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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Variabilidade genética de germoplasma de arroz (Oryza sativa L.) para tolerância ao frio na germinação / Genetic variability in the rice (Oryza sativa L.) germoplasm of Embrapa using molecular and morphological markers

Monzón, Daisy Leticia Ramirez 01 April 2015 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-10-03T17:03:34Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) TESE_DAISY.pdf: 1476557 bytes, checksum: 5aac230c9e30648ef15fe68b6cb95e14 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-10-06T20:40:31Z (GMT) No. of bitstreams: 2 TESE_DAISY.pdf: 1476557 bytes, checksum: 5aac230c9e30648ef15fe68b6cb95e14 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-06T20:40:31Z (GMT). No. of bitstreams: 2 TESE_DAISY.pdf: 1476557 bytes, checksum: 5aac230c9e30648ef15fe68b6cb95e14 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-04-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / No estado do Rio Grande do Sul as temperaturas baixas são um dos principais fatores limitantes à cultura do arroz, sendo a tolerância ao frio uma característica de difícil seleção em condições de campo. A utilização de marcadores moleculares SSR combinados com características fenotípicas fornecem informações completas e precisas, permitindo ao melhorista selecionar de maneira mais eficiente genótipos úteis para os programas de melhoramento. Sendo assim, o objetivo foi estudar a variabilidade genética dos genótipos pertencente ao banco ativo do germoplasma do arroz da Embrapa, utilizando caracteres morfológicos e marcadores moleculares SSR para a identificação de variabilidade para tolerância ao frio na germinação. A resposta dos genótipos para estresse por frio na germinação foi avaliada em dois experimentos; I: 124 genótipos de arroz e quatro testemunhas tolerantes foram avaliados em condição de temperaturas de 13C por 28 dias e 25C por sete dias; foi comparado seu desempenho relativo, medido pelo comprimento do coleóptilo, comprimento de raiz, comprimento de parte aérea e germinação. II: sob oscilação de temperatura de: 25ºC, durante 72 horas, 13ºC por 96 horas (frio) e novamente 25ºC por 72 horas (controle) para diferenciar genótipos quanto à tolerância ao frio por meio do recrescimento do coleóptilo. Foram avaliados 151 genótipos e nove locus SSR. Os resultados obtidos indicaram que entre os genótipos estudados do banco de germoplasma da Embrapa existe ampla variabilidade genética, assim como diferentes respostas ao estresse. Assim, alguns genótipos possuem potencial para serem utilizados na ampliação da base genética em programas de pré-melhoramento e melhoramento da cultura. Com base na caracterização fenotípica, os genótipos mais promissores para cruzamentos e obtenção de progênies superiores quanto à tolerância ao frio são BRS 7-Taim, Rio Grande, EEA 405. Na caracterização genotípica, os genótipos em estudo apresentaram grande variabilidade genética. / At the Rio Grande do Sul State low temperatures are one of the main limiting of rice crop, being the cold tolerance a characteristic of difficult selection on field conditions. The utilization of SSR molecular markers combined with phenotypic characteristics provides complete and precise information, enabling the breeder to select more efficiently useful genotypes to the breeding programmes. Therefore, the aim of this work was to study the genetic variability of the genotypes belonging of the rice germoplasm active bank of Embrapa, using morphological characters and SSR molecular markers, to identify the genetic variability in cold tolerance at the germination. The response of the genotypes to cold stress during the germination was evaluated in two experiments; I: 124 rice genotypes and four tolerant controls were evaluated on conditions of temperature of 13 ºC during 28 days and 25 ºC during seven days; there were compared their relative performance, measured by the length of the coleoptile, root and shoot, and germination. II: under oscillation of temperature of 25 ºC during 72 hours, 13 ºC during 96 hours (cold) and again 25 ºC during 72 hours (control) to differentiate the genotypes in terms of cold tolerance by the regrowth of the coleoptiles. There were evaluated 151 genotypes and nine SSR loci. The results obtained indicated that among the studied genotypes of the germoplasm bank of Embrapa, there are broad genetic variability, as well as different stress responses. Then, some genotypes have the potencial to be used in the expansion of the genetic basis in the pre-breeding and breeding programmes of this crop. Based on the phenotypic characterization, the most promising genotypes to cross and obtain superior progenies in terms of cold tolerance were BRS 7-Taim, Rio Grande and EEA 405. In the genotypic characterization, the genotypes in study showed high genetic variability.
112

Caracterização molecular de recursos genéticos de Cucurbita argyrosperma, Cucurbita ficifolia e Cucurbita pepo. / Molecular characterization of genetic resources of Cucurbita argyrosperma, Cucurbita ficifolia and Cucurbita pepo.

Priori, Daniela 25 February 2011 (has links)
Made available in DSpace on 2014-08-20T14:06:16Z (GMT). No. of bitstreams: 1 Dissertacao_Daniela_Priori.pdf: 1667098 bytes, checksum: 34e76681ceb9a2d408f534549b9ee012 (MD5) Previous issue date: 2011-02-25 / Genetic resources conserved in genebanks have a great value in terms of conservation of rare types, when they are threatened by abandonment of farming or as a unique resource for plant breeding programs. Among the accessions conserved in genebanks important sources of genetic variability can be found for obtaining more productive genotypes tolerant to biotic and abiotic stresses and improved nutritional quality. To have success in that demand is necessary that the accessions contained in genebanks are characterized and evaluated in terms of both qualitative and quantitative characters. The characterization and evaluation of accessions conserved in genebanks must be priorities in the strategy for management of genetic resources, as they provide better knowledge of the germplasm available, is essential for use in breeding programs. In Brazil, there is little information on genetic resources of Cucurbits, especially as regards Cucurbita ficifolia, Cucurbita argyrosperma. Large number of Cucurbita landraces grown in the country could be better exploited as sources of genes for breeding programs, after genetic characterization. Much of the genetic diversity of different Cucurbita landraces grown in southern Brazil has been lost due to neglect of cultivation or its replacement by commercial hybrid varieties. This work was carried in order to contribute to general knowledge related to genetic resources of Cucurbita argyrosperma, Cucurbita ficifolia and Cucurbita pepo, and with specific objectives to assess the transferability of primers designed to C. pepo in C. argyrosperma and C. ficifolia and to evaluate the genetic variability within and among landraces of C. pepo grown in Rio Grande do Sul through analysis of microsatellite markers. Ten accessions of C. pepo, nine of C. argyrosperma and five of C. ficifolia belonging to the Active Germplasm Bank of Cucurbitaceae from Embrapa Temperate Agriculture were submitted to molecular characterization. The genetic distance between these accessions was determined. The transferability of SSR loci from C. pepo to C. argyrosperma and C. ficifolia was 85% and 80% respectively. The analysis of these 24 accessions with 35 loci generated a total of 105 SSR markers, ranging from one to four alleles per locus, of which 56 (53,33%) were polymorphic, showing that there is genetic diversity in the accessions analyzed. The presence and absence of markers allowed to find 100 loci, varying from one to five alleles per locus, with overall average of three alleles per marker analyzed. Among the 34 loci tested, 29 (85.2%) were polymorphic, showing that there is genetic variability among the accessions of C. pepo analyzed. Data evaluation was done by molecular analysis of molecular variance (AMOVA). It was observed that 54.60% of genetic variability is attributable to variation between accessions and 45.39% is attributed to differences within accessions. A comparative analysis was made between the ten accessions studied, analyzed two by two by AMOVA. From 45 comparisons between the ten accessions significant differences there were detected between 35 comparisons, with average of 57.10% of molecular variation attributed to differences between accessions. Genetic variation among counties where the accessions were collected was not significant, indicating that there is not population subdivision according to geographic region. Results indicate that the microsatellites were efficient for the characterization and molecular analysis of genetic divergence. These studies contributed to increase the knowledge related to these genetic resources. SSR primers developed for Cucurbita pepo can be used for molecular characterization of C. argyrosperma and C. ficifolia. Landraces of C. argyrosperma and C. ficifolia showed low genetic variation, while C. pepo shows great variability. The largest proportion of variability in C. pepo is distributed between accessions and not within accessions. / Os recursos genéticos conservados em bancos de germoplasma apresentam grande valor do ponto de vista da conservação de tipos raros, quando os mesmos são ameaçados pelo abandono do cultivo ou como recurso insubstituível para programas de melhoramento genético vegetal. Dentre os acessos contidos nos bancos de germoplasma podem ser encontradas importantes fontes de variabilidade genética para a obtenção de genótipos mais produtivos, tolerantes a estresses bióticos e abióticos e com melhor qualidade nutricional. Para que haja sucesso nessa demanda é necessário que os acessos contidos nos bancos de germoplasma sejam caracterizados e avaliados, tanto em termos de caracteres qualitativos quanto quantitativos. No Brasil, há pouca informação sobre os recursos genéticos de Cucurbitáceas, de modo especial no que se refere à Cucurbita argyrosperma e Cucurbita ficifolia. Grande número de variedades locais de Cucurbita cultivadas no país poderiam ser melhor exploradas como fontes de genes para programas de melhoramento, após a devida caracterização. Muito da diversidade genética das variedades locais de diferentes espécies de Cucurbita cultivadas no Sul do Brasil vem sendo perdida devido ao abandono do cultivo ou à sua substituição por variedades híbridas comerciais. Este trabalho foi realizado com o objetivo geral de contribuir para o conhecimento relacionado aos recursos genéticos de Cucurbita argyrosperma, C. ficifolia e C. pepo, e objetivos específicos de avaliar a transferibilidade de loci de microssatélites de C. pepo para C. argyrosperma e C. ficifolia; e avaliar a variabilidade genética entre e dentro de variedades locais de C. pepo cultivadas no Rio Grande do Sul por meio da análise de marcadores microssatélites. Foram analisados dez acessos de C. pepo, nove de C. argyrosperma e cinco de C. ficifolia do acervo do Banco Ativo de Germoplasma de Cucurbitáceas da Embrapa Clima Temperado. A distância genética entre esses acessos foi determinada. A transferibilidade de locos SSR de C. pepo para C. argyrosperma e C. ficifolia foi de 85% e 80%, respectivamente. A análise dos 24 acessos de Cucurbita por meio de 35 loci SSR gerou um total de 105 marcadores SSR, com variação de um a quatro alelos por loco, dos quais 56 (53,33%) foram polimórficos, evidenciando que há diversidade genética entre os acessos analisados. Através dos dados de presença e ausência de marcadores obtidos com 34 combinações de primers, foram encontrados 100 locos com variação de um a cinco alelos por loco, com média geral de três alelos por marcador analisado. Dentre os 40 locos analisados, 29 (85,3%) foram polimórficos, evidenciando que há variabilidade genética entre os acessos de C. pepo analisados. A avaliação dos dados moleculares foi feita pela análise molecular da variância (AMOVA). Deste modo, foi possível verificar que 54,60% da variabilidade genética é atribuída à variação entre acessos e 45,39% é atribuída a diferenças dentro dos acessos. Foi feita a análise comparativa entre os dez acessos estudados, analisados dois a dois, pela análise AMOVA. Das 45 comparações entre os dez acessos, foram significativas as diferenças entre 35 delas, com média de 57,10% da variação molecular atribuída às diferenças entre acessos. A variação genética entre os municípios onde os acessos foram coletados não foi significativa, indicando que não ocorre subdivisão de populações em função da região geográfica. Os resultados obtidos indicam que os microssatélites foram eficientes para a caracterização molecular e a análise da divergência genética. É possível utilizar primers de microssatélites desenvolvidos para C. pepo na caracterização molecular de C. argyrosperma e C. ficifolia. Variedades locais de C. argyrosperma e C. ficifolia apresentam pouca variabilidade genética, enquanto que C. pepo evidencia grande variabilidade genética. A maior proporção da variabilidade em C. pepo encontra-se distribuída entre os acessos, e não dentro dos acessos.
113

Microstructure And Mechanical Properties Of Consolidated Magnesium Chips

Anil Chandra, A R 08 1900 (has links) (PDF)
Development of sustainable manufacturing and conservation of primary materials are the key challenges to environmental degradation and climate change. Recycling of primary materials is one of the approaches suggested for sustainable green manufacturing. In the present study, an attempt has been made to encompass both these concepts, i.e. recycling of waste machined chips of magnesium and development of sustainable manufacturing process. Chips generated during machining operations are of significant importance; they dissipate the heat from the work-piece and control the quality of the finished products. In recent years researchers have shown that by controlled machining it is possible to tailor size, shape and microstructure of chips and this has added new dimensions to the utility of these machined chips. Chips in the form of thin strips, rods, very fine powders with varying aspect ratio have been successfully machined with grain structure having nano size (~80nm) to submicron size. Consolidation of such machined chips and subsequent fabrication of products is of great interest from the point of view of sustainable manufacturing. Consolidation of machined chips by cold compaction followed by hot extrusion was proposed and has been termed as solid state recycling (SSR). This alternative method of manufacturing using machined chips circumvents melting and casting. Although several materials have been tried by this route, magnesium appears to be the most investigated material. Being lightest among the structural materials, magnesium and its alloys have wide ranging applications especially in automotive industry. Further, magnesium melting is cumbersome and environmentally hazardous which necessitates researchers to explore methods of overcoming the melting route. In this pursuit, SSR appears to be a choice for a soft material like magnesium whose products are fabricated by conventional processing techniques which include cold compaction followed by hot extrusion. Most of the work in literature with regard to SSR of magnesium has been centered around development of new alloys and their characterisation at room and elevated temperatures. Effect of oxide contaminants has also been widely studied. However, studies on microstructural evolution during processing (i.e. microstructure prior to and after extrusion) have not been reported. Further, such studies with pure metal is important since it is possible to separate the effect of secondary phases including precipitates which are otherwise present in alloys of Mg. Hence, commercial grade pure magnesium is the material of interest in the present work. Process of consolidation includes room temperature compaction followed by hot extrusion. The aim of the present work includes: Consolidation of machined chips of magnesium into billets by cold compaction at room temperature followed by hot extrusion, Microstructural characterisation of these cold compacted billets prior to and after extrusion, Evaluation of mechanical properties after extrusion at different temperatures. Correlating the mechanical properties with microstructure. In the present study mechanical properties evaluated include: strength properties (hardness, tensile and compressive properties), and damping properties As-cast billet of pure magnesium was turned in a lathe to produce chips at ambient conditions. The chips were cold compacted into billets of 28 mm diameter at a pressure of 350 MPa and held for 30 minutes. The billets of compacted chips (referred here as CC) were later extruded at four different temperatures, viz. 250, 300, 350 and 400°C, with an extrusion ratio of 49:1. Prior to extrusion, the CC was soaked at the desired extrusion temperature for 1 hour. Here, extrusions of compacted chips are designated as CCE (chip compacted and extruded). For comparison, the as-cast billet was extruded under similar conditions and is designated as AE (as-cast and extruded). The extruded rods had a diameter of 4 mm. Microstructural characterisation was done prior to and after extrusion, which forms the first part of the thesis. The extruded rods were characterised for their room temperature strength properties in the second part of the thesis. In the third and last part, damping properties were characterised as a function of time and temperature. Microstructural changes at the end of temperature sweep tests were also examined. Optical microscopy did not reveal the grain structure of CC due to the intense strains associated with chip formation and subsequent cold compaction. However, chip boundaries were found randomly oriented and tri-junctions were found to be porous. The CC showed a relative density of 95.4% and this happens to be the highest amongst the values reported in literature for SSR machined chips. TEM images of CC revealed an average grain size of 0.75µm. Synopsis CCs were soaked at extrusion temperature and quenched to unravel the microstructure that exists prior to extrusion. Grain size and hardness measurements indicate that the material was recrystallised prior to extrusion. Bulk texture estimated from X-ray diffraction, showed weak crystallographic textures. The CC had a typical texture with c-axis aligned along the compaction direction which subsequently got randomised during soaking (pre-heating at extrusion temperature). After extrusion, the 250°C extruded AE had slightly stronger texture than CCE: with clear preference for < 1010 > and < 1120 > plane normals. High working temperatures removed such preference and made the textures randomised for both AE and CCE. In-grain misorientations and the relative presence of the twins, estimated from EBSD scans show a clear pattern for higher in-grain misorientations in CCE compared to AE. The values for AE at higher extrusion temperatures approached that of fully recrystallised magnesium. Higher twin fraction in AE was attributed to its relatively larger grain size compared to CCE. The chip boundaries that were randomly oriented before extrusion appeared aligned along the extrusion direction after extrusion. On the contrary AE had an equiaxed structure. Both longitudinal and transverse section micrographs showed pronounced chip boundaries in the 250°C extruded CCE while it was no so pronounced in the case of 400°C extruded material. Density measurements showed 98.6% relative density for 250°C extruded CCE as compared to 99.9% densification achieved in 400°C extruded CCE. Dislocation density estimated using Variance method from the peaks of the X-ray diffraction data showed higher values for CCE compared to AE. Dislocation density reduced with increase in extrusion temperature. For comparison extruded rods were annealed at 250°C for 2 hours and their dislocation density was estimated. Vickers hardness indentations were done at low load (25g) and higher load (200g). Both showed decreasing values with increase in extrusion temperature. Grain size dependent hardness variation followed the Hall-Petch relationship. CCE showed higher hardness compared to AE. Room temperature tensile test showed higher 0.2% tensile proof stress (TPS) in CCE material and obeyed the grain size dependent Hall-Petch relationship, though the strain to failure was poor. CCE extruded at 250°C showed fibrous fracture surface and was different from the rest of the CCEs with evidence of shearing at chip boundaries before fracture. Synopsis The rest of the CCEs had a typical fracture surface which was similar to AE material. Strain hardening behaviour, measured in terms of hardening exponent (n), hardening capacity (Hc) and hardening rate (θ) was quiet different for CCE compared to AE. Room temperature compression test showed different kind of failure for 250°C extruded CCE with longitudinal splitting (de-bonding at chip boundaries) and shearing at an angle to loading direction. The rest of the CCEs failed in a typical manner similar to AE material. The 0.2% compressive proof stress (CPS) as a function of grain size obeyed the Hall-Petch relationship for AE while the fit was not so good for CCE. Moreover, except 400°C extruded CCE (CPS was higher by ~22%) the rest of the CCEs had lower CPS compared to AE despite having finer grain size. This was contrary to the TPS and hardness findings wherein CCE was consistently higher compared to AE owing to grain refinement. Density measurements showed presence of 1.4%, 0.8% and 0.5% porosity in 250°, 300° and 350°C extruded CCE samples respectively. Prompted by density, hardness and TPS findings, the CPS values were back-calculated using the Hall-Petch relationship of AE. The back-calculated CPS values of CCE were higher than corresponding AE. Strength asymmetry, measured as a ratio of compressive proof stress to tensile proof stress was higher in CCE compared to AE. Damping capacity (tanφ) and dynamic modulus were determined as a function of time (tested upto 30 minutes) and temperature (from RT to 300°C) at a constant frequency (5 Hz). CCE material displayed higher tanφ during time and temperature sweep tests (by 10-15%) with CCE extruded at 250° showing the highest values. Dynamic modulus was comparable for both the materials (with less than 5% difference) though, modulus was higher in materials extruded at higher temperature. Microstructural changes were examined at the end of temperature sweep test, both at the point of loading and away from the point of loading. A significant grain growth was observed in region under the loading point (in a 3-point bending set-up) and was insignificant at regions away from the loading point. Coarsening was low in CCE material on account of suppression at chip boundaries. Microstructure of CCE and AE specimens subjected to similar heating conditions but without loading showed no such coarsening.
114

Diverg?ncia gen?tica em acessos de Psidiumguajava e avalia??o da resist?ncia de h?brido interespec?fico de Psidium ao nemat?ide Meloidogyne enterolobbi

Costa, Soniane Rodrigues da 25 January 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2015-11-11T23:45:15Z No. of bitstreams: 1 Disserta??o Soniane.pdf: 4275209 bytes, checksum: ccb64680a02e7e062aaddf493949e519 (MD5) / Made available in DSpace on 2015-11-11T23:45:15Z (GMT). No. of bitstreams: 1 Disserta??o Soniane.pdf: 4275209 bytes, checksum: ccb64680a02e7e062aaddf493949e519 (MD5) Previous issue date: 2013-01-25 / The objectives of this study were to obtain and evaluate interspecific hybrids of the genus Psidiumto resistance to M. enterolobii and analyze the genetic variability of accessions of guava and ara?azeiros of the active germplasm bank of Embrapa Semi-Arid based on microsatellites, to guide genetic resources and breeding programs, emphasizing crosses of guava with other Psidium species.The crosses were performed when the calyx ruptured on the flower buds. When the plants reached15 to 20 cm tall, they were inoculated with a suspension containing 10,000 nematode eggs. Four months after inoculation, the soils were removed from the plants for individual evaluation of the number of galls, number of eggs and reproduction factor (RF). Genotyping was performed with two and 13 microsatellite loci in hybrids and Psidium accessions, respectively. Total DNA was extracted by the CTAB 2x method and PCR products were analyzed by denaturing polyacrylamide gel 6%, stained with silver nitrate. Interspecific hybrids between GUA 161 PE P guajava x ARA 138 RR P. guineensewere highly tolerant to nematodes, with growth similar to the guava, and demonstrated high compatibility when grafted with the cultivar 'Paluma'. The 61 accessionsPsidiumaccessions showed similarity coefficient ranging from 0.75 to 1.00 and the dendrogram presented co-phenetic value of 0.85. Genetic variability was considered high ?ST=0.238 and it was observed formation of five groups at a cutoff of 83% similarity. The genetic similarity among P.guineense and some guava accessions were above 80%, suggesting greater possibility to obtain interespecific hybrids among these two species. / Os objetivos deste trabalho foram obter e avaliar h?bridos interespec?ficos do g?nero Psidium para resist?ncia ao M. enterolobii e analisar a variabilidade gen?tica de acessos de goiabeiras e ara?azeiros do banco ativo de germoplasma da Embrapa Semi?rido, com base em microssat?lites, para fornecer subs?dios para programas de recursos gen?ticos e de melhoramento com ?nfase para cruzamentos de goiabeira com outras esp?cies do g?nero Psidium.Os cruzamentos foram realizados quando os bot?es florais apresentavam ruptura do c?lice.Quando as plantas atingiram 15 a 20 cm de altura, foi realizada a inocula??o com suspens?o contendo 10.000 ovos do nematoide. Quatro meses ap?s a inocula??o, foi removido o solo das plantas para avalia??o individual para n?mero de galhas, n?mero de ovos e fator de reprodu??o (FR). A genotipagem foi feita com dois e 13 locos de microssat?lites, nos h?bridos e nos acessos de Psidium. O DNA total foi extra?do pelo m?todo CTAB 2x e os produtos de PCR foram analisados em gel de poliacrilamida desnaturante 6% e corados com nitrato de prata. H?bridos interespec?ficos entre GUA 161 PE de P. guajava x ARA 138 RR de P. guineense foram altamente resistentes ao nematoide, apresentando crescimento similar ao da goiabeira, e demonstrado alta compatibilidade quando enxertada com a cultivar ?Paluma?.Os 61 acessos de Psidium apresentaram coeficiente de similaridade variando de 0,75 a 1,00. O dendrograma apresentou valor co-fen?tico de 0,85. A variabilidade gen?tica foi considerada alta 0,238(?ST)e observou-se forma??o de cinco grupos no ponto de corte de 83% de similaridade.A similaridade gen?tica entre P. guineense e alguns acessos de goiabeira foi superior a 80%, indicando maior possibilidade de sucesso em cruzamentos interespec?ficos entre essas duas esp?cies.
115

Análisis de los factores que determinan la resistencia al encamado y características de grano en arroz (Oryza sativa L.), y su asociación con otros caracteres, en varias poblaciones y ambientes: bases genéticas y QTLs implicados

Torró Torró, Isabel 01 February 2011 (has links)
Los objetivos de esta tesis son estudiar el comportamiento y el control genético de diferentes caracteres relacionados con la resistencia al encamado del arroz, así como parámetros de calidad del grano, en dos poblaciones que comparten el mismo parental femenino, y en dos condiciones de cultivo: las balsetas en que generalmente se realiza la selección de las primeras generaciones segregantes, y parcelas de campo; y analizar si es posible aumentar la eficiencia en la selección de estos caracteres: idoneidad de la selección en F2 e identificación de las regiones cromosómicas más importantes en la determinación de estos caracteres, y que puedan ser apropiadas para un programa de selección asistida por marcadores (M.A.S.). Para ello se ha realizado un análisis cuantitativo (estimas de heredabilidad, correlación entre caracteres y eficacia de selección), y un análisis de QTLs (loci que controlan los caracteres cuantitativos). En el genotipado de las poblaciones se han utilizado marcadores de tipo SSR. Se han identificado y caracterizado los loci implicados en el control genético de cada uno de los caracteres, y se han comparado su estabilidad y efectos en los diversos genotipos y ambientes. En muchos casos, se detectaron QTLs que afectan simultáneamente a varios caracteres, en coincidencia con las correlaciones encontradas entre los mismos caracteres. Se han localizado zonas de especial interés que podrían ser utilizadas para M.A.S. (selección asistida por marcadores). La selección fue efectiva para reducir la altura y aumentar el grosor y la longitud de los entrenudos basales en las dos poblaciones, y para incrementar del número de panículas y la resistencia al doblado en una de las poblaciones. / Torró Torró, I. (2010). Análisis de los factores que determinan la resistencia al encamado y características de grano en arroz (Oryza sativa L.), y su asociación con otros caracteres, en varias poblaciones y ambientes: bases genéticas y QTLs implicados [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/9317 / Palancia
116

Nuevas herramientas en la lucha contra las virosis del pimiento

Ibiza Gimeno, Vicente Pascual 19 September 2011 (has links)
Las enfermedades de etiología viral destacan por ser el principal factor limitante de las hortalizas. La estrategia más eficaz para el control consiste en la identificación de genes de resistencia y el posterior desarrollo de variedades resistentes. El principal objetivo de esta tesis se centra en el aprovechamiento y la caracterización de la variabilidad genética de las especies cultivadas del género Capsicum (C. annuum, C. chinense, C. frutescens, C. baccatum y C. pubescens). Se ha puesto a punto una plataforma de EcoTILLING que permite un cribado eficiente de la colección de entradas de Capsicum del Banco de Germoplasma del COMAV. Esta plataforma se exploró para la búsqueda de variantes alélicas de los genes eIF4E y eIF(iso)4E, implicados en la resistencia a virosis. Una colección de 31 entradas que representan distintas combinaciones de los alelos eIF4E y eIF(iso)4E se inocularon mecánicamente con el Potato virus Y (PVY) y el Tobacco etch virus (TEV). Cinco nuevas variantes del gen eIF4E (pvr210, pvr211, pvr212, pvr213, pvr214) están relacionadas con la respuesta de resistencia al PVY y al TEV. Diez microsatélites y cuatro combinaciones de AFLPs se utilizaron para caracterizar 260 entradas del género Capsicum. Se detectó la existencia de cierta estructuración intraespecífica relacionada geográficamente. C. baccatum y C. pubescens muestran un par de grupos genéticos, por un lado están las entradas procedentes de Bolivia y por el otro las entradas de Ecuador y Perú. Además, las entradas de C. chinense procedentes de Perú pudieron ser diferenciadas del resto. En este estudio las entradas de Ecuador y Perú han mostrado una diversidad elevada y similar a las de Bolivia, el cual es un importante centro de diversidad del género Capsicum. Por tanto, las entradas procedentes de estos países podrán constituir fuentes importantes de variación para ser utilizadas en los programas de mejora del pimiento. / Ibiza Gimeno, VP. (2011). Nuevas herramientas en la lucha contra las virosis del pimiento [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11549 / Palancia
117

Zařízení pro vzdálený WakeOnLan / Remote WakeOnLan

Pitner, Ivo January 2011 (has links)
This work deals with construction of an embedded system with remote access, whitch controls computers in the same network in order to reduce their energy consumption. For this purpose is used the WakeOnLAN technique. The device also uses two power components called SSR and  these are used for switching AC power to them attached appliances. The work discusses the TCP/IP architecture, system design and finally the firmware implementation.
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Diversidade genética de Drosophila prosaltans e D. austrosaltans (Diptera, Drosophilidae) de regiões de Mata Atlântica avaliada por marcadores microssatélites /

Paixão, Jéssica Fernanda January 2020 (has links)
Orientador: Lilian Madi-Ravazzi / Resumo: Drosophila prosaltans e Drosophila austrosaltans, do grupo saltans de Drosophila, são espécies neotropicais com distribuição em áreas florestais da América Central e do Sul e que podem ser encontradas em simpatria. A literatura sobre o grupo saltans de Drosophila é escassa e muitos trabalhos não são tão recentes. Assim, poucas são as informações disponíveis sobre os aspectos biológicos de ambas as espécies. Para D. prosaltans, existem trabalhos de isolamento reprodutivo, estrutura e polimorfismo cromossômico que apontam uma diferenciação de suas populações, entretanto, as informações em relação à diferenciação populacional de D. austrosaltans são praticamente inexistentes. Tal fato nos motivou a investigar os padrões de diversidade genética populacional dessas espécies provenientes de diferentes fitofisionomias de Mata Atlântica utilizando os microssatélites como marcador molecular. Foram desenvolvidos oligonucleotídeos de microssatélites específicos para D. prosaltans, cuja transferibilidade testada para D. austrosaltans mostrou resultados positivos. Identificamos na análise de 12 locos para D. prosaltans, uma alta heterozigosidade média (Ho = 0.45 ± 0.03) e uma diferenciação genética populacional moderada (Fst = 0.17 ± 0.02). Foi observada a formação de dois agrupamentos genéticos distintos nas populações de D. prosaltans, que não se correlacionam com a distribuição regional ou de fitofisionomia das populações, podendo esse padrão ser decorrente de características ecológica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Drosophila prosaltans and Drosophila austrosaltans, from the Drosophila saltans group, are neotropical species with distribution in forest areas of Central and South America and that can be sympatric. The literature on the Drosophila saltans group is scarce and many works are not so recent. Thus, little information is available on the biological aspects of both species. For D. prosaltans, there are works of reproductive isolation, structure and chromosomal polymorphism that point to a differentiation of its populations, however, the information regarding the population differentiation of D. austrosaltans is practically nonexistent. This fact motivated us to investigate the patterns of population genetic diversity of these species from different Atlantic Forest phytophysiognomies using microsatellites as a molecular marker. Microsatellite oligonucleotides specific for D. prosaltans were developed, whose transferability tested for D. austrosaltans showed positive results. In the analysis of 12 loci for D. prosaltans, we identified a high mean heterozygosity (Ho = 0.45 ± 0.03) and a moderate population genetic differentiation (Fst = 0.17 ± 0.02). The formation of two distinct genetic groups was observed in D. prosaltans populations, which do not correlate with the regional or phytophysiognomic distribution of the populations, and this pattern may be due to ecological characteristics, shared ancestral polymorphism, recurrent mutation and genetic drift (founder effect). The succes... (Complete abstract click electronic access below) / Mestre
119

Využití molekulárních markerů ve šlechtění mrkve

Sejbalová, Darina January 2018 (has links)
The aim tis work was study of diversity in carrot (Daucus carota), the analysis of the homogeneity of the parent material, the evaluation of the success of the crossing, and the resolution of the sterile and fertile genotypes of the samples used in crossing. Four hybrid carrot varieties and 12 lines were analyzed, four of which were sterile (CMS), with ten SSR markers and six CMS markers. Based on the calculated statistical values of DI, PI and PIC, the markers were highly variable. A total of 45 alleles were detected, with a mean of 4.5 alleles per locus and 4 zero alleles. The size of the allele ranged between 180 and 380 bp. The success rate of the crossing was evaluated, when the crossing of the Koloseum variety was evaluated as the most successful. Four SSR markers have been recommended as suitable for further study of the diversity and success rate of carrot crosses, namely GSSR-6, GSSR-16, GSSR-91 and GSSR-9. CMS markers successfully identified the sterile and fertile lines at one crossing (variety Koloseum) by Atp8 marker.
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URBAN DRAINAGE NETWORK REHABILITATION CONSIDERING STORM TANK INSTALLATION AND PIPE SUBSTITUTION

Ngamalieu Nengoue, Ulrich Aurèle 28 October 2019 (has links)
[ES] La rehabilitación de las redes de drenaje es uno de los procesos fundamentales que los administradores y responsables de la gestión de redes de drenaje deben implementar para adaptar las redes defectuosas a los efectos adversos del cambio climático y la urbanización. Las soluciones tradicionales pasan por la sustitución de tuberías o la instalación de tanques de tormenta (TT). En esta tesis, el escenario propuesto combina la sustitución de tuberías y la instalación de TT para la rehabilitación de redes de drenaje. Los resultados de varias simulaciones en varias redes mostraron que el uso combinado de la sustitución de tuberías y la instalación de TT en la rehabilitación de redes de drenaje proporciona mejores resultados que la separación de los dos escenarios de rehabilitación. Tal metodología de rehabilitación necesita un tiempo de computación elevado para proporcionar soluciones aceptables que a menudo se encuentran atrapados en mínimos locales. El objetivo de esta tesis es proponer una metodología que permita obtener mejores resultados durante la rehabilitación de redes de drenaje considerando el uso combinado de la sustitución de tuberías y la instalación de TT. La metodología debe considerar la reducción del espacio de búsqueda (SSR). Cuatro opciones claves están combinadas para lograr reducir el espacio de búsqueda del problema. Estas opciones son: Reducir la cantidad de nudos en los que podrían instalarse los TT. Reducir el número de líneas en las que podría haber un cambio en el diámetro Reducir la discretización que se hace de la sección de cada uno de los TT. Reducir el número de diámetros candidatos en las tuberías. Una vez que se reduce el espacio de búsqueda, el algoritmo pseudo genético (APG) utilizado en esta tesis para la optimización mono-objetivo puede explorar más partes del espacio de búsqueda en menos tiempo. Lo que resulta es la obtención de mejores resultados. Por la optimización multiobjetivo, el NSGA-II utilizado puede proporcionar frentes de Pareto rápidamente para los diferentes escenarios considerados después del proceso de optimización. El objetivo general se dividió en objetivos específicos que se detallan a continuación: El primer objetivo específico consiste en formular un problema de optimización que verifique que la rehabilitación teniendo en cuenta la instalación de los TT y la sustitución de las tuberías proporciona mejores resultados que cualquiera de las dos estrategias implementadas por separado. Evaluar adecuadamente las funciones de costes utilizadas para formar las funciones objetivo constituye el segundo objetivo específico. Los diferentes costes considerados son: costes de sustitución de tuberías, costes de instalación de TT y costes de daños por inundación. El tercer objetivo específico es desarrollar un modelo de rehabilitación considerando la instalación de TT y la sustitución de tuberías, basado en APG y el Modelo SWMM. Los costes de inversiones y los costes de daños por inundaciones no se pueden sumar debido a sus tipos. Los costes de inversiones son reales mientras que los costes de daños por inundaciones son futuribles, dependen de la probabilidad de ocurrencia de la lluvia. Por lo tanto, el cuarto objetivo específico de esta tesis es proponer un algoritmo multiobjetivo evolucionario para la rehabilitación de redes de drenaje considerando la instalación de TT y la sustitución de tuberías. Para la optimización de un mono objetivo y multiobjetivo, el tiempo de cálculo es elevado. También las soluciones objetivas estaban atrapadas en mínimos locales. El quinto objetivo es proponer una metodología de reducción del espacio de búsqueda (SSR) para resolver este problema. El sexto objetivo específico consiste en llevar a cabo un análisis de sensibilidad para verificar los efectos del SSR en el resultado final del proceso de optimización. Por lo tanto, se seleccionaron diferentes tamaños de poblac / [CAT] La rehabilitació de les xarxes de drenatge és un dels gestors de processos fonamentals i la necessitat responsable d'implementar per adaptar les xarxes defectuoses als efectes adversos del canvi climàtic i la urbanització. A la literatura, la installació de canonades o substitució de canonades són els dos escenaris presentats pels autors. En aquesta tesi, un tercer escenari proposa combinar la installació de canonades de substitució i tancs de tempesta (TT) per a la rehabilitació de xarxes de drenatge. Els resultats de diverses simulacions a diverses xarxes van mostrar que la combinació d'ús de canvis de substitució de canonades i TT a la rehabilitació de xarxes de drenatge proporciona millors resultats que la separació dels dos escenaris de rehabilitació. Desafortunadament, aquesta metodologia de rehabilitació requereix temps de càlcul elevat per proporcionar solucions acceptables que sovint es troben en mínim local. L'objectiu d'aquesta tesi és proposar una metodologia que permeti reduir el temps de càlcul i obtenir millors resultats durant la rehabilitació de la xarxa de drenatge considerant l'ús combinat de la instal·lació dels TT de substitució de canonades. L'estratègia adoptada combina, en una metodologia estructurada, quatre opcions clau per reduir l'espai de cerca del problema: Reduir el nombre de nodes en què podrien instal·lar-se els TT. Reduir el nombre de línies en què podria haver-hi un canvi de diàmetre Reduir la discretització que es fa de la secció de cadascun dels TT. Reduir la quantitat de diàmetres candidats à les canonades. Un cop reduït l'espai de cerca, l'algorisme pseudo-genètic (PGA) que s'utilitza en aquesta tesi per a l'optimització d'un únic objectiu (SO) pot explorar fàcilment l'espai de cerca en menys temps, resultant en obtenir millors resultats. Per a l'optimització del MO, la NSGA-II pot proporcionar fronts de Pareto ràpidament per als diferents escenaris considerats després del procés d'optimització. L'objectiu general es va a dividir en objectius específics detallats a continuació: El primer objectiu específic consisteix a formular un problema d'optimització que verifiqui que la rehabilitació considerant la instal·lació de TT i la seva substitució proporciona millors resultats que qualsevol de les dues estratègies implementades per separat. Valorar adequadament les funcions de cost que s'utilitzen per formar les funcions objectives, i constitueix el segon objectiu específic. Els diferents costes considerats són: Costes d'inversions i costes de danys a les inundacions. El tercer objectiu específic és desenvolupar un model de rehabilitació considerant la instal·lació de TT i la substitució de canonades, basant-se en el PGA i el model SWMM. Els costos d'inversions i els costos de danys per inundacions no es poden sumar a causa d'un tipus. Els costes d'inversions són reals mentre els costes d'anuncis per a les futures fonts del futur són dependents de la probabilitat d'obertura de la pluja. Per tant, el cos objectiu específic d'aquesta tesi és propiciar un algorisme multiobjetiu evolutiu per a la rehabilitació de la xarxa de navegació considerant la instal·lació de TT i la substitució de tuberies. Per a l'optimització d'un únic objectiu i multi-objectiu, el temps de càlcul s'eleva. També es va sospitar que les solucions objectives eren atrapades en els mínims locals. El cinquè objectiu és proposar una metodologia de la reducció de l'espai de cerca (SSR) per resoldre aquest problema El sisè objectiu específic consisteix a realitzar una anàlisi de sensibilitat per verificar els efectes de SSR sobre el resultat final del procés d'optimització. Per tant, es van seleccionar diferents grandàries de població i valors de criteris de parada i es van realitzar simulacions per a diferents configuracions. El setè objectiu específic d'aquesta tesi és proposar una nova metodologia de rehabilitació considerant la tècnica / [EN] Drainage networks rehabilitation is one of the fundamental process that managers and responsible need to implement to adapt defective networks to climate change and urbanization adverse effects. In the literature, pipes substitution or storm tanks (STs) installation are the two scenarios presented by authors. In this thesis, a third scenario proposed combine pipes substitution and STs installation for drainage networks rehabilitation. Results of several simulations on various networks showed that the combine use of pipes substitution and STs installation in drainage networks rehabilitation provides better results than separation of the two rehabilitation scenarios. Unfortunately, such rehabilitation methodologies are computationally time consumers. They need much time to provide acceptable solutions which are often caught up in local minima. The aim of this thesis is to propose a drainage networks rehabilitation methodology based on the combine use of pipes substitution and STs installation. The methodology considers search space reduction (SSR) technique. The adopted strategy combines in a structured methodology four key options aiming at reducing the search space (SS) of the problem: Reduce the number of nodes in which STs could potentially be installed. Reduce the number of lines in which there could potentially be a change in diameter Reduce the discretization that is made of the section of each of the STs. Reduce the number of candidate diameters in the pipes. Once the search space is reduced, the pseudo genetic algorithm (PGA) used in this thesis for single objective (SO) optimization can easily explore the search space in less time resulting in the obtention of better results. For the MO optimization, the NSGA-II can provide rapidly Pareto fronts for the different considered scenarios after the optimization process. The general objective was divided in specific objectives detailed as follow: The first specific objective consists of formulate an optimization problem that verifies that rehabilitation considering STs installation and pipes substitution provides better results than any of the two strategies implemented separately. Adequately assess the cost functions used to form the objective functions constitutes the second specific objective. The different costs considered are: Investments costs and flood damage costs. The third specific objective is to develop a rehabilitation model considering STs installation and pipes substitution, based on PGA and the Storm Water management Model. Investment costs and flood damage costs could not be summed due to their types. Investment costs are reals while, flood damage costs depend on the rainfall probability. So, the fourth specific objective of this thesis is to propose a MOEA for drainage networks rehabilitation considering STs installation and pipes substitution. For SO and Multi-objective (MO) optimization, the computation time is elevated. It was also suspected that the objective solutions were caught up in local minima. The fifth objective is to propose an SSR methodology to solve this issue The sixth specific objective consist of carry out a sensitivity analysis to verify the effects of the SSR on the final result of the optimization process. So, different population sizes and stop criteria values were selected and simulation for different configurations were performed. The seventh specific objective of this thesis is to propose a new rehabilitation methodology considering SSR technique for MO optimization. For each specific objective presented in this thesis, an application to a drainage network has been made and the obtained results were satisfactory. A simple network was used to apply the simple optimization methodology based on PGA algorithm A medium size network was used to apply the SO optimization, the MO optimization and the SSR methodology. Finally, a large and mesh network was used to apply the MO optimization methodology considering SSR. / Ngamalieu Nengoue, UA. (2019). URBAN DRAINAGE NETWORK REHABILITATION CONSIDERING STORM TANK INSTALLATION AND PIPE SUBSTITUTION [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/129869 / TESIS

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