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Rocha, Fabíola Carla da [UNESP]. "Ictiofauna associada à Typha angustifolia (Angiospermae) em riachos." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/87616.
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As plantas aquáticas são importantes componentes dos ecossistemas lóticos e lênticos. Como conseqüências de transformações ambientais, algumas podem se tornar dominantes, sendo que as plantas aquáticas do gênero Typha são bem sucedidas em brejos e alagados, podendo também ser encontradas em córregos e ribeirões. O presente estudo foi realizado com o objetivo de avaliar a influência de T. angustifolia para a ictiofauna em riachos. Foram estudados seis riachos na bacia do Alto Rio Turvo, Estado de São Paulo, desprovidos de vegetação ripária nativa, mas com abundância de T. angustifolia no hábitat interno e ripário. Por meio da análise de mapas de cobertura do solo, observou-se que T. angustifolia está amplamente distribuída nas zonas ripárias ao longo das drenagens estudadas. Os riachos com as maiores proporções de T. angustifolia nas zonas ripárias também apresentaram a menor riqueza de espécies e abundância de peixes. A baixa semelhança na composição e estrutura da ictiofauna entre os períodos sazonais, a grande quantidade de espécies tolerantes e o fato de que a maioria das espécies foi ou acessória ou acidental, sugerem uma dinâmica populacional do tipo “fonte e dreno” nos riachos estudados. Desta forma, os trechos livres de Typha atuam como “fontes”, provendo indivíduos que, por migração, podem ocasionalmente explorar os trechos com elevada abundância de T. angustifolia. Nestes trechos, que teriam o papel funcional de “drenos”, as condições ambientais são pouco apropriadas para a manutenção de uma comunidade diversa e residente de peixes. Os indivíduos dos trechos “fonte” à montante e à jusante que para ali migram se beneficiam de uma oferta relativamente constante de alimento, embora pouco variada (principalmente larvas aquáticas de Chironomidae e detritos), e abrigos (raízes de Typha).
Aquatic plants are a major component of lenthic and lotic ecosystems. As consequences of environmental changes, some species may became dominant, being that aquatic plants of the genus Typha are a well successful group of weeds in swamps and flooded areas, but also found in headwaters and large streams. This study was made with the aim to investigate the influences of T. angustifolia on the fish assemblages in streams. A total of six streams in the Upper Rio Turvo basin, São Paulo state, without riparian vegetation but with abundance of T. angustifolia in the instream and riparian habitat, were studied. By analyzing soil coverage maps, it was registered that T. angustifolia was widespread in the riparian zones along studied drainages. Streams with the largest proportions of T. angustifolia along riparian zones were also those with lowest fish species richness and abundance. Low similarity in the composition and structure of fish fauna between seasonal periods, together with a large number of tolerant species, and the fact that most species are accessory or accidental, suggest a “source and sink” population dynamic in the studied streams. Thus, free Typha stretches play as a “source” habitat, providing individuals that, by migration, may occasionally explore stretches with large abundance of T. angustifolia. In these stretches, which play a “sink” functional role, environmental conditions are often little appropriated to the maintenance of a diverse and resident fish assemblage. The migrating individuals from up and down “source” stretches are benefited by relatively constant food offer, but few diverse (mostly aquatic larvae of Chironomidae and detritus), and shelters (Typha roots).
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Rocha, Fabíola Carla da. "Ictiofauna associada à Typha angustifolia (Angiospermae) em riachos /." São José do Rio Preto : [s.n.], 2008. http://hdl.handle.net/11449/87616.
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Orientador: Lilian CasattiBanca: Katharina Eichbaum Esteves
Banca: Denise de Cerqueira Rossa Feres
Resumo: As plantas aquáticas são importantes componentes dos ecossistemas lóticos e lênticos. Como conseqüências de transformações ambientais, algumas podem se tornar dominantes, sendo que as plantas aquáticas do gênero Typha são bem sucedidas em brejos e alagados, podendo também ser encontradas em córregos e ribeirões. O presente estudo foi realizado com o objetivo de avaliar a influência de T. angustifolia para a ictiofauna em riachos. Foram estudados seis riachos na bacia do Alto Rio Turvo, Estado de São Paulo, desprovidos de vegetação ripária nativa, mas com abundância de T. angustifolia no hábitat interno e ripário. Por meio da análise de mapas de cobertura do solo, observou-se que T. angustifolia está amplamente distribuída nas zonas ripárias ao longo das drenagens estudadas. Os riachos com as maiores proporções de T. angustifolia nas zonas ripárias também apresentaram a menor riqueza de espécies e abundância de peixes. A baixa semelhança na composição e estrutura da ictiofauna entre os períodos sazonais, a grande quantidade de espécies tolerantes e o fato de que a maioria das espécies foi ou acessória ou acidental, sugerem uma dinâmica populacional do tipo "fonte e dreno" nos riachos estudados. Desta forma, os trechos livres de Typha atuam como "fontes", provendo indivíduos que, por migração, podem ocasionalmente explorar os trechos com elevada abundância de T. angustifolia. Nestes trechos, que teriam o papel funcional de "drenos", as condições ambientais são pouco apropriadas para a manutenção de uma comunidade diversa e residente de peixes. Os indivíduos dos trechos "fonte" à montante e à jusante que para ali migram se beneficiam de uma oferta relativamente constante de alimento, embora pouco variada (principalmente larvas aquáticas de Chironomidae e detritos), e abrigos (raízes de Typha).
Abstract: Aquatic plants are a major component of lenthic and lotic ecosystems. As consequences of environmental changes, some species may became dominant, being that aquatic plants of the genus Typha are a well successful group of weeds in swamps and flooded areas, but also found in headwaters and large streams. This study was made with the aim to investigate the influences of T. angustifolia on the fish assemblages in streams. A total of six streams in the Upper Rio Turvo basin, São Paulo state, without riparian vegetation but with abundance of T. angustifolia in the instream and riparian habitat, were studied. By analyzing soil coverage maps, it was registered that T. angustifolia was widespread in the riparian zones along studied drainages. Streams with the largest proportions of T. angustifolia along riparian zones were also those with lowest fish species richness and abundance. Low similarity in the composition and structure of fish fauna between seasonal periods, together with a large number of tolerant species, and the fact that most species are accessory or accidental, suggest a "source and sink" population dynamic in the studied streams. Thus, free Typha stretches play as a "source" habitat, providing individuals that, by migration, may occasionally explore stretches with large abundance of T. angustifolia. In these stretches, which play a "sink" functional role, environmental conditions are often little appropriated to the maintenance of a diverse and resident fish assemblage. The migrating individuals from up and down "source" stretches are benefited by relatively constant food offer, but few diverse (mostly aquatic larvae of Chironomidae and detritus), and shelters (Typha roots).
Mestre
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Massoni, Julien. "Phylogeny, molecular dating and floral evolution of Magnoliidae (Angiospermae)." Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-01044699.
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Deep phylogenetic relationships in the angiosperms had long been uncertain. However, by the end of the 1990s, large-scale studies contributed to the current well resolved picture of the tree of flowering plants, in which eudicots, monocots, and magnoliids are the three largest clades. Whereas monocots and eudicots have been recognized since the very first phylogenetic analyses, the monophyly of magnoliids (Canellales, Laurales, Magnoliales, and Piperales) is a more recent result. Magnoliidae, as now circumscribed, consist of 20 families and ca. 10,000 species mostly distributed in the tropics. Before the present thesis, several parts of the magnoliid tree had been well studied, but little was known about the evolutionary history of Magnoliidae as a whole. The first chapter of this thesis is a phylogenetic study conducted to clarify the relationships among families and orders of Magnoliidae. To do so, I sampled 199 species of Magnoliidae and 12 molecular markers from the three genomes and conducted phylogenetic analyses using parsimony, maximum likelihood, and Bayesian methods. The results confirm, with a greater level of support, two clades in Magnoliidae: Canellale + Piperales, and Laurales + Magnoliales. In addition, the relationships among the 20 families are generally well supported, and Lactoridaceae and Hydnoraceae are nested within Aristolochiaceae (Piperales). In the second chapter, the ages and phylogenetic positions of 10 fossils attributed to Magnoliidae were reviewed in detail. The goal of this study was to provide new reliable calibration points in order to conduct molecular dating analyses. These fossils were selected from the rich fossil record of the group because of their previous inclusion in phylogenetic analyses with extant taxa. The resulting calibration scheme provides six solid, internal minimum age constraints. The third chapter includes molecular dating analyses using the present calibration scheme and the same molecular dataset of Chapter 1. This study tends to push back in time the ages of the crown nodes of Magnoliidae (127.1-198.9 Ma), and of the four orders, Canellales (126.3-141.0 Ma), Piperales (88.2-157.7 Ma), Laurales (111.8-165.6 Ma), and Magnoliales (115.0-164.2 Ma). In the same chapter, I investigated the mode of diversification in the group. The strongly imbalanced distribution of species appears to be best explained by models of diversification with 6 to 14 diversification rate shifts. Finally, in the last chapter, I traced the evolution of 26 floral characters to reconstruct the ancestral flowers in key nodes of Magnoliidae. I used the phylogeny of Chapter 1 and an exemplar approach. Our results show that the most recent common ancestor of all Magnoliidae was a tree bearing actinomorphic, bisexual flowers with a differentiated perianth of two alternate, trimerous whorls of free perianth parts (outer and inner tepals) and probably three free stamens. This work provides key results on the evolution of Magnoliidae and raises several new questions such as the impact of geological crises on diversification of the group or the influence of pollinators and the environment on the evolution of floral morphology.
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Burmester, Anja [Verfasser]. "Beiträge zur Biologie und Anatomie ausgewählter Pflanzenarten (Angiospermae) der zentraleuropäischen Küstenflora / Anja Burmester." Kiel : Universitätsbibliothek Kiel, 2010. http://d-nb.info/1019904453/34.
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Foster, Charles Stuart Piper. "Using Phylogenomic Data to Untangle the Patterns and Timescale of Flowering Plant Evolution." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17852.
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Angiosperms are one of the most dominant groups on Earth, and have fundamentally changed global ecosystem patterns and function. Therefore, unravelling their evolutionary history is key to understanding how the world around us was formed, and how it might change in the future. In this thesis, I use genome-scale data to investigate the evolutionary patterns and timescale of angiosperms at multiple taxonomic levels, ranging from angiosperm-wide to genus-level data sets. I begin by using the largest combination of taxon and gene sampling thus far to provide a novel estimate for the timing of angiosperm origin in the Triassic period. Through a range of sensitivity analyses, I demonstrate that this estimate is robust to many important components of Bayesian molecular dating. I then explore tactics for phylogenomic dating using multiple molecular clocks. I evaluate methods for estimating the number and assignment of molecular clock models, and strategies for partitioning molecular clock models in analyses of multigene data sets. I also demonstrate the importance of critically evaluating the precision in age estimates from molecular dating analyses. Finally, I assess the utility of plastid data sets for resolving challenging phylogenetic relationships, focusing on Pimelea Banks & Sol. ex Gaertn. Through analysis of a multigene data set, sampled from many taxa, I provide an improved phylogeny for Pimelea and its close relatives. I then generate a plastome-scale data set for a representative sample of species to further refine the Pimelea phylogeny, and characterise discordant phylogenetic signals within their chloroplast genomes. The work in this thesis demonstrates the power of genome- scale data to address challenging phylogenetic questions, and the importance of critical evaluation of both methods and results. Future progress in our understanding of angiosperm evolution will depend on broader and denser taxon sampling, and the development of improved phylogenetic methods.
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Chiguer, Naïma. "Action du phoséthyl-al et du métalaxyl sur le couple phytophthora capsici-lycopersicum esculentum et de l'acide phosphoreux sur le p. Capsici in vitro : étude en microscopie électronique." Paris 11, 1985. http://www.theses.fr/1985PA112283.
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L’effet du phoséthy-Al et du métalaxyl a été étudié sur le couple Lycopersicum esculentum Phytophthora capsici, ainsi que celui de l'acide phosphoreux, métabolite actif du phoséthyl-Al sur le même parasite in vitro. L'acide phosphoreux incorporé dans le milieu de culture, à une concentration de 200 µg ml-1, permet de constater en microscopie électronique que, l'organisme fongique ne présente pas un aspect proche de la léthalité. La paroi et le plasmalemme sont affectés et particulièrement les mitochondries. Ce phénomène est également retrouvé, et de façon régulière lorsque le parasite est observé à l'intérieur des feuilles de Tomate traitées au phoséthyl-Al à une concentration de 500 µg ml-1. L'action du métalaxyl sur le P. Capsici à une concentration de 50 µg ml-1, in vivo, est plus accentuée par rapport à celle du phoséthyl-Al, car il entraîne la destruction des mitochondries et altère considérablement la structure du plasmalemme. En comparant l'action du phoséthyl-Al et du métalaxyl in vivo, on constate que ce dernier agit à des doses plus faibles en détruisant le parasite très tôt. Les deux substances permettent d’augmente la résistance des cellules hôtes par la mise en place de corps X, dont la nature est polyphénoliqueThe effects of fosethyl A1, phosphorous acid and metalaxyl were investigated among Phytophthora capsici Lycopersicum esculentum interaction. Electron microscopie observations showed some slight modification of the cell-wall, plasmalemma and mitochondria of the fungus when cultivated on 200 mg ml-1 phosphorous acid. Similar modification were observed on infected tomato leaf-lets treated with 500 mg ml-1 fosetyl-Al. The in vivo effect of metalaxyl (500 mg ml-1) on P. Capsici is more acute than the fosetyl-Al one. The fungicide affects greatly plasmalemma and mitochondria structure. Low concentrations of metalaxyl were extremely effective vivo in affecting the fungus earlier than fosetyl-Al. The two fungicides enhance host-celle resistance in producing "X bodies. Containing polyphenols
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Louis, Jean Paul. "Différenciation sexuelle chez Mercurialis annua L. (2n=16) : déterminisme nucléo-cytoplasmique, analyse biochimique et hormonale de la staminogénèse chez quelques génotypes males stériles." Orléans, 1986. http://www.theses.fr/1986ORLE0213.
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La différenciation sexuelle de Merculis annua dioïque est contrôlée par trois gènes nucléaires indépendantes A, B1, B2. A dominant associé à B1 ou B2 caractérise les mâles forts, moyens, faibles. Les femelles ont A et/ou B. La formation altérée du tissu sporogène staminal est contrôlée par trois gènes indépendants I, R1, R2 interagissant avec un facteur à trasnmission maternelle S. (I, inducteur; R1-R2, restaurateur fertilité). La restauration génétique montre que ces deux systèmes sont en interaction.
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Dejax, Jean. "Une etude palynologique dans le cretace inferieur du congo." Paris 6, 1987. http://www.theses.fr/1987PA066158.
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Il s'agit d'une etude palynologique de la serie du cretace inferieur du congo realisee a partir des sediments extraits du forage p. I. 2bis (pointe indienne). La microflore comporte des spores de pteridophytes et des pollens de gymnospermes ainsi que ceux attribues aux premieres angiospermes. Elle traduit un paleoclimat chaud, sec a aride. L'etude approfondie de la morphologie et de l'histoire evolutive des pollens des premieres angiospermes est menee
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Silveira, Carina Lima da. "Características vegetativas e reprodutivas das plantas e fatores abióticos do meio e suas relações com a alocação de biomassa floral e a seleção sexual em angiospermas." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316105.
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Orientador: Marlies SazimaTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: As plantas são organismos sésseis que estão à mercê do estresse ambiental. As flores são estruturas fundamentais na evolução das angiospermas, pois através delas ocorre a reprodução sexuada. Para isto, as flores exibem estratégias que auxiliam a planta a obter melhor sucesso reprodutivo. Animais visitam flores em busca de recursos, no entanto, ao transportar grãos de pólen entre os indivíduos da mesma espécie vegetal, atuam como mediadores no processo de seleção sexual, importante força na evolução florai. Fatores ecológicos que afetam a relação entre plantas e polínizadores podem influenciar a evolução das estratégias reprodutivas das espécies. Fatores abióticos, a distribuição espacial, o tamanho populacional e a história de vida das plantas podem modificar a abundância e a distribuição dos recursos para os polínizadores, alterando padrões de transporte de pólen, fluxo gênico e pressões seletivas responsáveis pela evolução floral. Este trabalho busca compreender a diversidade das estratégias reprodutivas em diferentes formações vegetais tropicais, a modulação por características vegetativas e reprodutivas das plantas e abióticas do meio na alocação de recursos como, também, verificar a existência de consistência biogeográfica dos padrões alométricos em relação as estratégias reprodutivas das plantas. O estudo foi realizado em áreas de vegetação tropical, sendo uma área de Floresta Atlântica, uma área de Cerrado, ambas no estado de São Paulo e uma área de Campo Rupestre, no estado de Minas Gerais, permitindo a comparação da variação da biomassa floral entre as três formações vegetais e entre angiospermas tropicais com particularidades morfológicas relacionadas às áreas de coleta e dados bibliográficos de espécies extra-tropicais. A riqueza de formas vegetais e de ambientes nas regiões tropicais atua na modulação da interação entre plantas e polínizadores, influenciando na variação da biomassa floral e nas características vegetativas e reprodutivas das espécies. As alometrias positivas e a isometria encontradas nas floras tropicais e extra-tropícats em relação ao crescimento da biomassa floral apontam para a presença e desenvolvimento de características sexuais secundarias como importantes ferramentas na permanência e sucesso da reprodução cruzada. Características vegetativas e reprodutivas influenciam na variação interespecífica da biomassa floral e que a função masculina da flor teria forte impacto na evolução das características florais, independentemente da ligação filogenética entre as angiospermas, ressaltando a necessidade de teorias que permitam uma síntese destas relações.
Abstract: Plants are sessile organisms exposed to the effects of environmental stress. The flowers are fundamental structures in the evolution of angiosperms, because through them is sexual reproduction. For this, the flowers exhibit strategies that help the plant to achieve better reproductive success. Animals visit flowers in search of resources, however, to carry pollen between individuals of the same plant species, act as mediators in the process of sexual selection, major force in floral evolution. Ecological factors affecting the relationship between plants atid pollinators may influence the evolution of reproductive strategies of species. Abiotic factors, spatial distribution, population size and life history of plants can modify the abundance and distribution of resources for pollinators by changing patterns of pollen transfer, gene flow and selective pressures responsible for floral evolution. This work seeks to understand the diversity of reproductive strategies in different tropical vegetation types, the modulated vegetative and reproductive features of plants and the abiotic environment in resource allocation as well, check for consistency biogeographical of allometric patterns in reproductive strategies in relation to plants. The study was conducted in areas of tropical vegetation, with an area of Atlantic Rain Forest, an area of Savannah, both in the state of Sao Paulo and an area of Campo Rupestre, in the state of Minas Gerais, allowing the comparison of variation among floral biomass the three vegetation types and between tropical angiosperm morphological peculiarities related to the areas of collection and bibliographic data of extra-tropical species. The richness of plant forms and environments in tropical acts in modulating the interaction between plants and pollinators, influencing the variation of biomass in the floral and vegetative and reproductive characteristics of species. The positive allometry and isometry floras found in tropical and extra-tropical growth over the floral biomass indicate the presence and development of secondary sexual characteristics as important tools in the permanence and success of cross-breeding. Vegetative and reproductive characteristics influence the interspecific variation of floral biomass and that the function of male flowers have a strong impact on the evolution of floral traits, regardless of the phylogenetic connection between the angiosperms, highlighting the need for theories that allow a synthesis of these relationships.
Doutorado
Ecologia
Doutor em Ecologia
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ROUXEL, MARIE-FRANCE. "Etude des activites ribonucleolytiques du suaeda maritima (l. ) dum. Var. Macrocarpa moq. : effets de la salinite et de la glycine betaine." Caen, 1987. http://www.theses.fr/1987CAEN2015.
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Effets du nacl in vitro et in vivo sur l'activite des proteines ribonucleolytiques, enzymes marqueurs des conditions de stress, chez une chenopodiaceae halophile. Le sel exercerait une fonction regulatrice par l'intermediaire de la glycine betaine. L'effet de cette molecule au niveau de la synthese des enzymes ribonucleolytiques est discute. Une fonction metabolique est proposee pour cette molecule "anti-stress" consideree jusqu'a present comme osmoregulatrice
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Brugidou, Christophe. "Developpement de digitalis lanata (ehrh. ) et selection pour la production d'un heteroside cardiotonique : la digoxine." Paris 6, 1987. http://www.theses.fr/1987PA066288.
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Branco, Diana Santos 1983. "Sinalização por carboidratos em cana-de-açucar e divergencia evolutiva." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317165.
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Orientadores: Michel Georges Albert Vincentz, Juliana de Maria FelixDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo:Além de fonte primária de carbono e energia para os principais tipos celulares, os açúcares produzidos pela fotossíntese adquiriram importantes funções ao longo da evolução das plantas, no controle do crescimento e desenvolvimento, do metabolismo e na resistência a estresses abióticos (osmótico, energético) e bióticos (potógenos). Os açúcares atuam como sinalizadores ativando cascatas de transdução e, desta forma, promovendo mudanças na programação da expressão gênica. Com o objetivo de entendermos como a sinalização por açúcares diversificou-se em angiospermas, iniciamos uma análise comparativa dos perfis de expressão gênica em resposta aos açúcares sacarose e glicose em plântulas da monocotiledônea Saccharum spp e da eudicotiledônea Arabidopsis thaliana. Para tanto, duas abordagens foram utilizadas. O primeiro aspecto do trabalho estabeleceu relações entre elementos de resposta rápida (resposta primária) a açúcar e acúmulo de sacarose em genótipos de cana contrastantes para teor de sacarose. Outra abordagem, mais abrangente, procurou identificar genes diferencialmente expressos em resposta à sacarose. Na primeira parte do trabalho, a análises por qRT-PCR revelaram uma clara relação entre genes envolvidos em acúmulo de sacarose em cana-de-açúcar e sinalização primária por carboidratos. A partir de 34 SAS (Sugarcane Assembled Sequence) testados envolvidos em acúmulo de sacarose em cana, 24 deles também foram responsivos à glicose e/ou sacarose, sendo que 9 deles responderam em um mesmo sentido em genótipos de cana-de-açúcar que acumulam maior quantidade de sacarose (alto Brix). Dos 24 SAS responsivos à sacarose e/ou glicose, apenas 6 deles apresentaram genes ortólogos em Arabidopsis thaliana cuja regulação por estes açúcares ocorreu de maneira similar. Dentre eles, temos o fator de transcrição IAA16, que se mostrou reprimido por sacarose e glicose, constituindo um possível gene de interação entre sinalização por açúcares e auxina. Duas SNFs quinases parálogas de cana-de-açúcar tem como ortólogo um único gene de Arabidopsis thaliana. Os três genes foram reprimidos por sacarose e glicose, sendo outra parte conservada, na via de sinalização a açúcares entre as duas espécies. Outro gene de particular interesse corresponde a uma deidrina, reprimida por sacarose e glicose em cana, assim como seu ortólogo em Arabidopsis e genótipos alto Brix, sugerindo importante papel deste gene em processos relacionados a sinalização/acúmulo de sacarose. Na segunda parte do trabalho, utilizando-se a técnica de microarranjos de cDNA a partir do chip SUCAST, encontramos 55 genes diferencialmente expressos em resposta à sacarose. Destes, apenas 3 apresentaram genes ortólogos de Arabidopsis regulados por açúcar num mesmo sentido que em cana, correspondentes a duas proteínas quinases e a um gene pseudo-response-regulator. Este estudo preliminar identificou genes conservados da sinalização por açúcares em angiospermas que representam possíveis nós importantes das redes de controle relacionadas a carboidratos. O estabelecimento de um possível envolvimento de alguns destes genes no controle da capacidade de acumular mais sacarose no colmo da cana, abriu novas perspectivas na análise molecular desta importante característica. Estudos mais abrangentes são necessários para melhorar os conhecimentos sobre o grau de diversificação da sinalização por açúcares em angiospermas e os valores adaptativos associados.
Abstract: Besides act as carbon primary source in the major types of cells, sugars produced by photosynthesis acquired important functions in the course of plant's evolution like controlling growth, development, and metabolism and acting in resistance to abiotic and biotic stresses like osmotic, energetic and response to pathogens. Sugars can be signals that active signal transduction pathways to change genes expression programs. In order to access the diversification of sugar pathway signaling in angiosperms we conduct comparative analysis of the gene expression in response to sucrose and glucose in seedlings of the monocot Saccharum sp. and the eudicot Arabidopsis thaliana. We also aimed to access the possible correlation between genes related to sucrose storage in sugar-cane and genes related to primary sugar responses. Another aim was to identify deferentially expressed genes in sucrose response. A clearly relation between genes related to sucrose storage in sugar-cane and quickly primary response to sugars was obtained by qRT-PCR analysis. We tested 34 SAS (Sugar Assembled Sequence) related to sucrose storage in sugar-cane and we found that 24 of them were responsive to glucose and/or sucrose. Nine genes showed the same expression pattern (induction or repression) in response to sugar as seen in high Brix genotypes. Six, of this 24 genes, have Arabidopsis orthologues regulated in the same direction (induced or repressed). One is an IAA16 transcription factor that is repressed by both, glucose and sucrose, and may play a role in an integrative pathway of sugar and auxin responses. We also find two SNFs kinases (paralogues) related to a single Arabidopsis ortholog showing the repression response. Another interesting gene is a dehydrin that was repressed in response to sucrose and glucose in sugar-cane and Arabidopsis (its ortholog) and in the high Brix sugar-cane genotypes. It suggests an important role for this dehydrin in processes related to sucrose signaling and storage. In the second part of this work, the sugar-cane cDNA microarray chip, called SUCAST, allow us to identify 55 deferentially expressed in response to sucrose. Only three of these genes have orthologues regulated in same way in sugar-cane and Arabidopsis. These genes correspond to two protein-kinase and a pseudo-response regulator. This preliminary approach leads us to identify conserved genes in sugar signaling among angiosperms that possibly represents important nodes in the regulatory networks in response to sugars. Establishing the involvement of some of these genes in the ability of sucrose storage in sugar-cane's culm will lead us to new perspectives in the molecular basis of this characteristic. More specific works are also needed to improve the knowledge about the real degree of evolutive diversification in sugar signaling among angiosperms and associated genetic fitness.
Mestrado
Genetica Vegetal e Melhoramento
Mestre em Genética e Biologia Molecular
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Martins, Aline Cristina. "Abelhas coletoras de óleo e suas interações com as flores de Plantaginaceae produtoras de óleo floral." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-23042010-154006/.
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Os óleos florais são os recursos alternativos ao pólen e néctar oferecidos por onze famílias de angiospermas às abelhas coletoras de óleo. A produção deste recurso surgiu ao menos 28 vezes e a coleta destes, em cinco linhagens distintas entre as abelhas. Na região Neotropical, Malpighiaceae é a família mais diversa e melhor conhecida em termos de seu sistema de polinização e relação com abelhas coletoras de óleo. Plantaginaceae é conhecida por alguns trabalhos, focados principalmente em Angelonia e Monttea. No presente estudo, são apresentadas as relações entre abelhas coletoras de óleo e flores de Plantaginaceae (cinco espécies de Angelonia e uma de Basistemon), com especial atenção aos aspectos morfológicos de ambos, aspectos comportamentais das abelhas durante a coleta e a sobreposição geográfica entre os parceiros deste mutualismo. Este trabalho apresenta pela primeira vez dados dos visitantes de três espécies: A. eriostachys, A. goyazensis e Basistemon silvaticus; além de dados inéditos sobre espécies já estudadas: A. cornigera, A. integerrima e A. salicariifolia. Foi observado que as estruturas especializadas presentes no labelo de todas as espécies estudadas de Angelonia estão associadas à imposição da postura correta do visitante e sua fixação na flor. As flores de Basistemon são mais simples neste sentido e apresentam apenas um discreto calo mediano. Apesar da morfologia destas estruturas diferirem consideravelmente entre as espécies, é possível estabelecer relações de origem entre elas. A assembléia de visitantes das flores de Angelonia e Basistemon variou entre três a dezoito espécies. Estas espécies foram consideradas polinizadoras ou visitantes ilegítimos. As abelhas do gênero Centris foram consideradas as principais polinizadoras das plantas estudadas, porém, espécies de Tapinotaspidini, em especial o gênero Caenonomada, também detêm esse papel. As abelhas que coletam óleo também coletam pólen, com exceção dos gêneros Centris, Caenonomada e Tapinotaspis, que coletam apenas óleo. O comportamento adequado dos polinizadores de Angelonia e Basistemon, imposto pela morfologia floral, implica na coleta do óleo com as pernas anteriores e o contato com os órgãos férteis na fronte ou mesoscuto em flores com corola mais profunda. Algumas espécies estão morfologicamente adaptadas a coleta nestas flores, como exemplo, as abelhas Centris grupo hyptidis, que possuem aparatos coletores divergentes de todo o padrão apresentado pelo gênero. Quanto à distribuição destas plantas e de seus potenciais polinizadores, em alguns casos, há grande sobreposição e os potenciais polinizadores podem ou não ser especialistas nestas fontes de óleo. Os casos de baixa congruência geográfica mostram que muitos destes potenciais polinizadores não dependem das fontes de óleo de Angelonia e Basistemon.Floral oils are alternative flower reward to pollen and nectar that are offered by eleven families of angiosperms to oil-collecting bees. The production of this resource appeared at least 28 times, and its collection has been observed in five different lineages of bees. In the Neotropical Region, Malpighiaceae is the most diverse and best known family concerning to the pollination system and the interactions with oil-collecting bees. Plantaginaceae is well known due to some studies mostly on Angelonia and Monttea. In this study, the relationship between the oil-collecting bees and the Plantaginaceae flowers (five species of Angelonia and one of Basistemon) is presented, being given special attention to the morphological aspects of both, the bees behavior during the oil collection and the geographical overlap between the partners of this mutualism. This work presents for the first time the visitors of three species (A. eriostachys, A. goyazensis and Basistemon silvaticus), as well as new data on already studied species (A. cornigera, A. integerrima and A. salicariifolia). It was recorded that the specialized structures that are found on the lip (labellum) of all the known species of Angelonia are associated to the imposition of the correct posture of the visitor and their fixation on the flower. The Basistemon flowers are, in this way, less complex and they present only a discrete median callus. Although the morphology of these structures differ considerably among species, it is possible to establish relationships between their origins. The assemblage of visitors of the flowers of Angelonia and Basistemon varied from three to eighteen species. These species were considered pollinators or illegitimate visitors of the studied species. The bees of the genus Centris were considered the main pollinators of these plants; however species of Tapinotaspidini also play this role. These bees collect oil and pollen, in most species, having as exceptions the genera Centris, Caenonomada e Tapinotaspis that collect only oil. The correct behavior of the visitors of Angelonia and Basistemon flowers, imposed by the floral morphology, results the collection of oil with the forelegs and the contact of their fertile organs with their anterior head or dorsal thorax (in flowers with deep corolla). Some species are morphologically adapted to sample in these flowers, for example, the Centris bees group hyptidis, that have collecting apparatus that diverge from the pattern found in the genera. In respect to the distribution of these plants and their potential pollinators, in some cases, there is a large overlap and the potential pollinators may or may not be specialists in these oil sources. The cases of low geographical congruency show that many of these potential pollinators do not depend only on the oil sources of Angelonia and Basistemon.
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Brunel, Jean-Frédéric. "Sur le genre phyllanthus l. Et quelques genres voisins de la tribu des phyllantheae dumort. (euphorbiaceae, phyllanthoideae) en afrique intertropicale et a madagascar." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13237.
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Boisseau-Tamoudi, Cécile. "Localisation et biosynthese des isolectines des graines de lathyrus ochrus (l. ) dc." Toulouse 3, 1987. http://www.theses.fr/1987TOU30091.
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Fagundes, Paula Braga. "Um lugar ao sol : a influência do fator histórico sobre o nicho de luz e respostas ecofisiológicas de plantas com semente da floresta ombrófila mista." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/90470.
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Em ambientes florestais, a luz é o recurso que com mais frequência limita o crescimento, a sobrevivência e a reprodução em plantas. Assim, a variação na disponibilidade de luz no sub-bosque influencia a composição local de espécies lenhosas, que se segregam em diferentes nichos de luz de acordo com suas preferências e tolerâncias, conferidas através de suas adaptações e plasticidade fenotípica. Os atributos das espécies atuais, além de serem adaptados ao ambiente onde vivem, são um legado de seus ancestrais, motivo pelo qual espécies mais próximas filogeneticamente, com frequência compartilham atributos semelhantes e, por consequência, ocupam nichos similares, padrão conhecido como conservação filogenética. Estudos recentes mostram que atributos funcionais relacionados à captação de luz teriam se diversificado através de diferentes grupos filogenéticos, conferindo a estes capacidades distintas para a conquista de novos ambientes de luz. Nosso trabalho teve como objetivo detectar a presença de padrões filogenéticos na distribuição e nas respostas ecofisiológicas de oito espécies lenhosas co-ocorrentes e de seus respectivos clados em um sub-bosque florestal, a partir da comparação do nicho de luz e do desempenho de plantas juvenis em resposta ao gradiente luminoso existente. Assim nossas hipóteses são de que 1) as espécies filogeneticamente próximas tem maior semelhança em estratégias adaptativas do que espécies filogeneticamente distantes; 2) a amplitude de nicho e 3) a plasticidade de atributos em resposta à luz aumentam em clados mais derivados. Os resultados apresentados aqui mostraram uma maior similaridade entre as espécies mais relacionadas do que entre aquelas que são filogeneticamente distantes, sugerindo conservação filogenética do nicho. Quanto à amplitude de nicho, também há uma influência filogenética, porém, contrário ao esperado, os clados mais antigos apresentaram um nicho mais amplo. Para a plasticidade dos atributos os resultados aqui apresentados mostram que não há padrões filogenéticos na plasticidade das respostas de espécies e clados estudados, sugerindo o efeito de outros fatores sobre a plasticidade das plantas, como efeitos ontogenéticos ou estresse ambiental.In forest environments, light is the resource that most often limits the growth, survival and reproduction in plants. Thus, the variation in light availability, regarded as one of the most important resources for woody plants in the understory, results in differences in species composition, which segregate in different light niches according to their preferences and tolerances, conferred by their adaptations and phenotypic plasticity. Extant plant traits are not only adapted to the present environment, they are also a legacy from their ancestors and, for that reason, phylogenetically related species often share similar attributes and consequently occupy similar niches, pattern known as phylogenetic conservatism. Recent studies show that functional traits related to the capture of this resource have diversified across different phylogenetic groups, giving them distinct abilities to occupy new light environments. The present study aimed to detect the presence of phylogenetic patterns in species distribution along a light gradient and in ecophysiological responses of eight co-occurring woody species and their respective clades in a forest understory. This was accomplished by comparing the light niche of juvenile plants in response to the existing light gradient, as well as their physiological plasticity in response to understory light variations. We hypothesized that (1) phylogenetic related species have greater similarity of adaptive strategies, and consequently of their niche, than more distantly related ones; and that (2) the niche breadth is wider and (3) traits plasticity is greater in more recent than in more basal clades. The results presented here showed that there is a greater niche similarity between closely related species than between those that are phylogenetically distant, suggesting niche conservatism. Regarding to niche amplitude, there is also a phylogenetic influence but, contrary to our expectations, the older clades showed a greater niche breadth. For plasticity of selected plant traits, results showed no phylogenetic pattern for the studied species and clades, suggesting that other factors act on the phenotypic plasticity of plants, such as ontogenetic effects and/or environmental stress.
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Rötig, Agnès. "Composition polypeptidique des mitochondries vegetales et essai de caracterisation des nadh deshydrogenases." Paris 6, 1987. http://www.theses.fr/1987PA066062.
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Cochet, Thierry. "Caracterisation et expression de l'etat de sensibilite a l'acide gibberellique des cellules apicales de silene armeria l. , race s : :(2-1) (caryophyllacees)." Paris 6, 1988. http://www.theses.fr/1988PA066155.
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SCHMIT, BENNER ANNE-CATHERINE. "Le cytosquelette tubuline / f-actine de cellules de plantes superieures : identification, dynamique et interactions in vivo, en interphase et en mitose." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13123.
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Sadik, Amina. "Contribution a l'etude d'une viscacee hemiparasite epiphyte : arceuthobium oxycedri (d. c.) m. bieb. : organisation et ultrastructure du systeme endophytique, etude de quelques aspects de la physiologie du parasite et de ses relations avec l'hote." Nantes, 1988. http://www.theses.fr/1988NANT2029.
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Lashermes, Philippe. "Gynogenese et androgenese in vivo chez le mais (zea mays l. ) : etudes genetique et physiologique, utilisation en selection." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21058.
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Chedhomme, Francine. "Caracteristiques electriques des vesicules de tonoplaste en suspension dans le jus de kiwi (actinidia chinensis p. )." Paris 7, 1987. http://www.theses.fr/1987PA077025.
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Le jus cellulaire du kiwi (actinidia chinensis) est particulierement riche en vesicules membranaires, comparables a des protoplastes ou des vacuoles libres, obtenues sans traitements enzymatique ni chimique. En realite, ces structures sont essentiellement issues de la rupture puis de la revesiculisation du tonoplaste limitant les travees cytoplasmiques des cellules. La fragmentation des vacuoles, in situ, conduit le tonoplaste a se refermer aussi bien sur le suc vacuolaire que sur le cytoplasme des travees, ce qui implique une orientation differente de sa face interne, vis-a-vis du milieu exterieur. L'approche electrophysiologique chez les vesicules ou le tonoplaste garde son orientation initiale, met en evidence leur polarisation positive, a l'instar des protoplastes et des vacuoles isolees. Le changement de l'orientation du tonoplaste vis-a-vis du milieu inverse le gradient electrique transtonoplastique qui devient negatif. Les caracteristiques thermodynamiques du transport de k**(+) et h**(+) a travers le tonoplaste (inverse ou non) des vesicules des fruits conserves (variete hayward) montrent que les potentiels mesures (negatifs ou positifs) sont essentiellement d'origine diffusive. Neanmoins, chez les vesicules cytoplasmiques provenant des fruits frais (variete deliciosa), une faible composante electrogene associee au fonctionnement de la pompe a h**(+) (mg-atpase tonoplastique) n'est pas exclue
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Pavard-Ohanessian, Jacqueline. "Contribution à l'étude de la stéréochimie des chaines glycaniques de glycoprotéines et à l'étude de leurs interactions avec la lectine d'arachide spécifique des substrats d-galactosyles terminaux." Paris 13, 1986. http://www.theses.fr/1986PA132005.
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De, Jaegher Geert. "La thigmomorphogenese de la bryone : lignification et metabolisme de l'ethylene." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21029.
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Caracterisation des repercussions d'un stimulus mecanique sur le metabolisme phenolique et evaluation de l'impact des effets observes sur le ralentissement de croissance des entre-noeuds. Precision sur le metabolisme de l'ethylene et le mode d'intervention de ce regulateur de croissance dans la thigmomorphogenese
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Ontoria, Gómez Yaiza. "Seagrass responses to climate change: effects of warming and the interaction with local stressors = Respuestas de las angiospermas marinas al cambio climático: efectos del calentamiento y la interacción con estresores locales." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/669000.
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Coastal ecosystems are highly threatened worldwide by multiple anthropogenic stressors that act at a range of spatial scales, from local to the global, and adversely affect their ecological functions and associated biodiversity. Global warming is one of the most pervasive stressors, and the assessment of how the species (or other levels of biological organization) react to it is an urgent need in a rapidly warming world. Moreover, thermal stress rarely acts in isolation from other stressors. The potential synergies among global warming and local stressors is of particular concern in what it regards foundation species, such as the case of seagrasses, due to their crucial role in maintaining the structure and function of coastal ecosystems. The main objective of this PhD thesis is to improve the knowledge of how warming alone and in combination with different local factors can affect seagrasses. This research has been conducted based upon mesocosm experiments submitted to different temperatures (and, in some cases, to other agents), and plants responses measured from biochemical to population levels. The results obtained are considered an approach to what may occur in the real world, always acknowledging the limitations of our methodology.
Chapter 1 revealed different tolerance to warming among the two main Mediterranean seagrass species, Cymodocea nodosa and Posidonia oceanica. C. nodosa tolerates temperature increases much better than P. oceanica probably due to its life story (opportunistic), habitat (from confined waters to the open sea) and biogeographical affinity (tropical and subtropical). This will potentially cause changes in the distribution area of these two species in the Mediterranean under a future scenario of warming.
As shown in Chapter 2, an increase in nutrient concentration in water does not modify the response of C. nodosa to warming. However, the increase of organic matter in sediment clearly worsens, synergistically in some plant traits, the effects of warming, entailing a hazardous combination for plant survival. P. oceanica, in turn, is severely affected by conditions of high nutrient content and high temperatures (Chapter 3), again displaying synergistic effects, and confirming not only a thermal sensitivity in this species greater than in C. nodosa, but also a greater vulnerability to the exacerbation of thermal effects by other local stressors.
Finally, the interactive effects of warming and salinity (Chapter 4) in an estuarine seagrass species, Halophila ovalis, in southwestern Australia resulted beneficial for plant survival, as the negative effect of warming was buffered by concomitant salinity increases.
Overall, this research highlights the complexity of global warming effects in at least two aspects. Firstly, the multiplicity of biological levels at which those effects act and, secondly, the importance of studying not only isolated effects of temperature increases but also their joint effect with other stressors. Advances in these two directions will yield more realistic predictions concerning global warming and seagrass ecosystems and help to develop management policies to protect seagrass ecosystems in a changing world.
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Mosiniak-Bessoles, Michèle. "Contribution a l'etude des oscillations spontanees de l'assemblage cellulosique dans les parois des cellules vegetales." Paris 6, 1987. http://www.theses.fr/1987PA066189.
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Un systeme oscillatoire tres caracteristique des parois cellulaires des cellules vegetales est constitue par l'assemblage helicoidal. Par des recherches methodologiques de demasquage et de dissection des edifices microfibrillaires, par une analyse stereoscopique et par une modelisation des variations dans l'espace et dans le temps, on etablit la dynamique, la gamme et les modalites d'adaptation du systeme en fonction de la differenciation cellulaire afin de mieux comprendre la morphogenese parietale
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NIEBLA, HERNANDEZ MERCEDES. "Initiation foliaire et interaction auxine-acide triiodobenzoique chez lycopersicum esculentum mill (solanacees)." Paris 6, 1987. http://www.theses.fr/1987PA066556.
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Kouadio, Kouassi N'guettia Venance. "Modification de croissance et remaniements dans la fraction azotée chez de jeunes plants de chêne (quercus robur L. ) soumis à un dessèchement : Effets d'un apport exogène de glycine bétaine." Nancy 1, 1986. http://www.theses.fr/1986NAN10074.
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Analyse des conséquences de stress hydriques d'intensité variable au niveau de la croissance longitudinale, organogénèse, croissance pondérale et de la fraction azotée (azote total, azote soluble, acides aminés + amides libres, proline et composés à groupement onium méthyle). Ensuite, le comportement de plants stressés ou cultivés en présence de glycine bétaine ou de glycine est comparé au niveau du potentiel trophique du substrat, de sa pression osmotique et d'une action anti-stress
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CANDELIER, PASCALE. "Etude comparee des effets du froid et de l'ethanol sur la dormance de tubercules de topinambour (helianthus tuberosus l. ) : evolution de quelques parametres biochimiques." Clermont-Ferrand 2, 1989. http://www.theses.fr/1989CLF21159.
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Un traitement de 24 h par des vapeurs d'ethanol produit, dans le parenchyme des tubercules dormants: une augmentation de la fluidite lipidique du plasmalemme, une elevation de la teneur en atp, un abaissement simultane des ph cytoplasmiques et vacuolaires, une diminution des syntheses proteiques et une modification qualitative des proteines synthetisees. Ces effets sont provisoires et sont a rapprocher de ceux qui se produisent lors de la veritable levee de dormance
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Conchou, Odile. "Dynamique et fonctionnement d'une population pionniere de phalaris arundinacea l. , a l'interface terre-eau dans la moyenne vallee de la garonne." Toulouse 3, 1987. http://www.theses.fr/1987TOU30057.
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Cette espece constitue le premier stade de la colonisation vegetale en bordure de riviere, sur les milieux de la colonisation vegetale en bordure de riviere, sur les milieux instables de la zone de remaniement affectee par les crues. Les conditions d'engorgement affectent mais ne bloquent pas le developpement des plantuls et cette tolerance est une preuve de la plasticite ecologique de l'espece. On souligne la possibilite d'une utilisation pour la resine en vegetation des ouvrages hydroelectriques
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Canut, Hervé. "Proteolyse intracellulaire chez les vegetaux superieurs : role du compartiment vacuolaire." Toulouse 3, 1986. http://www.theses.fr/1986TOU30030.
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Resultats obtenus chez melilotus alba et acer pseudoplatanus. Methodologie permettant l'obtention de vacuoles isolees et d'une fraction cytosolique purifiee. Identification, caracterisation et localisation dans la cellule, des systemes proteolytiques responsables de la degradation des proteines. Specificite des proteases vis-a-vis de differents substrats proteiques. Definition d'un modele d'etude permettant une approche in vivo du phenomene afin d'apprecier le niveau d'intervention de la vacuole dans les processus proteolytiques
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Bouya, Driss. "Etude de l'absorption du saccharose par les suçoirs d'une phanérogame parasite : Cuscuta reflexa Roxb." Grenoble 1, 1986. http://www.theses.fr/1986GRE10085.
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Nespoulous, Claude. "Caractérisation de la prise d'oxygène à la lumière chez deux végétaux modèles : influence d'un régulateur de croissance sur les échanges gazeux." Aix-Marseille 2, 1986. http://www.theses.fr/1986AIX22047.
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Fanton, Jean Carlo Mari 1983. "Reconstruindo as florestas tropicais úmidas do eoceno-oligoceno do sudeste do Brasil (Bacias de Fonseca e Gandarela, Minas Gerais) com folhas de fabaceae, myrtaceae e outras angiospermas : origens da Mata Atlântica." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287244.
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Orientador: Fresia Soledad Ricardi Tores BrancoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências
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Resumo: Folhas isoladas de angiospermas preservadas em depósitos fluvio-lacustres das bacias de Fonseca e Gandarela foram analisadas visando reconstruir o paleoambiente. Angiospermas são bons indicadores climáticos, pois a distribuição de suas espécies no espaço/tempo e influenciada pelo clima. Localizadas no centro-sul de Minas Gerais, as bacias de Fonseca e Gandarela são grabens encravados no embasamento Pré-Cambriano, depositados nos intervalos Neoeoceno-Eoligoceno e Neoeoceno- Eomioceno (respectivamente), segundo dados paleológicos. Como métodos, alem da morfotipificação, características arquiteturais informativas permitiram identificações taxonômicas com base apenas em folhas. Para estimar as paleotemperaturas, aplicou-se a Analise da Margem Foliar (LMA) utilizando a relação entre a proporção de espécies arbóreas "dicotiledôneas" com margens lisas (pE) e a media anual de temperatura (MAT). Antes, a habilidade de modelos sul-americanos foi testada em florestas atlânticas do sudeste. Devido à pEs altas (0,78-0,87), as temperaturas dos locais quentes-baixos (MAT ? 23°C) foram estimadas corretamente, mas o erro foi maior nos locais frios-elevados (MAT ? 22°C, 610-890 m). Mesmo que linhagens obrigatoriamente lisas estiveram super-representadas tanto nos locais quentes quanto frios (em media 38% das espécies/local), o desenvolvimento de terras altas desde o Neocretaceo e Cenozóico no sudeste inviabiliza hipóteses de tempo insuficiente para a evolução de margens denteadas nas angiospermas adaptadas a altitude. Para Fonseca (40 morfotipos) e Gandarela (20) foram obtidas pEs tão altas (0,90 e 0,95) quanto às de florestas equatoriais amazônicas atuais. MATs ? 24,7°C foram reconstruídas pela maioria dos modelos (em media ?27-28°C), faixa megatermica hoje registrada principalmente em terras-baixas do norte e nordeste do Brasil. Mais da metade dos 25 morfotipos aqui descritos foram identificados em famílias tropicais, como Lauraceae (FS06, GR03 e GR09), Fabaceae (FS01-03, FS05, FS09 e GR08), Combretaceae (FS08) e Myrtaceae (FS11-13 e GR02). Todas são linhagens com uma longa historia evolutiva (no mínimo desde o Paleoceno-Eoceno) no norte (Fabaceae e Lauraceae) e no sul (Myrtaceae) da America do Sul, expondo um antigo legado de tropical idade e influencia floristica mista (boreal-laurasiana e austral-antartica). Hoje no sudeste, tais famílias controlam boa parte dos recursos ecológicos na Mata Atlântica e provavelmente já o faziam nas florestas do Neopaleogeno. Devido à composição e certas condições ambientais compartilhadas, as florestas ombrofilas do compartimento sul da Mata Atlântica (inclusive a Floresta Ombrofila Mista, FOM) são analogias modernas parcialmente comparáveis com Fonseca e Gandarela: temperaturas e pluviosidade elevadas mantendo um dossel sempre-verde e multiestratificado, dominado por angiospermas (Myrtaceae, Lauraceae e Fabaceae) e coníferas austrais (Podocarpaceae e Araucariaceae). Confirmam a reconstrução de florestas tropicais úmidas: (1) o conjunto fisionômico da Formação Fonseca (onde 40- 65% dos morfotipos avaliados têm ápice acuminado, 80-90% margens lisas e 50% notofilo-mesofilos) e (2) a presença de linhagens que demandam umidade e intolerantes ao frio, como podocarpaceas dacrydioides (Dacrydiumites) e mirtaceas como FS13 (identificado em Curitiba), exibindo uma folha acuminada 2× maior que da atual C. prismática, espécie endêmica da FOM. O cenário reconstruído se ajusta aos níveis superiores de CO2 atmosférico, maior zona tropical e invernos relativamente brandos do final do Paleogeno
Abstract: Isolated fossil angiosperm leaves preserved in fluvial-lacustrine deposits from the Fonseca and Gandarela basins were analyzed to reconstruct the paleoenvironment. Angiosperms are good climatic indicators since the species distribution in space/time is influenced by the climate. Located in central-southern part of the State of Minas Gerais, the Fonseca and Gandarela basins are grabens embedded in the Precambrian basement, deposited during the Late Eocene-Early Oligocene interval, according to palynological data. As methods, informative architecture characteristics allowed taxonomic identifications solely on the basis of leaves. To estimate paleotemperatures, the Leaf Margin Analysis (LMA) was applied, based on the relationship between the proportion of untoothed woody "dicot" species (pE) and mean annual temperature (MAT). Before, the ability of South American models was tested on modern sites of Atlantic forests from southeastern Brazil. Because of high pEs (0,78-0,87), temperatures of the low-elevation sites (MAT ? 23°C) were predicted accurately, but the error was greater in the high-elevation ones (MAT ? 22°C, 610-890 m). Although obligate untoothed lineages were richly represented in low and high-temperature sites (in average 38% of the species per site), the development of highlands in southeastern Brazil since the Late Cretaceous and Cenozoic invalidate hypotheses about an insufficient time to evolve teeth in angiosperms adapted to high-elevations. Both fossil floras Fonseca (40 morphotypes) and Gandarela (20) showed pEs (0,90 and 0,95) so high as observed in Amazonian equatorial rainforests. MATs ? 24,7°C were yielded for the majority of the models (in average ?27-28°C), isotherm today registered mainly in lowlands from northern Brazil. Over half of the morphotypes described were identified in families essentially tropical, such as Lauraceae (FS06, GR03 and GR09), Fabaceae (FS01-03, FS05, FS09 and GR08), Combretaceae (FS08) and Myrtaceae (FS11-13 and GR02). All these lineages have a long evolutionary history (since at least the Paleocene- Eocene) in the north (Fabaceae and Lauraceae) and south (Myrtaceae) of South America, revealing an antique legacy of tropicality and mixed floristic influence from boreal-laurasian and austral-Antarctic regions. Today, such families have controlled a major portion of the ecological resources in the Atlantic forests from southeastern Brazil probably retaining dominance since the Paleogene. Similar composition and some environmental aspects suggest that the rainforests from the southern Atlantic block (including Araucaria rainforest) are the closest living analogues to the Fonseca and Gandarela extinct vegetation: high temperatures and heavy rainfall sustaining an evergreen and multilayered canopy dominated by angiosperms (Myrtaceae, Lauraceae and Fabaceae) and austral conifers (Podocarpaceae and Araucariaceae). Additional evidence supporting the tropical rainforest hypothesis is: (1) the Fonseca Formation leaf physiognomy (40-65% of the morphotypes evaluated have drip tips, 80-90% untoothed margins and 50% are notophyll-mesophyll), and (2) the presence of water-demanding and coldintolerant lineages, such as dacrydioid podocarps (Dacrydiumites) and the Myrtaceae morphotype FS13 (identified as Curitiba), which bears an acuminate leaf 2× longer than the extant C. prismatica. The paleoenvironment reconstructed agree with the higher atmospheric CO2 levels, the wider Tropical zone and the relatively mild winters during the Late Paleogene
Doutorado
Geologia e Recursos Naturais
Doutor em Ciências
35
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Ghomari, Fouzia. "Photorégulation de la glycéraldéhyde 3-phosphate deshydrogénase à NADP de radis, sous rouge lointain continu." Rouen, 1987. http://www.theses.fr/1987ROUES016.
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Tercé-Laforgue, Thérèse. "Sur le polymorphisme et la biosynthese des gliadines de ble tendre (triticum aestivum l. Variete capelle-desprez)." Paris 6, 1986. http://www.theses.fr/1986PA066579.
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Petel, Gilles. "Etude comparee chez le tubercule dormant et non dormant de topinambour (helianthus tuberosus l. ) de l'atpase et du systeme transporteur d'electrons lies au plasmalemme de la cellule parenchymateuse." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21023.
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Mise en evidence des activites enzymatiques generatrices de potentiel membranaire; etude de leur potentialite de fonctionnement dans le materiel dormant et non dormant puis comparaison des potentialites existantes dans les 2 types de materiels. L'etude des proprietes de l'atpase (difference de lambda m) constitue un argument en faveur d'un remaniement membranaire au cours de la levee de dormance. Etablissement de nouvelles correlations intercellulaires a courte distance conferant de nouvelles proprietes morphogenetiques aux bourgeons
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Zhou, Dao Xiu. "Organisation et expression de gènes chloroplastiques et nucléaires codant pour des protéines ribosomiques du chloroplaste d'épinard." Grenoble 1, 1988. http://www.theses.fr/1988GRE10113.
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SCHMITZ, BOURGEOIS MONIQUE. "Isolement et structure d'un pseudodipetide (gamma-l-glutamyl-l-aspartique) extrait du datura stramonium qui perturbe la retention mnesique chez la souris." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13094.
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Belle, Rogerio. "Recherches sur l'origine de l'hétérogénéité du poids et des propriétés germinatives de graines de colza (brassica napus l. Var. Oleifera metzg)." Paris 6, 1986. http://www.theses.fr/1986PA066384.
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L'hétérogénéité des propriétés morphologiques, physiques et germinatives de graines de colza (Brassica napus l. ) a été étudiée au cours de leur développement selon la position sur la plante mère, l'état de récolte associe à la durée de la conservation. Nous avons aussi étudié le vieillissement des semences et leur respiration durant la germination. Des comportements corrélatifs ont été mis en évidence pour des plantes isolées, en peuplement ou traumatisées. Une double modalité de la courbe de dégagement de gaz carbonique a été observée lorsque les semences vieillies sont mises à germer.
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Shoar-Ghafari, Almas. "Caractères cytologiques des grains protéiques et des globoïdes, dans les graines en vie latente d'Helianthus annuus l. (composées) et d'Alisma plantago l. (alismacées)." Paris 6, 1986. http://www.theses.fr/1986PA066598.
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Kieffer, Martine Suzanne Josée. "Les angiospermes herbacées toxiques d'Alsace." Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR1M224.
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Godet, Xavier. "Biologie du colchique (colchicum autumnale l. ) : multiplication vegetative par voie traditionnelle et in vitro." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2D189.
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Examen des cycles biologiques de la plante adulte et de la plante juvenile: les exigences thermiques, les potentialites du bourgeon vegetatif accessoire, variabilite individuelle pour la production de graines et d'alcaloides. Une methode de multiplication vegetative est recherchee: en pepiniere ou in vitro, possibilite de fragmenter les cornus; caulogenese in vitro. La possibilite d'une biosynthese d'alcaloides par des cellules de colchique cultivees in vitro est evoquee
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MASSON, PHILIPPE. "Contribution a la valorisation des proteines de reserve du ble tendre (triticum aestivum) : isolement et caracterisation partielle de peptides issus de l'hydrolyse enzymatique menagee de gliadines totales et purifiees." Nantes, 1988. http://www.theses.fr/1988NANT2023.
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Mussigmann, Caroline. "Aspects de l'expression genomique en relation avec les potentialites morphogenetiques de tubercules de topinambour (helianthus tuberosus l. )." Clermont-Ferrand 2, 1988. http://www.theses.fr/1988CLF21099.
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Chen, Hsu-Ching. "Etude des genes de trna mitochondriaux d'arabidopsis thaliana." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13131.
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Trois genes de trna**(tyr) ont ete identifies et sequencies. L'analyse de leur sequence nucleotidique a montre que l'un des genes coderait pour un trna**(tyr) fonctionnel (trna**(tyr-2)) et les deux autres seraient des pseudogenes. Le trna**(tyr-2) derive probablement d'un gene trna**(phe) par des evenements de recombinaison genetique. La sequence nucleotidique de deux genes de trna mitochondriaux codant pour un trna**(ser) et un trna**(glu) respectivement a ete determinee. Les deux genes ont une homologie de 99% avec leurs homologues mitochondriaux d'autres plantes
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Sagliocco, Francis. "Populations d'ARNs poly (A+) cytoplasmiques spécifiques de l'organogénèse reproductrice chez Mercurialis annua L. (2n=16) (Hybridations homologues et hétérologues) : relations avec les phytohormones." Orléans, 1986. http://www.theses.fr/1986ORLE0407.
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MARTINEZ, DE LA CRUZ ISABEL 233982, and DE LA CRUZ ISABEL MARTINEZ. "Diversidad de angiospermas en el Estado de México." Tesis de doctorado, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/106134.
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En México, las angiospermas o plantas con flores son el grupo vegetal más diverso. El estado de México ocupa el noveno sitio entre las diez entidades con mayor riqueza florística en la República Mexicana. Sin embargo, es la entidad con mayor número de habitantes, uno de los principales productores agrícolas, la segunda zona industrial más importante y registra la mayor cantidad de incendios forestales. Lo anterior pone de manifiesto el riesgo en el que se encuentra el patrimonio vegetal y marca la necesidad de contar con información sobre la riqueza y distribución de las angiospermas para evaluar áreas desconocidas botánicamente o que carecen de registros suficientes, determinar centros de riqueza biológica, establecer prioridades de conservación, elaborar planes municipales de desarrollo urbano, ordenamientos territoriales y ecológicos, y con ello contribuir al desarrollo sustentable del estado de México. El objetivo fue analizar el conocimiento actual de la riqueza y distribución de las angiospermas en el estado de México, con base en la literatura, tanto publicada como no publicada. Se realizó una revisión exhaustiva de documentos florístico-taxonómicos que reportan angiospermas en el estado de México; se integró una base de datos de las plantas con flores que permitió elaborar mapas de ubicación geográfica y área de estudio de los inventarios, riqueza de angiospermas en las provincias florísticas, riqueza conocida en los municipios de la entidad y riqueza estimada de angiospermas. La similitud florística entre inventarios y municipios comprendidos en las provincias florísticas se expresó mediante el índice de Sørensen-Dice. La lista integró 169 familias, 1103 géneros y 3924 especies. Alrededor de 15% del total de especies corresponden a Asteraceae, 10% a Fabaceae, 9% a Poaceae y 6% a Orchidaceae. Muhlenbergia, Salvia, Ipomoea, Euphorbia y Ageratina poseen la mayor diversidad. La distribución de los sitios de exploración botánica no es uniforme; la región sur-suroeste ha sido más explorada, las zonas montañosas son pobremente recolectadas y la mayoría de las exploraciones se han llevado a cabo en zonas adyacentes a vías de comunicación e instituciones educativas y de investigación. Los estudios florísticos cubren un área aproximada de 5600 km2; alrededor de una cuarta parte del territorio ha sido explorado; sin embargo, se requieren expediciones en más de tres cuartas partes del estado, particularmente en el 33% de la ii superficie estatal (7482 km2) que comprende las regiones de la Cuenca del río Balsas, Sierra de Las Cruces, Sierra de Monte Alto, Sierra de Monte Bajo, Sierra de San Andrés y Sierra Nevada, las cuales aún poseen vegetación primaria o vegetación secundaria derivada de la primaria. La similitud florística entre inventarios es baja, lo que indica que cada compilación presenta una flora particular. Amecameca, Ocuilan, Tejupilco, Temascaltepec, Tepotzotlán y Texcoco presentan mayor riqueza. La Depresión del Balsas y las Serranías Meridionales registran mayor cantidad de especies, comparten alrededor del 50% de angiospermas y aproximadamente 40% de las especies de cada provincia son endémicas de México. Entre los municipios potencialmente importantes desde el punto de vista botánico están Almoloya de Alquisiras, Amanalco, Amatepec, Donato Guerra, El Oro, Huixquilucan, Isidro Fabela, Ixtapan del Oro, Jilotzingo, Jiquipilco, Jocotitlán, Morelos, Ocoyoacac, San Simón de Guerrero, San Felipe del Progreso, San José del Rincón, Temascalcingo, Tenango del Valle, Texcaltitlán, Tianguistenco, Villa Guerrero, Villa Victoria y Xalatlaco. El estado de México posee endemismos, angiospermas raras y especies no endémicas pero exclusivas de la entidad, las cuales constituyen grupos prioritarios para la conservación, debido a su vulnerabilidad a la extinciónCONACYT, COMECYT, UAEMEX
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Oudjehih, Bachir. "Étude de la variabilité caryologique dans le genre eucalyptus l'Hérit. (Myrtaceae) : Analyse statistique de la morphologie chromosomique des génomes et comparaison des caryotypes par la technique de "Hy-bands"." Nancy 1, 1987. http://www.theses.fr/1987NAN10050.
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