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Associação genômica para resistência de soja à pústula-bacteriana / Genome-wide association study of resistance to bacterial-pustule in soybeanBarbosa, Rosângela Maria 29 August 2017 (has links)
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Previous issue date: 2017-08-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A pústula-bacteriana em soja é causada pela bactéria Xanthomonas axonopodis pv. glycines. Esta doença teve aumento expressivo em sua agressividade nos cultivares de soja nas últimas safras. O principal método de controle da pústula-bacteriana é o uso de cultivares resistentes. A identificação de fontes de resistência à pústula-bacteriana é um desafio para os melhoristas, uma vez que existem várias estirpes da fitobactéria e interação genótipos x estirpes para a resistência ao patógeno. O que pode ser resolvido com o auxílio de marcadores moleculares SNPs via análise de associação genômica ampla. Diante disso, objetivou-se caracterizar fenotipicamente 118 genótipos de soja quanto à resistência a X. axonopodis pv. glycines; identificar marcadores moleculares do tipo SNPs ligados a genes responsáveis pela resistência à pústula-bacteriana e identificar cultivares de soja portadores de alelos de resistência à pústula bacteriana. Foram inoculados 118 genótipos de soja com os isolados XAG2440 p e XAG2447. O delineamento experimental foi o inteiramente casualizados, com sete repetições. A parcela experimental foi um pote plástico de 200 ml de volume com uma planta. A severidade da doença foi avaliada 15 dias após a inoculação com uma escala de notas de severidade de pústula bacteriana de 1 a 5, em que 1= a ausência de pústulas e 5= maior severidade de pústula bacteriana. O agrupamento das médias de severidade da doença dos genótipos pelo teste de Skott-Knott permitiu a formação de cinco grupos de genótipos quando se usou a estirpe XAG2440 p e três grupos com a estirpe XAG2447.O genótipo CD244RR foi resistente a ambas as estirpes. Já o genótipo TMG 7161RR foi o primeiro a apresentar sintomas de pústula bacteriana, mostrando-se altamente suscetível à ação de ambas as estirpes. Foram identificados onze potenciais marcadores SNPs em cinco cromossomos associados com a resistência à pústula-bacteriana causada pela estirpe XAG2440 p . O marcador Gm03_46214163_C_T é o mais fortemente associado com a resistência à pústula-bacteriana causada pela estirpe XAG2440 p e está localizado no cromossomo 3. Para a estirpe XAG2447 foram identificados cinco potenciais marcadores SNPs em três cromossomos. O marcador Gm17_7280661_C_T localizado no cromossomo 17 é o marcador mais fortemente associado à resistência à pústula- bacteriana causada pela estirpe XAG2447. Com base nos marcadores recomendamos fvcruzamentos envolvendo as cultivares CD244RR, CD243RR, CD5969, FUNDACEP55RR e FUNDACEP58RR para obter genótipos portadores de todos os alelos de resistência à estirpe XAG2440 p . Esses marcadores, depois de validados, poderão ser utilizados para seleção assistida por marcadores, de forma a aumentar a frequência de alelos de resistência à ação das estirpes XAG2440 p e XAG2447. / Bacterial pustule in soybean is caused by the bacterium Xanthomonas axonopodis pv. glycines. This disease had an expressive increase in its aggressiveness in soybean cultivars in the last harvests. The main method control of bacterial pustule is the use of resistant cultivars. The identification of sources of resistance to bacterial pustule is a challenge for breeders as there are several strains of this phytobacteria and interaction genotypes x strains for resistance to the pathogen. What can be solved with the identification of molecular markers SNPs with Genome-wide association studies. On this, the objective of this study was to characterize phenotypically 118 soybean genotypes for resistance to X. axonopodis pv. glycines; to identify molecular markers of the SNPs type linked to genes responsible for resistance to bacterial pustule and to identify soybean cultivars carrying resistance alleles to bacterial pustule. 118 soybean genotypes were inoculated with the isolates XAG2440p and XAG2447. The experimental design was the completely randomized with seven replications. The experimental plot was a plastic pot of 200 ml volume with a plant per pot. After 15 days of inoculation plants were examined for lesions characteristic of bacterial pustule with a scale of bacterial pustule severity scores from 1 to 5, where 1 = absence of pustules and 5 = greater severity of bacterial pustule. The clustering of disease severity averages of the genotypes by the Skott-Knott test allowed the formation of five genotype groups when using the strain XAG2440p and three groups with the strain XAG2447. The genotype CD244RR was resistant to both strains. The genotype TMG 7161RR was the first to present symptoms of bacterial pustule, being highly susceptible to the action of both strains. Eleven potential SNPs markers were identified on five chromosomes associated with resistance to bacterial pustule caused by strain XAG2440p. The marker Gm03_46214163_C_T is most strongly associated with resistance to bacterial pustule caused by strain XAG2440p and is located on chromosome 3. For the strain XAG2447 were identified five potential SNPs markers on three chromosomes. The marker Gm17_7280661_C_T located on chromosome 17 is the marker most strongly associated with resistance to bacterial pustule caused by strain XAG2447. Based on the markers we recommend crosses involving the cultivars CD244RR, CD243RR, CD5969, FUNDACEP55RR and FUNDACEP58RR to obtain genotypes carrying all the strain resistance alleles XAG2440p. These markers, once validated, may be used for marker- assisted selection in order to increase the frequency of resistance alleles to strains XAG2440p and XAG2447.
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Metabolômica de plantas transgênicas de soja (Glycine max L. Merril) expressando BiP em resposta a inoculação com Pseudomonas syringae pv. tomato / Metabolomic analysis of transgenic soybean leaves (Glycine max L. Merril) expressing BiP in response to inoculation with Pseudomonas syringae pv. tomatoRodrigues, Juliano Mendonça 24 July 2017 (has links)
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Previous issue date: 2017-07-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Brasil é o segundo produtor mundial de soja. Porém, estresses bióticos e abióticos tem limitado a expansão da produtividade. Nosso grupo de pesquisa do LBMP, BIOAGRO-UFV, tem observado que plantas transgênicas superexpressando BiP (Binding protein), chaperona com atividade associada à via UPR (unfolded protein response) e à modulação de eventos de PCD (programmed cell death), são mais tolerantes à seca pela manutenção da homeostase celular e retardo do acionamento da PCD. Dos fitopatógenos, a Pseudomonas syringae pv. tomato provoca reação de hipersensibilidade na soja, uma vez que a interação planta-bactéria é incompatível. Neste trabalho, foi caracterizado o perfil metabólico dos genótipos transgênico superexpressando BiP (C9) e selvagem (WT) por GC-MS. Foram também avaliados por LC-MS, a abundância de fito-hormônios e alguns metabólitos secundários alvos em resposta à interação de soja com P. s. pv. tomato para determinar alterações metabólicas nestes genótipos relacionadas com o fenótipo de morte celular e reações de hipersensibilidade. O acúmulo de aminoácidos, açúcares e ácidos orgânicos pode estar relacionado ao controle de danos ocasionado pelo estresse biótico, sendo menor em C9 devido à capacidade de BiP em manter a homeostase celular. Compostos como di- hidroesfingosina (DHS) e gama-aminobutirato (GABA) podem estar envolvidos com mecanismos de PCD em células visando restringir a colonização do tecido foliar por bactérias. Além disso, observou-se uma tendência para o aumento de ácido salicílico (SA) e ácido jasmônico (JA), embora os níveis de ácido abscísico (ABA) em C9 tenham sido menores, indicando o papel antagonista do ABA na via de sinalização mediada por SA/JA e síntese de fitoalexinas ao longo da infecção bacteriana. A considerável importância do SA e JA, que disparam vias de sinalização de controle microbiano, em C9 possivelmente está no controle negativo da PCD por BiP, que impede a contenção do patógeno por esta via. As concentrações de metabólitos secundários, por sua vez, sofreram o maior incremento ao longo do tempo, sobretudo daidzeína e genisteína, sendo maior em C9. Este acréscimo pode estar associado com as propriedades antimicrobianas das isoflavonas. Por isso, em plantas C9, a superexpressão de BiP atrasa a via de PCD, impedindo a contenção da colonização bacteriana em tempo hábil, sendo a ação antimicrobiana o mecanismo de resposta predominante em C9, ao passo que em WT predomina a via de PCD. / Brazil is the world's second largest soybean's producer. However, biotic and abiotic stresses have limited productivity expansion. Our research group at the LBMP, BIOAGRO-UFV, has observed that transgenic plants overexpressing BiP (Binding protein), chaperone with activity associated with pathway UPR (unfolded protein response) and modulation of PCD (programmed cell death) events, are more tolerant to drought by the maintenance of cellular homeostasis and retarding the activation of PCD. Plant pathogens, Pseudomonas syringae pv. tomato provokes hypersensitivity reaction in soybean, since it is an incompatible interaction. In this work, the metabolic profile of the transgenic genotypes overexpressing BiP (C9) and wild type (WT) by GC-MS. We also evaluated by LC-MS, the abundance of phytohormones and some target secondary metabolites in response to the interaction of soybean with P. s. pv. tomato to determine metabolic changes in these genotypes related to cell death phenotype and hypersensitivity reactions. The accumulation of amino acids, sugars and organic acids may be related to damage control caused by biotic stress, being lower in C9 due to BiP's ability to maintain cellular homeostasis. Compounds such as dihydrosphingosine (DHS) and gamma aminobutyric acid (GABA) may be involved with PCD mechanisms in cells with the aim of to restrain the colonization of foliar tissue by bacteria. Furthermore, there was a tendency for increased salicylic acid (SA) and jasmonic acid (JA), although abscisic acid (ABA) levels have been lower in C9 plants, indicating the ABA antagonist role in the SA-mediated or JA-mediated signaling pathway and phytoalexin synthesis throughout the bacterial infection. The considerable importance of SA and JA, which trigger pathways of microbial control signaling, in C9 is possibly in the negative PCD control by BiP, which prevents the containment of the pathogen for this pathway. Concentrations of secondary metabolites suffered the greatest increase over time, especially daidzein and genistein, being higher in C9 plants. This increase may be associated with the antimicrobial properties of isoflavones. Therefore, in C9 plants, the overexpression of BiP delays the PCD pathway, preventing bacterial colonization in a timely manner, and the antimicrobial action is the predominant response mechanism in C9, whereas in WT, the PCD pathway predominates.
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Caracterização bioquimica de aminopeptidases de Xylella fastidiosa e Xanthomonas axonopodis pathovar citri / Biochemical characterization of aminopeptidases from Xylella fastidiosa and Xanthomonas axonopodis pv citriSantos, Kelly 15 December 2006 (has links)
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Previous issue date: 2006 / Resumo: Aminopeptidases realizam a clivagem de resíduos de aminoácidos de peptídios e proteínas. Elas estão presentes em todos os organismos e desempenham importantes papéis em processamento de alimentos, maturação de proteínas pela eliminação do resíduo de metionina Nterminal, patogenicidade e muitos outros processos celulares. Neste trabalho foi realizada a clonagem, expressão, purificação e caracterização de uma prolina iminopeptidase de Xylella fastidiosa(Xf1510) e de uma aminopeptidase de Xanthomonasaxonopodispv. citri (Xac2987). Estes dois genes foram anotados como prováveis prolina iminopeptidases. Ambos foram clonados em vetor de expressão pET15b, expressados em Escherichiacoli, e purificados na fração solúvel em um passo por cromatografia a metal imobilizado (IMAC). Ensaios de atividade enzimática confirmaram que a Xf1510 é uma prolina iminopeptidase, e que a Xac2987 é uma aminopeptidase de amplo espectro e não uma prolina iminopeptidase como foi anotada no banco de dados, sendo capaz de catalisar a remoção de diferentes aminoácidos de substratos sintéticos. Os espectros de dicroísmo circular das enzimas mostram que ambas podem ser incluídas na família das a/ß a/ß hidrolases e que estão enoveladas. A proteína Xf1510 apresenta maior atividade na faixa de pH entre 7,5 e 8,5. A temperatura ótima para hidrólise de prolina foi 45ºC. O pH ótimo para a atividade enzimática da proteína Xac2987 foi encontrado na faixa de pH de 6,5 e 7,5; sendo o pH ótimo 6,6. Neste pH a temperatura ótima para a hidrólise de alanina foi encontrada à 40ºC. Estudos estruturais com relação ao pH e estabilidade térmica das proteínas foram acompanhados por dicroísmo circular. Estudos de desnaturação térmica e química indicam que as proteínas Xf1510 e Xac2987 apresentam estados intermediários antes de atingirem o desenovelamento máximo / Abstract: Aminopeptidases release the Nterminal amino acid residue from polypeptides and proteins. They are present in all organisms and play several important roles in food processing, maturation of proteins by elimination of the Nterminal methionine, pathogenicity and many other cellular processes. We report here, the cloning, expression, purification and characterization of a proline iminopeptidase from X.fastidiosa(Xf1510) and a broad specificity aminopeptidase from X.axonopodispv. citri(Xac2987). These two genes have been annotated as putative proline iminopeptidase. Both genes were cloned into the pET15b expression vector, expressed in Escherichia coli, and purified to apparent homogeneity in one step by IMAC. The protein was expressed in the soluble fraction and could be purified in one step by IMAC. Enzymatic assays confirmed Xf1510 as a PIP, and Xac2987 as a broad spectrum aminopeptidase, being able to catalyze the removal of different synthetic substrates. The circular dichroism spectrum allowed us to classify the proteins as part of the a/ß hydrolyses family. Structural studies with pH dependence and thermal stability were preformatted by circular dichroism. The Xf1510 protein presents greater activity in the range of pH between 7,5 and 8,5. The optimum temperature for prolina hydrolysis was 45ºC. The pH optimum for the enzymatic activity of the Xac2987 protein was found in the range of pH of 6,5 and 7,5; being pH optimum 6,6. In this pH the temperature for alanine hydrolysis was found to 40ºC. Structural studies with regard to pH and thermal stability of proteins had been followed by circular dichroism. Studies of thermal and chemical denaturation indicate that the proteins Xf1510 and Xac2987 present intermediate states before reaching the maximum unfolding / Doutorado / Bioquimica / Doutor em Biologia Funcional e Molecular
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Produção de goma xantana a partir de soro de leite por Xanthomonas campestris pv. campestris LFR- 4Oliveira, Sara Horacio de January 2005 (has links)
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Previous issue date: 2005 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A goma xantana é sem dúvida um dos mais importantes biopolímeros comerciais
obtidos por fermentação através da bactéria Xanthomonas campestris pv.
campestris. O seu êxito no mercado deve-se, sem dúvida, às suas características
reológicas e de estabilidade, sendo empregada nas indústrias de alimentos,
petrolífera e petroquímica, agroquímica e farmacêutica. As fontes de carbono
preferenciais para a produção da xantana são a glicose, o amido e a sacarose.
Entretanto, alguns trabalhos de pesquisa sugerem fontes alternativas para a
produção da goma. O soro de leite, resultante da fabricação de queijos, vem sendo
estudado para a produção da xantana. O emprego de resíduos industriais em
bioprocessos permite a utilização de substratos de baixo custo, agregando valor
comercial e minimizando os graves problemas de impacto ambiental. Neste trabalho,
foram utilizadas sete linhagens da bactéria Xanthomonas campestris pv. campestris
com o objetivo de avaliar a produção da goma xantana tendo como substrato o soro
de leite suplementado com sais minerais. Para produção de goma foi selecionada a
linhagem da bactéria Xanthomonas campestris pv. campestris LFR-4. Com a
linhagem selecionada, foi avaliado os parâmetros capazes de influenciar o
rendimento do processo e os nutrientes essenciais ao meio de soro de leite. Os
experimentos foram conduzidos em fermentador BIOSTAT B (B. Braun Biotech
Internacional) com 2 L de capacidade útil contendo 1500mL de meio de produção. O
biorreator é do tipo tanque agitado, equipado com rotor de disco de seis pás,
controles de aeração, temperatura, pH e antiespumante. Com relação ao estudo
realizado para avaliar a potencialidade de produção de xantana, foram levados em
consideração os parâmetros fator de conversão de substrato em produto
Yp/s=0,62g/g μmax=0,030h, viscosidade final do mosto fermentado de 2.981,38 cP. A
linhagem LFR-4 exibiu capacidade viscosificante de 214.8 cP/g.L-1. O mosto
fermentado apresentou comportamento típico para fluido pseudoplastico. Os
resultados obtidos sugerem que a linhagem selecionada apresenta potencial para
produção de xantana tendo como substrato o soro de leite
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Design and optimization of cascaded DCG based holographic elements for spectrum-splitting PV systemsChrysler, Benjamin D., Ayala Pelaez, Silvana, Kostuk, Raymond K., Wu, Yuechen 17 October 2017 (has links)
In this work, the technique of designing and optimizing broadband volume transmission holograms using dichromate gelatin (DCG) is summarized for solar spectrum-splitting application. Spectrum splitting photovoltaic system uses a series of single bandgap PV cells that have different spectral conversion efficiency properties to more fully utilize the solar spectrum. In such a system, one or more high performance optical filters are usually required to split the solar spectrum and efficiently send them to the corresponding PV cells. An ideal spectral filter should have a rectangular shape with sharp transition wavelengths. DCG is a near ideal holographic material for solar applications as it can achieve high refractive index modulation, low absorption and scattering properties and long-term stability to solar exposure after sealing. In this research, a methodology of designing and modeling a transmission DCG hologram using coupled wave analysis for different PV bandgap combinations is described. To achieve a broad diffraction bandwidth and sharp cut-off wavelength, a cascaded structure of multiple thick holograms is described. A search algorithm is also developed to optimize both single and two-layer cascaded holographic spectrum splitters for the best bandgap combinations of two- and three-junction SSPV systems illuminated under the AM1.5 solar spectrum. The power conversion efficiencies of the optimized systems under the AM1.5 solar spectrum are then calculated using the detailed balance method, and shows an improvement compared with tandem structure.
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Reactive Power Control for Voltage ManagementHasan, MD. Shakib January 2017 (has links)
This thesis presents methods for voltage management in distribution systems with high photovoltaic (PV) power production. The high PV penetration leads to both new challenges such as voltage profile violation and reverse power flow, and also new opportunities. Traditionally, the voltage control in the distribution network is achieved by common devices in the networks such as capacitor banks, static synchronous compensators (STATCOMs) and on-load tap changers (OLTCs). This thesis has considered existing reactive power capable solar PV inverters together with STATCOMs to provide voltage support for the distribution network. In this thesis, two effective coordination methods using the STATCOM and PV inverters are developed in order to study their interaction and how they together can stabilize the voltage level. Data from existing low-voltage (LV) and medium-voltage (MV) networks are used for a case study. The first control method is developed for LV network’s voltage control by means of PV inverter and STATCOM. The second control method is developed for both LV and MV networks’ voltage control, where reactive power control in PV inverters and STATCOMs are used in the LV network and only STATCOMs in the MV network. The control methods follow a hierarchical structure where reactive power compensation using PV inverters are prioritized. The STATCOMs, first in the LV and thereafter in the MV network in the second control method, are used only when the PV inverters are not able to provide or consume enough reactive power. This is beneficial due to the significant reduction in numbers of STATCOMs and their operation. The simulation results indicate that the proposed method is able to control both the over- and undervoltage situations for the test distribution networks. It is also shown that reactive power supply at night by the PV inverters can be an important resource for effective voltage regulation by using the proposed coordinated voltage control method.
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Assessment of a Solar PV Re-Powering Project in Sweden Using Measured and Simulated DataKorde, Anukool January 2017 (has links)
Re-powering solar PV plants is an upcoming discussion on the global stage. Although the respective component warranties indicate the time to change the system machinery, the methodology and justification for carrying this out are two aspects that need further study. The rooftop solar PV system on top of Dalarna University was re-positioned in 2014. Prior to installing the system in its new position, the system arrays were reconfigured and new inverters were installed. This thesis aimed to compare and analyze two sections of the solar power plant to understand which amongst them performs better. Graphs depicting energy, current, voltage and other parameters were formulated to ascertain the efficacy of the array configurations for this Nordic latitude. Thereafter, PVsyst and SAM were used to compare the simulated results with the actual output from the system. It was found that the measured energy output from one section of the solar power plant was higher than that of the other during 2014. On an annual basis, this difference was 21.5 kWh or 2%. On closer inspection, this contrast was attributed to a difference in yield early in the morning. Further, PVsyst simulated the annual energy with a deviation of less than 1% than what was measured, whereas SAM measured a deviation in energy measurement of 2.5% higher than the actual measured energy. These values were obtained using the detailed design options for both softwares. A point to keep in mind is that prior experience of working with both these softwares is recommended prior to carrying out the simulations on these softwares. An underlying point to note in this study is its limitations. This study is valid in the northern latitudes, such as the Nordic climates, since other regions would not have such low (sub-zero) temperatures to account for while sizing the inverter. In regions of high irradiance, a system re-powered in a way such as the system in this case would have higher clipping losses. Relevant previous studies and related topics have been visited, summarized and cited.
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Dlx Gene Regulation of Zebrafish GABAergic Interneuron DevelopmentMa, Wenqian January 2011 (has links)
Abstract
The Dlx genes play an important role in the differentiation and migration of
gamma-aminobutyric acid (GABA) interneurons of mice. GABAergic interneurons
are born in the proliferative zones of the ventral telencephalon and migrate to the
cortex early during mouse development. Single Dlx mutant mice show only subtle
phenotypes. However, the migration of immature interneurons is blocked in the
ventral telencephalon of Dlx1/Dlx2 double mutant mice leading to reduction of
GABAergic interneurons in the cortex. Also, Dlx5/Dlx6 expression is almost entirely
absent in the forebrain, most probably due to cross-regulatory mechanisms.
In zebrafish, the role of dlx genes in GABAergic interneuron development is
unknown. By injecting Morpholino, we double knocked down dlx1 and dlx2 genes in
wildtype zebrafish to investigate the function of the two genes in zebrafish
GABAergic interneuron development. By comparing different subsets of GABAergic
interneuron development in wildtype and dlx1/2 morphant zebrafish forebrain, we
found out that at 3dpf, 4dpf and 7dpf, double knockdown of dlx1 and dlx2 genes in
zebrafish remarkably reduced the number of Calbindin-, Somatostatin- and
Parvalbumin-positive GABAergic neurons, whereas the development of
Calretinin-positive neurons is slightly affected. These results suggest that in zebrafish,
dlx1a and dlx2a genes are important for the development of certain subtypes of
GABAergic interneurons (Calbindin-, Somatostatin- and Parvalbumin-positive
neurons) and may have minor influence on Calretinin-positive neuron development.
This also suggests that different regulatory mechanisms are involved in the
development of the different subtypes of GABAergic interneurons.
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Design of Multi-junction Solar Cells on Silicon Substrates Using a Porous Silicon Compliant MembraneWilkins, Matthew M. January 2013 (has links)
A novel approach to the design of multi-junction solar cells on silicon substrates for 1-sun applications is described. Models for device simulation including porous silicon layers are presented. A silicon bottom subcell is formed by diffusion of dopants into a silicon wafer. The top of the wafer is porosified to create a compliant layer, and a III-V buffer layer is then grown epitaxially, followed by middle and top subcells. Due to the resistivity of the porous material, these designs are best suited to high efficiency 1-sun applications. Numerical simulations of a multi-junction solar cell incorporating a porous silicon compliant membrane indicate an efficiency of 30.7% under AM1.5G, 1-sun for low threading dislocation densities (TDD), decreasing to 23.7% for a TDD of 10^7 cm^-2.
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Regional institutions and organizational capabilities : an analysis of the solar PV industry in Jiangsu and Shandong Regions in ChinaWang, Yue January 2015 (has links)
Studying organizational capabilities from the perspective of national institutions has been widely adopted in high tech industries in developed countries, but scarcely in developing countries. This research applies this framework into China to study the solar PV industry, but at the regional level. The solar PV industry in China has strongly developed in the global market in recent years, having been the biggest solar PV producer since 2007. However, there are contrast regional differences in the solar PV industry development between Jiangsu and Shandong. The solar PV producers in Jiangsu have stronger organizational capabilities to perform well compared to those in Shandong. Thus this research adopts the framework to explore the influence of regional institutions (the role of regional government, financial systems, inter-firm relations and education and labor systems) in building organizational capabilities (R&D capabilities in technology, capabilities in finance, managerial coordination and human resources) in solar PV industry in Jiangsu and Shandong regions. Comparative case studies are adopted in my research and the research has investigated six solar PV companies and several associated organizations. It is concluded that different regional institutions have different influences (to promote or hinder) in building organizational capabilities in the solar PV industry. Compared to Shandong, the regional institutions in Jiangsu can help solar PV companies to build organizational capabilities. The research findings indicate the importance of regional institutions in China.
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