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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.
351

Tamanho de ensaio de uniformidade para estimação do tamanho de parcela em hortaliças / Uniformity assay size for estimating the optimum plot size in vegetable

Schwertner, Diogo Vanderlei 16 May 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this work were determine the optimum plot size and the uniformity assay size for estimating the optimum plot size in order to evaluate the fresh fitomass of lettuce plants and the mass of fruits of pepper, tomato, snap bean and zucchini. Production data were collected in uniformity assay with lettuce, pepper, tomato, snap bean and zucchini conducted at the Departamento de Fitotecnia da Universidade Federal de Santa Maria. Inside the planting row were planned different uniformity assay sizes. For each uniformity assay size planned were performed 3.000 resamples with replacement and were estimated for each sample the coefficient of spatial autocorrelation of the first order (p), the variance (s2), the mean (m) and the optimum plot size (Xo) by the method of maximum curvature of the coefficient of variation model (CMCV). Posteriorly, were also calculated the minimum values, percentile 2,5%, mean, percentile 97,5% and maximum values of statistics p, s2, m and Xo. For Xo statistic, even was calculated the amplitude of the confidence interval of 95%. Finally, were determined the uniformity assay size, starting from the smaller uniformity assay size planned (three basic units) and considering as uniformity assay size the number of basic units from which the amplitude of the confidence interval of 95% of optimum plot size was minor or equal to two basic experimental units. The uniformity assay size influences the estimation of the optimum plot size for evaluate the fresh fitomass of lettuce plants and the mass of pepper, tomato, snap bean and zucchini fruits. Uniformity assay with 27 basic units (27 plants) are enough for estimate the optimum plot size for evaluate the fresh fitomass of lettuce plants with a confidence interval of 95% minor or equal to two basic experimental units. Uniformity assay with pepper with 29 basic units (29 plants) in plastic greenhouse, with tomato with 12 basic units (12 plants) in plastic tunnel and with snap bean with 21 basic units (42 plants) in plastic tunnel, are enough for estimate the optimum plot size for evaluate the mass of fruits with a confidence interval of 95% minor or equal to two basic experimental units. Uniformity assay with snap bean with 18 basic units (36 plants) and with zucchini with ten basic units (ten plants) in plastic greenhouse are enough for estimate the optimum plot size for evaluate the mass of fruits with a confidence interval of 95% minor or equal to three basic experimental units. It is recommended the use of parcels with six basic experimental units for evaluate the fresh fitomass of lettuce plants and parcels with seven, five, six and eight basic experimental units, respectively, for evaluate the mass of fruits of pepper, tomato, snap bean and zucchini. / O objetivo deste trabalho foi determinar o tamanho de parcela e o tamanho de ensaio de uniformidade para estimar o tamanho de parcela a fim de avaliar a fitomassa fresca de plantas de alface e a massa de frutos de pimentão, de tomateiro, de feijão-vagem e de abobrinha italiana. Dados de produção de alface, de pimentão, de tomateiro, de feijão-vagem e de abobrinha italiana foram coletados em ensaios de uniformidade realizados no Departamento de Fitotecnia da Universidade Federal de Santa Maria. Dentro de cada linha de cultivo foram planejados diferentes tamanhos de ensaios de uniformidade. Para cada tamanho de ensaio de uniformidade planejado foram realizadas 3.000 reamostragens com reposição e estimados para cada amostra o coeficiente de autocorrelação espacial de primeira ordem (p), a variância (s2), a média (m) e o tamanho de parcela (Xo) pelo método da curvatura máxima do modelo do coeficiente de variação (CMCV). Posteriormente, também foram calculados os valores mínimo, percentil 2,5%, média, percentil 97,5% e máximo das estatísticas p, s2, m, e Xo. Ainda, para a estatística Xo, calculou-se a amplitude do intervalo de confiança de 95%. Finalmente, determinou-se o tamanho de ensaio de uniformidade, partindo-se do menor tamanho de ensaio planejado (três unidades básicas) e considerando como tamanho de ensaio de uniformidade o número de unidades básicas a partir do qual a amplitude do intervalo de confiança de 95% foi menor ou igual a duas unidades experimentais básicas. O tamanho do ensaio de uniformidade influencia a estimativa do tamanho de parcela para avaliar a fitomassa fresca de plantas de alface e a massa de frutos de pimentão, de tomateiro, de feijão-vagem e de abobrinha italiana. Ensaios de uniformidade com 27 unidades básicas (27 plantas) são suficientes para estimar o tamanho de parcela para avaliar a fitomassa fresca de plantas de alface com amplitude do intervalo de confiança de 95% menor ou igual a duas unidades experimentais básicas. Ensaios de uniformidade de pimentão com 29 unidades básicas (29 plantas) em estufa plástica, de tomateiro com 12 unidades básicas (12 plantas) em túnel plástico e de feijão-vagem com 21 unidades básicas (42 plantas) em túnel plástico, são suficientes para estimar o tamanho de parcela para avaliar a massa de frutos com amplitude do intervalo de confiança de 95% menor ou igual a duas unidades experimentais básicas. Ensaios de uniformidade de feijão-vagem com 18 unidades básicas (36 plantas) e de abobrinha italiana com dez unidades básicas (dez plantas) em estufa plástica são suficientes para estimar o tamanho de parcela para avaliar a massa de frutos com amplitude do intervalo de confiança de 95% menor ou igual a três unidades experimentais básicas. Recomenda-se o uso de parcelas com seis unidades experimentais básicas para avaliar a fitomassa fresca de plantas de alface e com sete, cinco, seis e oito unidades experimentais básicas, respectivamente, para avaliar a massa de frutos de pimentão, de tomateiro, de feijão-vagem e de abobrinha italiana.
352

Potencial de uso agrícola e qualidade de cozimento de cultivares crioulas de feijão / Agronomic performance and cooking quality of common bean land varieties

Morais, Narielen Moreira de 04 December 2013 (has links)
The potential use of common bean land varieties regarding to agronomic performance and cooking quality was little evaluated by plant breeding programs. Therefore, objectives of this study were to evaluate the phenological, morphological, grain yield, absorption percentage and cooking quality characters of common bean land varieties obtained from different location; to study the correlations between phenological, morphological and grain yield characters; to estimate the direct and indirect effects of the characters on grain yield; to select common bean land varieties with high agronomic performance and reduced cooking time for family farms grown and for crosses in plant breeding programs. For this, 23 common bean cultivars, being nineteen land varieties and four cultivars developed by research, were evaluated in field experiments installed at the Federal Institute Farroupilha (IFF), Alegrete, and at Federal University of Santa Maria (UFSM), Santa Maria, in growing season 2012/2013. A significant cultivar x location interaction was observed for the characters number of days from emergence to flowering, cycle, height of insertion of the first pod, height of insertion of the final pod, number of pods per plant, grain yield, b* chromaticity value, absorption percentage and cooking time. Preto Miúdo and Cavalo Rajado land varieties showed high grain yield and agronomic characters desirable for grown. The Banana and Perdiz land varieties showed reduced cooking time, however, presented low agronomic performance and type of grain out of commercial standards, which makes difficult its indication for grown. The number of pods per plant showed positive linear correlation of intermediate magnitude with the grain yield (r = 0.670), and the highest direct effect (0.632). There is presence of genetic variability among the common bean land varieties studied, which enables obtaining genetic gain in breeding programs using this germplasm. The indirect selection for the number of pods per plant is important component in predicting grain yield in common bean land varieties. Preto Miudo and Cavalo Rajado land varieties show high agronomic performance and its use is indicated for cultivation on family farms and for crosses in plant breeding programs. / O potencial de uso das cultivares crioulas de feijão quanto ao desempenho agronômico e a qualidade de cozimento foi pouco avaliado pelos programas de melhoramento. Sendo assim, foram objetivos deste trabalho avaliar os caracteres fenológicos, morfológicos, da produção, da porcentagem de absorção e de qualidade de cozimento de cultivares crioulas de feijão obtidas em diferentes locais; estudar as correlações fenotípicas entre os caracteres fenológicos, morfológicos e da produção; estimar os efeitos diretos e indiretos dos caracteres avaliados sobre a produtividade de grãos; selecionar cultivares crioulas de feijão com elevado desempenho agronômico e reduzido tempo de cozimento para cultivo na agricultura familiar e para uso em cruzamentos dirigidos em programas de melhoramento. Para tanto, 23 cultivares de feijão, sendo 19 crioulas e quatro desenvolvidas pela pesquisa, foram avaliadas em experimentos de campo instalados em área do Instituto Federal Farroupilha (IFF), Alegrete, e da Universidade Federal de Santa Maria (UFSM), Santa Maria, no cultivo de safra 2012/2013. Interação cultivar x local significativa foi observada para os caracteres número de dias da emergência à floração, ciclo, altura de inserção da primeira vagem, altura de inserção da última vagem, número de vagens por planta, produtividade de grãos, valor de cromaticidade b*, porcentagem de absorção e tempo de cozimento. As cultivares crioulas Preto Miúdo e Cavalo Rajado apresentaram alta produtividade de grãos e caracteres agronômicos desejáveis para o cultivo. As cultivares Banana e Perdiz apresentaram tempo de cozimento reduzido, porém desempenho agronômico inferior e tipo de grão fora de padrões comerciais, o que dificulta a sua indicação para o cultivo. O número de vagens por planta apresentou correlação linear positiva de intermediária magnitude com a produtividade de grãos (r= 0,670) e o maior efeito direto (0,632) Variabilidade genética é observada entre as cultivares crioulas de feijão avaliadas, o que possibilita a obtenção de ganhos genéticos em programas de melhoramento com o uso deste germoplasma. A seleção indireta pelo número de vagens por planta é indicada na predição da produtividade de grãos em cultivares crioulas de feijão. As cultivares Preto Miúdo e Cavalo Rajado apresentam alto desempenho agronômico e seu uso é indicado para cultivo na agricultura familiar e para uso em programas de melhoramento.
353

Seleção de linhagens de feijão para produção, acúmulo e eficiência de uso de fósforo na planta / Selection of common bean lines for grain yield, accumulation and phosphorus use efficiency in plant

Mambrin, Ritieli Baptista 23 September 2016 (has links)
The use of common bean (Phaseolus vulgaris L.) cultivars efficient and responsive to phosphorus use is important for increase grain yield and reduce production cost. Thus, the objectives of this work were: (1) evaluate the response of common bean lines in production of dry matter, grain yield components, and accumulation of phosphorus in the plant under different phosphorus availability; (2) investigate the association between these characters; (3) evaluate the genetic variability of common bean lines as the phosphorus availability; (4) identify efficient lines in phosphorus use and responsive to application of mineral by different indexes. For this, four experiments were carried out in a greenhouse of the Plant Science Department at the Santa Maria Federal University during the years 2013 2015, in a completely randomized design in a sub-sub-divided plot. In the first two experiments the phosphorus concentration tested in the nutrient solution were from 0.5 to 2.3 mmol L-1 as part of the main plot; Perola and IPR88 Uirapurú cultivars were evaluated in the sub-plot, and the growing seasons (fall-winter and spring-summer) in the sub-sub-plot. In the third and four experiments were evaluated the efficiency of phosphorus use and 12 genotypes response the low (0.9 mmol L-1) and high (1.9 mmol L-1) phosphorus concentration in the nutrient solution in two growing seasons. Phosphorus concentration in the nutrient solution from 1.33 to 1.84 mmol L-1 provided higher dry mass of pod at pod filling stage (R8), high dry mass of grains at maturation (R9), and higher number of grains and grain yield, for Pérola and IPR88 Uirapurú cultivars. Phosphorus concentration in the nutrient solution from 1.37 to 1.96 mmol L-1 result in high phosphorus concentration in: leaves at first trifoliate leaf (V4), stem at flowering (R6);,leaves, stem and pods at pod filling (R8), grains at maturation (R9), and high grain yield and phytic acid, in growing seasons (fall-winter and spring-summer). The characters dry mass of the leaves, stem and pods at pod filling stage (R8), dry mass of grains at maturity (R9), number of grains and number of pods are promising for allowing indirect selection. The evaluation of the phosphorus concentration in plant tissues at pod filling stage (R8) is promising and allowing indirect selection for the grain yield in common bean. The L 2225, L 2632, L 2527 and L 2411 lines, stood out due to high production of dry mass of stem in low phosphorus concentration in the culture medium. There is genetic variability among common bean lines studied for dry matter production, grain yield and phosphorus accumulation in tissues. The L 2527 line proved to be efficient and responsive for phosphorus use. / O uso de cultivares de feijão (Phaseolus vulgaris L.) eficientes e responsivas a utilização de fósforo é importante para a elevação da produtividade de grãos e para a redução do custo de produção. Diante disso, os objetivos desse trabalho forma: (1) avaliar a resposta de linhagens de feijão submetidas a diferentes disponibilidades de fósforo na produção de massa seca, nos componentes da produtividade de grãos e no acúmulo de fósforo na planta; (2) investigar a associação entre esses caracteres; (3) avaliar a variabilidade genética de linhagens de feijão quanto à disponibilidade de fósforo; (4) identificar linhagens eficientes no uso de fósforo e responsivas a aplicação deste mineral por diferentes índices. Para isso, os experimentos foram desenvolvidos em casa-de-vegetação do Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM), durante os anos de 2013 a 2015, em delineamento inteiramente casualizado e parcela sub-sub-dividida. Nos dois primeiros experimentos foram testadas concentrações de fósforo na solução nutritiva de 0,5 a 2,3 mmol L-1 como componentes da parcela principal; as cultivares Pérola e IPR88 Uirapurú na sub-parcela e, os cultivos de outono-inverno e primavera-verão na sub-sub-parcela. No terceiro experimento foram avaliadas a eficiência no uso de fósforo e a resposta de 12 genótipos de feijão em baixa (0,9 mmol L-1) e em alta (1,9 mmol L-1) concentração de fósforo na solução nutritiva, em duas épocas de cultivo. Concentrações de fósforo na solução nutritiva entre 1,33 e 1,84 mmol L-1 proporcionam maior massa seca das vagens no enchimento das vagens (R8), dos grãos na maturação (R9), número de grãos e produtividade de grãos, para os genótipos Pérola e IPR88 Uirapurú, nos cultivo de outono- inverno e primavera-verão. Concentrações de fósforo na solução nutritiva entre 1,37 e 1,96 mmol L-1 acarretam maior concentração de fósforo: nas folhas em terceira folha trifoliada (V4), no caule em floração (R6), nas folhas, caule e vagens em enchimento de vagens (R8) e nos grãos na maturação (R9); produtividade de grãos e concentração de ácido fítico dos grãos, nos cultivos de outono-inverno e primavera-verão. Os caracteres de massa seca das folhas, caule e vagens no enchimento de vagens (R8), massa seca dos grãos na maturação (R9), número de grãos e número de vagens são promissores por permitir seleção indireta. Assim como, a avaliação da concentração de fósforo nos tecidos vegetais no estádio enchimento de vagens (R8) é promissora e permite seleção indireta para a produtividade de grãos. As linhagens L 2225, L 2632, L 2527 e L 2411, destacaram-se por apresentar alta produção de massa seca de caule em baixa concentração de fósforo no meio de cultivo. Existe variabilidade genética entre as linhagens de feijão estudadas, para produção de massa seca, produtividade e acúmulo de fósforo nos tecidos. A linhagem L 2527 mostrou-se eficiente e responsiva ao uso de fósforo para a parte aérea.
354

Participação dos polissacarídeos de parede celular no fenômeno de endurecimento de feijões (Phaseolus vulgaris L.) - cv Carioca-Pérola / The participation of the cell wall polysaccharides in common beans (Phaseolus vulgaris L. - cv Carioca-Pérola) hardening

Tânia Misuzu Shiga 29 April 2003 (has links)
O feijão é um alimento nutritivo amplamente consumido no Brasil, porém, apresenta facilidade para desenvolver o defeito textural hard-to-cook (HTC) que torna as sementes resistentes ao amaciamento por cocção e provoca perdas econômicas e nutricionais. A maciez, um atributo importante nos grãos, proporciona melhor aceitabilidade do produto pelo consumidor, melhor qualidade nutricional e organoléptica e menor gasto de tempo e combustível no preparo. Devido à importância da parede celular na textura dos alimentos, foram investigadas alterações na estrutura e composição de seus polissacarídeos causada pelo HTC. Com este intuito, feijões Carioca-Pérola foram armazenados por 8 meses à 30°C / 75% UR e amostras cruas e cozidas tiveram suas paredes celulares extraídas através de tratamento enzimático-químico, produzindo uma fração solúvel em água (FSA) e outra insolúvel, denominada fração insolúvel em água (FIA). A FIA foi fracionada resultando em polímeros solúveis em solução de quelante de CDTA (FCDTA), base fraca (FBF) e álcali 4M (H4). A FSA foi separada em coluna de troca aniônica e os polímeros assim obtidos foram tratados com celulase e endopoligalacturonase e analisados quanto ao conteúdo de açúcares, peso molecular e natureza das ligações através de cromatografia em fase gasosa e a líqüido e por espectrometria de massa. Os resultados revelaram que 75% da parede celular do cotilédone é constituída pelas frações FSA, H4 e FCDTA, ricas em arabinanos ramificados de elevado peso molecular, contendo pequenas quantidades de xiloglicanos (XG), arabinogalactanos tipo II (AGII), galactanos, ramnogalacturonanos (RG) e xilogalacturonanos (XGA). As cascas dos feijões eram compostas por xilanos, celulose, XG, arabinanos e por pequena quantidade de RG. As sementes HTC possuem menor quantidade de polissacarídeos solúveis em água (FSA) e em solução de CDTA (FCDTA) e maior quantidade de material insolúvel em água (FIA), principalmente, polímeros da fração H4. Os feijões normais perdem grande quantidade de material péctico durante a cocção através da despolimerização e solubilização das pectinas hidrossolúveis (FSA) e, principalmente, pela solubilização dos polissacarídeos provenientes da fração H4, entretanto, a perda de material péctico em amostras HTC é mínima. Os feijões envelhecidos podem apresentar menor grau de metil esterificação das pectinas, que impediria a despolimerização. A redução na solubilidade dos polímeros da fração H4 pode estar relacionada com a perda de ramificação dos arabinanos e xiloglicanos resultando em polissacarídeos com cadeias mais lineares, que causam alinhamento das cadeias e formação de interações do tipo ponte de H, tornando os polímeros menos solúveis. O aumento de XGA e AU nas frações pécticas da FSA, bem como na FCDTA e FBF reforçam a suposição. / Beans is a nourishing food source widely consumed in Brazil. However, they show tendency to develop easily the textural defect named Hard-to-cook (HTC) that becomes the seeds resistant to softening by cooking, causing economical and nutritional losses. Softness is an important quality attribute of pulses that increases acceptability by consumer and provides betters nutritional and organoleptical qualities that results in less time and fuel spent. Because the importance of the cell wall to the food texture, changes in its polysaccharide structure and composition were investigated during the development of HTC. With this aim, Carioca-Pérola beans were stored for 8 months at 30°C / 75% RH and raw and cooked samples have had the cell wall extracted by enzymatic-chemical treatment, producing a water soluble fraction (FSA) and a water insoluble fraction, named water insoluble fraction (FIA). The FIA was fractionated, producing CDTA soluble polymers, weak base soluble polymers (FBF) and 4M alkali-soluble fraction (H4) The FSA was separated using anion exchange chromatography. All fractions obtained were treated withcelulase and endopoligalacturonase and analyzed for sugar content, molecular weight and sugar linkage using gas and liquid chromatography and mass spectrometry. The results revealed that FSA; H4 and CDTA fractions composed 75% of the cell wall material. This fractions were rich in high molecular weight branched arabinans, and also contained small amounts of xyloglucans (XG), arabinogalactans type II (AGII), galactans, rhamnogalacturonans (RG) and xylogalacturonans (XGA). Xylans, cellulose, XG, arabinans and small amounts of RG composed beans hulls cell wall. The HTC seeds have less amounts of CDTA and water-soluble polysaccharides (FCDTA and FSA) and higher amounts of water insoluble material (FIA), especially polysaccharides of H4 fraction. Normal beans loss high amounts of pectic material during cooking by water soluble pectin depolymerization and solubilization, and mainly by H4 fraction polysaccharide solubilization. However, the loss of pectic material in HTC beans is minimal. Aged beans pectins could have less methylesterification degree and, therefore, less depolymerization. The loss in H4 fractions polymers solubility could be related with the loss of arabinans and XG branches, resulting in a straight polysaccharide backbone, that cause chains alignment and H bonds formation, produce less soluble structures. The increase in the amounts of XGA and UA in FSA and also in the FCDTA and FBF fractions corroborates the supposition.
355

Myélinisation des projections corticales visuelles de la souris

Roy, Jolanie 10 1900 (has links)
La gaine de myéline qui entoure les axones joue plusieurs rôles, comme l’accélération de la propagation de l’influx nerveux, la synchronisation des aires corticales, la plasticité, un support métabolique, etc. Sa dégénérescence lors de certaines pathologies, comme la sclérose en plaques, cause d’importants problèmes dont des déficits de la coordination motrice et de la démence. C’est pourquoi il est important de comprendre l’origine et la nature des axones myélinisés. L’objectif de ce mémoire est de voir si les axones des projections sensorielles corticocorticales sont myélinisés. Pour ce faire, des injections de Phaseolus vulgaris leucoagglutinine (Phal), un traceur neuronal antérograde, ont été faites dans le cortex visuel primaire de la souris. Les axones marqués et la gaine de myéline ont été révélés avec de l’immunohistochimie dirigée contre le Phal et la protéine de base de la myéline (MBP) respectivement. Les coupes ont été observées au microscope confocal pour chercher la colocalisation de Phal et MBP, qui indiquerait la présence d’axones myélinisés. Plusieurs axones corticocorticaux ipsilatéraux cheminent dans la matière grise. De ces axones, étonnamment peu d’axones myélinisés ont été trouvés. La myélinisation des axones qui s’engageaient dans la matière blanche a été plus difficile à déterminer avec certitude. Certains segments d’axones Phal+ clairement sans myéline ont été observés. Puisque la densité de MBP de la matière blanche était trop élevée, il était impossible de déterminer la colocalisation du Phal et MBP sur des axones individuels. La microscopie électronique a permis de voir des axones marqués individuellement myélinisés dans la matière blanche. / Myelin that ensheathes neuronal axons plays many roles. It increases propagation speed of action potentials and contributes to synchronizing activity between cortical areas. Myelin is plastic and provides a metabolic support for axons. Many diseases, like multiple sclerosis, are linked to the loss of the myelin sheath around axons. For that, it is important to better understand the nature of myelinated axons. Our objective here is to determine whether axons of sensory cortico-cortical projections, are myelinated. To achieve this goal, injections of the anterograde neuronal tracer, leucoagglutinin of Phaseolus vulgaris (Phal) were made in the primary visual cortex of mice. Double immunohistochemistry was used to reveal axons labeled with Phal combined with visualisation of the myelin basic protein (MBP). Sections were observed under a confocal microscope to find colocalization of Phal and MBP staining. Many ipsilateral corticocortical axons travel in the gray matter. Of these, surprisingly few myelinated axons were seen. Determining myelination of Phal labeled axons within the white matter tracts and external capsule was more difficult. The MBP staining of white matter was too dense to allow to unambiguously determine whether individual axons were myelinated. However, some clearly unmyelinated axons were observed therein. To solve this ambiguity, electron microscopic analysis was performed. Myelinated Phal-labeled axons were observed in the EC with electron microscopy.
356

Entwicklung eines FISH-Referenzkaryotyps der Zuckerrübe (Beta vulgaris) für die Integration genetischer Kopplungskarten und die Analyse der chromosomalen Verteilung von repetitiven Sequenzen

Päsold, Susanne 19 December 2013 (has links)
Die Verbindung von genetischen, physikalischen und zytologischen Daten ist entscheidend für die Genom- und Chromosomenanalyse. Obwohl Beta vulgaris (2n = 18) als wichtige Kulturpflanze und Untersuchungsobjekt der Grundlagenforschung eine intensiv analysierte Art darstellt, existiert bisher keine Verknüpfung zwischen Kopplungsgruppen (LG) und Chromosomen. B.-vulgaris-Chromosomen können zudem aufgrund fehlender morphologischer Unterscheidungsmerkmale bisher nicht einzeln identifiziert und klassifiziert werden. Somit sind zytogenetisch gewonnene Ergebnisse nicht ohne weiteres auf genetische Kopplungsgruppen und physikalische Karten übertragbar. Zytogenetische Methoden können zur Analyse struktureller Chromosomenveränderungen, zur Identifizierung und Lokalisierung von repetitiver DNA sowie zur Kartierung schwierig zu positionierender Marker verwendet werden. Ziel dieser Arbeit war es daher, ein FISH (Fluoreszenz-in-situ-Hybridisierung)-Verfahren zu etablieren, das die Kopplungsgruppen und Chromosomen der Zuckerrübe korreliert und die mikroskopische Identifizierung aller Chromosomenarme ermöglicht. Im Rahmen dieser Arbeit wurde ein FISH-Referenzkaryotyp der Zuckerrübe entwickelt. Durch ein Sondenset aus 18 BACs (bacterial artificial chromosome) sind alle Chromosomenarme der Zuckerrübe identifizierbar und werden mit den nördlichen und südlichen Enden der genetischen Kopplungsgruppen verknüpft. Somit ist eine einheitliche Nummerierung von Kopplungsgruppen und Chromosomen möglich. Durch die gleichzeitige Hybridisierung von chromosomenspezifischen BACs und den Satelliten-DNA-Sonden pAv34 und pBV VI beziehungsweise pEV und pBV wurden die Verteilungsmuster der Sequenzfamilien auf den Chromosomen ermittelt. Die gleichzeitige Hybridisierung aller vier repetitiven Sonden ergab ein chromosomenspezifisches Muster aus subtelomerischen, interkalaren und zentromerischen Signalen. Damit ist die Identifizierung aller B.-vulgaris-Chromosomen in einem einzelnen FISH-Experiment möglich. Zudem wurden dadurch die Chromosomen mit hohem Anteil an tandemartig angeordneten repetitiven Sequenzen identifiziert und die Chromosomenregionen lokalisiert, welche die Sequenzassemblierung behindern können. Sowohl das entwickelte BAC-Set als auch der Sondenpool aus repetitiver DNA unterscheiden die somatischen Metaphasechromosomen erstmals unabhängig von trisomen Linien. Da mit Hilfe der Satelliten-DNA-Sonden alle Chromosomen gleichzeitig markiert werden können, waren die spezifischen physikalischen Längen ermittelbar. Sie wurden mit den genetischen Längen der Kopplungsgruppen in Verbindung gebracht und deckten eine kopplungs-gruppenspezifische Rekombinationshäufigkeit zwischen 0,73 und 1,14 Mb/cM auf. Durch Hybridisierung der BACs und subtelomerischer beziehungsweise telomerischer Sonden auf Pachytänchromosomen wurde der Abstand der BACs sowie der in ihnen enthaltenen genetischen Marker zum physikalischen Chromosomenende abgeschätzt. An fünf Chromo-somenenden wurde ein deutlicher Abstand zwischen den Signalen des BACs und der terminalen Sonden festgestellt. Die zugehörigen Kopplungsgruppen sind demnach erweiterbar. Zudem wurden drei BACs mit nicht detektierbarem Abstand zum Chromosomenende durch FISH an gestreckten Chromatinfasern näher untersucht. Einer der drei BACs wurde eindeutig in unmittelbarer Nähe des Telomers nachgewiesen. Für dieses Ende (Chr 2N) ist die Wahrscheinlichkeit gering, dass die Kopplungsgruppe durch zusätzliche Marker erweitert werden kann; sie wird darum als abgeschlossen angesehen. Für die Enden Chr 4S und Chr 9S war der Abstand zwischen BAC und terminaler Sonde zu groß, um ihn durch Fiber-FISH zu ermitteln. Für sie sind weitere distal zu positionierende Marker wahrscheinlich. Weiterhin wurden bioinformatische Analysen an der verfügbaren B.-vulgaris-Genomsequenz RefBeet 1.0 durchgeführt. Scaffolds, welche die genetischen terminalen Marker enthalten, wurden bioinformatisch identifiziert und auf ihren Gehalt subtelomerischer und telomerischer Sequenzen untersucht. Vorhandene terminale Sequenzen sind ein Nachweis für eine terminale Lokalisierung der in-silico-Chromosomenabschnitte. Für drei Scaffolds mit zuvor ungeklärter Lage wurde dadurch das in-silico-Chromosom ermittelt beziehungsweise die nördliche oder südliche Position auf dem Chromosom dargestellt. Durch die Lokalisierung dieser Bereiche innerhalb der Sequenz in Bezug zum genetischen Marker und unter Berücksichtigung der Ergebnisse der Pachytän-FISH wurde die Strangorientierung von 16 Scaffolds ermittelt. Auf 14 Scaffolds wurden die Abstände der Marker zu den terminalen Sequenzen bestimmt. Der Median betrug etwa 196 kb. Für alle Kopplungsgruppenenden außer dem Norden von LG 2 und LG 4 ist das Vorhandensein weiterer distaler genetischer Marker wahrscheinlich. Satelliten-DNA ist innerhalb einer Art meist homogen, kann jedoch chromosomenspezifische Varianten ausbilden. Auf dem BAC-Marker für Chr 2N wurde durch Southern-Hybridisierung die subtelomerische Sequenzfamilie pAv34 detektiert. Von dem betreffenden BAC wurde eine Subklonbank erstellt. Durch Southern-Hybridisierung wurde der pAv34-Gehalt der Subklone analysiert. Positive Klone wurden sequenziert. Dabei wurden vier verschiedene vollständige pAv34-2N-Monomere detektiert. Im Vergleich mit pAv34-Volllängenmotiven aus der RefBeet 1.0 und dem Datensatz der nicht assemblierten Sequenzen der RefBeet 0.2 bilden die pAv34-2N-Einheiten mit pAv34-Kopien, die verschiedenen in-silico-Chromosomen und Contigs zugeordnet sind, eine Subfamilie. Aus den Sequenzen der Subklone wurden zwei Subklon-Contigs gebildet, die im in-silico-Chromosomenabschnitt von Chr 2N (Bvchr2.un.sca001) positioniert wurden. Dadurch wurden Regionen bisher unbekannter Sequenz entschlüsselt. Abweichungen zwischen den assemblierten Daten und den Subklonsequenzen deuten auf Assemblierungsfehler der Genomsequenz in repetitiven Bereichen hin. Die in dieser Arbeit erzielten Ergebnisse ermöglichen erstmalig die eindeutige Identifizierung aller B.-vulgaris-Chromosomen unabhängig vom Zellzyklusstadium und im Einklang mit genetischen Informationen. Zytogenetische sind jetzt mit molekularen Daten integrierbar und können verwendet werden, um den chromosomenspezifischen Satelliten-DNA-Gehalt aufzudecken und mögliche chromosomenspezifische Subfamilien zu identifizieren. Sie erlauben, physikalische Abstände zwischen Markern zu ermitteln und die Abdeckung von Kopplungsgruppen im terminalen Bereich zu untersuchen. Die Ergebnisse tragen dazu bei, Marker und nicht zugeordnete Contigs und Scaffolds zu kartieren, Ursachen für Lücken aufzudecken und damit die Sequenzdaten des Zuckerrübengenoms zu einer fortlaufenden, hochqualitativen Sequenz zu assemblieren. Die zytogenetischen Daten bilden zudem die Basis für zukünftige Untersuchungen struktureller Umbauten von Chromosomen, die während der Genomevolution stattfanden. / The correlation of genetic, physical and cytological data is crucial for interdisciplinary genome and chromosome analyses. Beta vulgaris (2n = 18) is an important crop and an object of basic research. Although it is an intensely analysed species, its genetic linkage groups (LG) have not been assigned to chromosomes. Additionally, sugar beet chromosomes lack distinct morphological features and could therefore not be identified and classified individually. Consequently, results generated by cytogenetic methods can not be readily applied to genetic and physical maps. Cytogenetic approaches enable analysing structural chromosomal changes, identifying and localizing repetitive DNA, and mapping of markers which are difficult to place within linkage maps. Therefore, the main objective of this work has been the development of a FISH (fluorescence in situ hybridization) procedure that correlates LGs with chromosomes of sugar beet and that allows the microscopic identification of individual chromosome arms. In this work a FISH reference karyotype for sugar beet has been established. A set of 18 BACs (bacterial artificial chromosome) allows the unequivocal identification of each sugar beet chromosome and assigns them to the southern and northern ends of LGs. Hence, the chromosomes are numbered in accordance with the genetic map. The arm-specific BACs and the satellite DNA families pBV and pBV VI or pEV and pAv34 have been hybridized simultaneously to assign the distribution patterns of the highly abundant sequence families to chromosomes. Simultaneous hybridization of the four repetitive probes revealed a chromosome-specific pattern of subtelomeric, intercalary and centromeric signals. Thus, each of the sugar beet chromosomes can be identified in a single FISH experiment. Furthermore, chromosomes with a high content of repetitive DNA have been identified and chromosomal regions that may hinder the correct sequence assembly have been localized. The BAC set as well as the pooled satellite DNA probes discriminate the somatic chromosomes for the first time independently from trisomic lines. Since the chromosomes are differentially labelled with the satellite DNA probes their physical distances could be determined and correlated with genetic distances of the corresponding LGs. A LG-specific recombination frequency from 0.73 to 1.14 Mb/cM has been disclosed. BACs and subtelomeric or telomeric sequences have been hybridized simultaneously on pachytene chromosomes to estimate distances between BACs plus the markers they contain and the physical chromosome ends. Five BACs showed substantial distances to the physical chromosome ends; the corresponding LGs could thus be extended by additional markers. Furthermore, three BACs showing only minor distances to chromosome ends have been investigated in detail by fiber-FISH. One of these BACs was localized closely adjacent to the telomere. For this chromosome end (Chr 2N) it is unlikely that the LG could be extended distally by additional markers and is therefore considered to be closed. The BACs for the chromosome ends Chr 4S and Chr 9S have been too distant from the terminal probe to be bridged by fiber-FISH. For them it is likely that further markers can be placed distally. Furthermore, the B. vulgaris genomic sequence RefBeet 1.0 has been investigated. Scaffolds containing terminal genetic markers have been identified bioinformatically and analysed for the content of subtelomeric and telomeric sequences. The occurrence of terminal sequences confirms the terminal localization of in silico chromosome segments. Three scaffolds with an initially unknown position could thus be allocated to in silico chromosomes and to the northern or southern position on the chromosome. The strand orientation of 16 scaffolds has been determined based on the localization of terminal sequences in relation to the genetic marker considering the results of FISH on pachytene chromosomes. The distance between markers and terminal sequences has been determined for 14 scaffolds. The median is 196 kb. It is likely that further markers can be placed distally from all LG ends except for the north of LG 2 and LG 4. Satellite DNA is usually homogenous within one species; however, it can form chromosome-specific variants. Southern hybridization revealed that the BAC marker for Chr 2N contains the subtelomeric sequence family pAv34. The BAC has been subcloned and the pAv34 content of the subclones has been analysed by Southern hybridization. Positive clones have been sequenced. Thereby, four pAv34-2N monomeres have been detected. Compared to full-length pAv34 motives derived from the RefBeet 1.0 and from unassembled sequence data of the RefBeet 0.2 the pAv34-2N units form a subfamily together with pAv34 copies assigned to different in silico chromosomes and contigs. The subclone sequences have been assembled to two subclone contigs, which have been positioned within the in silico chromosome segment of Chr 2N (Bvchr2.un.sca001). Thereby, regions of unknown sequence have been decoded and probable misassemblies in repetitive regions within the RefBeet 1.0 have been disclosed. The results obtained in this work enable the identification of all sugar beet chromosomes independently from their stage of cell division and in accordance with genetic information. Cytogenetic data are integrated with molecular data and can be used for identifying the chromosome-specific distribution of repeats and chromosome-specific repeat variants. They enable determining physical distances between markers and investigating the terminal coverage of LGs. The results support the correct mapping of markers and unassigned contigs, uncover reasons for gaps within maps and sequence assemblies, and thus contribute to assembling data into a continuous high quality genome sequence of sugar beet. Moreover, the cytogenetic data represent the basis for future investigations of structural chromosomal changes that took place during evolution.
357

Ability of Chlorella vulgaris algae for nutrients removal in domestic wastewater and its collection by ferrate

Tran, Tien Khoi, Truong, Nhat Tan, Nguyen, Nhat Huy 13 May 2020 (has links)
In this study, we aim to employ Chlorella vulgaris algae for removal of nutrients in wastewater and collect the produced algae by ferrate after treatment. The growth of algae was conducted in F/2 synthetic medium and in actual domestic wastewater. The removals of nitrogen and phosphorous by algae were then investigated for low and high nutrient concentrations using wastewater after biological treatment in both batch and continuous experiments. Results showed that specific growth rates in the exponential phase were 0.23 and 0.35 day-1 for F/2 medium and domestic wastewater, respectively, proving the suitability of wastewater for algae growth. The removal efficiency of ammonia, nitrate, and phosphate were 89 - 93, 64 - 76, and 69 – 88%, respectively. In the algae collection test, pH 8 is the optimal pH to remove algae and ferrate had higher algae removal ability than alum under each optimal condition with removal efficiency of 84 - 97% at dosage of 12 mg Fe/L. These results suggest that microalgae is a potential alternative for removing of nutrients in wastewater treatment due to the high uptake capacity of nitrogen and phosphorous and the effective collection of algae after treatment by ferrate. / Mục tiêu của nghiên cứu này là đánh giá hiệu quả xử lý chất dinh dưỡng bằng tảo Chlorella vulgaris trong môi trường nước thải sinh hoạt, thông qua khả năng xử lý N và P từ nguồn nước khi tảo tăng trưởng và khả năng keo tụ để thu hồi tảo bằng ferrate. Tốc độ tăng trưởng đặc thù µ trong môi trường F/2 và nước thải sinh hoạt lần lượt là 0,23 ngày-1 và 0,35 ngày-1. Hiệu suất xử lý ammoni, nitrát và phốt phát- lần lượt đạt 89 - 93%, 64 - 76% và 69 - 88%. Kết quả thí nghiệm keo tụ thu hồi tảo cho thấy pH = 8 là thích hợp nhất để loại bỏ tảo bằng ferrate và việc sử dụng ferrate cho hiệu quả tách tảo tốt hơn phèn nhôm với lượng sử dụng ít hơn. Ở hàm lượng 12 mgFe/L, hiệu quả tách tảo đạt cao nhất từ 84 - 97%. Nghiên cứu cho thấy tiềm năng thay thế công nghệ sinh học truyền thống bằng công nghệ vi tảo trong loại bỏ các chất dinh dưỡng và khả năng thu hồi tảo hiệu quả bằng cách sử dụng ferrate.
358

Crude oil-utilizing strain Desulfovibrio vulgaris D107G3, a mesophilic sulfate-reducing bacterium isolated from Bach Ho gas-oil field in Vung Tau, Vietnam

Nguyen, Thi Thu Huyen, Tran, Thi Kim Thoa, Lai, Thuy Hien 29 December 2021 (has links)
Some of anaerobic, mesophilic sulfate-reducing bacteria that produce H₂S and cause microbial metal corrosion can degrade crude oil in anaerobic conditions. In this study, a mesophilic sulfate-reducing bacterial strain D107G3 isolated from Bach Ho gas-oil field in Vung Tau, Vietnam that is able to utilize crude oil in the anaerobic condition is reported. The strain D107G3 was classified as a Gram-negative bacterium by using Gram staining method. Basing on scanning microscopy observation, the cell of a strain D107G3 had a curved rod shape. The 16S rRNA gene sequence analysis showed that the strain D107G3 was identified as Desulfovibrio vulgaris with 99.7% identity. The suitable conditions for its growth that was determined via estimating its H₂S production was the modified Postgate B medium containing 1% (v/v) crude oil, 1% NaCl (w/v), pH 7 and 300C incubation. In these conditions, the strain D107G3 can consume 11.4 % of crude oil total and oxidize heavy crude oil (≥ C45) for one month at anoxic condition. These obtained results not only contribute to the science but also continue to warn about the dangers of mesophilic sulfate reducing bacteria to the process of crude oil exploitation, use, and storage in Vung Tau, Vietnam. / Trong bài báo này, chủng vi khuẩn khử sunphat (KSF) ưa ấm D107G3 phân lập từ giếng khoan dầu khí mỏ Bạch Hổ, Vũng Tàu, Việt Nam có khả năng sử dụng dầu thô trong điều kiện kị khí được công bố. Chủng D107G3 được xác định là vi khuẩn Gram âm nhờ phương pháp nhuộm Gram. Quan sát trên kính hiển vi điện tử quét cho thấy tế bào chủng D107G3 có hình que cong. Kết quả phân tích trình tự gen 16S rRNA đã xác định được chủng D107G3 thuộc loài Desulfovibrio vulgaris với độ tương đồng 99.7%. Thông qua đánh giá lượng H₂S tạo thành đã khám phá được điều kiện thích hợp cho sinh trưởng của chủng D107G3: môi trường Postgate B cải tiến chứa 1% (v/v) dầu thô, 1 % NaCl (gL⁻¹), pH 7 và nuôi cấy ở 30°C. Trong điều kiện đó, chủng D107G3 đã sử dụng được 11.4 % hàm lượng dầu tổng số, thành phần dầu bị phân huỷ là các n-parafin có mạch C≥45 sau 1 tháng nuôi cấy kỵ khí. Các kết quả này đóng góp về mặt khoa học và tiếp tục cảnh báo mối nguy hại của KSF ưa ấm đến việc khai thác, sử dụng và bảo quản dầu mỏ ở Vũng Tàu, Việt Nam.
359

Etude de la croissance de Chlorella vulgaris en photobioréacteur batch et continu, en présence de concentrations élevées de CO2,

Clement-larosière, Barbara 23 January 2012 (has links) (PDF)
Face à la montée de la prise de conscience des enjeux écologiques actuels, la recherche se tourne vers le développement des bioprocédés pour développer de nouvelles solutions aux problèmes environnementaux. Cette thèse porte sur l'étude de la faisabilité d'un procédé de capture de CO2 à partir de la culture de la microalgue Chlorella vulgaris en photobioréacteur continu. Ce travail a permis d'identifier l'algue C. vulgaris comme une candidate prometteuse pour cette application. En effet C. vulgaris présente une capacité de production de biomasse et de fixation de CO2 très intéressante pour cette application. Les études menées lors de ce travail de thèse ont également permis de mettre à jour les interactions complexes entre les cellules algales et le CO2 présent à de fortes concentrations. De même, elles ont apporté un approfondissement à la compréhension des verrous existants pour le développement d'un procédé de captage du CO2 et de la nécessité de prendre en compte tous les paramètres de culture (lumière, concentration en nitrate). A partir des études menées, il a été possible de proposer un modèle pour la croissance de C. vulgaris en photobioréacteur continu. Bien que de futures études soient encore nécessaires pour être en mesure de parfaitement modéliser le comportement de l'algue lors de cultures en photobioréacteur, ce modèle présente une bonne corrélation avec les expérimentations. Enfin une étude de pré-dimensionnement a été proposée qui a permis de mettre en lumière les nombreux points d'interrogations encore existants avant d'être en mesure d'adapter le procédé de laboratoire à une échelle industrielle
360

The population dynamics, parasites and predators of aphids, with particular reference to the peach-potato aphid, Myzus persicae (Sulzer), on brussels sprouts in the Edinburgh area

Agyen-Sampong, Martin January 1972 (has links)
Investigations were carried out on the seasonal changes of aphids, particularly Myzus persicae (Sulz.), on hrussels sprouts and the importance of their natural enemies, from autumn 1968 to spring 1971 in the area around Edinburgh. M. persicae overwintered anholocyclically on weeds, particularly on dock plants, hut rarely on brassica crops. Plants in glasshouses also provided overwintering sites for M. persicae and Macrosiphum euphorbiae (Thomas). These aphids started gradually to infest the brussels sprout plants during the end of June in a constant but irregular movement. Both M. persicae and M.euphorbiae have no fixed patterns of population changes throughout the field nor from year to year. During early July the initially low densities of M. persicae and M. euphorbiae populations increased fast. By early August parasitism and predation increased; condensation of water droplets on the aphids also appeared in August and drowned some of them. Subsequently these mortality factors caused a sharp decline of the first peak of M. persicae abundance, and complete disappearance of H. euphorbiae from the field by mid-September. Favourable weather and reduced activities of natural enemies caused another peak of M. persicae to be reached in September. A slight drop in abundance occurred again, due mainly to parasitism; the third and last peak of a season appeared during late October and early November. The fall of this peak was attributed to the cold weather which reduced the rate of reproduction and hastened the abscission of bottom leaves which carried the aphid population. Eighteen species in eight genera of aphid parasites and at least eight species in five genera of hyperparasites were recorded. All the eleven species of primary parasites and five genera containing at least eight species of hyperparasites noted as parasites of M. persioae; and fifteen species of primary parasites and five genera of at least eight species of the hyperparasites listed tinder M. euphorbias were first records of any such parasites in Scotland. The M. persicae records as aphid host of seven species of primary parasites and two genera of at least three species of hyperparasites; and M. euphorbiae also as an aphid host of seven species of primary parasites and two genera of at least four species of hyperparasites were new records in Britain. Three and four species of primary parasites listed respectively under M, persicae and M. euphorbiae as aphid host were found to he new records in the general literature. Praon volucre (Hal.) was the dominant species of the primary parasites followed by Diaeretiella rapae Mcintosh and Aphidius picipes (Hees) which were about half and one third as numerous as the dominant species. Asaphes vulgaris Walker was the dominant species of the hyperparasites with cynipids about equally abundant. Some aspects of the bionomics of hyperparasites and primary parasites, particularly P. volucre, were given. Factors which limited the effectiveness of the parasites, particularly P. volucre, included 1. the fast developmental rate and the lower threshold of the aphid host (M, persicae) as compared to that of thep parasite (P. volucre). 2. hyperparasitism; - in 1969 and 1970 aphids on brussels sprouts were hyperparasitised respectively to the extent of 39.4% and 46.9% 3. harvesting of brassica crops during autumn which destroyed some of the aphid mummies and the aphid populations which could be parasitised to increase the numbers of the overwintering mummies. 4. overwintering of the parasites which started during late summer and early autumn while the aphid hosts were reproducing.

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