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Fracionamento de carbono e nitrogênio em café arábica em resposta à carga de frutos / Partition of carbon and nitrogen in coffee arabica in response to fruit loadSilva, Márcio Souza da 22 July 2019 (has links)
As plantas de café (Coffea arabica L.) têm padrão de produção bienal em razão da competição entre o crescimento vegetativo e reprodutivo que ocorrem ao mesmo tempo. A quantificação de compostos de carbono e nitrogênio, bem como o perfil metabólico desses compostos foram investigados a fim de identificar possíveis alterações do crescimento dos tecidos que compõem o ramo produtivo do cafeeiro em resposta à carga de frutos. Os efeitos da carga de frutos foram estudados em quatro estádios fenológicos (expansão inicial, expansão final, granação e maturação de frutos), avaliando-se o crescimento de folhas velhas, maduras e novas; a secção dos ramos em que elas estão inseridas, assim como os frutos. Para isso, manipulações na carga de frutos foram realizadas na planta inteira cultivada em experimento de campo na região de Presidente Olegário, Minas Gerais, Brasil (18° 35\' 25\" S e 46° 19\' 20\" O; 1045 m de altitude). Os tratamentos consistiram em reduzir as cargas de frutos em seu estágio inicial de desenvolvimento a 0%, 30%, 60% e controle mantendo 100% do frutos na árvore. Este estudo demostrou que a alta carga de frutos prejudica principalmente o crescimento da vegetação nova, mas sem nenhum efeito sobre as folhas e ramos já formados. Também foi evidenciado que a alta carga de frutos promove competição entre os frutos afetando o seu tamanho e sua massa unitária. Essa redução do crescimento vegetativo e de frutos se deve principalmente pelo esgotamento de amido nos ramos que contribuem fortemente para o aporte de carbono para os órgãos dreno. A folha velha fornece sacarose para promover o crescimento vegetativo e de frutos, mas esse suprimento de carbono parece não ser suficiente para manutenção do crescimento dos frutos em excesso. Neste caso, o amido é então consumido dos ramos dessas plantas resultando no aumento do teor de sacarose nos ramos e folhas maduras, os quais são os maiores responsáveis por destinar carbono para o crescimento e desenvolvimento dos frutos. Em plantas com carga de frutos reduzida, os órgãos fonte de carbono são diferentes das plantas com alta produção de frutos. Neste caso, o ramo e folha madura fornecem sacarose para o crescimento da vegetação nova e frutos sem gasto aparente do amido acumulado nos ramos. As folhas e os ramos velhos são os principais contribuintes imediatos de nitrogênio, mas os ramos são os principais órgãos fonte desse nutriente tendo grande capacidade de armazenar nitrogênio e de disponibilizá-lo para as plantas sob alta produção de frutos. Assim, o nitrogênio e carbono armazenado nos ramos têm papel fundamental para tamponar a depleção desses nutrientes causada pelo número excessivo de drenos metabólicos. Os frutos das plantas com carga reduzida parecem ter sido sombreados pelo abundante crescimento de folhas e ramos de forma distinta dos frutos oriundos das plantas com carga excessiva de frutos. Esse sombreamento parece ter ocasionado menor grau de maturação dos frutos dessas plantas em razão do aumento dos compostos fenólicos e redução de pectina e antocianina nos frutos e/ou nos seus tecidos. Entretanto, esse efeito sobre a maturação dos frutos é tênue não alterando a quantidade de sacarose e aminoácidos solúveis totais nos frutos e em nenhum dos tecidos que os compõem. Utilizando uma abordagem metabolômica, foi confirmada que os ácidos orgânicos foram influenciados pelo menor grau de maturação dos frutos oriundos das plantas com carga reduzida. Essa evidência também suporta a ideia de que o maior crescimento vegetativo das plantas com carga reduzida pode aumentar o tempo de maturação dos frutos. Analisando o perfil de aminoácidos, foi confirmada que as folhas velhas e maduras são os órgãos fonte principais de nitrogênio para os drenos fisiológicos. A redistribuição de nitrogênio dessas folhas na forma de asparagina, glutamina, tirosina e fenilalanina para os drenos ocorreu em plantas com carga de frutos excessiva. Esse fluxo de nitrogênio para os drenos fisiológicos em conjunto com a degradação de proteínas dos ramos dessas plantas culminaram com aumento de fenialanina nos grãos, glutamina e aspartato nos frutos e alanina nas folhas novas em comparação com as plantas com carga de frutos reduzida. Houve estímulo da síntese de putrescina nos grãos provavelmente como um mecanismo para reajustar o fluxo de carbono e nitrogênio no organismo vegetal inicialmente pertubado em resposta à carga de frutos. Neste sentido, novas investigações pré e pós traducionais precisam ser desenvolvidas a fim de elucidar a interrelação do metabolismo de carbono e nitrogênio para a homeostase de seus metabólitos em resposta à carga de frutos. / Coffee plants (Coffea arabica L.) have a biennial production pattern because of the competition between vegetative and reproductive growth occurring at the same time. The quantification of carbon and nitrogen compounds as well as the metabolic profile of these compounds were investigated in order to identify possible changes in the growth of the tissues of productive branch of the coffee tree in response to the fruit load. The effects of fruit loading were studied in four phenological stages (initial expansion, final expansion, fruit granulation and maturation), evaluating the growth of old, mature and young leaves; the section of the branches in which they are inserted, as well as the fruits. For this, manipulations in the fruit load were carried out on the whole plant cultivated in a field experiment in the region of Presidente Olegário, Minas Gerais, Brazil (18 ° 35\' 25\" S and 46° 19\' 20\'\' O; 1045 m level). The treatments consisted in reducing the loads of fruits in their initial stage of development to 0%, 30%, 60% and control maintaining 100% of the fruits in the tree. This study showed that the high fruit load mainly impairs the growth of young vegetation, but with no effect on already formed leaves and branches. It was also evidenced that the high fruit load promotes competition among the fruits affecting its size and its unit mass. This reduction of vegetative and fruit growth is mainly due to the depletion of starch in the branches that contribute strongly to the carbon supply to the sink organs. Old leaf provides sucrose to promote fruit and vegetative growth, but this carbon supply does not seem to be sufficient to maintain excess fruit growth. In this case, the starch is then consumed from the branches of these plants resulting in the increase of the sucrose content in the mature branches and leaves, which are the main responsible for allocating carbon for the growth and development of the fruits. In plants with reduced fruit load, the carbon source organs are different from plants with high fruit yield. In this case, the branch and mature leaf provide sucrose for the growth of young vegetation and fruit without apparent expense of starch accumulated in the branches. The old leaves and branches are the main immediate contributors of nitrogen, but the branches are the main source organs of this nutrient having great capacity to store nitrogen and to make it available to the plants under high yield of fruits. Thus, the nitrogen and carbon stored in the branches play a fundamental role in buffering the depletion of these nutrients caused by the excessive number of metabolic sinks. The fruits of the plants with reduced load seem to have been shaded by the abundant growth of leaves and branches of distinct form of the fruits originating from the plants with high fruit load. This shading seems to have caused a lower degree of maturation of the fruits of these plants due to the increase of phenolic compounds and reduction of pectin and anthocyanin in fruits and/or their tissues. However, this effect on fruit maturation is tenuous without altering the amount of sucrose and total soluble amino acids in the fruits and in none of the tissues that compose them. Using a metabolomic approach, it was confirmed that the organic acids were influenced by the lower degree of maturation of fruits from the plants with reduced load. This evidence also supports the idea that the higher vegetative growth of the plants with reduced load can increase the maturation time of the fruits. Analyzing the amino acid profile, it was confirmed that the old and mature leaves are the main source organs of nitrogen for the physiological sinks. The nitrogen redistribution of these leaves as asparagine, glutamine, tyrosine and phenylalanine to the drains occurred in plants with excessive fruit load. This nitrogen flow to the physiological sinks together with the protein degradation of the branches of these plants culminated with increase of phenylalanine in the grains, glutamine and aspartate in the fruits and alanine in the young leaves compared to the plants with reduced fruit load. There was stimulation of putrescine synthesis in the grains probably as a mechanism to readjust the carbon and nitrogen flux in the initially disturbed plant organism in response to the fruit load. Thus, new pre- and post-translational research needs to be developed in order to elucidate the interrelation of carbon and nitrogen metabolism to the homeostasis of its metabolites in response to fruit load.
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Effects of Habitat Quality on Behavioural Decisions and Population Dynamics in the Siberian JayNystrand, Magdalena January 2006 (has links)
The dynamics of natural populations may be influenced by a variety of factors, ranging from feeding interference and territoriality to the risk of predation and climatic effects. The relative influence of these factors may be contingent upon the quality of the habitat in which individuals reside. A factor that can largely affect population dynamics and that often covaries with habitat structure is predation risk. However, the combined effect of habitat and predation risk can vary according to the social context and intrinsic characteristics that affect individual behavioural responses. This thesis investigates the effects of habitat quality at the level of the population and the individual, and examines how it relates to the above factors in Siberian jays (Perisoreus infaustus), a territorial, group-living species in which the main cause of mortality is predation. The results demonstrate a strong effect of habitat on survival, reproduction and behaviour. Mortality was generally higher in open areas and managed forests and reproductive success decreased after forest management. Breeding females were more sensitive to environmental factors than males, possibly because of higher reproductive costs. Estimates of spatial demography suggested that there were more sinks than sources, and that they were located in open, managed forests. Behavioural decisions confirmed that open forests were associated with higher predation risks. However, decisions depended on social context; immigrants took highest risks and were the recipients of most aggression, largely an effect of social subordination. Also, parents provide their offspring with benefits that are withheld from immigrants. As a result, first-year survival was higher in retained offspring. Investigating the effects of multi-scale habitat quality on individual behaviour and population dynamics has generated an increased understanding of the effects of forest management on the dynamics of this population. This approach should facilitate development of an effective conservation management policy for this species.
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OXYGEN AND HYDROGEN STABLE ISOTOPE RATIOS IN MISSISSIPPI RIVER FLOODPLAIN INVERTEBRATES: IMPLICATIONS FOR DISPERSAL AND FOOD WEB ANALYSISMyers, David John 01 December 2010 (has links)
Understanding energy fluxes within and between floodplain water bodies, and between rivers and their floodplains is essential for comprehending the dynamics of modern, altered river systems. Floodplain aquatic invertebrates may move between habitats deliberately (through emergence and dispersal) or through passive transport during flooding. This movement may represent a significant flux of energy and an essential food web subsidy. I assessed the usefulness of the stable isotopes of hydrogen and oxygen (D and 18O respectively) for identifying the origins and movements of macroinvertebrates in Mississippi River floodplain water bodies. I sampled water and invertebrates from the Mississippi River, intermittent and permanent floodplain wetlands, and tributaries during 2007 and 2008. Results showed consistent relationships between δD and δ18O signatures in invertebrate tissues and their home water bodies. I also investigated whether δD and δ18O could be used as a multivariate "fingerprint" to trace a captured invertebrate back to its environment of origin. Results showed that δD can be a useful tracer of the movement of floodplain invertebrates in some cases, although δ18O is likely not suitable for that purpose.
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Utilização do carbono-13 como marcador na partição de fotoassimilados em figueiraSilva, Andréa Carvalho da [UNESP] 04 February 2009 (has links) (PDF)
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silva_ac_me_botfca.pdf: 604510 bytes, checksum: 71c5f7d364ff5ed33d5d61f19025419f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho teve como objetivo avaliar, a viabilidade da metodologia para avaliação da translocação e alocação de fotoassimilados, utilizando o isótopo estável do carbono-13 como marcador, assim como, avaliar a relação fonte-dreno nos diferentes órgãos bem como, saber em que órgão se encontraria o carbono-13 após determinados intervalos de tempo, em plantas em estádio reprodutivo da espécie Ficus carica L. Para tanto, uma folha da figueira considerada adulta através da caracterização fotossintética com um medidor portátil de fotossíntese IRGA-6400, foi colocada dentro de uma câmara de acrílico construída para este fim, e submetida a um ambiente com enriquecimento de 13CO2 por 30 minutos. Após 24 horas, os diferentes órgãos presentes nas plantas foram coletados no experimento órgãos drenos, nas demais plantas seguiu-se a experimentação tempo de alocação, onde as plantas de Ficus carica L. foram arrancadas ao longo das horas: 6, 24, 48, 72, 120, 168, 360. Após o tempo especificado as partes (meristema apical, folhas, ramos, caule e sistema radicular) das plantas em estudo foram coletados e imediatamente imersos em nitrogênio líquido (-196 ºC), para evitar que os tecidos permanecessem vivos e conseqüentemente pudessem consumir os fotoassimilados no processo da respiração. As amostras, previamente identificadas foram secas em estufa de circulação forçada a 65º C por 72 horas, em seguida moídas em moinho criogênico, para que houvesse uma perfeita homogeneização, sendo posteriormente analisadas no espectrômetro de massas de razão isotópica, para a determinação do enriquecimento relativo de 13C. Naturalmente a planta apresenta valores de enriquecimento relativo de 13C - 27,92‰, alocando acima de 90% da massa seca e do carbono total nas partes lenhosas. Os resultados obtidos indicaram que figueira se caracteriza como uma planta do ciclo... / The work have planned be quizzed, the feasability of the methodology for evaluation of the fhotosynthates translocation and allocation, using the carbon 13 stable isotope a marker, evaluate the source-sink relation in the different organs and, know in that organ would be found the carbon-13 after determined time periods, in Ficus carica L. plants in reproductive stadium. A fig tree leaf considered adult through the photosynthetic with a portable meter of photosynthesis IRGA-6400 characterization. Was put inside a acrylic chamber, and submitted to an environment with 13CO2 enrichment for 30 minutes. After 24 hours, the different organs present in the plants were collected in the drains organs experiment, in the other plants followed the allocation time experimentation where the plants of Ficus carica L. were lurches to the long one of the hours: 6, 24, 48, 72, 120, 168, 360. After the time specified the studied plant parts (meristem, sheets, branches, stem and system roots) were collected and immediately immersed in liquid nitrogen (-196 ºC), for avoid that the fabrics remained alive and consequently could consume the fhotosynthates in the breath trial. The samples, previously identified were droughts in of circulation forced to 65º C for 72 hours, right away ground in cryogenic mill, for that had a perfect homogenization, being subsequently analyzed in the mass spectrometry of isotopic reason, for the relative enrichment... (Complete abstract click electronic access below)
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Maintaining biodiversity with a mosaic of wetlands: factors affecting amphibian species richness among small isolated wetlands in central Florida.Guzy, Jackie 30 June 2010 (has links)
The biodiversity value of a wetland is linked not only to its position in the landscape relative to other wetlands, but also to its habitat characteristics. I monitored amphibian species richness among 12 small, isolated, and undisturbed wetlands (which occur on lands permitted for phosphate mining) in central Florida during the 2005 and 2006 breeding seasons. I used seven habitat and landscape variables to characterize the environments of the wetlands and generalized linear models to determine which of these variables had the greatest influence on the occurrence of seven amphibian species (Anaxyrus terrestris, Gastrophryne carolinensis, Hyla gratiosa, Lithobates capito, L. catesbeianus, L. grylio, and Pseudacris nigrita verrucosa). Significant models for each species incorporated six of the seven habitat and landscape variables: distance to permanent water (2 spp.), distance to nearest wetland (3 spp.), vegetation heterogeneity (2 spp.), hydroperiod (2 spp.), presence/absence of fish (1 sp.), and distance to canopy cover (1 sp.). I suggest that source/sink metapopulation and patchy population dynamics in a given year are affected in part by environmental variables of ephemeral wetlands as they affect individual amphibian species. I suggest that a diversity of environmental conditions among wetlands produces the greatest amphibian biodiversity in this system, and that conservation and restoration efforts should emphasize environmental heterogeneity.
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Population ecology of the harvested understory palm Chamaedorea radicalis: pollination biology, female fecundity, and source-sink population dynamicsBerry, Eric J. 27 June 2006 (has links)
No description available.
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Trait Variation and Long-term Population Dynamics of the Invasive Alliaria Petiolata (Garlic Mustard) Across Three Microhabitats in its Invaded RangeHancock, Laura 01 February 2021 (has links) (PDF)
Long-term population dynamics across heterogeneous environments can be a major factor in determining species’ ability to expand their ranges and persist in novel environments. Whether and how the relative performance of populations in different microsites over time impacts invasion into new microsites is poorly understood. Though largely restricted to disturbed semi-shaded microhabitats in its home range, the invasive herb Alliaria petiolata (garlic mustard) successfully invades intact forest understories – a novel microhabitat – in its introduced range, where it is known to impact above and below ground community composition. To test the hypothesis that source-sink metapopulation dynamics may be promoting A. petiolata’s incursion into the forest understory, I utilized two multi-season field surveys – approximately a decade apart – to evaluate trait variation, biomass allocation, and long-term population demographics of A. petiolata growing at the forest edge, within the intact forest understory, and in the intermediate transition zone between the two. My results show that adult plants in the edge were taller and branchier, produced more fruits, and had higher total and reproductive biomass than plants in the intermediate and forest microhabitats. Over time, seedling density remained highest in the edge microhabitat compared to the forest and intermediate microhabitats, which had similar densities. Reproductive adult densities were similar among all microhabitats at the beginning of the study, but a decade later, all microhabitats exhibited a decline in the number of adult plants they supported. Populations in the intermediate microhabitat displayed the steepest decline in reproductive adults between sampling periods but still supported more adult plants than the forest microhabitat. Populations in all microhabitats were predicted to grow (λ>1) at the onset of the study. A decade later, declines in population size were only predicted in the forest understory (λ1). Since edge and intermediate patches had higher densities of adult plants which produced the most fruit and had larger reproductive biomass, it appears that the edge populations, and possibly the intermediate populations, have sustained the low-density forest populations through source-sink dynamics at my study sites.
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Chaos in Pulsed Laminar FlowKumar, Pankaj 01 September 2010 (has links)
Fluid mixing is a challenging problem in laminar flow systems. Chaotic advection can play an important role in enhancing mixing in such flow. In this thesis, different approaches are used to enhance fluid mixing in two laminar flow systems.
In the first system, chaos is generated in a flow between two closely spaced parallel circular plates by pulsed operation of fluid extraction and reinjection through singularities in the domain. A singularity through which fluid is injected (or extracted) is called a source (or a sink). In a bounded domain, one source and one sink with equal strength operate together as a source-sink pair to conserve the fluid volume. Fluid flow between two closely spaced parallel plates is modeled as Hele-Shaw flow with the depth averaged velocity proportional to the gradient of the pressure. So, with the depth-averaged velocity, the flow between the parallel plates can effectively be modeled as two-dimensional potential flow. This thesis discusses pulsed source-sink systems with two source-sink pairs operating alternately to generate zig-zag trajectories of fluid particles in the domain. For reinjection purpose, fluid extracted through a sink-type singularity can either be relocated to a source-type one, or the same sink-type singularity can be activated as a source to reinject it without relocation. Relocation of fluid can be accomplished using either "first out first in" or "last out first in" scheme. Both relocation methods add delay to the pulse time of the system. This thesis analyzes mixing in pulsed source-sink systems both with and without fluid relocation. It is shown that a pulsed source-sink system with "first out first in" scheme generates comparatively complex fluid flow than pulsed source-sink systems with "last out first in" scheme. It is also shown that a pulsed source-sink system without fluid relocation can generate complex fluid flow.
In the second system, mixing and transport is analyzed in a two-dimensional Stokes flow system. Appropriate periodic motions of three rods or periodic points in a two-dimensional flow are determined using the Thurston-Nielsen Classification Theorem (TNCT), which also predicts a lower bound on the complexity generated in the fluid flow. This thesis extends the TNCT -based framework by demonstrating that, in a perturbed system with no lower order fixed points, almost invariant sets are natural objects on which to apply the TNCT. In addition, a method is presented to compute line stretching by tracking appropriate motion of finite size rods. This method accounts for the effect of the rod size in computing the complexity generated in the fluid flow. The last section verifies the existence of almost invariant sets in a two-dimensional flow at finite Reynolds number. The almost invariant set structures move with appropriate periodic motion validating the application of the TNCT to predict a lower bound on the complexity generated in the fluid flow. / Ph. D.
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Étude de l'allocation du carbone dans la plante en réponse à la contrainte hydrique : impact sur l'expression des transporteurs de saccharose dans les organes source et puits / Study of plant carbon allocation under water deficit : impact on sucrose transporters genes expression in source and sink organsDurand, Mickael 11 December 2015 (has links)
L’objectif de cette thèse était d’étudier les transporteurs de saccharose impliqués dans le développement des organes puits, et plus précisément leur rôle dans la racine des plantes soumises à la contrainte hydrique.L’expression des transporteurs AtSUCs et AtSWEETs a été cartographiée, au cours du développement complet de plantes A. thaliana cultivées en hydroponie, dans la rosette, la hampe, les siliques et les racines. En parallèle, nous avons évalué l’allocation du carbone et le métabolisme des sucres dans la plante entière au cours du développement pour finalement (1) avoir un aperçu de l’allocation du carbone, du métabolisme des sucres ainsi que de l’expression des transporteurs de saccharose et (2) discuter leurs possibles relations.Dans un second temps, nous avons conçu un système de culture en sol innovant appelé « Rhizobox » permettant la récolte de racines propres, l’analyse de l’architecture du système racinaire et l’application de la contrainte hydrique. Lors de la contrainte hydrique, la croissance racinaire est réduite, mais l’exploration en profondeur du système racinaire est maintenue probablement pour améliorer l’absorption d’eau. De plus, même si la rosette soumise à la contrainte hydrique était plus petite, l’export de 14C, vers la racine, était augmenté. Dans le même temps, les niveaux de transcrits des gènes de facilitateurs de saccharose AtSWEET11 et AtSWEET12 ainsi que du gène AtSUC2, un symporteur saccharose:H+ spécifique de la cellule compagne, tous trois impliqués dans le chargement du saccharose dans le phloème, étaient augmentés dans les feuilles des plantes soumises à la contrainte hydrique, corroborant l’augmentation de l’export du carbone vers la racine. De façon intéressante, les niveaux de transcrits des gènes AtSUC2 et d’ASWEET11-15, étaient plus élevés dans les racines stressées, soulignant (1) la potentielle existence d’un déchargement apoplastique du saccharose dans la racine d’A. thaliana et (2) un rôle putatif pour ces transporteurs de saccharose dans le déchargement du saccharose dans la racine étant donné qu’ils sont principalement exprimés dans les zones de la racine où la demande en carbone est importante. / The aim of this thesis was to investigate the sucrose transporters involved in sink organs development, and more precisely their role in roots of plants submitted to water deficit.The expression of AtSUCs and AtSWEETs transporters was mapped during the full development of A. thaliana plants grown hydroponically in rosette, stem, siliques and roots. In parallel, we evaluated C partitioning and sugar metabolism in whole plant during development to finally (1) get an insight on C allocation, sugar metabolism and sucrose transporters genes expression and (2) discuss their possible relationships.Secondly, we designed an innovating soil culture system, called “Rhizobox” which allows clean roots harvest, root system architecture analysis and water deficit experiment. Under water deficit, root growth was reduced, but in depth root exploration was maintained probably to improve water uptake. In addition, although shoot submitted to water deficit were smaller, 14C exported to the roots increased. In the same time, the transcript levels of the sucrose effluxers gene AtSWEET11 and AtSWEET12 and the companion-cell specific sucrose:H+ symporter gene AtSUC2, all three involved in sucrose phloem loading, are up-regulated in leaves of water deficit plants, agreeing with the increase in carbon export to the roots. Interestingly, the transcript levels of AtSUC2, and AtSWEET11-15, were higher in stressed roots, underlying (1) the potential existence of sucrose apoplastic unloading in Arabidopsis roots and (2) a putative role for these sucrose transporters in sucrose unloading in root since they are mainly expressed in root zones where C demand is high.
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Utilização do carbono-13 como marcador na partição de fotoassimilados em figueira /Silva, Andréa Carvalho da , 1981- January 2009 (has links)
Resumo: O trabalho teve como objetivo avaliar, a viabilidade da metodologia para avaliação da translocação e alocação de fotoassimilados, utilizando o isótopo estável do carbono-13 como marcador, assim como, avaliar a relação fonte-dreno nos diferentes órgãos bem como, saber em que órgão se encontraria o carbono-13 após determinados intervalos de tempo, em plantas em estádio reprodutivo da espécie Ficus carica L. Para tanto, uma folha da figueira considerada adulta através da caracterização fotossintética com um medidor portátil de fotossíntese IRGA-6400, foi colocada dentro de uma câmara de acrílico construída para este fim, e submetida a um ambiente com enriquecimento de 13CO2 por 30 minutos. Após 24 horas, os diferentes órgãos presentes nas plantas foram coletados no experimento órgãos drenos, nas demais plantas seguiu-se a experimentação tempo de alocação, onde as plantas de Ficus carica L. foram arrancadas ao longo das horas: 6, 24, 48, 72, 120, 168, 360. Após o tempo especificado as partes (meristema apical, folhas, ramos, caule e sistema radicular) das plantas em estudo foram coletados e imediatamente imersos em nitrogênio líquido (-196 ºC), para evitar que os tecidos permanecessem vivos e conseqüentemente pudessem consumir os fotoassimilados no processo da respiração. As amostras, previamente identificadas foram secas em estufa de circulação forçada a 65º C por 72 horas, em seguida moídas em moinho criogênico, para que houvesse uma perfeita homogeneização, sendo posteriormente analisadas no espectrômetro de massas de razão isotópica, para a determinação do enriquecimento relativo de 13C. Naturalmente a planta apresenta valores de enriquecimento relativo de 13C - 27,92‰, alocando acima de 90% da massa seca e do carbono total nas partes lenhosas. Os resultados obtidos indicaram que figueira se caracteriza como uma planta do ciclo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The work have planned be quizzed, the feasability of the methodology for evaluation of the fhotosynthates translocation and allocation, using the carbon 13 stable isotope a marker, evaluate the source-sink relation in the different organs and, know in that organ would be found the carbon-13 after determined time periods, in Ficus carica L. plants in reproductive stadium. A fig tree leaf considered adult through the photosynthetic with a portable meter of photosynthesis IRGA-6400 characterization. Was put inside a acrylic chamber, and submitted to an environment with 13CO2 enrichment for 30 minutes. After 24 hours, the different organs present in the plants were collected in the drains organs experiment, in the other plants followed the allocation time experimentation where the plants of Ficus carica L. were lurches to the long one of the hours: 6, 24, 48, 72, 120, 168, 360. After the time specified the studied plant parts (meristem, sheets, branches, stem and system roots) were collected and immediately immersed in liquid nitrogen (-196 ºC), for avoid that the fabrics remained alive and consequently could consume the fhotosynthates in the breath trial. The samples, previously identified were droughts in of circulation forced to 65º C for 72 hours, right away ground in cryogenic mill, for that had a perfect homogenization, being subsequently analyzed in the mass spectrometry of isotopic reason, for the relative enrichment... (Complete abstract click electronic access below) / Orientador: Sarita Leonel / Coorientador: Carlos Ducatti / Banca: João Domingos Rodrigues / Banca: Marco Antonio da Silva Vasconcellos / Mestre
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