les variations régionales de la végétation et les variations climatiques liées aux deux systèmes de mousson (MEA et MI). L'étude palynologique de nos deux carottes est complétée et renforcée par une approche multi-proxy s'appuyant sur les spores, le δ13C, l'analyse de l'échelle de gris, la susceptibilité magnétique ainsi que le degré d'humification. L'analyse du pollen dans la carotte DJH-1 révèle que le climat et la végétation ont significativement varié tout au long de ces derniers 42000 ans. La région de Dajiuhu, caractérisée aujourd'hui par des forêts denses était autrefois couvertes par des prairies alpine associés à une forêt clairsemée durant le DMG comme le laisse suggérer la prédominance des Cyperaceae et Poaceae dans les spectres polliniques. De faibles teneurs en matière organique (MOT) ainsi qu'un niveau de gris bas ont été aussi signalés durant la période glaciaire. La foret commençait à se reconstituer à partir de 14ka BP et les forets à arbre persistant ont atteint leur niveau maximale entre 10ka et 4ka BP, correspondant au maximum thermique de l'holocène. Les changements survenus après 4000BP ont été explorés aussi. La carotte GT-2 au sud de la chine sub-tropicale révèle quant à elle une végétation différente durant le dernier maximum glaciaire. Les spectres polliniques indiquent que cette période était caractérisée par des forêts de conifères associées à des forêts décidues. La prépondérance des genres décidus comme Carpinus, Betula et Corylus semble indiquer des conditions froides, alors que les pluies restaient abondantes. L'abondance du genre Tsuga, particulièrement entre 21 et 17ka BP suggère la descente de la limite forestière à des altitudes beaucoup plus basses. Les successions de biomes dans montagnes subtropicale du sud de la chine s'est étalée sur plusieurs phases : (1) la première se caractérise par des forêts décidues associées à des conifères (17-12.5ka BP), (2) la deuxième phase est dominée par les forêts decidues, (3) la troisième se caractérise par des forêts à arbres persistants associées à des arbres a feuilles caduques (12.5-9ka BP). Les deux dernières phases voient se succéder des forêts à arbres persistants (9-2.5ka BP) puis une forêt mixte, probablement liée à l'activité humaine. La comparaison entre les deux sites d'étude confirme que les changements de végétation durant le DMG étaient importants
Subtropical China is considered as an important region for biodiversity and a great natural reserve for endemic plant species, where the climate is mainly controlled by Asian Monsoon (AM). Since the recent decades, few continuous records so far covering the last glacial period in this area have been studied. In consequence, the past floristic evolution and vegetation-climate changes during particularly the Last Glacial period are still unclear. In this study, two cores from subtropical mountain wetlands were studied by means of palynology and other multidisciplinary proxies. The longer studied material covering the last 42 ka was obtained from a sub-alpine wetland in Dajiuhu, Shennongjia Mountains of central China, where the present-day vegetation is temperate deciduous forest mixed with some conifer taxa, and the climate is greatly influenced by the East Asian monsoon (EAM). The other material, core GT-2, collected in Gutian wetland of Guangxi Province in south China has an age of 21 ka can reflect the changes of evergreen forest and climate which is controled by the Indian monsoon (IM) overlapped with EAM. The aim of the current study is to reconstruct the regional vegetation and climate changes, and better understand the variability of two monsoon system (EAM and IM) since the last glacial period. Multi-proxy analysis including pollen and spore, stable carbon isotope (δ13C), sediment gray-scale (GS), magnetic suscepbitility (MS),peat humification (HD) and so on were perfomed for evaluating the regional environment changes. The overall result can be summarized as below: The pollen analysis from the DJH-1 core reveals that the past vegetation and climate in northern subtropical zone of central China varied significantly over the last 42 ka. The vegetation in Dajiuhu region, dominated by dense temperate forest today, was an alpine meadow with sparse mixed forest during the last glacial characterized by predominant Cyperaceae and Poaceae in the pollen spectra. Other proxies show that the lowest TOC content and lighter gray-scale in the glacial interval. The broadleaved forest began to return since 14 cal ka BP, and the evergreen broadleaved trees attained their highest level between ~10 and 4 cal ka BP, accordance in timing with the Holocene thermal maximum. A change at 4000 cal BP in pollen spretra was also investigated. The results from the core GT-2 in southern subtropical zone of China suggest a different replacement of vegetation during the last glacial. Pollen data indicate that a dense mixed forest of coniferous and deciduous broadleaved forest covered the southern subtropical mountains during the LGM (21-12.5 cal ka BP). The grass was however in low percentage. The high percentage of deciduous taxa such as Carpinus, Betula and Corylus indicate a colder condition, whereas the rainfall maintains abundant. The relatively high amount of Tsuga particularly during 21-17 cal ka BP suggests an important lowering of vertical forest belt. The biome changes in the southern subtropical mountains since the last glacial maximum can be outlined as follow: (1) deciduous and coniferous mixed forest (21-17 ka BP); (2) deciduous broadleaved forest (17-12.5 ka BP); (3) deciduous and evergreen mixed forest (12.5-9 ka BP); (4) evergreen broadleaved forest (9-2.5 cal ka BP) and (5) Mixed forest (from 2.5 cal ka BP) possible caused by human activity. The comparison of the two studied sites confirms that the shift of vegetation zone during the last glacial period is important. The alpine tree line might decend at an amplitude of more than 1000 m lower than that of today, and the temperate zone of deciduous broadleaved forest moved southwards to Guangxi Province (e.g. from about 30 to 22 latitude N ). The rapid increase of braodleved forest in central China began at about 10 cal ka BP, whereas the return to evergreen forest in Guangxi of southern subtropical zone took place at ca. 9 cal ka BP

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Macaluso-Galletta, Anna. "Etude des niveaux de contamination en HAP et des différentes variables biologiques dans les grains de pollen de pin (Pinus nigra) et de frêne (Fraximus excelsior) du sillon Mosellan." Metz, 2004. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2004/Macaluso_Galletta.Anna.SMZ0423.pdf.

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Ce travail a permis d'étudier la contamination atmosphérique en HAP des grains de pollen de Pinus nigra (pin) et de Fraxinus excelsior (frêne) dans le sillon mosellan. Ces espèces, considérées comme des plantes d'alignement courantes, sont capables d'accumuler les HAP présents dans l'atmosphère selon la nature de la source d'émission (urbaine ou industrielle). Les résultats ont mis en évidence une contamination du pollen des deux espèces choisies par les HAP : de 60 à 214 ug/g pour le frêne et de 101 à 229 ug/g pour le pin. Les HAP les plus lourds, notamment ceux contenant 5-6 cycles aromatiques, étaient les plus abondants. Vaux ont aussi mis en évidence une relation entre la présence des HAP dans les grains de pollen prélevés dans différents sites urbains et industriels et des modifications morphologiques et enzymatiques telles que la phosphatase acide et l'estérase, enzymes considérées comme paramètres de stress en réponse à la pollution atmosphérique
In this work, Pinus nigra (Black pine) and Fraxinus excelsior (European ash) pollens are used for the monitoring of PAHs in Metz area. In urban areas, these species are considered as ornamental trees. Moreover they have been shown to accumulate airborne PAHs. Depending on sources (urban or industrial). Pollens from both species were contaminated with PAHs, from 60 to 214 ug/g for the ash and from 101 to 229 ug/g for pine, especially 5/6 ring compounds. Total PAHs concentrations in pollen were positively correlated to acid phosphatase and esterase activities in different urban and industrial areas

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Macaluso-Galletta, Anna Ferard Jean-François. "Etude des niveaux de contamination en HAP et des différentes variables biologiques dans les grains de pollen de pin (Pinus nigra) et de frêne (Fraximus excelsior) du sillon Mosellan." Metz : Université Metz, 2008. ftp://ftp.scd.univ-metz.fr/pub/Theses/2004/MacalusoGalletta.Anna.SMZ0423.pdf.

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Teissier, Dominique. "Evaluation de la désensibilisation spécifique par les tests de provocation nasale avec des grains de pollen : étude en double-insu contre placebo avec un extrait d'allergoi͏̈de de fort poids moléculaire." Montpellier 1, 1988. http://www.theses.fr/1988MON11233.

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Guélin-Desfarges, Chantal. "Production de spores de penicillium roqueforti par fermentation en milieu solide sur substrats naturels et synthetiques." Clermont-Ferrand 2, 1988. http://www.theses.fr/1988CLF21101.

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Gouriveau, Emilie. "Résilience des écosystèmes : approche multiproxy de l'impact environnemental des activités humaines passées et récentes dans les Vosges du Nord (mines, verreries, activités militaires et agro-pastorales)." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCD039.

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Cette thèse vise à étudier les impacts des activités humaines passées sur les écosystèmes et notamment sur leur résilience dans la région des Vosges du Nord, et tente de combler les lacunes concernant l’histoire ancienne des sociétés. Dans ce but, quatre zones tourbeuses ont fait l’objet d’une étude multi-proxy, qui croise l’analyse des microfossiles polliniques et non-polliniques, des particules carbonisées ainsi que l’étude des sédiments. Les résultats ont permis de reconstituer la succession forestière depuis plus de 9000 ans cal. BP, qui suit globalement celle observée en Europe de l’Ouest avec cependant la persistance du pin du fait des conditions édaphiques autour des sites. Cette étude apporte également des éléments nouveaux sur l’indigénat de l’épicéa dans les Vosges du Nord, où les premiers indices de sa présence « naturelle » sont observés bien avant les plantations du XIXème siècle, alors que l’essence est actuellement considérée comme exotique dans les plans de gestion. Les premiers impacts anthropiques sur le couvert forestier sont visibles à partir du Néolithique initial et l’utilisation du paysage se diversifie et s’intensifie à partir de l’Âge du Fer et du Moyen Âge. Bien que les fonds de vallons et les zones humides ne soient pas épargnés, les activités humaines engendrent une forte régression de l’écosystème forestier – qui tient une place centrale dans l’utilisation du paysage – ainsi qu’une modification de sa composition spécifique. Bien que la mise en place d’un paysage morcelé ait généré une augmentation de la biodiversité, la pression anthropique a entraîné une légère perte de résilience de la forêt qui ne retrouve ses valeurs d’origine qu’après la modification de l’utilisation des paysages, les politiques de protection des forêts et les plantations des époques récentes
The object of this thesis is to study the impacts of past human activity on the ecosystems, particularly on their resilience in the Northern Vosges Mountains (NVM). This research also tries to fill existing gaps regarding ancient history of societies. To this end, four peaty areas were studied via a multi proxy approach that crosses multiples analyses of pollen, non-pollen palynomorph and carbonised particles, as well as the study of sediments. The results allowed us to reconstruct the forest succession from over 9000 yrs cal. BP that roughly follows the one studied in Western Europe, except for the persistence of Pinus that was allowed by the edaphic conditions around the sites. This study also provides new elements on the indigenous status of Picea in the NVM. In fact, we can observe the first traces of “natural” presence of this tree species long before the plantations of the 19th century even though it is usually considered as exotic in the management plans. The first anthropic impacts on the forest cover were noticed from the initial Neolithic and the landscape use diversifies and increased later, from the Iron Age and the Middle Ages. Even though the valley floors and humid areas were impacted as well, Human activities creates a strong decline in the forest ecosystem – the heart of landscape use - and a modification in its specific composition. Even though the landscape was then fragmented, thus increasing biodiversity, the anthropic pressure resulted in a loss of resilience in the forest. The later only recovers its original values with the modification of landscape use, forest protection policies and new plantations in recent years

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Sarda, Estève Roland. "Étude de la variabilité des bioaérosols atmosphériques en région île de France." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASJ004.

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Les bioaérosols atmosphériques sont des particules d’aérosols biologiques primaires en suspension dans l’air et référencés dans la littérature comme étant des: Primary Biological Aerosol Particles (PBAPs). Les PBAPs sont de tailles et de natures très différentes. Ils ont la capacité à agir comme noyaux de condensation nuageux ou de glace et participent ainsi au cycle de l’eau sur terre. Ils peuvent être transportés loin de leur zone d’émission et coloniser de nouveaux écosystèmes. Leur caractère allergisant ou pathogène a un impact sur la santé humaine et animale. Ce travail de thèse qui porte sur l’étude de la variabilité des bioaérosols atmosphériques en région île de France concerne les pollens, les moisissures et les bactéries. Les observations ont été réalisées dans la couche limite à l’observatoire du SIRTA/LSCE. Ce travail pionnier dans la région Francilienne a permis: (1) de documenter la variabilité interannuelle, saisonnière et journalière propre à chacun des PBAPs, (2) de déterminer leurs origines géographiques respective, (3) d’étudier les paramètres météorologiques qui gouvernent leur cycle de vie dans l’atmosphère. Mon dernier objectif (4) a été de developper un instrument de mesure en temps reel des PBAPs et plus specifiquement des pollens
Atmospheric bioaerosols are particles of primary biological aerosols suspended in the air and referred in the literature as: Primary Biological Aerosol Particles (PBAPs). PBAPs have very different sizes and coposition. They have the ability to act as cloud condensation nuclei or ice nuclei and thus participate in the water cycle on earth. They can be transported far from their sources and they can in this way colonize new ecosystems. Their allergenic or pathogenic propoeries have an impact on human and animal health. This work on the variability of atmospheric bioaerosols in the Ile de France region concerns pollens, molds and bacteria. The observations were made in the boundary layer at the SIRTA/LSCE observatory. This pioneering work in the Ile-de-France region had the objective to: (1) document the interannual, seasonal and daily variability specific to each of the PBAPs, (2) determine their respective geographical origins, (3) study the meteorological parameters that control their life cycle in the atmosphere. My last objective (4) has been to develop an on line instrumenst to measure in real time BPAPs concentrations with a focus on pollen

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Cerqueira, Sandro Melo. "Aspetos morfológicos dos insetos e sua importância na polinização." Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/17441.

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A maioria das plantas com flor é visitada por grande diversidade de insetos com diferentes formas e tamanhos, que acumulam grãos de pólen nos seus corpos. Neste trabalho analisou-se a relação entre os parâmetros morfométricos dos insetos visitantes florais (comprimento do corpo, envergadura das asas e comprimento da probóscide no caso dos lepidópteros) e número de grãos de pólen transportados. Verificou-se um efeito linear positivo relativamente ao comprimento do corpo dos insetos, ou seja, quanto maior o comprimento do corpo, maior o número de grãos de pólen transportados; também se verificou um efeito de alisamento negativo relativamente à envergadura, isto é, número de grãos de pólen transportados parece diminuir com o aumento da envergadura das asas. No caso dos lepidópteros, há uma correlação muito forte entre o comprimento da probóscide e comprimento do corpo, sugerindo que o efeito significativo do comprimento seja um proxy para a probóscide e não um efeito do comprimento; Abstract: Morphological aspects of insects and their importance in pollination Most flowering plants are visited by a great number of insects with different shapes and sizes, which accumulate pollen grains on their bodies. In this study we analyzed the relationship between the morphometric parameters of the flower visiting insects (body length, wing span, and the length of the proboscis in the case of Lepidoptera) and number of pollen grains carried. There was a positive linear effect regarding the body length of the insects, that is, the greater the body length, the higher number of pollen grains carried; it was also observed a negative smoothing effect regarding the wingspan, i.e. the number of pollen grains carried appears to decrease with increased wingspan. In the case of lepidoptera, there is a strong correlation between body length and proboscis, suggesting that this significant effect is a proxy for the proboscis rather than an actual effect of body length.

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RIBEIRO, Monique Hellen Martins. "Caracterização química e fitogeográfica de geoprópolis das espécies de abelhas nativas do Maranhão." Universidade Federal do Maranhão, 2017. https://tedebc.ufma.br/jspui/handle/tede/tede/1968.

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Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão
We analyzed the pollen spectrum of one hundred and thirty geopropollis samples of the following species of Melipona: M. fasciculata, M. flavolineata, M. seminigra and M. subnitida. Samples were collected in the municipality of Santa Luzia do Paruá, in the Alto Turi region, which belongs to the Amazon region, in the state of Maranhao. The objective of this study was to recognize the phytogeographic and chemical profile of the Melipona geopropolis samples and to help characterize the resin supplying vegetation for these bees. The geopropolis samples were collected monthly from December/2013 to December/2014 from nests kept in wooden boxes in a particular meliponary. The palynological analysis was done according to the standard methodology proposed by Barth (1998). The chemical profile of the samples was determined by high performance liquid chromatography (CLAE), liquid chromatography coupled to mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC / MS) analysis. And also included quantification of the content of total polyphenols (TPT) through the use of Folin-Ciocalteau reagents and sodium carbonate 20%; total flavonoids (TFT) by the photocolorimetric method with methanolic solution of aluminum chloride (AlCl3) 5%, and the antioxidant activity of the hydroalcoholic extracts of geopropolis by the DPPH free radical assay (Brand-Williams et al). A total of 148 pollen types were identified, distributed in 49 families, 108 genera and two unidentified types. In the geopropolis samples of M. subnitida 107 pollen types were distributed in 40 families and 72 genera. In the M. seminigra, 93 pollen types, 37 families and 70 genera were observed. For M. flavolineata were 98 pollen types, belonging to 33 families and 72 genera. In M. fasciculata there were 64 pollen types, 28 families and 53 genera, being therefore the one with the lowest pollen richness in the samples. Fabaceae presented the highest richness of pollen types (39 types), followed by Rubiaceae (11 types). The pollen types most common to Melipona species were: Attalea speciosa, Anacardium, Borreria verticilatta, Baccharis, Clusia, Chamaecrista, Croton, Euterpe/Syagrus, Eucalyptus, Hyptis, Mauritia, Mimosa pudica, M. caesalpinaefolia, Mouriri, Myrcia /Psidium, Protium And Symphonia globulifera, which characterized the phytogeographic profile of the geopropolis of this region. Aniardium, Ardisia, Baccharis, Caryocar, Clusia, Clusia grandiflora, Eucalyptus, Eupatorium, Hyptis, Myrcia/Psidium, Platonia insignis, Protium, Spondias, Symphonia globulifera, Tapirira and Vismia were the possible resin species suppliers for the Melipona geoprópolis . The presence of various compounds which have been tentatively characterized as quinic acid, benzophenone derivatives, O-glycosylated flavonoid and xanthones have been disclosed. The mangiferin compound was present in all samples. It was also verified the presence of benzophenones that appear to be involved in the biosynthesis of glycosylated xanthones. The extracts presented flavonoid contents above 2%, which allows them to be classified according to Brazilian legislation as a geopropolis with a high content of flavonoids. For the antioxidant activity a variation of 2.20 to 44.35% occurred. There was a variation in the content of phenolic compounds and flavonoids among the different samples of the four Melipona species analyzed. The results indicate that the bee species and the collection season, as well as the interaction between these factors, influence the concentration of bioactive compounds in the geopropolis. Thus, we believe that the results obtained contribute significantly to the geopropolis characterization of stingless bees from Amazonia Maranhense and show the importance of expanding the studies of chemical characterization and standardization of product quality parameters, since thisis a rich source of bioactive compounds with great pharmacological potential.
Analisou-se o espectro polínico de cento e trinta amostras de geoprópolis das seguintes espécies de Melipona: M. fasciculata, M. flavolineata, M. seminigra e M. subnitida. As amostras foram coletadas no município de Santa Luzia do Paruá, na região do Alto Turi, que pertence ao domínio amazônico, do estado do Maranhão. Este estudo teve como objetivo reconhecer o perfil fitogeográfico e químico de amostras da geoprópolis de Melipona e auxiliar na caracterização da vegetação fornecedora de resina para estas abelhas. As amostras de geoprópolis foram obtidas mensalmente de dezembro/2013 a dezembro/2014 a partir de ninhos mantidos em caixas de madeira em meliponário particular. A análise palinológica foi feita de acordo com a metodologia padrão proposta por Barth (1998). O perfil químico das amostras foi determinado por meio das análises de cromatografia líquida de alta eficiência (CLAE), cromatografia líquida acoplada a espectrometria de massa (CL-EM) e cromatografia gasosa acoplada a espectrometria de massa (CG/EM). Também foram quantificados o teor de polifenóis totais (TPT), por meio do uso dos reagentes Folin-Ciocalteau e carbonato de sódio a 20%; de flavonoides totais (TFT) por meio do método fotocolorimétrico com solução metanólica de cloreto de alumínio (AlCl3) a 5%, e da atividade antioxidante dos extratos hidroalcoólicos de geoprópolis pelo ensaio do radical livre DPPH (Brand-Williams et al. 1995). Foram identificados 148 tipos polínicos, distribuídos em 49 famílias, 108 gêneros e dois tipos não identificados. Nas amostras de geoprópolis de M. subnitida identificou-se 107 tipos polínicos distribuídos em 40 famílias e 72 gêneros. Nas de M. seminigra foram observados 93 tipos polínicos, 37 famílias e 70 gêneros. Para M. flavolineata foram 98 tipos polínicos, pertencentes a 33 famílias e 72 gêneros. Já em M. fasciculata foram 64 tipos polínicos, 28 famílias e 53 gêneros, sendo, portanto, a que apresentou menor riqueza de pólen nas amostras. Fabaceae apresentou a maior riqueza de tipos polínicos (39 tipos), seguida de Rubiaceae (11 tipos). Os tipos polínicos mais comuns às espécies de Melipona foram: Attalea speciosa, Anacardium, Borreria verticilatta, Baccharis, Clusia, Chamaecrista, Croton, Euterpe/Syagrus, Eucalyptus Hyptis, Mauritia, Mimosa pudica, M. caesalpinaefolia, Mouriri, Myrcia/Psidium, Protium e Symphonia globulifera, que caracterizaram o perfil fitogeográfico da geoprópolis dessa região. Enquanto Anacardium, Ardisia, Baccharis, Caryocar, Clusia, Clusia grandiflora, Eucalyptus, Eupatorium, Hyptis, Myrcia/Psidium, Platonia insignis, Protium, Spondias, Symphonia globulifera, Tapirira e Vismia foram as possíveis espécies vegetais fornecedoras de resina para a geoprópolis de Melipona. Revelou-se a presença de vários compostos, que foram tentativamente caracterizados como ácido quínico, derivados de benzofenonas, flavonoide O-glicosilado e xantonas. O composto mangiferina esteve presente em todas as amostras. Também foi verificada a presença de benzofenonas que parecem estar envolvidas na biossíntese de xantonas glicosiladas. Os extratos apresentaram teores de flavonoides acima de 2% que permitem classificá-los, de acordo com a legislação brasileira como geoprópolis com alto teor de flavonoides. Para a atividade antioxidante ocorreu uma variação de 2,20 a 44,35%. Houve uma variação no teor de compostos fenólicos e flavonoides entre as diferentes amostras das quatro espécies de Melipona analisadas. Os resultados obtidos indicam que a espécie de abelha e a época de coleta, bem como a interação entre esses fatores, influenciam a concentração de compostos bioativos na geoprópolis. Desta forma, acreditamos que os resultados obtidos contribuem significativamente para a caracterização da geoprópolis das abelhas sem ferrão proveniente da Amazônia Maranhense e evidenciam a importância de ampliarmos os estudos de caracterização química e padronização dos parâmetros de qualidade do produto, visto que este constitui uma rica fonte de compostos bioativos com grande potencial farmacológico.

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Cugny, Carole. "Apports des microfossiles non-polliniques à l'histoire du pastoralisme sur le versant nord Pyrénéen : entre référentiels actuels et reconstitution du passé." Phd thesis, Université Toulouse le Mirail - Toulouse II, 2011. http://tel.archives-ouvertes.fr/tel-00854984.

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Les microfossiles non-polliniques, des restes de divers organismes préservés dans les sédiments lacustres ou tourbeux, sont de plus en plus couramment employés en paléoécologie. Parmi ces microrestes, les spores de champignons coprophiles sont privilégiées dans les reconstructions des activités humaines telles que les activités pastorales. L'aptitude de ces spores à refléter la présence ou l'abondance des troupeaux n'est pas encore complètement comprise. Des analogues modernes ont été collectés dans deux zones d'estive, dans les montagnes du Pays Basque et d'Ossau. Des analyses de gradients contraintes par des variables environnementales ont permis d'identifier des assemblages non-polliniques associés à diverses conditions environnementales en contexte humide et terrestre. Un cortège d'ascospores de groupes coprophiles liées aux activités pastorales a pu être isolé. Les référentiels ont également fourni des informations sur la portée spatiale de l'information non-pollinique.Les microfossiles non-polliniques ont été étudiés dans quatre séquences tourbeuses en complément d'autres sources d'informations paléoenvironnementales (pollen, signal incendie). Ils ont fourni les informations sur les dynamiques des quatre sites durant l'Holocène et les périodes historiques. Les résultats des référentiels sont appliqués à l'interprétation des dynamiques pastorales. Les résultats modernes et fossiles montrent que la charge pastorale n'est pas le seul paramètre qui influence les signaux coprophiles ; ces spores pourraient avoir un potentiel d'indicateurs paléoenvironnementaux et pastoraux plus étendu qu'attendu.Les ascospores de groupes coprophiles sont décrites et illustrées ainsi que d'autres microfossiles fongiques, algaux et indéterminés.

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Tedesco, Marília. "CARACTERIZAÇÃO CITOGENÉTICA, COMPOSTOS FENÓLICOS E GENOTOXICIDADE DE Sambucus australis CHAM. & SCHLTDL. (ADOXACEAE)." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4893.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The economic potential of the medicinal species native to Brazil is huge, rendering it important to maintain the available plant genetic diversity via studies characterizing germplasm. Between these studies, highlights the characterization meiotic and pollen viability, genotoxic and antiproliferative activitie, beyond determination of phenolic compounds. Sambucus australis Cham. & Schltdl. ( sabugueiro ) numbers among the native species with medicinal potential, being widely used in the treatment of symptoms of skin eruptions, influenzas and common colds, for its diaphoretic, anti-inflammatory and analgesic actions. The objective of the present study was to investigate the antiproliferative, genotoxic and antigenotoxic activity of aqueous extracts of two accesses of S. australis, using the Allium cepa test, and to determine the phenolic compounds present in these extracts, as well as to analyze the meiotic behavior and estimate the pollen viability of different accesses of S. australis collected in Rio Grande do Sul state. Antiproliferative, genotoxic and antigenotoxic activities were determined by assessing the effect of aqueous extracts from the inflorescences and leaves of two accesses of S. australis, at concentrations of 3 g.L-1 and 12 g.L-1, on the cellular cycle of A. cepa. High performance liquid chromatography (HPLC) was employed to determine the phenolic compounds present in the extracts. For the meiosis analysis, slides were prepared by squashing technique of the anthers removed from the flower buds. The phases of association and distribution of the chromosomes were observed and meiotic indexes determined. To estimate pollen viability, the slides were prepared by squashing the anthers, comparing three stains: 2% acetic-orcein, 2% acetic-carmine, and Alexander´s reaction. All statistical analyses of the data were performed using the Scott-Knott test (p<0.05). Results showed that the aqueous extracts of S. australis exerted antiproliferative activity on the cellular cycle of A. cepa. The extracts prepared from S. australis (12g.L-1) leaves, for both accesses, also exhibited antigenotoxic activity. Chromatographic analysis disclosed the presence of the following compounds: gallic acid, chlorogenic acid, caffeic acid, ellagic acid, rutin, quercitrin, isoquercitrin, quercetin and kaempferol. Ultimately, the accesses of S. australis studied exhibited regular meiotic behavior, gametic number n=19, meiotic index > 90% and high pollen viability, being stain Alexander´s reaction the most efficient to estimate pollen viability in the specie.
O potencial econômico de espécies medicinais nativas no Brasil é imenso, sendo necessário conservar a diversidade genética vegetal disponível através de estudos de caracterização de germoplasma. Entre esses estudos, destacam-se a caracterização meiótica, a viabilidade polínica, a análise da atividade genotóxica e antiproliferativa, além da determinação dos compostos fenólicos. Dentre as espécies nativas com potencial medicinal, Sambucus australis Cham. & Schltdl. (sabugueiro) tem grande popularidade no tratamento sintomático de moléstias eruptivas, gripes e resfriados, por suas ações diaforética, anti-inflamatória e analgésica. O presente trabalho teve por objetivo verificar a atividade antiproliferativa, genotóxica e antigenotóxica de extratos aquosos de dois acessos de S. australis, através do teste de Allium cepa, bem como determinar os compostos fenólicos presentes nesses extratos, além de analisar o comportamento meiótico e estimar a viabilidade polínica de diferentes acessos de S. australis coletados no Rio Grande do Sul. Para determinação das atividades antiproliferativa, genotóxica e antigenotóxica, foi avaliado o efeito dos extratos aquosos das inflorescências e folhas de dois acessos de S. australis, nas concentrações de 3 g.L-1 e 12 g.L-1, sobre o ciclo celular de A. cepa. Os compostos fenólicos presentes nesses extratos foram determinados por meio da técnica de cromatografia líquida de alta eficiência (CLAE). Para a análise da meiose, foram preparadas lâminas pela técnica de esmagamento das anteras retiradas dos botões florais, observando-se as fases de associação e distribuição dos cromossomos, sendo também determinados os índices meióticos. Para estimativa da viabilidade polínica, as lâminas foram preparadas por esmagamento das anteras, comparando-se três corantes: orceína acética 2%, carmim acético 2% e reativo de Alexander. Todos os dados foram analisados estatisticamente pelo teste de Scott-Knott (p<0,05). A partir dos resultados, pode-se observar que os extratos aquosos de S. australis apresentaram atividade antiproliferativa sobre o ciclo celular de A. cepa. Os extratos preparados a partir das folhas de S. australis (12g.L-1), em ambos acessos, também apresentaram atividade antigenotóxica. A partir da análise cromatográfica foi possível determinar a presença dos seguintes compostos: ácido gálico, ácido clorogênico, ácido cafeico, ácido elágico, rutina, quercitrina, isoquercitrina, quercetina e canferol. Por fim, os acessos de S. australis estudados possuem comportamento meiótico regular, número gamético n=19, índice meiótico superior a 90% e alta viabilidade polínica, sendo o corante reativo de Alexander o mais eficiente para estimar a viabilidade polínica na espécie.

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Souza, Everton Hilo de. "Reprodução e hibridação interespecífica e intergenérica em bromeliáceas com potencial ornamental." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-17012014-105128/.

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As bromeliáceas são plantas ornamentais tropicais com uma grande diversidade de cores e formas que as tornam extremamente apreciadas. Os estudos da biologia floral, associado aos sistemas reprodutivos das espécies vegetais, são de fundamental importância para subsidiar a condução de programas de melhoramento genético e conservação de espécies, além de auxiliar na determinação do grau de compatibilidade entre genótipos e eventuais barreiras reprodutivas. O objetivo da presente tese é estudar aspectos da biologia floral e reprodutiva, conservação dos grãos de pólen, estudos de compostos voláteis em flores e hibridação interespecífica e intergenérica em Bromeliaceae com potencial ornamental. Foi observada grande variabilidade genética entre as espécies estudadas, no que diz respeito à morfologia dos grãos de pólen e estigma. Altas taxas de germinação e viabilidade polínica foram obtidas para as diferentes espécies, e a receptividade do estigma está relacionada com a antese. Essas características associadas têm grande importância para a fertilização e, consequentemente, para a produção de sementes, desta forma são essenciais para a produção de híbridos e conservação de espécies. Para a conservação dos grãos de pólen, o melhor resultado foi obtido com a desidratação prévia por 3 h em sílica e conservação em nitrogênio líquido (-196°C). A partir de flores de treze espécies, foram identificados 71 compostos voláteis, alguns deles com importância na indústria de alimentos, cosméticos, perfumes, indústria química e farmacêutica. Dentre as dezessete espécies estudadas, mais de 50% apresentaram autoincompatibilidade, e algumas apresentaram autogamia, demonstrando que essas espécies apresentam autopolinização espontânea. Agamospermia foi observada em apenas duas espécies. Noventa e cinco combinações entre 17 espécies de Aechmea e Ananas (Bromelioideae) e Alcantarea e Vriesea (Tillandsioideae) foram realizadas. O sucesso nas hibridações corresponde a 33,74%, sendo que 24,96% envolveram as variedades botânicas do gênero Ananas. Entre as hibridações intergenéricas, apenas duas combinações foram obtidas com sucesso: V. michaelii x Al. nahoumii e V. simplex x Al. nahoumii. As possíveis causas da autoincompatibilidade e incongruência nesses cruzamentos estão relacionadas a diferentes eventos no tubo polínico, como: deposição irregular de calose no tubo polínico; enovelamento dos tubos polínicos no estilete; paralisação do crescimento do tubo polínico no estilete, entre outros. Sugere-se que a autoincompatibilidade seja gametofítica, evitando a autofertilização. Estudos mais aprofundados contribuirão para caracterizar as causas e as potenciais medidas para superar a autoincompatibilidade. Os resultados aqui apresentados trazem contribuições importantes para estudos de hibridação em Bromeliaceae, visando à obtenção de novidades para o mercado de plantas ornamentais, bem como contribuições para a caracterização e conservação de espécies dessa importante família
Bromeliads are tropical ornamental plants with a wide variety of colors and shapes that make them widely and extremely appreciated. The study of aspects of the floral biology, associated with the reproductive systems of these species are of fundamental importance for breeding and species conservation programs, assisting in the determination of the degree of compatibility between combination of genotypes, as well as potential reproductive barriers. The aim of this research is to study aspects of floral and reproductive biology, conservation of pollen grains, studies of volatile compounds in flowers and intergeneric and interspecific hybridization in Bromeliaceae with ornamental potential. High genetic variability was observed among the species studied, regarding the morphology of the pollen grains and stigma. High rates of germination and pollen viability were observed for the different species, and stigma receptivity showed the highest at anthesis. These characteristics are of great importance for fertilization and further seed production, thus are essential for the production of hybrids and species conservation. Preservation of pollen grains, showed the best results with a 3 h dehydration pre-treatment in silica and conservation in liquid nitrogen (-196°C). A large number of volatile compounds, totally 71, were identified from flowers of thirteen species. Some of these compounds have already been shown to be important in the food industry, cosmetics, perfumes, chemical and pharmaceutical industry. Among the seventeen species, more than 50% presented selfincompatibility and some species presented autogamy, demonstrating that these species present spontaneous self-pollination. Agamospermy was observed in only two species. Ninety-five combinations among 17 species of Aechmea and Ananas (Bromelioideae) and Alcantarea and Vriesea (Tillandsioideae) were performed, with a 33.74% rate of success, with 24.96% involving the botanical varieties of Ananas. Only two, among the intergeneric combinations, were successful, V. michaelii x Al nahoumii and V. simplex x Al nahoumii. Possible causes of self-incompatibility and incongruity in these combinations were related to different events during pollen tube growth, such as the irregular deposition of callose in pollen tubes; entangled pollen tubes in the style; arrest of pollen tube growth in the style, among others. We suggest that the self-incompatibility is gametophytic, preventing selffertilization. Further studies will help to characterize the causes and potential measures to overcome self-incompatibility. The results provide important contributions to studies of hybridization in bromeliads, aiming to produce new hybrids for the ornamental plants market, as well as contributions to the characterization and conservation of this important family of plants

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Tiwari, Suresh Chandra. "Ultrastructual studies on tapetum and pollen development." Phd thesis, 1985. http://hdl.handle.net/1885/142509.

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Pereira, Sónia Gonçalves. "Contribution to pollen automatic identification and assessment of atmospheric pollutants effects on pollen grains." Master's thesis, 2020. https://hdl.handle.net/10216/129665.

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Pereira, Sónia Gonçalves. "Contribution to pollen automatic identification and assessment of atmospheric pollutants effects on pollen grains." Dissertação, 2020. https://hdl.handle.net/10216/129665.

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MacInnis, Gail M. "Measuring and Modelling the Dispersal of Pollen and Spores by Wind." Thesis, 2012. http://spectrum.library.concordia.ca/974683/1/MacInnis_MSc_F2012.pdf.

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Our present understanding of pollen dispersal by wind (anemophily) is quite limited. Due to the stochastic and complex nature of anemophily, modelling the dispersal patterns of the pollen and seeds of wind pollinated plants is not an easy task. The majority of the existing dispersal models are varied and have many conflicting predictions of pollen dispersal distances and concentrations from a source. These discrepancies between models reflect the lack of both short and long distance dispersal data, limiting the ability to seriously test the validity of these models. The main objective of this study was to measure ambient pollen concentrations of various tree and shrub species at both short and long distances from the source. A secondary objective was to measure the parameters involved in the dispersal process of anemophilous pollen and subsequently use these parameters and the empirical data collected to test the accuracy of three analytical mechanistic models of pollen and seed dispersal. The applications of such models are extensive; besides being of use to the allergy-suffering population, present-day issues such as climate change, pollen contamination in GMO crops, and landscape fragmentation raise concerns about whether plants will be able to adapt, disperse, and reproduce effectively in such rapidly changing environments.

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ŠOLÁ, Jitka. "Včelařsky významné pylodárné rostliny jarního a časně letního aspektu na území Zbudovských Blat (okolí obce Hlavatce)." Master's thesis, 2018. http://www.nusl.cz/ntk/nusl-376077.

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Objective of the theses was to determine the botanical origin of bee-collected pollens using pollen analysis. The beehive, from where the pollen came from, is located in Hlavatce, which is 20 km far from České Budějovice. Bee-collected polens was obtained via pollen trap, which was put on the beehive once a week for 24 hours between 17th March to 6th June 2017. Pollens were dried, sorted according to the color shades, and the partial color samples were weighed on the analytical scales. The pollen analysis took place at a microscope magnification of 400x. The characteristics of exine (sculpture) and quantity and type of apertures were observed. The size of the grain, which was measured always in 50 pollen grains, helped to classify the plant species. Using the Shannon-Wiener Diversity Index, the bee's preferences were assessed in individual samples. The work is supplemented with photos of selected pollen grains.

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ŠEMRO, Martin. "Včelařsky významné pylodárné rostliny jarního a časně letního aspektu v okolí Volar na území CHKO Šumava." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-174052.

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Objective of the work was to identify with using pollen analysis botanical origin of bee pollens. Pollen analysis consisted in the distribution of samples to individual sub-samples . Samples were weighed and a part of them was dissolved in a solution of glycerin and water. Dissolved samples were viewed under a microscope. Pollen was removed by the beekeeper Mgr .Milan Trhlín with using a device called pollen catcher. The samples were collected in the year 2011 in the spring and early summer period from beehive location on the hill Lískovec, of the protected landscape Šumava 1,8 km west of city Volary, at a time of 25. march to 24. june. Another objective of the work was with using phytocenology study, in the distance 1,5 km from the beehive habitat, evaluate the structure of plant association from the point of nutrition honeybees. The work also includes evaluation preference bees for individual plant species. There were detected, that bees prefer the plants that provide the best digest pollen and the plants which grows up to 1,5 km from beehive habitat. There were distinguised 32 types of pollen grains.

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Lu, Chun-Ying, and 呂俊穎. "The study on applying the visualization of feature map and convolutional neural network to pollen grains classification." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/66p652.

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碩士
國立中興大學
資訊管理學系所
106
Pollen grains is widely used in many fields. For example, bee pollen has high nutritional value and contributes to the beauty and health of human beings, pollen may cause pollen allergies, pollen fossils can be used to study the reconstruction of paleoenvironment and present a variety of paleoclimate features. The above application shows that the pollen grains have a very high research value.The classification of pollen grains is traditionally artificial. However, manual classification not only requires experts to classify pollen grains, showing that the classification of pollen grains requires high proficiency and cost, but also when the dataset is more than 1000 images, the classification task will become time-consuming. Therefore, the concept of automatic classification of pollen grains is generated. Generally, for the classification of pollen grains, the image processing method is used to extract features at first, after obtaining features, the next step is to classify with machine learning methods, the accuracy rate is approximately between 64% and 95%. As we mentioned, feature extraction is time consuming. Above all, if the appropriate features are not extracted, the accuracy of the classification will be affected. In recent years, due to the vigorous development of deep learning, Convolutional neural network(CNN) has also been applied to the study of pollen grains. Because the convolutional layer of the CNN has the feature extraction function, it is able to eliminate the need for complex pre-processing steps and achieving high classification accuracy. Daood et al. classified the pollen grains with CNN in 2016, reaching an accuracy of 89.95% after data augmentation and transfer learning. This study used a dataset containing a total of 805 images, 23 classes. The results of the experiment include two phases. In the first phase, 805 images were divided into grayscale and RGB with CNN classification of three different architectures. The best accuracy is RGB images with Simple CNN achieving 81.55%, which is a significant improvement over [1] using the same data set. The second part using general data augmentation augmented the images to 8714 by rotating, resizing, and shearing, and then using Simple CNN to establish a predictive model, the experimental results have achieved an accuracy of 95.95% and a precision of 96.09%. Compared with the research using deep learning, there is not much difference in the accuracy of 89.95% obtained from [2] containing 30 types of dataset, also, our research collected 9 classes of pollen grains and combined with original dataset, following the research flowchart, the 32 classes dataset reached 95.67% of accuracy, proving the generalization of Simple CNN. Because the traditional feature extraction method can explain the importance of the extracted pollen features, this study also observed the features of the pollen grains through visualization of the convolution layer, and found that the same type of pollen grains, the locations of filters will be similar and different types of pollen grains can be distinguished by their different color features, texture features or shape features.

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Κούτουλα, Μαργαριτα. "Συμβολή στη δημιουργία γυρεολογικού άτλαντα της χλωρίδας της Πανεπιστημιούπολης Πατρών." 2004. http://nemertes.lis.upatras.gr/jspui/handle/10889/429.

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Στόχος της παρούσας εργασίας είναι η συμβολή στη δημιουργία ενός γυρεολογικού άτλαντα για τα φυτά της Πανεπιστημιούπολης Πατρών. Γι’ αυτό το σκοπό, στη διάρκεια ενός χρόνου συλλέχθηκαν και αναγνωρίστηκαν 150 δείγματα από την Πανεπιστημιούπολη και δημιουργήθηκε ένα «Herbarium». Από κάθε είδος συλλέχθηκε ένας μεγάλος αριθμός ανθέων για επεξεργασία στο εργαστήριο. Στη διαδικασία αυτή ελήφθη το γυρεολογικό υλικό και ετοιμάστηκαν τα μικροσκοπικά παρασκευάσματα με τη μέθοδο ακετόλυσης Erdtman. Μελετήθηκαν οι εξής οικογένειες Apocynaceae (1), Boraginaceae (7), Buxaceae (1), Capparaceae (1), Caprifoliaceae (1), Caryophyllaceae (2), Compositae (15), Convolvulaceae (2), Cruciferae (2), Dipsacaceae (2) Euphorbiaceae (1), Geraniaceae (1), Gramineae (2), Iridaceae (2), Labiatae (9), Leguminosae (18), Liliaceae 6, Malvaceae (2), Oleaceae (3), Oxalidaceae (1), Papaveraceae (2), Plantaginaceae (1), Pinaceae (1), Pittosporaceae (1), Primulaceae (1), Ranunculaceae (4), Resedaceae (1), Scrophulariaceae (2), Solanaceae (1) Umbelliferae (3) Urticaceae (2), Verbenaceae (2). Μετά έγιναν για κάθε είδος τουλάχιστον 150 μετρήσεις των χαρακτηριστικών διαστάσεων των γυρεοκόκκων του που είναι η πολική (Ρ) και η ισημερινή (Ε) απόσταση και ο λόγος της πολικής προς την ισημερινή απόσταση (Ρ/Ε). Στη συνέχεια πραγματοποιήθηκε η στατιστική επεξεργασία των μετρήσεων και η εξαγωγή των μέσων τιμών και της διασποράς τους. Για κάθε είδος, περιγράφτηκαν τα μορφολογικά και ανατομικά χαρακτηριστικά στοιχεία των γυρεοκόκκων. Τέλος, η μορφολογική περιγραφή του γυρεοκόκκου ολοκληρώθηκε με τη φωτογράφηση στο Ο.Μ. των παρασκευασμάτων. Σε μερικά είδη παρατηρήθηκαν διαφορές ως προς τις βιβλιογραφικά δεδομένα από άλλες περιοχές, όσον αφορά το ανάγλυφο, την μορφολογία των ανοιγμάτων (Anemone pavonina) το μέγεθος των γυρεοκόκκων (Vicia villosa, Pimpinella peregrina, Onopordon illyricum κ. α.) Στο Onopordon illyricum L. βρήκαμε γυρεοκόκκους με Ρ = 59, 35 μm, Ε = 55,14 μm ενώ στη βιβλιογραφία αναφέρονται Ρ = 40 – 45 μm και Ε = 39 - 45 μm. Στο είδος Anemone pavonina Lam. η βιβλιογραφία αναφέρει πολυπορώδεις γυρεοκόκκους ενώ στο δικό μας υλικό οι γυρεόκοκκοι φαίνονται παντοκολπικοί. Στην Vicia villosa Roth.. βρήκαμε Ρ = 42,32 μm και Ε = 20,61 μm ενώ βιβλιογραφικά αναφέρονται τιμές Ρ = 28 – 35 μm και Ε = 14 – 21 μm. Αυτή η διαφοροποίηση είναι μια γεωγραφική διαφοροποίηση που σχετίζεται και συνοδεύεται και από μορφολογικές και γενετικές διαφορές.
The aim of the present study is the construction of a pollen atlas with regard to the plant species in the area of the University of Patras, Greece. For this purpose, 120 different samples were collected and characterized and a «Herbarium» was created. From each of the species, a big number of flowers were collected for further processing in the lab. Fresh polliniferous material was procured randomly from several plants growing in the field of the University of Patras. For light optical microscope (LO) studies pollen were acetolyzed following the protocol of Erdtman (1952). The plant taxa studied here belongs to the following families: Apocynaceae (1), Boraginaceae (7), Buxaceae (1), Capparaceae (1), Caprifoliaceae (1), Caryophyllaceae (2), Compositae (15), Convolvulaceae (2), Cruciferae (2), Dipsacaceae (2) Euphorbiaceae (1), Geraniaceae (1), Gramineae (2), Iridaceae (2), Labiatae (9), Leguminosae (18), Liliaceae 6, Malvaceae (2), Oleaceae (3), Oxalidaceae (1), Papaveraceae (2), Plantaginaceae (1), Pinaceae (1), Pittosporaceae (1), Primulaceae (1), Ranunculaceae (4), Resedaceae (1), Rubiaceae (1), Scrophulariaceae (2), Solanaceae (1) Umbelliferae (3) Urticaceae (2), Verbenaceae (2). At least 150 measurements were taken for each plant taxon pollen grain preparation, in order to calculate the mean value of the polar (Ρ) and equatorial (Ε) dimensions of the taxon’ s pollen grains, as well as, the ratio Ρ/Ε. Statistical analysis was performed and the mean values were recorded. The morphology and anatomy of each species pollen grains were determined. The study was completed by taking LM pictures of all pollen grains. In some of the species studied in the area we have noticed some differences between the pollen grains dimensions, or even the morphology of the pollen grain surface, and of the same taxa that are described from other countries (Anemone pavonina Lam., Onopordon illyricum L., Vicia villosa Roth., Pimpinella peregrina L.) In Onopordon illyricum L. we have found pollen grains with P = 59,35 μm, Ε = 55,14 μm and the same species from Spain is described with P = 40 – 45 μm ανδ Ε – 39 – 45 μm. Anemone pavonina Lam. is referred to have poliporate pollen grains, in our material it seems to have policolpate pollen grains. In Vicia villosa Roth. From Spain is referred P = 28 – 35 μm and E = 14 – 21 μm, and we found P = 42,32 μm and E = 20,61 μm. This might be a geographic differentiation that is normal in pollen grains and is related with other morphological and genetic differences.

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PETROVÁ, Jana. "Význam produkce a kvality pylu letní a podzimní pylové snůšky pro včelstvo (případová studie z okolí obce Volary - CHKO Šumava)." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-188502.

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Objective of the work was to identify with using pollen analysis botanical origin of bee-colected pollens collected from beehive station Lískovec near the town Volary in the Protected Landscape Area of Šumava. Bee-collected pollens were collected once a week from one honey bee colony with using of a pollen trap. The time of collection was summer and late summer period from 22 June to 11 September 2010. Bee-collected pollens were dried, categorized by color, weighed and observed using the microscope. Pollen grains were determined by the number and type of apertures, shape, sculpture and size. Size of pollen grains was measured on at least 50 pollen grains of one type. In each microscopic slide were counted at least 500 pollen grains. The proportion of plant species in the sample was expressed as a percentage and the importace of plant species was evaluated in the diet of honey bees in the area of interest. Selected samples of bee-collected pollens from beehive station Lískovec and also from beehive station Dobčice were investigated for protein content and amino acid composition. Pollen belonging to Polemonium coeruleum, Trifolium pratense and Trifolium repens was evaluated as an important source of protein and amino acids for honey bees. The concentration of essential amino acids expressed as percentages of total amount of amino acids did not differ significantly between samples of bee-collected pollen. Another objective of the work was to compare the results from the area of interest with the results processed in the similar study from beehive station Dobčice in the northern area of the landscape Blanský les. The work also includes statistical evaluation of dominance, frequency, Shannon-Wiener index of diversity and variability between samples and species. The work is complemented by photographs of selected pollen grains.

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陳亭妤. "A Study on the Morphology of Leaves and Pollen Grains and Genetic Diversity Analysis by ISSR Markers in Coleus." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06301977843714792073.

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碩士
國立嘉義大學
園藝學系研究所
99
Leaf morphology and anatomy, pollen grains morphology and pollen viability as well as inter simple sequence repeat (ISSR) molecular markers were carried out on the identification , classification and genetic diversity of 21 coleus cultivars. In the study of leaf morphology, 5 leaf shapes with ovate, lance-ovate, widely ovate, very widely ovate and cordate etc. were classified. Four leaf apexes were with acuminate, acute, obtuse and rounded. Six leaf bases were with narrowly cuneate, cuneate, obtuse, rounded, truncate and cordate etc. Five margin type of leaves in 21 coleus cultivars were with crenate, crenulate, pinnately cleft, pinnately parted and pinnately divided etc . The anatomical transverse sectional structure of leaf in 21 coleus cultivars were also studied. Upper epidermis was a neat single layer of epidermal cell. The lower epidermis wasn’t as neat as upper epidermis, it appeared curved. The palisade tissue consisted of one or two arrangement of neat layers. The spongy cells were irregular round shapes mingled with intercellular spaces. There were some significant difference also exited in the transverse section structure of leaf and could be used to separate in the 21 coleus cultivars .The pollen grain morphology of 16 coleus cultivars was investigated by LM and SEM. The major aperture shape of coleus pollen grains were 6-colpate, with 7-colpate and 8-colpate occasionally. The aperture situated at the equator, the colpus with granules. The sculpture was reticulate. the external aperture of pollen in the 16 coleus cultivars were similar , but percentage of pollen aperture with 6-colpate, 7-colpate and 8-colpate in the 16 coleus cultivars were different . The pollen viability of six coleus cultivars (CH007, CH010, CH011, CH017, CH021 and CH022) were tested by Alexander solution. The pollen sampled at 1-7 days after anthesis in summer and winter. In summer, the pollen viability of CH021 and CH011 were highest with 23.9% and 20.0%; that of CH010 was lowest (1.6%). In winter, the pollen ability of CH007 was highest (74.7%); that of CH010 was lowest (4.9%).The pollen ability in winter was higher than those of summer. According to ISSR analysis, six ISSR primers with polymorphic pattern were UBC830, UBC836, UBC841, UBC861, UBC885 and UBC900 and used for the trial. In 21 coleus cultivars, 82 bands were amplified and they were all polymorphism, the percentage of polymorphism were 100%. The similarity coefficient were between 0 and 0.6885. Cluster analysis by using UPGMA method showed that 21 coleus cultivars could be divided to nine groups based on similarity coefficient with 0.43 as the critical point. The group 1 consisted of CH001, CH017, CH020, CH018, CH028, CH012, CH016, CH023, CH009 and CH024; the group 2 consisted of CH004 and CH006; the group 3 was CH025; the group 4 consisted of CH007 and CH011; the group 5 was CH021; the group 6 was CH002; the group 7 consisted of CH022 and CH027; the group 8 was CH010; the group 9 was CH003.

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Li, Zhen. "Reconstructing Holocene East Asian climate and oceanographic history of the northern South China Sea: high-resolution records of pollen, spores, and dinoflagellate cysts." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/10473.

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This study contributes to developing terrestrial and marine palynological indicators of winter or summer monsoon signals as well as oceanographic environments of the South China Sea (SCS). The high-resolution reconstructions of Holocene East Asian Monsoon (EAM) climate and oceanographic condition of the northern SCS provide insights into regional climate events in the western low-latitude Pacific Ocean and their impacts on local oceanography and ecology. Sediment trap samples from the southwest Taiwan waters of the SCS in winter monsoon (March-April) and summer monsoon (July-August) seasons identify abundances of Pinus and Ulmus pollen as indicators of the winter monsoon whereas fern spores appeared to be indicators of the summer monsoon. The increased fluxes of dinoflagellate cyst (DC) taxa during summer are correlated with decreased sea-surface salinity (SSS) associated with nutrient-rich river inputs. DC distributions across the SCS show that some taxa are good indicators of changes in sea-surface temperature (SST), SSS, water depth and chlorophyll-a (chl-a) concentrations associated with EAM and oceanographic conditions. In particular, the concenrations of Brigantedinium spp. and cysts of Protoperidinium together with Echinidinium spp. are positively correlatd with SST in January and SST in July, and chl-a concentrations, respectively, which are linked to past monsoon strength and primary productivity. In total, four high cyst concentration regions have been observed off southern Vietnam, Borneo, Hainan, and South China. High-resolution palynological records from a sediment core in the northern SCS reflect several EAM climatic and oceanographic events over the last 12.5 kyr. A short-term Impagidinium decrease implied that the Taiwan Strait opened at ~11.7–11.0 cal kyr BP, with reduced Kuroshio Current influence when the East China Sea waters entered through the strait. Three Holocene relative sea-level stages were identified in the palynomorph records. The highest herb pollen abundances were observed before ~10.4 cal kyr BP, reflecting the shortest distance from the grassland sources on the exposed shelf at the low sea-level stand. High Brigantedinium and cysts of Protoperidinium abundances also indicate a near-shore environment. During ~10.4- ~6.8-6.0 cal kyr BP at the rising sea-level stage, fern spore abundances increased and DC abundances decreased. Consistently low total DC concentrations and high fern spore abundance were observed after ~6.8-6.0 cal kyr BP when the present oceanographic conditions were formed. Increased abundances of Pinus pollen reflected three strengthened winter monsoon intervals at ~5.5, 4.0 and 2.5 cal kyr BP under the present oceanographic conditions. The highest Dapsilidinium pastielsii abundances reflected the warmest interval at ~6.8-5.5 cal kyr BP of the northern SCS.
Graduate
2019-12-13

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Salter, Joshua. "Comparative morphological, anatomical and embryological studies of Prumnopitys taxifolia and P. ferruginea (Podocarpaceae), and the hydrodynamics of their saccate pollen grains." 2004. http://hdl.handle.net/2292/2566.

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Prumnopitys taxifolia (Banks et Sol. ex D. Don) de Laub. (matai) and P. ferruginea (D. Don) de Laub. (miro) are two New Zealand podocarps with morphologically very different reproductive structures. In P. taxifolia the pollen cones are sessile on spicate fertile branches, whereas in P. ferruginea they are solitary on short scaly peduncles. Likewise, in P. taxifolia the ovulate strobilus is an attenuated spicate structure bearing globose seeds, whereas in P. ferruginea the reduced ovulate strobilus bears a dorsi-ventrally flattened, usually solitary seed on a slender scaly peduncle. Such differences throw doubt on the validity of the current delimitations of the genus Prumnopitys. A comparative embryological study of these two species was done in parallel with a morphological and anatomical study of the reproductive structures to fill gaps in their known reproductive life cycles, and to determine whether there are any differences in the male and female cones or in their embryogeny that are of taxonomic significance at the generic level. In addition the hydrodynamic properties of their saccate pollen grains were compared with that of the pollen of several other conifers and the spores of three ferns and one lycopod. Morphology and Embryology Embryologically these two species are shown to be more similar to each other and to the Chilean Prumnopitys andina than to other podocarp genera. For instance, in both species: the long tapered archegonia have prominent neck cells with a thickened cap overlying them; five free nuclear mitoses occur before cell formation in the proembryo; meiosis can result in both linear and non-linear tetrads of megaspores; the microgametophyte typically forms 7 or 8 prothallial cells before dispersal. However, new morphological and anatomical differences have emerged from this study. In the pollen cones of P. taxifolia, the microsporangia are free with a transverse stomium located close to the cone axis; in P. ferruginea they are fused with the transverse stomium located basally. In P. taxifolia ovules, a tanniniferous layer develops in the epimatium and not in the integument, and fusion of epimatium/integument/nucellus is greatest dorsi-ventrally; in P. ferruginea ovules a prominent tanniniferous layer develops only in the integument, and fusion of epimatium/integument/nucellus is greatest laterally. Furthermore, observations of insect predation point to biochemical differences between P. taxifolia and P. ferruginea. An undescribed species of gall midge appears to be specialized exclusively for the P. taxifolia life cycle, and several other insect larvae prey on the developing and mature seeds, whereas the ovules/seeds of P. ferruginea appear to have almost no insect predators. Morphologically, anatomically and biochemically, P. taxifolia and P. ferruginea may therefore be sufficiently different to warrant being two separate genera; comparable differences have been used to distinguish other genera in the Podocarpaceae. Since embryogeny is likely to be under less evolutionary pressure than morphology and anatomy, and since P. taxifolia (along with P. andina) is regarded by some as basal in the conifers, with P. ferruginea less so, their embryological similarity does not necessarily indicate close relationship, only that they are closer to each other than to the other podocarps. Although their morphological and anatomical differences may be of taxonomic significance, a better understanding of the other species currently in Prumnopitys is necessary before the relationships within the genus can be clarified. Pollen Hydrodynamics Despite the morphological differences in their ovulate cones, P. taxifolia and P. ferruginea have very similar pollination mechanisms involving an inverted micropyle, a pollination drop and saccate pollen. Saccate grains have sometimes been referred to as 'non-wettable' due to their buoyant properties, while non-saccate pollen grains have been described as 'wettable'. The hydrodynamic properties of saccate pollen grains of seven podocarp species in five genera, Dacrydium Sol. ex G. Forst., Dacrycarpus (Endl.) de Laub., Manoao Molloy, Podocarpus L'Hér. ex pers. and Prumnopitys Phil. have been tested in water, together with saccate and non-saccate pollen of four other conifer genera, Cedrus Trew (Pinaceae), Cephalotaxus Siebold & Zucc. ex Endl. (Cephalotaxaceae), Cupressus L. (Cupressaceae) and Phyllocladus Rich. ex Mirb. (Phyllocladaceae), and spores of three fern species and one lycopod species. All four spore types studied were non-wettable, whereas the bisaccate and trisaccate pollen types, like all the other conifer pollen types, were wettable, enabling the grains to cross the surface tension barrier of water. Once past this barrier, grain behaviour was governed by presence or absence of sacci. Non-saccate and vestigially saccate grains sank, whereas saccate grains behaved like air bubbles, floating up to the highest point. In addition, the grains were observed to float in water with sacci uppermost, consistent with the suggestion that distally-placed sacci serve to orientate the germinal furrow of the pollen grain towards the nucellus of an inverted ovule. Observations of pollen grains in the pollen chambers of naturally pollinated Prumnopitys ovules confirmed this. The combination of buoyancy and wettability in saccate pollen has implications for the efficiency of the typical podocarp pollination mechanism. Since saccate pollen, inverted ovules and pollination drops are also characteristic of the Pinaceae, the similarities in the pollination mechanisms and the pollen grains of P. taxifolia and P. ferruginea have no taxonomic significance at the generic level.

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Bode, Thomas. "Ein Datenbanksystem (P.A.S.T) zur Verarbeitung und Interpretation von palynologischen Daten aus dem Paläogen Mitteleuropas mit Diversitätsbetrachtungen." Doctoral thesis, 2001. http://hdl.handle.net/11858/00-1735-0000-0006-B25B-E.

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