Tesis sobre el tema "Soil DNA"
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Mueller, Sabrina R. "Chromium, DNA, and Soil Microbial Communities". Cincinnati, Ohio : University of Cincinnati, 2006. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1141334651.
Texto completoAdvisor: Brian K. Kinkle. Title from electronic thesis title page (viewed Apr. 23, 2009). Keywords: SEC-ICP-MS; Fungal community; bacterial community; DGGE. Includes abstract. Includes bibliographical references.
Kapadia, Jaimin Maheshbhai. "DNA transfer in the soil bacterium Rhodococcus". Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/honors/565.
Texto completoau, N. Williams@murdoch edu y Nari Michelle Anderson. "DNA methods for the detection of Phytophthora cinnamomi from soil". Murdoch University, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070820.130155.
Texto completoAnderson, Nari Michelle. "DNA methods for the detection of Phytophthora cinnamomi from soil". Thesis, Anderson, Nari Michelle (2006) DNA methods for the detection of Phytophthora cinnamomi from soil. PhD thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/42/.
Texto completoAnderson, Nari Michelle. "DNA methods for the detection of Phytophthora cinnamomi from soil". Anderson, Nari Michelle (2006) DNA methods for the detection of Phytophthora cinnamomi from soil. PhD thesis, Murdoch University, 2006. http://researchrepository.murdoch.edu.au/42/.
Texto completoKasu, Mohaimin. "The validation of forensic DNA extraction systems to utilize soil contaminated biological evidence". Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/5921.
Texto completoSmart, Trevor Blake. "Microbial Community Response to Fumigation in Potato Soils". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7355.
Texto completoHe, Jizheng y n/a. "Molecular Biological Studies of Soil Microbial Communities Under Different Management Practices in Forest Ecosystems of Queensland". Griffith University. Australian School of Environmental Studies, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20060309.095702.
Texto completoHe, Jizheng. "Molecular Biological Studies of Soil Microbial Communities Under Different Management Practices in Forest Ecosystems of Queensland". Thesis, Griffith University, 2005. http://hdl.handle.net/10072/367075.
Texto completoThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
Full Text
Spiegelman, Dan. "Exploring the fusion of metagenomic library and DNA microarray technologies". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98805.
Texto completoCappelini, Luciana Teresa Dias. "Influência das substâncias húmicas na degradação do pesticida fipronil pela bactéria Burkholderia sp". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-30072013-093208/.
Texto completoDue to the expansion of sugar cane, and the high costs of agricultural inputs, currently looking up forms new of soil management among them the use of humic substances. Nevertheless producers combine traditional and alternative techniques, for example addition of fipronil to humic substances. Fipronil is an insecticide phenyl - pyrazole widely used in cane sugar cultivation . Despite this practice, few is known about a biotic degradation of the fipronil, fipronil sulfide and fipronil sulfone, when using humic substances as fertilization. Therefore the objective of this study was to evaluate the biological degradation of fipronil when it used in humic substances. For this study, we used an indirect method of DNA extraction from the soil, where bacteria were cultured in medium containing only sterile water and fipronil. After, the DNA was extracted,a PCR was performing using primer 27F/1100Rr and the PCR product was cloned and sequenced. The bacteria identified were affiliated to the genus Clostridium sp., Bdellovibrio sp., Flavisolibacter sp., Burkholderia sp. and Herbaspirillum sp. The gene selected for the study was affiliated with Burkholderia sp due to its potential degradation reported in the literature. The study strain was acquired in public banks, and was selected to Burkholderia thailandensis. For the determination of fipronil and its metabolites, the method QuEChERS follow by analysis with GC-MS was validated to fipronil, fipronil sulfide, and fipronil sulfone. To this method was found the follow conditions: detection and quantitation limits were 0.06 mg L-1 0.25 mgL-1 respectively, the linearity was 0.99, the precision was about 10.9 to 7.3% for the lowest level and 1.84 to 1.24% for the highest level. We calculated the recovery of the extraction method which ranged between 78 and 98%. Then were assembled eight treatments, to evaluate the degradation of the fipronil and the formation of its two degradation products biotic, fipronil sulfide and fipronil sulfone, when using humic substances in fertilization. The Burkholderia thailandensis degraded approximately 0.75 mg L-1 fipronil with or without the presence of SH in the study soil, but it was not possible to quantify the degradation products of the fipronil (fipronil sulfide and fipronil sulfone) because both were detected but cannot be quantified because their values are below the limit of quantification of the method.
Rosa, Márcia Maria. "Avaliação de diferentes metodologias para extração de DNA de solo sob cultivo de cana-de-açúcar /". Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/95004.
Texto completoAbstract: Soil is an ecosystem characterized by a great complexity and hard to study due to its heterogeneity, especially the soil microorganisms. Nowadays, molecular biology tools have been used to show the biotechnological potential of the soil mainly through microbial genes. Direct extraction of DNA from soil is an important step in this kind of study, however it is still an obstacle for microbial diversity evaluation. Besides, the majority of techniques proposed was developed for soils from temperate climate. This work aimed to evaluate ten different techniques for soil direct DNA extraction from sugar cane crop areas under organic and conventional managements, which presented distinct results. Gel electrophoresis was the most appropriate technique to evaluate the efficiency of DNA extraction, through the intensity and size of the bands. The Selbach technique (SEL) showed the best results, with more intense DNA bands and without smearing , indicating that a DNA solution with low concentration of contaminants was obtained. With the Direito technique (DIR) DNA bands were also verified, but less intensive and also without smearing. The technique proposed in this study (PRO) resulted in intense DNA however with smearing, indicating that a DNA purification step is necessary. This technique was easy, cheap and rapid to execute, enabling the amplification of 16S rDNA (using universal primers) after DNA solution purification. The intensity of DNA bands, as revealed by electrophoresis, was higher when using DNA solution extracted from soil under organic management, which also presented higher microbial biomass. This study is a contribuition for the selection and improvement of molecular tools to the study of microbial diversity applied to Brazilian soils.
Orientador: Sâmia Maria Tauk-Tornisielo
Coorientador: Sandra Regina Ceccato-Antonini
Banca: Marli de Fatima Fiore
Banca: Welington Luiz de Araujo
Mestre
Rosa, Márcia Maria [UNESP]. "Avaliação de diferentes metodologias para extração de DNA de solo sob cultivo de cana-de-açúcar". Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/95004.
Texto completoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O solo é um ecossistema caracterizado pela grande complexidade de difícil estudo, devido à sua heterogeneidade, especialmente os microrganismos do solo. Atualmente, ferramentas da biologia molecular têm sido usadas para mostrar o potencial biotecnológico do solo, através dos genes microbianos. A extração direta do DNA é uma etapa importante nesse tipo de estudo, porém, continua sendo um obstáculo para a avaliação da diversidade microbiana do solo. Esses estudos no Brasil apresentam algumas dificuldades, uma vez que a maioria das técnicas foi desenvolvida para solos de clima temperado. Desta forma, o objetivo deste estudo foi avaliar dez diferentes técnicas para extração direta de DNA de solos em áreas de cultura de cana-de-açúcar sob manejo orgânico e convencional. A eletroforese se apresentou como a técnica mais adequada para se conhecer a eficiência da extração do DNA, através da intensidade e tamanho de suas bandas. A técnica de Selbach (SEL) apresentou melhores resultados, com bandas de DNA mais intensas e sem arraste, indicando a obtenção de uma solução com menores teores de contaminantes. Com a técnica de Direito (DIR) também se verificou bandas de DNA, porém menos fortes e sem arraste. A técnica proposta neste estudo (PRO) resultou em bandas de DNA fortes, porém com arraste, indicando a necessidade de uma etapa para purificação do DNA extraído. Esta mostrou ser a metodologia de mais fácil e rápida execução, sendo que, após processo de purificação a região 16S do DNA ribossomal, utilizando-se primers universais, foi amplificada satisfatoriamente a partir do DNA obtido do solo. Bandas de DNA apresentadas na eletroforese a partir das amostras de solo sob viii manejo orgânico foram mais intensas do que aquelas de manejo convencional. Estes resultados estão relacionados com a maior quantidade de biomassa microbiana presente no solo orgânico... .
Soil is an ecosystem characterized by a great complexity and hard to study due to its heterogeneity, especially the soil microorganisms. Nowadays, molecular biology tools have been used to show the biotechnological potential of the soil mainly through microbial genes. Direct extraction of DNA from soil is an important step in this kind of study, however it is still an obstacle for microbial diversity evaluation. Besides, the majority of techniques proposed was developed for soils from temperate climate. This work aimed to evaluate ten different techniques for soil direct DNA extraction from sugar cane crop areas under organic and conventional managements, which presented distinct results. Gel electrophoresis was the most appropriate technique to evaluate the efficiency of DNA extraction, through the intensity and size of the bands. The Selbach technique (SEL) showed the best results, with more intense DNA bands and without smearing , indicating that a DNA solution with low concentration of contaminants was obtained. With the Direito technique (DIR) DNA bands were also verified, but less intensive and also without smearing. The technique proposed in this study (PRO) resulted in intense DNA however with smearing, indicating that a DNA purification step is necessary. This technique was easy, cheap and rapid to execute, enabling the amplification of 16S rDNA (using universal primers) after DNA solution purification. The intensity of DNA bands, as revealed by electrophoresis, was higher when using DNA solution extracted from soil under organic management, which also presented higher microbial biomass. This study is a contribuition for the selection and improvement of molecular tools to the study of microbial diversity applied to Brazilian soils.
Kumpula, Kimmo. "Systematic comparison of the relative accuracy of vegetation surveys and soil DNA metabarcoding : Assessing plant biodiversity at different spatial scales". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-172130.
Texto completoIgun, Onotasamiderhi Tarric. "Employing the power of DNA-based microbial community structure analysis for the rational design of hydrocarbon contaminated soil remediation". Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3796.
Texto completoDiawara, Aïssatou. "Development of DNA assays for the detection of single nucleotide polymorphism associated with benzimidazole resistance, in human soil-transmitted helminths". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19242.
Texto completoLes géo-helminthes sont des vers parasitant l'Homme et causant de nombreux handicaps dans les régions tropicales des pays en voie de développement. Des programmes de contrôles tels que le partenariat FRESH : ''Focussing Resources on Effective School Health'' ont été mis en place afin d'éliminer les géo-helminthes en administrant massivement en milieu scolaire des pays en voie de développement des medicaments anthelmintiques. L'albendazole et le mébendazole appartiennent au groupe des benzimidazoles et sont distribués dans les régions grandement infestées. Cependant, cette attribution massive de médicaments, aux enfants, pourrait entraîner une sélection de parasites résistants aux anthelmintiques. La substitution de l'acide aminé phénylalanine (Phe) par la tyrosine (Tyr) connue pour être associée à la résistance aux benzimidazoles chez les nématodes a été identifiée chez les filaires à la position 200 du gène de la ß-tubuline. Nous avons développés des tests pour les parasites Trichuris trichiura, Ascaris lumbricoides et Necator americanus en utilisant la méthode du pyroséquençage afin de détecter le polymorphisme d'un unique nucleotide (SNP) au niveau du codon 200 du gène de la ß-tubuline. Ce test a été appliqué sur des vers adultes provenant d'individus du Kenya n'ayant jamais été traités par des anthelmintiques. Puis ce même test a été appliqué à des vers adultes individuels, à des pools d'œufs et de larves provenant d'individus d'Afrique de l'est, des Caraïbes et d'Amérique centrale, où les programmes de contrôles de masse sont implantés. Le SNP fût détecté chez T. trichiura provenant d'individus non-traités aux benzimidazoles ainsi que chez T. trichiura et N. ameri
Pillai, Suresh Divakaran. "Ecology and genetic stability of Tn5 mutants of bean rhizobia in Sonoran desert soils". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184823.
Texto completoHorton, Dean J. "Using molecular techniques to investigate soil invertebrate communities in temperate forests". Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1448799316.
Texto completoMoreno, Lilliana I. "The Effect of Sample and Sample Matrix on DNA Processing: Mechanisms for the Detection and Management of Inhibition in Forensic Samples". FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1764.
Texto completoBuckley, Elan. "Change in the Structure of Soil Microbial Communities in Response to Waste Amendments". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/101499.
Texto completoM.S.
Soil is complicated, both in terms of its physical makeup and the organisms that live inside of it. Predicting changes in soil based on the addition of foreign material such as chemicals or biological waste is not an easy process, and whether or not it is even possible to reliably predict those changes is a matter of some dispute. This study is designed to illustrate that such changes can in fact be reliably and consistently predicted even with regard to the addition of complicated materials to the soil. In this study, specifically, the material in question is chicken litter. A mix of the bedding and waste produced by chickens, litter is commonly handled by composting and is added to soil in farms as a fertilizer rich in organic matter. It is possible to point at specific elements of the soil such as the chemistry and bacteria and see how it is changed with the addition of chicken litter, which allows us to determine the nature and extent of the change that chicken litter has on soil. This study is conducted on a larger scale than similar experiments conducted in the past, making it apparent that these relationships exist on a repeated basis. It is the object of this study to pave the way and make it easier for scientists in the future to determine these relationships in other unique contexts.
Mattiello, Lucia. "Fisiologia e transcriptoma de milho cultivado em solo ácido". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317449.
Texto completoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-16T10:26:16Z (GMT). No. of bitstreams: 1 Mattiello_Lucia_D.pdf: 1855407 bytes, checksum: 309c252e258389c8f81e79e8fba49e74 (MD5) Previous issue date: 2010
Resumo: A presença do alumínio (Al) em solos ácidos é o principal fator limitante da produtividade agrícola no Brasil e no mundo. A resposta desenvolvida pelas plantas contra o Al é complexa e a identificação de genes responsivos após a exposição ao íon através de técnicas de análise em larga escala, como microarrays, pode facilitar a sua compreensão. Este projeto possui como objetivo ampliar o conhecimento sobre a fisiologia e a regulação gênica de raízes e folhas utilizando genótipos contrastantes de milho (Cat100-6 (Al-tolerante) e S1587-17 (Al-sensível)) cultivadas em solo ácido com concentração fitotóxica de Al. As linhagens de milho Cat100-6 e S1587-17 foram cultivadas por um ou três dias em solo ácido (pH 4,1) ou solo corrigido com Ca(OH)2 (pH 5,5). O genótipo S1587-17 apresentou uma maior inibição do crescimento radicular, resultado este altamente correlacionado com a acumulação de Al nos ápices radiculares e deposição de calose. Os dados fisiológicos confirmam a discriminação entre as duas linhagens em solo, abrindo perspectivas para entender pela primeira vez a base molecular das alterações das plantas em condições próximas à realidade de campo. O transcriptoma de raízes possibilitou a identificação possíveis candidatos a tolerância ao Al. Adicionalmente, com um experimento de hidroponia separamos as variáveis pH e presença de Al, ambas condições diferenciais do tratamento com solo. Identificamos, entre os candidatos, genes responsivos pela presença do Al e não pela acidez delimitando assim os genes com possíveis papéis na tolerância ao Al presente no solo ácido a apenas três: retinol desidrogenase, um fator de transcrição WRKY e uma proteína desconhecida. Esses resultados permitem concluir que o cultivo em solo é diferencial em relação à hidroponia, e outros fatores que apenas presentes no substrato solo podem provocar a indução de alguns genes. Diversas vias metabólicas são afetadas na linhagem sensível pelo tratamento em solo ácido e podem estar envolvidas na inibição radicular como a produção de lignina, celulose e calose e a síntese de etileno e auxina. O mapeamento nos cromossomos dos genes identificados pelo experimento de microarray das raízes de milho permitiu a identificação de genes localizados dentro de QTLs de milho previamente descritos na literatura como responsáveis pelo fenótipo tolerante. Diante esse resultado, podemos especular o papel de genes como uma proteína ligadora de RNA, uma inibidora de proteases e ciclinas na tolerância ao Al contido no solo ácido. Pela primeira vez na literatura, o transcriptoma de folhas coletadas após três dias de cultivo em solo ácido ou solo corrigido foi obtido com o uso de microarrays da Affymetrix. Essa análise indicou profundas alterações na Cat100-6, em contraposição à ausência de alteração significativa nas folhas na S1587-17. Genes referentes à fotossíntese e a fotorrespiração foram regulados negativamente pelo tratamento em solo ácido no genótipo tolerante. Contudo, o ciclo do ácido cítrico está ativado indicando uma putativa participação da produção de ácidos orgânicos nas folhas na resposta ao Al
Abstract: The presence of aluminum (Al) is the main factor limiting crops yield in Brazil and worldwide. The plant responses developed against this ion are complex and the identification of responsive genes after exposure to the ion with the use of a large scale technique, such as microarrays, can facilitate its comprehension. This project aimed to amplify the knowledge about physiology and gene expression regulation of roots and leaves associated towards Al resistance using contrasting maize genotypes (Cat100-6 (Al-tolerant) and S1587-17 (Al-sensitive) cultivated in acid soil containing phytotoxic concentrations of Al. Maize lines Cat100-6 and S1587-17 were cultivated for one or three days in acid soil (pH 4,1) or limed soil with Ca(OH)2 (pH 5,5). The genotype S1587-17 presented a higher root growth inhibition, which is highly correlated with Al accumulation in the root apexes and callose deposition. The physiological data confirms the discrimination of the two maize lines cultivated in soil, opening perspective to understand for the first time the molecular bases of alterations in plants on a closer condition to the field. Transcriptome from roots made possible the identification of possible tolerance candidates and genes constitutively expressed genes in the tolerant line. Additionally, throw a hydroponic experiment we splited the variables pH and Al presence, both differential conditions between soil treatments. It was possible to identify, among the candidates, genes responsive in the presence of Al in acid soil rather than acidity limiting genes with a possible roles in Al present in the acid soil tolerance to only three: retinol dehydrogenase, the transcription factor WRKY and an unknown protein. These results allow the conclusion that the soil culture is different in relation to hydropony, and other factors present only in soil substrate could provoke the induction of some genes. Several metabolic pathways were affected in the sensitive line after acid soil growth and could be involved on root growth inhibition such as lignin, cellulose and callose production and ethylene and auxin synthesis. The mapping of the identified genes through the microarray experiments into the chromosomes allowed the identification of genes localized into maize QTLs previously reported in the literature as responsible for the tolerant phenotype. Facing these results, we can speculate the role of these genes such as a RNA binding protein, a protease inhibitor, and cyclines in the Al present in the acid soil tolerance. For the first time in literature, the transcriptome of leaves collected after three days in culture with acid soil or limed soil with the Affymetrix microarrays. This analysis indicated great alterations in Cat100-6, meanwhile S1587-17 showed no significative alteration. Genes related to photosynthesis and photorespiration were down-regulated due acid soil treatment in the tolerant genotype. However, citric acid cycle was activated indicating the putative partitipation of organic acids produced in the leaves in thr Al response
Doutorado
Genetica Vegetal e Melhoramento
Doutor em Genetica e Biologia Molecular
Sommeria-Klein, Guilhem. "From models to data : understanding biodiversity patterns from environmental DNA data". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30390/document.
Texto completoIntegrative patterns of biodiversity, such as the distribution of taxa abundances and the spatial turnover of taxonomic composition, have been under scrutiny from ecologists for a long time, as they offer insight into the general rules governing the assembly of organisms into ecological communities. Thank to recent progress in high-throughput DNA sequencing, these patterns can now be measured in a fast and standardized fashion through the sequencing of DNA sampled from the environment (e.g. soil or water), instead of relying on tedious fieldwork and rare naturalist expertise. They can also be measured for the whole tree of life, including the vast and previously unexplored diversity of microorganisms. Taking full advantage of this new type of data is challenging however: DNA-based surveys are indirect, and suffer as such from many potential biases; they also produce large and complex datasets compared to classical censuses. The first goal of this thesis is to investigate how statistical tools and models classically used in ecology or coming from other fields can be adapted to DNA-based data so as to better understand the assembly of ecological communities. The second goal is to apply these approaches to soil DNA data from the Amazonian forest, the Earth's most diverse land ecosystem. Two broad types of mechanisms are classically invoked to explain the assembly of ecological communities: 'neutral' processes, i.e. the random birth, death and dispersal of organisms, and 'niche' processes, i.e. the interaction of the organisms with their environment and with each other according to their phenotype. Disentangling the relative importance of these two types of mechanisms in shaping taxonomic composition is a key ecological question, with many implications from estimating global diversity to conservation issues. In the first chapter, this question is addressed across the tree of life by applying the classical analytic tools of community ecology to soil DNA samples collected from various forest plots in French Guiana. The second chapter focuses on the neutral aspect of community assembly.[...]
Whissell, Gavin. "Merging metagenomic and microarray technologies to explore bacterial catabolic potential of Arctic soils". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98518.
Texto completoParaskova, Julia V. "Organic phosphorus speciation in environmental samples : Method development and applications". Doctoral thesis, Uppsala universitet, Institutionen för kemi - BMC, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-228734.
Texto completoSullivan, Madsen Paul. "Effects of and Influences on Microbial Populations of Missouri Maize Fields". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7706.
Texto completoSampietro, Bergua Mª Lourdes. "Genetic Analysis of the prehistoic peopling of Western Europe: Ancient DNA the role of contamination". Doctoral thesis, Universitat Pompeu Fabra, 2007. http://hdl.handle.net/10803/79128.
Texto completoEn la presente tesis hemos tratado tres temas diferentes aunque muy relacionados. Primero, hemos estudiado la tasa de mutación post-mortem de secuencias de ADN contaminante en restos humanos antiguos centrándonos en el desarrollo de estrategias para evitar que las muestras se contaminen antes de llegar al laboratorio. Proponemos una guía que consiste en el tipado genético de cada persona implicada en la manipulación de los restos, especialmente cuando estos han sido excavados y lavados bajo condiciones no controladas. Segundo, hemos desarrollado una técnica no invasiva para secuenciar DNA de restos humanos antiguos pero sin destruirlos. Y por ultimo, hemos secuenciado restos humanos antiguos pertenecientes a diferentes periodos evolutivos (desde el Paleolitico hasta el post-Neolitico) que nos han permitido hacer inferencias sobre el poblamiento Europeo centrándonos básicamente en la Península Ibérica. Hemos encontrado que ha habido una continuidad genética desde el Neolítico. La única clara discontinuidad genética encontrada es entre dos especies distintas: H. Sapiens y H.neanderthalensis.
Cury, Juliano de Carvalho. "Diversidade de Bacteria e Archaea em solos de mangue e marisma". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-11122006-144427/.
Texto completoThe bacterial diversity in mangrove (Brazil) and marisma (Espanha) soils are largely unknown. Bacterial communities participate in biogeochemicals processes that occurs in soils of estuarine ecosystems. Determinations of the bacterial communities structures and diversity can occur in function of different physico-chemical conditions, reflecting in the biogeochemical processes. The aim of this work was to evaluate the variation of bacterial an archaeal communities structures utilizing DGGE and partial sequencing of 16S rDNA. Bacterial community structures showed more similarity between repetitions samples than the areas under different vegetation. Phylogenetic afiliation shows that several sequences were not clamped into known phyla. Proteobacteria prevails in bacterial communities of mangrove and marisma soils. Several taxa detected are associated to important biogeochemical cycles that occur in estuarine ecosystems. Analysis of species richness showed that mangrove and marisma soils can contain 200 to 6000 species of bacteria. Methanogenic Euryarchaeota was found specially in the upper sample of mangrove sediment analysed whereas the Crenarchaeota was found specially in the lower. Based on the data obtained, it can be concluded that the vegetation is one of the factors affecting the structure of bacterial and archaeal communities in mangrove soils. Additionaly, the effects of edafic factors and seasonal variations have to be considered as determining the prokaryotic community sctuctures, and bacterial and archaeal communities can respond independently to the factors that determine their community structures. Bacterial diversity can vary with the studied estuarine ecosystem. Studies are necessary concerning to diversity of Bacteria, it variation and correlation with biogeochemical process in the mangrove and marisma soils. These soils show a great diversity of bacteria, much of than unknown, which represent a great genetic potential to the biotechnology.
Navarrete, Acácio Aparecido. "Estrutura e diversidade de comunidades microbianas em solos sob diferentes sistemas de uso da terra na Amazônia Ocidental". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-13102009-135502/.
Texto completoThe present study was part of a wider project of international cooperation entitled Conservation and Sustainable Management of Below-Ground Biodiversity CSMBGBD/ BiosBrasil, established by the United Nations Environment Programmer (UNEP) at the basin of Alto Solimões, Western Amazon, Amazonas State. This region is a remanescent territory of indigenous people and remains conserved, being considered an important hotspot of biodiversity. Even though, the studied areas were characterized by mosaic landscapes under different land use systems. Soil samples were collected in a period of high pluviometric index in the years 2008 and 2009 in areas characterized by tropical rainforest, semi permanent manioc cultivation under agricultural management of slash-and-burn, pasture established in the 1970s and forested areas at a higher stage of regeneration (>10 years abandoned). The samples were analyzed by DGGE, ARISA techniques, cloning and sequencing in order to obtain a characterization of the community structure of Archaea, Bacteria and microfungi and the composition and diversity of an archaeal functional group involved in the process of ammonia oxidation in the soil environments. The results allowed to conclude that land use has a great effect on the community structure of Archaea, Bacteria and microfungi present in the soil and suggest that long period of abandon of the areas is necessary to accomplish with the resilience of Amazonian ecosystems in the context of landscape recomposition. Additionally, the data revealed that richness and community diversity of ammonia oxidizing Archaea were able to sensitively reflect the changes observed in the soil environment due to deforestation of rainforest areas and subsequent use with traditional agriculture cultivation and pasture in the region of Alto Solimões, Western Amazon.
Lee, Sungeun. "Virus-host interactions across a soil pH gradient at the community and individual scale". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEC020.
Texto completoSoil viruses have potential to influence microbial community structure and subsequent ecosystem functioning by directly affecting the abundance of host cells by lysis and through their ability to transfer genes between hosts. Although our understanding of soil viral diversity and functioning has increased, the role of viruses and their interactions with prokaryotes in soil is limited. To gain a better understanding of virus-host interactions in soil, a long-term pH-manipulated soil gradient, which microbial community structure changes across, was investigated. The main objectives of this thesis were to 1) determine the influence of microbial community structure and soil pH on viruses using metagenomics and viromics (Chapter II), 2) determine the infectivity of soil viral populations from co-localized and foreign pH soil niches using a plaque assay approach combined with hybrid metagenomics sequencing (Chapter III) and 3) identify virus populations infecting specific soil microbial functional groups, specifically methanotrophs (Chapter IV) and nitrifiers (Chapter V), using DNA stable isotope probing combined with metagenomic deep sequencing. Viral community structure was found to change with soil pH, demonstrating that viral communities are tightly linked to host populations, but also may have narrow host ranges. Analysis of clustered regularly interspaced short palindromic repeats (CRISPR) arrays revealed dynamic virus-host interactions, with the number and size of CRISPR arrays distinct across contrasting pH soil. Profiling of the host-virus linkages between soil pH, suggests that viruses play a critical role in shaping the composition and function of the soil prokaryotic community. Surprisingly, greater infectivity of a host bacterium by virus populations was found when viruses and host bacterium were not co-localized in the same pH soil. Coevolutionary processes between the host and virus populations, such as restriction modification/virus-encoded methyltransferase and CRISPR-Cas system/spacer mutation, provide evidence for local adaptation, and that virus-bacterial host interactions play an integral part in the susceptibility of a host to infection and consequently in the regulation of soil bacterial populations. Targeting specific microbial functional groups via stable isotope probing allowed analysis of individual host-virus populations. Tracking carbon flow through prokaryotic and viral populations revealed active interactions between viruses and methanotroph and nitrifier hosts, and soil pH niche preferences. Evidence of horizontal gene transfer and virus-encoded auxiliary metabolic genes, such as glycoside hydrolase families, peptidases, particulate methane monooxygenase subunit C (pmoC), nitrogenase (nifH) and cytochrome cd1-nitrite reductase, supports that viruses are significant contributors to host functioning and carbon and nitrogen cycling in soil. Overall, this work demonstrated that soil viruses are important regulators of microbial communities through specific host lysis and dynamic virus-host interactions
Radomski, Nicolas. "Sources des mycobactéries non-tuberculeuses dans les bassins versants". Phd thesis, Université Paris-Est, 2011. http://pastel.archives-ouvertes.fr/pastel-00669399.
Texto completoArthur, Jennifer D., Noah W. Mark, Susan Taylor, J. Šimunek, M. L. Brusseau y Katerina M. Dontsova. "Batch soil adsorption and column transport studies of 2,4-dinitroanisole (DNAN) in soils". ELSEVIER SCIENCE BV, 2017. http://hdl.handle.net/10150/624067.
Texto completoNunes, Gisele Lopes. "Diversidade e estrutura de comunidades de Bacteria e Archaea em solo de mangue contaminado com hidrocarbonetos de petróleo". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-23032007-162450/.
Texto completoThe impacts of petroleum hydrocarbon pollution on the diversity and functionality of the microbial communities in mangrove soils are not totally understood, mainly due to the methodological limitations to access unculturable microorganisms. However, several cultureindependent molecular methods have been used to investigate the diversity and structure of microbial communities in natural ecosystems. The aim of this work was to evaluate shifts in Bacteria and Archaea community structures and the diversity of Bacteria in a soil transection of the Iriri river mangrove (Bertioga, SP) showing a petroleum hydrocarbon contamination gradient. The analyses by denaturing gradient gel electrophoresis (DGGE) showed that the communities of Bacteria and Archaea in different geographical positions were more similar among them than the communities in different depths along the soil profile at the same geographical position. Sequence analyses of bacterial 16S rDNA clones from different points sampled in April 2000 showed that the genetic diversity of the bacterial communities, based on the Shannon index, differ statistically only between P1 (less polluted) and P3 (more polluted) locations. Nonparametric estimates of species richness showed that P1, P2 and P3 may have more than 3539, 2524 and 1421 bacterial species, respectively. For P2 sampled in years 2000 and 2004, even though the Shannon indices were similar, there was a probable dominance of specific bacterial groups in year 2004, based on the high values of the reciprocal of Simpson\'s index. The data also showed that the estimated number of bacterial species in P2 decreased with the time, being lower in samples collected in 2004, as compared to samples collected in 2000. In the general, the phylogenetic affiliation of the 16S rDNA clones showed high bacterial species diversity, and most of the bacteria were of unknown species. The data suggest that the contamination of Iriri river mangrove soil with petroleum hydrocarbon is selecting microorganisms more adapted to the introduced carbon sources into the soil.
Gruber, Helga [Verfasser], Martin Akademischer Betreuer] Müller, Heinrich H. D. [Akademischer Betreuer] [Meyer y Karl [Akademischer Betreuer] Kramer. "Surveillance of Cry1Ab protein and cry1Ab DNA in liquid manure, soil and agricultural crops under Bt-maize cropping and slurry management of cows fed Bt-maize (MON810) / Helga Gruber. Gutachter: Karl Kramer. Betreuer: Martin Müller ; Heinrich H. D. Meyer". München : Universitätsbibliothek der TU München, 2011. http://d-nb.info/1019590017/34.
Texto completoKapusuz, Derya. "Sol-gel Synthesis Of Dna Encapsulated Silica". Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610627/index.pdf.
Texto completoAnderson, Dominique Elizabeth. "Gene Discovery in Antarctic Dry Valley Soils". Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6598_1265941858.
Texto completoThe metagenomic approach to gene discovery circumvents conventional gene and gene product acquisition by exploiting the uncultured majority of microorganisms in the environment. It was demonstrated in this study that metagenomic methods are suitable for gene mining in extreme environments that harbor very high levels of unculturable microorganisms. DNA was extracted from Antarctic mineral soil samples taken from the Miers Valley, Antarctica. The metagenomic DNA was also used to construct a fosmid library comprising over 7900 clones with an average insert size of 29 kb. PCR amplification using bacterial and archaeal 16S rRNA gene specific primers and subsequent denaturing gradient gel electrophoresis (DGGE) of bacterial 16S rDNA amplicons showed that a small percentage of bacterial diversity (>
1%) was captured in the metagenomic fosmid library. Activity-based screening for lipase and esterase genes using a tributyrin plate assay yielded twelve positive clones. LD1, a putative, novel cold-active GDSL lipase/esterase was identified and sequenced. The C-terminal domain of the ORF was found to be an autotransporter similar to those associated with type V secretion systems in Gram negative bacteria. Sub-cloning of the gene resulted in lipolytic activity in E. coli. Preliminary enzyme assays have determined that LD1 hydrolyses p-nitrophenyl esters with chain lengths shorter than C10, an indication that the enzyme is an esterase. Complete purification and characterisation of this enzyme is subject to further study.
van, Woerkom Anne. "Ancient DNA from soils and sediments from the Krigstjärn area, northern Sweden : Preservation and detection of Holocene mammal sedaDNA". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-127680.
Texto completoCristea, Pop Casandra Ioana <1978>. "Minori rumeni tra percorsi migratori e rappresentazioni. Nè soli, nè accompagnati a Bologna". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/732/.
Texto completoBarroso, Haline. "Análise de metilação de DNA nos genes da citoqueratina 14 (KRT14) e 19 (KRT19) em amostras de pele exposta e não exposta ao sol". Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/9427.
Texto completoMade available in DSpace on 2017-09-05T14:37:36Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 798401 bytes, checksum: 41671bb8b384bd28413ef4c5851e99ce (MD5) Previous issue date: 2015-02-27
It is well established that solar UV radiation can cause mutations in DNA and increase the risk of developing skin cancer. However, little is known about the ability of UV radiation to cause epigenetic changes in the skin. DNA methylation, characterised by the addition of a methyl group in cytosines within CpG dinucleotides, can modify gene transcription, leading to decreased expression or even silencing of a gene. Epigenetic changes could represent an important pathway by which environmental factors influence aging and disease risks, with a tissue-specific manner. Epithelial keratins are called cytokeratins, the main function of cytokeratins is to maintain the integrity and mechanical stability through cell-cell contacts with epithelial tissue. The aim of this study was to investigate the sun exposure influence on DNA methylation status in the cytokeratin 14 (KRT14) and 19 (KRT19) genes of skin cells of subjects whithout history of skin disease. Skin biopsies were obtained by punch of sun-exposed (outer forearm) and sun-protected areas (inner arm) from 30 corpses of the Brazilian Services of Death Investigation. The KRT14 gene DNA methylation analysis was performed using Methylation-Specific PCR (MSP), and the KRT19 gene DNA methylation analysis was performed using Methylation-Sensitive Restriction Enzymes (MSRE) of sun-exposed and sun-protected skin areas. Statistical analysis showed no significant differences between sun-protected and sun-exposed areas and the most frequently methylated condition for CpG studied for KRT14 and KRT19 genes (p> 0.05; McNemar). We conclude that sun exposure does not induce changes in DNA methylation status in the KRT14 and KRT19 genes.
Pesquisas tem mostrado que a radiação UV do sol pode causar mutações no DNA e aumentar o risco para o desenvolvimento de câncer de pele. Entretanto, ainda pouco se sabe sobre a capacidade da radiação UV em causar alterações epigenéticas na pele. A metilação do DNA é caracterizada pela adição do grupo metil em uma citosina precedida por uma guanina (dinucleotídeo CpG), o que pode alterar a transcrição gênica, diminuindo a expressão ou silenciando um gene. Alterações epigenéticas podem representar um importante caminho de como os fatores ambientais influenciam no envelhecimento e no desenvolvimento de certas doenças de maneira tecido específica. Queratinas epiteliais são chamadas de citoqueratinas, e sua principal função é manter a integridade e estabilidade mecânica do tecido epitelial. Neste trabalho investigamos se há influência da exposição solar sobre o perfil de metilação de DNA nos genes das citoqueratinas 14 (KRT14) e (KRT19), em células da pele de indivíduos sem histórico de doenças de pele. Biopsias de pele foram obtidas através de um Punch circular da de área exposta e não exposta ao sol de 30 cadáveres do Serviço de Verificação de Óbito. A análise de metilação do gene KRT14 foi realizada pelo método de PCR Específica para Metilação (MSP), e para o gene KRT19 foi realizado o método de Restrição Enzimática Sensível à Metilação (MSRE) das áreas expostas e protegidas do sol. A análise estatística mostrou que não há diferenças significativas entre as regiões exposta e não exposta ao sol, sendo a condição metilada a mais frequente tanto para o gene KRT14 quanto para o gene KRT19 (p>0,05; McNemar). Assim, concluímos que não há influência da exposição solar no perfil de metilação de DNA nos genes KRT14 e KRT19.
Arthur, Jennifer y Jennifer Arthur. "The Investigation of the Environmental Fate and Transport of 2,4- dinitroanisole(DNAN) in Soils". Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/623164.
Texto completoDelgado, de la flor Yvan A. "Spider and Beetle Communities across Urban Greenspaces in Cleveland, Ohio: Distributions, Patterns, and Processes". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587656050129337.
Texto completoOlivares, Martinez Christopher Ignacio. "Environmental Fate, (Bio)transformation, and Toxicology of 2,4-dinitroanisole (DNAN) in Soils and Wastewater Sludge". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/596139.
Texto completoGianfrancesco, Richard Umberto. "Phosphorus nutrition of mycorrhizal and non-mycorrhizal plants of upland soils with special reference to the utilization of the phosphodiester DNA under sterile conditions". Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299580.
Texto completoSivander, Malin. "Din sol, din himmel, dina ICA-butiker röda : om hur Sverige framställs i ICA:s reklamfilmer". Thesis, Stockholms universitet, Institutionen för mediestudier, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-113107.
Texto completoRábová, Petra. "Využití testů s destruenty pro ekotoxikologické hodnocení kvality půd". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433143.
Texto completoMarlin, Constanze von. "Public Art Space : zum Öffentlichkeitscharakter der Minimal Art : Carl Andre - Dan Flavin - Donald Judd - Sol LeWitt - Robert Morris /". Weimar : Verlag und Datenbank für Geisteswissenschaften, 2008. http://aleph.unisg.ch/hsgscan/hm00227183.pdf.
Texto completoHasegawa, Aline Yuri. "Um dia de sol para encontrar os antepassados : o Shokonsai como estudo de caso do Obon no Brasil". reponame:Repositório Institucional da UFABC, 2018.
Buscar texto completoCoorientadora: Profª. Drª. Adriana Capuano de Oliveira
Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciências Humanas e Sociais, Santo André, 2018.
Esta pesquisa trata do Shokonsai, um rito de culto aos ancestrais realizado no município de Álvares Machado, há 99 anos, em um cemitério étnico de nikkei. Além das peculiaridades do local e da longevidade do evento, um fator climático também é mobilizado no discurso do público: nos registros e nas narrativas orais, jamais choveu ao longo do dia e, durante o espetáculo de acendimento de velas, os ventos cessam de soprar e somente retornam após a última apagar-se naturalmente. Por meio de obervação participante, pretendo dar conta da descrição e análise das práticas dos interlocutores que articulam fenômenos climáticos à vontade dos mortos. Essa prática ritualística levanta questões identitário-étnicas, que se conectam a processos históricos nacionais japoneses e brasileiros, de modo que se faz necessário também compreender como os discursos de pertencimento étnico contemporâneos mobilizam elementos raciais e culturais de cada contexto.
This research approaches the Shokonsai, an ancestor worship rite performed in Álvares Machado since 1918, in an ethnic Nikkei cemetery. In addition to the peculiarities of the place and the longevity of the event, a climate factor is also mobilized in the public discourse: according to the records and oral narratives, it never rained during the day, and during the candlelight show the winds have ceased to blow and have only returned after the last candle is put out naturally. Through participant observation, I intend to describe and analyze the practices of the interlocutors who articulate climate phenomena to the will of the dead. This ritual practice raises some ethnic and identity issues, which necessarily connect to Japanese and Brazilian national historical processes. In that sense, it is also necessary to understand how contemporary discourses about ethnic belonging mobilize racial and cultural elements of each context.
Marlin, Constanze von. "Public - art - space zum Öffentlichkeitscharakter der Minimal Art ; Carl Andre, Dan Flavin, Donald Judd, Sol LeWitt und Robert Morris". Weimar VDG, 2005. http://d-nb.info/985889950/04.
Texto completoMarlin, Constanze von Andre Carl Flavin Dan Judd Donald LeWitt Sol Morris Robert. "Public - Art - Space : zum Öffentlichkeitscharakter der Minimal Art ; Carl Andre, Dan Flavin, Donald Judd, Sol LeWitt und Robert Morris /". Weimar : VDG, Verl. und Datenbank für Geisteswiss, 2007. http://www.gbv.de/dms/weimar/toc/547381905_toc.pdf.
Texto completoOliver, Fojkar. "Azotofiksirajuće cijanobakterije u zemljištima Vojvodine i njihova ultrastrukturna i genetička karakterizacija". Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=101459&source=NDLTD&language=en.
Texto completoIn this study examined is the frequency of nitrogen-fixing cyanobacteria, total number of algae and total number of bacteria in different soil types on eleven localities in the Vojvodina Province. Seven out of those eleven localities are found in protected nature reserves. Actually, studied was the number of the cyanobacteria and algae depending on the depth of pedological characterization as well as on season. First, isolated were the types of nitrogen-fixing cyanobacteria, determined was their taxonomic origin and basic cytological characteristics. Also examined was the ultrastructure of vegetative cells, heterocysts and other outer structures on fimbriae and pili cells using TEM, transmission electron microscope. Finally, performed was the genetic characterization of isolated types of nitrogen-fixing cyanobacteria using the PCR method and analyzing STRR fragments of DNA.The presence of nitrogen-fixing cyanobacteria and total number of algae was significantly higher with hydromorphic and halomorphic soils than with authomorphic ones. Highest annual average number of nitrogen-fixing cyanobacteria in the topsoil (0-5 cm) was reported with fluvisol soil in Special Nature Reserve „Koviljsko petrovaradinski rit” (Swamp) and there were 150864 units of bacteria per gram of absolutely dry soil. The soil with the lowest presence of nitrogen-fixing cyanobacteria recorded was cambisol in National Park “Fruska gora” with 1582 units per gram of soil in the topsoil.With all the researched types of soils the number of nitrogen-fixing cyanobacteria was in the topsoil, 0-5 cm of depth and decreased in line with the depthof soil and lowest was at the deepest layer, 30-60cm. The highest frequency of nitrogen-fixing cyanobacteria was found during the winter season with most of the examined soils. Nitrogen-fixing cyanobacteria are the dominant type of bacteria in our soils and are presented with 56, 27% compared to other types of algae.30 strains of nitrogen-fixing cyanobacteria were isolated: 19 types of Nostoc sp., 4 of Anabaena sp. and one in each genus of Calothrix, Tolypothrix and Phormidium.Using ultrastructural examination and TEM microscope when studying vegetative cells of nitrogen-fixing cyanobacteria observed were the inclusions of regular frequency: carboxysomes (Cs), cyanophycin granules (CG) , polyphosphate granules (PG), ribosomes (R), lipid granules (SS -granule ) and thylakoids ( T ) as well as the inclusion of irregular occurrence: a membrane-bound crystal inclusions.Using TEM technique and staining the cells with the RR and ultra thin cross section, we determined the presence of depletion of the fimbriae with three strains (A.314, A.azollae and N.302) and typical fimbriae with the two strains (N.311 and N.9229). Applying the method of negative staining NS PTA also noticed were a typical fimbriae, needle-hairy like looks with clear boundaries with the three strains (N.302, N.7901, N.9229). However, also observed were atypical mucous fimbriae, which do not have clearly expressed borders, but they are very strongly spread around the vegetative cells, with the three strains (A.314, A.azollae, N.311).With symbiotic - infective strains N.7901 and N.9229 only typical fimbriae of first class occurred, and in diazotroph strains and symbiotic – non infectious strain A. azollae found were atypical mucous fimbriae of second class.To test the similarity of cyanobacteria by PCR method and using a STRR - conservative DNA sequence of the genome used were 39 strains fixing cyanobacteria and with 38 established was their presence. All strains can be divided into three groups of clusters. The first cluster is the largest and covers 24 strains, and is divided into two subclusters: Ia which includes 12 strains,where predominant are Nostoc strains ( 8 ) , and subcluster Ib , which also implies 12 strains , out of which 6 strains belong to the genus Anabaena. Subcluster Ia and Ib show a difference of 90 %. All three symbiotic , infectious Nostoc strains are classified in a cluster I: N.7901, N.9229 and N. 8001. Each symbiotic Nostoc strain has a genetic similarity with one di-nitrogen Nostoc strain isolated from a lot of different soils in Vojvodina.Cluster II includes seven (7) strains , including strains among which the predominant are Cylindrospermum ones , while cluster III includes 7 strains of which 6 belong to the genus Nostoc and one to genus Rivularia.Detailed knowledge of the properties of isolated fixing cyanobacteria could contribute to their future application both in the production of field crops and vegetables, as well as in biotechnological production.
Sow, Mamadou Dia. "Rôle fonctionnel de l'épigénétique (Méthylation de l’ADN) dans la réponse du peuplier à des variations de disponibilité en eau du sol". Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE3046.
Texto completoForest decline has been observed around the world due to climate change. As sessile and long-lived organisms subject to repeated environmental constraints, trees need to develop strategies enabling them to cope with fluctuating environmental conditions. Epigenetic mechanisms have recently emerged as a valuable source of flexibility for adaptation to climate changes.This thesis aimed to evaluate the role of epigenetics (DNA methylation) in poplar, in response to drought, at three time scales: at short term (developmental plasticity), middle term (memory, priming) and long term (adaptation). These studies focused on meristems which are the center of morphogenesis.The main results are : i) DNA methylation is affected during drought stress in meristems, ii) Induced-DNA methylation variations are stable in time, iii) DNA methylation could be used as a genetic marker for populations differentiation under drought, iv) DNA methylation in CG and in a lesser extent in CHG contexts could be used as a marker of individuals and/or populations differentiation like the genetic markers, v) Hypomethylated poplar trees (RNAi DDM1) are more tolerant to drought and show a pathogens responsive phenotype suggestive of enhanced resistance, vi) DNA methylation could alter hormonal balance and promotes priming, vii) Decrease in DNA methylation level (RNAi DDM1) favors the reactivation of transposable elements and their integration in new genomic regions during the drought stress leading to genome instability.These results propose a role of DNA methylation at the interface between the physiological response (hormonal response) and the genetic variation under environmental constraints. These works open up new perspectives in Breeding and forest conservation management, particularly in the frame of the ANR EPITREE project