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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

PROPAGAÇÃO, METABOLISMO SECUNDÁRIO E GENOTOXICIDADE DE Solidago chilensis MEYEN (ASTERACEAE) / PROPAGATION, SECONDARY METABOLISM AND GENOTOXICITY OF Solidago chilensis MEYEN (ASTERACEAE)

Löbler, Lisiane 24 May 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Native medicinal plants are widely used, but are insufficient scientific information on the spread of some species and cytotoxicity. This study investigated the sexual propagation and vegetative species Solidago chilensis Meyen (Asteraceae) through seed germination, micropropagation, cuttings, evaluate the genotoxic and quantify the accumulation of secondary metabolites of plants obtained. Studies of germination in vitro and ex vitro seeds were developed by testing storage conditions, concentrations of gibberellic acid (GA3), light regimes, soaking times in water to 5ºC ± 1ºC, temperatures and populations. For micropropagation were used apical and nodal segments and combinations of benzylaminopurine BAP (0,0 e 2,0 mg L-1) and naphthalene acetic acid NAA (0,0 e 0,2 mg L-1). In the study of stem cuttings were used cuttings of branches overhead and underground rhizomes. Apical, middle and basal branches were kept in distilled water and nutrient solutions Murashige and Shoog (20%), with or without indole butyric acid (IBA) (5,0 mg L-1). For the cutting of rhizomes, segments thereof were immersed in 0, 600 and 1200 mg L-1 IBA for six hours and after cultured in Plantmax, sand or vermiculite. Apical leaves from four different origins: natural plants growing in wasteland; plants from wasteland and cultivated in the greenhouse, plants from cuttings and rhizomes micropropagated plants were collected for the assessment of genotoxicity and quantification of total polyphenols and flavonoids by spectrophotometry, and chlorogenic acid, quercetin and rutin by High Performance Liquid Chromatography Efficiency. The genotoxicity was assessed using the Allium cepa test, testing concentrations of 5 and 20 g L-1 aqueous extracts of dried leaves. Populations influenced the germination of seeds, and the wasteland of the ones who had averaged 57,2% germination. The seeds germinated under 16h photoperiod (2,4% and 22,3%) and continuous darkness (3,5% and 17,6%). The soaking time of 36 hours favored germination (56% and 24,7%) and germination rate in the experiment 2 and 3, respectively. A temperature of 20°C, in experiment 3, provided the highest percentage of seed germination, 26,6%. In micropropagation, the combination of 2,0 mg L-1 of BAP and 0,2 mg L-1 og NAA, provided 49% of complete plants and 37% survival at acclimatization. In cuttings of new shoots, rooting in the substrate occurred over water with the presence of IBA (29%). The Plantmax® provided 62% rooting in cuttings of rhizomes did not differ from sand (43%). In the evaluation of genotoxicity was detected genotoxic potential of extracts derived from micropropagated plants (5 and 20 g L-1) and grown in a greenhouse (5 g L-1). Polyphenols and flavonoids were found in all the extracts and identified flavonoids quercetin and chlorogenic acid in higher concentrations in plants of wasteland, 441,4 and 95,7 mg g-1, respectively, and rutin in similar concentration in all samples (mean 46,9 mg g-1). / Plantas nativas medicinais são amplamente utilizadas, porém as informações científicas são insuficientes sobre a propagação e a citotoxicidade de algumas espécies. Este trabalho objetivou estudar a propagação sexuada e vegetativa da espécie Solidago chilensis Meyen (Asteraceae), através da germinação de sementes, micropropagação e estaquia, além de avaliar o potencial genotóxico e quantificar o acúmulo de metabólitos secundários das plantas obtidas. Estudos da germinação in vitro e ex vitro das sementes foram desenvolvidos testando-se condições de armazenamento, doses de ácido giberélico (GA3), regimes de luz, tempos de embebição em água a 5ºC ± 1ºC, temperaturas e populações. Para a micropropagação, foram utilizados segmentos apicais e nodais e combinações de benzilaminopurina BAP (0,0 e 2,0 mg L-1) e ácido naftaleno acético ANA (0,0 e 0,2 mg L-1). No estudo da estaquia foram utilizadas estacas de ramos aéreos e de rizomas subterrâneos. Porções apicais, medianas e basais de ramos foram mantidas em água destilada e soluções nutritivas de Murashige e Shoog (20%), contendo ou não ácido indol butírico (AIB) (5,0 mg L-1). Para a estaquia de rizomas, segmentos dos mesmos foram imersos em 0, 600 e 1200 mg L-1 de AIB por seis horas e após cultivados em Plantmax®, areia ou vermiculita. Folhas apicais de quatro procedências: plantas crescendo naturalmente em terreno baldio; plantas oriundas de terreno baldio e cultivadas em casa de vegetação; plantas obtidas das estacas de rizomas e plantas micropropagadas foram coletadas para a avaliação da genotoxicidade e quantificação de polifenóis totais e flavonoides por espectrofotometria, além de ácido clorogênico, quercetina e rutina por Cromatografia Líquida de Alta Eficiência. A genotoxicidade foi avaliada através do teste Allium cepa, testando-se concentrações de 5 e 20 g L-1 de extratos aquosos das folhas secas. As populações influenciaram na germinação de sementes, sendo as de terreno baldio as que apresentaram em média 57,2% de germinação. As sementes germinaram sob fotoperíodo de 16 horas (em média 2,4% e 22,3%) e escuro contínuo (em média 3,5% e 17,6%) no experimento 1 e 3, respectivamente. A embebição por 36 horas favoreceu a germinação (56% e 24,7%) e velocidade de germinação no experimento 2 e 3, respectivamente. A temperatura de 20ºC, no experimento 3, proporcionou a maior porcentagem de germinação das sementes, 26,6%. Na micropropagação, a combinação de 2,0 mg L-1 de BAP + 0,2 mg L-1 de ANA, proporcionou 49% de plantas completas e 37% de sobrevivência na aclimatização. Na estaquia de ramos aéreos, ocorreu superior enraizamento no substrato água com a presença de AIB (29%). O substrato Plantmax® proporcionou 62% de enraizamento nas estacas de rizomas, não diferindo da areia (43%). Na avaliação da genotoxicidade, foi detectado potencial genotóxico dos extratos oriundos das plantas micropropagadas (5 e 20 g L-1) e das cultivadas em casa de vegetação (5 g L-1). Polifenóis e flavonoides foram encontrados em todos os extratos, sendo identificados, os flavonoides, ácido clorogênico e quercetina em maior concentração nas plantas de terreno baldio, 441,4 e 95,7 mg g-1, respectivamente, e rutina em concentração semelhante em todas as amostras (em média 46,9 mg g-1).
112

Enxertia de mesa, estaquia e fenologia do caquizeiro em regiões tropicais /

Bezerra, Marcelo Rondon. January 2007 (has links)
Orientador: Aparecida Conceição Boliani / Banca: Luiz de Souza Corrêa / Banca: Silvia Correa Santos / Resumo: Embora a quase totalidade da produção nacional de caqui (Diospyros kaki L.) seja destinada ao mercado interno, o Brasil vem se consolidando nos últimos anos como país exportador dessa fruta para países dos continentes americano e europeu. Por essa razão, o cultivo dessa fruteira vem se constituindo numa importante atividade agrícola para pequenos produtores no Brasil. A obtenção de mudas de boa qualidade para a implantação de pomares constitui-se em sério problema para os fruticultores que pretendem cultivar o caquizeiro, métodos alternativos para a produção de mudas, amenizariam essa dificuldade. Em função disso o presente trabalho objetivou avaliar a porcentagem de pegamento da enxertia de mesa em estacas lenhosas oriundas das brotações do porta-enxerto, a capacidade de enraizamento de estacas lenhosas e herbáceas de caquizeiro oriundas de brotações da copa e do porta-enxerto, ambos da cultivar Rama-Forte, determinar a concentração mais adequada de indolbutírico (AIB) e ainda avaliar a fenologia de dez variedades de caquizeiro (Pomelo, Rubi, Fuyuhana, Rama Forte, Taubaté, Giombo, Suruga, Toote, Fuyu, e Jiro), selecionar aquelas que apresentem melhores características agronômicas e que sejam adaptadas às regiões de clima tropical. O trabalho foi conduzido no período de 16 de março de 2006 a 29 de maio de 2007 na área experimental da Fazenda de Ensino, Pesquisa e Extensão da Universidade Estadual Paulista - Campus de Ilha Solteira, localizada no município de Selvíria - MS. Para a enxertia de mesa foram utilizadas 120 estacas lenhosas oriundas do porta-enxerto onde foi realizada a enxertia por garfagem tipo fenda cheia e divididos em quatro tratamentos com três repetições de 10 estacas, sendo três concentrações de AIB (1500, 2500 e 3500 mgL-1) e a testemunha (sem aplicação de AIB), imergindo-se 5cm da base por cinco minutos na solução...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Although almost the totality of the national production of Kaki (Diospyros kaki L.) either destined to the domestic market, Brazil comes if consolidating in the last years as exporting country of this fruit for countries of the American and European continent. Therefore, the culture of this fruit comes if constituting in an important agricultural activity for small producers in Brazil. The attainment of props of good quality for the implantation of orchards consists in serious problem for the producers of fruits that they intend to cultivate the Japanese Persimmon Tree. The present work objectified to evaluate the percentage of the bench graft in deriving rootstocks props, the shoots of the rootstocks, the capacity of grafting of deriving rootstocks and herbaceous props of Japanese Persimmon Tree of shoots of the pantry and the rootstocks, both of cultivating Rama Forte, to determinate the indolbutiric concentration most adequate (IBA) and still the phenology of ten varieties of Japanese Persimmon Tree (Pomelo, Ruby, Fuyuhana, Rama Forte, Taubaté, Giombo, Suruga, Toote, Fuyu, and Jiro), to select those that present good characteristics and that the regions of tropical climate are adapted. The work was lead of day 16 of March of 2006 until day 29 of May of 2007 in the experimental area of the Farm of Education, Research and Extension of the São Paulo State University - Campus of Ilha Solteira, located in the city of Selvíria-MS. In the bench graft 120 deriving rootstocks props of the rootstocks had been used where type full crack and divided in four treatments with three repetitions of 10 props was carried through by full crack, being three concentrations of IBA (1500, 2500 and 3500 mgL-1) and the witness (without IBA application), immerging 5cm of the base per five minutes into the solution...(Complete abstract click electronic access below) / Mestre
113

Caracterização de cascalhos de perfuração de poços de petróleo por técnicas analíticas instrumentais. / Characterization of petroleum well drill cutting by instrumental analytical techniques.

Thais Bortotti Fagundes 13 April 2018 (has links)
O presente trabalho visou a caracterização dos cascalhos de perfuração de um poço de petróleo pertencente à Bacia de Santos, utilizando diferentes técnicas analíticas instrumentais. O enfoque foi dado a aplicação da difração de raios X como alternativa às práticas de estudo rotineiramente aplicadas na cabine de mud-logging, onde essencialmente são efetuadas classificações visuais das unidades litológicas do poço e geralmente em amostras de granulação fina, conferindo incertezas às descrições. Um total de 164 amostras de cascalhos foram analisadas quimicamente por espectroscopia por fluorescência de raios X e classificadas de acordo com suas similaridades mineralógicas utilizando o recurso de análise estatística multivariada de dados de difração de raios X. Esse recurso permitiu minimizar o conjunto de amostras para os estudos seguintes de caracterização. A definição e a quantificação dos minerais constituintes das amostras, assim como a determinação dos tamanhos e das formas das partículas por análise dinâmica de imagens foram efetuadas apenas em amostras representativas de cada um dos grupos de similaridades definidos. Os resultados foram comparados com os dados do perfil de acompanhamento geológico (dados de perfuração) e com as interpretações realizadas na cabine de mud-logging pelo geólogo, sendo identificada uma elevada correlação entre esses dados. A avaliação da viabilidade de utilização de difratômetros de bancada durante a etapa de perfuração de um poço de petróleo foi também verificada considerando o levantamento de procedimentos de preparação amostras viáveis de serem aplicados no local (tempo adequado de pulverização e eventuais erros de amostragem) e a qualidade das respostas obtidas por diferentes equipamentos de difração de raios X (condições de análise e resolução de picos). O uso de difratômetros de bancada no estudo de cascalhos de perfuração se mostrou viável do ponto de vista operacional, trazendo diversas vantagens para a correta caracterização dos fragmentos, com melhor acurácia nos resultados, diminuição das incertezas e se mostrando uma ferramenta muito ágil. / The present research aimed at characterization of the drill cuttings of an oil well belonging to the Santos Basin, using different instrumental analytical techniques. The main focus was given to the application of X-ray diffraction as an alternative to the routinely applied mud-logging study practices, where essentially visual classifications of the lithological units of the well are carried out and generally in fine granulation samples, giving uncertainties to the descriptions. A total of 164 samples of drill cuttings were chemically analyzed by X-ray fluorescence spectroscopy and classified according to their mineralogical similarities using the multivariate statistical analysis of X-ray diffraction data. This feature allowed minimizing the sample set for subsequent characterization studies. The identification and quantification mineral phases present in all samples, as well as the determination of the sizes and forms of the particles by dynamic images analysis, were carried out only in representative samples of each one of the defined groups of similarities. Results were compared with the data of the geological monitoring profile (drilling data) and the interpretations carried out in the mud-logging unit by geologist, and a high correlation between these data was identified. The viability of using a bench scale diffractometers during the drilling stage of an oil well was also studied considering the feasibility study on representative samples to be applied on site (adequate pulverization time and possible sampling errors) and quality of the results obtained by different X-ray diffraction equipment (collecting conditions and resolution of spikes). The use of bench diffractometers in the study of drill cutting proved to be feasible from the operational point of view, bringing several advantages for the correct characterization of the fragments, with better accuracy in the results, decrease of the uncertainties and a very agile tool.
114

Aproveitamento do cascalho de perfuração de poços para elaboração de pasta de cimentação primária

Almeida Neto, José Bezerra de 13 June 2017 (has links)
The oil industry, in all its segments has the potential to cause environmental impacts. One major impact on the physical environment, generated by the oil industry, is associated with the drilling of oil wells due to the waste generation, among which are the drilling fluid and cuttings resulting from oil well drilling. It is estimated that in Brazil's Northeast region currently exists a waste quantity in the order of 100,000 m³ coming from land drilled wells for oil production and also due to the increasing well numbers, it is presumed a generating of 50 m³ by year. Due to the drill cuttings amount and its organic and inorganic contaminants generated, as well as the treatment, transportation, disposal and associated costs, there is usually a backset in the solid waste management, such as the adequacy of the drill cuttings produced volume over a period of time versus the evaluation and release times of the destined area to the industrial landfill, by the State's control and inspection, aiming at the reception and maintenance safe of these wastes. The present study aims to analyze the technical feasibility of the drill cuttings wastes adding (DCW) in the cement slurry, used in oil wells. The cement slurry physicochemical properties with drill cuttings depicted in this study are the lab test results carried out to adapt them to the technical parameters established by the oil company. The cement slurry lab tests done were: density, rheology, filtrate, free water, thickening time, stability and compressive strength. Some relevant results are described below. Some relevant results are described below, with the focus on the raise of 8% in the yield of the examined cement slurries with drill cuttings, compared to the conventional cement slurries, for a given density. The compressive strength of these cement slurries, under the investigated well conditions, reaches, at least, 2600 psi in up to 29 hours. The technological innovation presented in this study, according to the technical framework required by oil company for cement slurry used in primary cementing for producer intervals, proves to be feasible economically, since the introduction of 10% of drilling cuttings into the cement slurry composition provides a cement slurry cost reduction by produced volume, as a result of the cement content and related chemicals decreases, as well as the reduction of over 80% in the drill cuttings processing cost to the oil drilling contractors, due to the lower waste volume destined for controlled landfills. In addition, such an initiative can be considered fair socially because it creates an investment opportunity for the drill cuttings processing by society, through partnerships or cooperatives, enabling the employment and income generation; And sustainable environmentally, by reducing the drill cuttings disposal to the environment, whether by industrial landfill disposal or underground injection. / A indústria de petróleo, em todos os seus segmentos, tem potencial para causar impactos ao meio ambiente. Um dos principais impactos sobre o meio físico, gerado pela indústria de petróleo, está associado à perfuração de poços de petróleo em virtude da geração de diversos resíduos, entre os quais estão os fluidos de perfuração e os cascalhos resultantes da perfuração de poços de petróleo. Estima-se que na região Nordeste do Brasil exista atualmente uma quantidade de resíduos da ordem de 100 mil m³ oriundos do processo de perfuração de poços terrestres para a produção de petróleo e, ainda, em função do crescente número de poços, presume-se uma geração anual de 50 mil m³. Devido à quantidade gerada de cascalhos e seus contaminantes orgânicos e inorgânicos, como também o tratamento, o transporte, o descarte, e os expressivos custos associados, geralmente há contratempo no gerenciamento destes resíduos sólidos, como por exemplo, a adequação do volume de cascalhos produzidos por um período de tempo versus o tempo necessário para a avaliação e liberação de área destinada ao aterro industrial, pelos órgãos de controle e fiscalização do estado, visando o acolhimento e manutenção, em segurança, destes resíduos. O presente estudo tem por objetivo analisar a viabilidade técnica da adição dos resíduos de cascalhos de perfuração (RCP) na pasta de cimento, utilizada em poços de petróleo. As propriedades físico-químicas das pastas de cimento com cascalhos retratadas neste estudo são derivadas de testes laboratoriais efetuados para a adequação das mesmas aos parâmetros técnicos estabelecidos por operadora. Os testes executados em laboratório foram: massa específica, reologia, filtrado, água livre, tempo de espessamento, estabilidade e resistência compressiva da pasta. Alguns resultados relevantes são descritos a seguir, destacando-se o aumento de 8% no rendimento das pastas de cimento com cascalhos examinadas, com relação às pastas de cimento convencionais, para uma dada massa específica. A resistência compressiva destas pastas, nas condições de poço investigadas, atinge, no mínimo, 2600 psi em até 29 horas. A inovação tecnológica apresentada neste estudo, conforme o enquadramento técnico requerido pela operadora para pasta de cimento utilizada em cimentações primárias de intervalos produtores, demonstra ser economicamente viável, uma vez que a introdução de 10% de cascalhos de perfuração na composição de pastas de cimento proporciona uma redução no custo específico da pasta de cimento, em decorrência da redução do teor de cimento e produtos químicos relacionados a este, na pasta produzida, assim como a redução de mais de 80% no custo do beneficiamento dos cascalhos, bem como a diminuição do custo de logística e outros custos correlatos para a operadora, devido a menor volume de resíduos destinados a aterros controlados. Ademais, tal iniciativa pode ser considerada socialmente justa, em virtude de conceber uma oportunidade de investimento para a realização do beneficiamento dos cascalhos pela sociedade, por meio de associações ou cooperativas, viabilizando a geração de emprego e renda; e ambientalmente sustentável, em razão da redução do descarte de cascalhos para o ambiente, quer seja pela disposição em aterros industriais ou injeção no subsolo. / São Cristóvão, SE
115

Sazonalidade, refrigeração e diferentes tipos de recobrimento na conservação pós-colheita de estacas de cordiline (Cordyline rubra Hügel). / Seasonality, refrigeration and different types of coating on the postharvest conservation of Cordyline rubra Hügel cuttings.

Nelson Mamoru Sakamoto 06 June 2005 (has links)
O mercado mundial de floricultura gera um fluxo de quase US$ 7bilhões anuais, atualmente concentrado em países como Holanda, Alemanha, Itália, Colômbia, Costa Rica, Equador, Quênia, Tailândia, Malásia, Israel e EUA. O Brasil ainda contribui pouco, aproximadamente 0,3% do total, sendo a participação brasileira concentrada na exportação de mudas, bulbos, flores e folhagens tropicais. O Brasil possui grande potencial exportador de flores e plantas ornamentais através da organização dos produtores, profissionalização do setor, apoio governamental e desenvolvimento técnico. O emprego de técnicas simples de armazenamento poderia viabilizar o transporte por modais que não o aéreo, reduzindo custos e podendo prolongar a vida útil dos produtos, criando um diferencial de qualidade em relação aos concorrentes. Este trabalho compara cinco diferentes tipos de recobrimento em estacas de Cordyline rubra Hügel (película amilácea, pasta de parafina no ápice, pasta de parafina no ápice e vermiculita umedecida na base, saco plástico ou sem recobrimento), sazonalidade (estacas coletadas durante primavera ou outono), dois ambientes de armazenamento (ambiente refrigerado a 10ºC ou temperatura ambiente 22-32ºC) e diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), a fim de reduzir sua atividade biológica, perda de água e ataque de patógenos. Foi escolhida esta espécie por ser muito apreciada como planta ornamental devido à beleza de suas folhas, e exportada na forma de estacas de diferentes tamanhos. O experimento foi conduzido nas dependências do Departamento de Produção Vegetal da Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, no município de Piracicaba, Estado de São Paulo. Foram utilizadas 615 estacas com 30 cm de comprimento por 3 cm de diâmetro. Um lote testemunha sem armazenamento de 15 estacas foi colocado em leito de enraizamento. Cada tratamento foi composto por 30 estacas pré-tratadas (tipos de recobrimento), submetidas a diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), sendo divididos em 2 sub-tratamentos de 15 estacas (temperatura ambiente ou refrigerada), totalizando 120 estacas. Após o armazenamento foram cortados 3 cm da base de cada estaca, em seguida tratadas com IBA a 10.000 mg/L e colocadas em leito de enraizamento. Após 90 dias foram avaliados os seguintes parâmetros: porcentagem de desenvolvimento, número e massas de matéria fresca e seca de brotos, raízes e rizomas. Observou-se que as estacas colhidas na primavera apresentaram melhor enraizamento e produção de massas secas e frescas. Os menores períodos de armazenamento proporcionam melhor desenvolvimento das estacas, bem como estacas armazenadas em ambiente refrigerado apresentaram melhores resultados do que as mantidas em temperatura ambiente. Os tipos de recobrimento que melhor conservaram as estacas, em ordem decrescente de resultados, foram o saco plástico, parafina no ápice e vermiculita umedecida na base, parafina no ápice, película de amido e sem recobrimento. Conclui-se que o método mais prático foi embalar as estacas em sacos plásticos por não necessitar de fonte de calor para o preparo da película. Quanto maiores os períodos de armazenamento, menores desenvolvimentos de brotos, raízes e rizomas; os melhores resultados foram obtidos com estacas colhidas na primavera e armazenadas em ambiente refrigerado. / The world market of floriculture, generates an annual flow of US$ 7billion, is currently based on countries like The Netherlands, Germany, Italy, Colombia, Costa Rica, Ecuador, Kenya, Thayland, Malaysia, Israel and the USA. The Brazilian contribution to the total world market is approximately 0.3%, where the mains exports are cuttings, bulbs, tropical fresh cut flowers and foliages. Brazil, however, has a great potential to increase its export of flowers and other ornamental plants through the better organization of producers, professionalization of the sector, government support and technical development. The use of simple storage techniques, would enable the transport through other means than airplanes, consequently reducing costs and adding extra shelf life to the product, creating a quality differentiation in relation to competitors. This work was aimed at comparing five types of coating of Cordyline rubra Hügel cuttings (starch film, paraffin paste at the apex, paraffin past at the apex associated with moist vermiculite at the base of the cuttings, plastic bags or no coating), seasonality (cuttings harvested during spring or autumn), two types of enviromental temperatures (refrigeration under 10ºC or environmental temperature between 22-32ºC) and different lengths of time on storage (30, 60, 90 or 120 days), in order to reduce their biologycal activity, water loss and pathogen attacks. This specie is very appreciated as an ornamental plant due to the beauty of their foliage and is exported as cuttings of different sizes. The experiment was carried out at the Departament of Plant Production at “Luiz de Queiroz” College of Agriculture, University of Sao Paulo, in Piracicaba City, Sao Paulo State, Brazil. A total of 615 cuttings were used, each measuring 30 cm by 3 cm diameter. A control group of 15 cuttings without storage was planted on rooting bed. Each treatment was comprised of 30 pre-coated cuttings (types of coating), stored at different periods (30.60, 90 or 120 days) and split into 2 sub-treatments of 15 cuttings, either stored at room temperature or under refrigeration, summing up 120 cuttings. After storage, each cutting had 3 cm excised from its base, prior to being treated with IBA 10.000 mg/L and placed at rooting beds. After 90 days, the following parameters were assessed: percentage of cuttings showing growth and development, number and fresh and dry matter of the shoots, roots and rhizoms. It was observed that cuttings obtained during the spring, showed better rooting and production of biomass. The shorter the storage periods the better the cutting sprouting. Cuttings stored under refrigeration showed better results than kept under room temperature. The types of coatings which best supported the longevity of the cuttings, in decrease order, were: plastic bag, paraffin paste at the apex and moist vermiculite at the base, paraffin on the apex, starch film and no coating. Such results allow to conclude that the most practical coating technique was found to be the use of plastic bags, which did not need heating for the prepare of the film. The longer the storage time the smallest the number of viable cuttings; best results where observed for cuttings harvested during the spring and kept under refrigeration storage.
116

Teores de carboidratos em estacas lenhosas de mirtileiro / Carbohidrates content in hardwood cuttings of blueberry

Oliveira, Rérinton Joabél Pires de 26 February 2010 (has links)
Made available in DSpace on 2014-08-20T13:59:13Z (GMT). No. of bitstreams: 1 dissertacao_rerinton_joabel_oliveira.pdf: 1061872 bytes, checksum: 090acbd80306ffa94125e3268c96951f (MD5) Previous issue date: 2010-02-26 / The aim at this work was to evaluate the alterations on carbohydrates metabolism of hardwood cuttings of blueberries cv. Delite, Powder Blue and Seleção 19. The starch and soluble sugars concentration were evaluated in blueberry branches at four different times in a first experiment (03/06, 04/07, 24/07 and 11/08/2008) and later the metabolism of carbohydrates were evaluated in harvested hardwood cuttings submitted to rooting conditions. It was verified that the cv. Powder Blue has higher starch concentration in the branches than Delite and Seleção 19. Hardwood cuttings of blueberry with low percentage of starch, when subjected to rooting, have resynthesis of starch. At the end of the winter, there is an increase in starch in the branches of woody blueberry. A higher amount of starch in the branches during the winter is associated to a higher rate of rooting. / O objetivo do trabalho foi avaliar as alterações no teor de carboidratos em estacas lenhosas de mirtileiro das cultivares Delite, Powder Blue e Seleção 19. Foram analisados os teores de amido e de açúcares solúveis a partir de ramos coletados em quatro épocas diferentes (03/06, 04/07, 24/07 e 11/08/2008) em um primeiro experimento e, posteriormente, avaliou-se o teor de carboidratos em estacas, coletadas nas mesmas épocas citadas, submetidas a condições de enraizamento. Verificou-se que a cv. Powder Blue possui maior reserva amilácea que a cv. Delite e Seleção 19. Estacas lenhosas de mirtileiro com baixos teores de amido, quando submetidas ao enraizamento, apresentam ressíntese de amido. No fim do período de inverno, ocorre um aumento na concentração de amido nos ramos lenhosos de mirtileiro. Maior teor de amido nos ramos durante o período de inverno está associado à maior taxa de enraizamento.
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Analyse de la diversité de processus de développement racinaire chez les Prunus : aptitude au bouturage et réponses à la contrainte hydrique / Analysis of the diversity of root development process in Prunus : rooting ability of hardwood cuttings and responses to water stress

El Debbagh, Nabil 15 April 2016 (has links)
La sélection des nouveaux porte-greffes du genre Prunus a pour principal objectif d’utiliser lavariabilité génétique existant au sein des différentes espèces de Prunus afin de créer un matérielvégétal innovant, performant au plan agronomique et résistant à différentes contraintes biotiques etabiotiques. L’exploitation de la variabilité génétique s'appuie sur le phénotypage des différentsindividus présents dans les collections de ressources génétiques pour les caractères recherchés. Celapermet de sélectionner des génotypes spécifiques pour améliorer un trait donné.Dans cette étude constituée de deux parties, nous avons exploré la diversité génétique au seindu genre Prunus pour ce qui concerne deux traits importants : l’aptitude au bouturage et les réponsesde certains porte-greffes à la contrainte hydrique.Dans la première partie l’aptitude au bouturage ligneux a été explorée dans une collectiongénétique de 222 génotypes. Les résultats obtenus montrent une variabilité considérable entre les sousgenresAmygdalus et Prunophora et également une variabilité interspécifique au sein de chaque sousgenre.La réussite au bouturage est nettement améliorée chez les hybrides interspécifiques dont un desparents appartient à l’espèce P cerasifera.Dans la deuxième partie nous avons étudié les réponses à la contrainte hydrique chez neufgénotypes couramment utilisés comme porte-greffes. Nous avons comparé trois régimes hydriquesdifférents : témoins, stressés et recouvrés. L’humidité du substrat est maintenue à la capacité au champtout au long de l’expérience pour les plants témoins, par contre l’arrosage a été arrêté pendant 14 jourspour les plants stressés, puis il a été repris pendant 10 jours pour les plants recouvrés. Durant cetteexpérience, nous avons effectué des mesures morphologiques et physiologiques sur la partie aérienneainsi que des excavations à la fin de chaque phase pour examiner les modifications au niveau dusystème racinaire. Sur la partie aérienne, la contrainte hydrique a provoqué une diminutionsignificative de la photosynthèse nette, de la transpiration totale, de la conductance stomatique, et del’expansion des feuilles.Le système racinaire a répondu à cette contrainte par plusieurs modifications. D’abord, le ratio racines/pousses a augmenté pour 4 génotypes (GF305, GF677, Montclar et Myrobolan1254). Ensuite, lesdifférents traits de l’architecture racinaire ont montré des modifications sous l’effet de la contraintehydrique : la longueur de la zone apicale non ramifiée (LZANR) qui traduit l’élongation racinaire,ainsi que les diamètres apicaux des racines ont diminué chez tous les génotypes. Par conséquent lesracines se sont affinées et ont réduit leur croissance en longueur. Produire des racines plus finesaugmente la surface de contact entre les racines et le sol et améliore la capacité d’absorption. Unediminution de la distance inter-ramification a été observée chez les plants stressés. Cette modificationpourrait s’expliquer par le fait que les plantes produisent plus de racines latérales en profondeur oùl’eau est souvent plus disponible. De plus, les racines latérales produites étaient également plus fines.Au plan qualitatif, les génotypes ont eu des réponses semblables, mais l’intensité de la réponse a variéselon les génotypes. / In breeding programs of Prunus rootstocks the aim is to use the existing genetic variabilitywithin Prunus species in order to create new rootstock genotypes with excellent agronomic traits, andimproved resistance to biotic and abiotic stresses.Exploitation of the genetic variability is based on the evaluation of phenotypic variation amongindividuals within genetic collections for desirable traits. This make possible to select specificgenotypes to improve a given trait.This study consists of two parts; we explored the genetic diversity within the genus Prunusregarding two important characteristics: rooting ability of hardwood cuttings and responses of somerootstocks to water stress.In the first part, rooting ability of hardwood cuttings was evaluated among 222 genotypespreserved in genetic collection. The results show considerable variability among the sub genusAmygdalus, Prunophora, and also an interspecific variability within each of them. Rooting ability byhardwood cutting was significantly improved in interspecific hybrids if one parent belongs to Pcerasifera species.In the second part of this study we studied the responses of nine genotypes, commonly usedrootstocks, to water stress. We applied three treatments: control, water stress and recovering.Soil moisture was maintained at field capacity through all stages of the experiment for the controlplants. On the contrary we stopped watering during 14 days for the stressed plants, and then we rewateredthe recovered plants for 10 days.During this experience, we performed morphological and physiological measurements on the aboveground parts of plants and we excavated plants at the end of each phase to observe root systemmodifications.Aboveground parts of plant responded to water stress by a significant decrease in net photosynthesis,total transpiration, stomatal conductance and leaf expansion.Root system responded to water stress by several modifications:Four genotypes (GF305, Montclar, GF677 and Myrobolan) showed a significant increase in root toshoot ratio under drought conditions. We also detected morphological modifications on the differenttraits of root architecture in response to water stress.The length of the apical unbranched zone LAUZ and the apical diameter were decreased forall genotypes, consequently, roots became finer and reduced their rate of elongation. Fine rootsenhance the surface of contact between roots and soil which in turn improve the acquisition of waterunder drought condition.The inter-branch distance also responded, and it tended to decrease under the water stress treatment.The decrease in inter-branch distance can be explained by a production of more lateral roots in deeplayers, where water was more available, moreover these new laterals roots were also finer.Qualitatively, a common response to water stress was observed on the different traits of the rootsystem architecture, but we showed a genotypic effect determining the level of the response.
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La provenance des boutures influence-t-elle le rendement et les taux de phytoextraction des saules dans un sol contaminé?

Beauchamp, Sonia 03 1900 (has links)
La survie et la croissance des plantes sont essentielles afin d’assurer l’efficacité des protocoles de phytoremédiation et la décontamination des friches contaminées. La survie des saules et leur adaptation aux contaminants dépendent de la nature et de la concentration des contaminants. L’objectif de l’étude est d’identifier les cultivars ayant les meilleurs rendements, mais aussi de déterminer si la provenance des boutures (milieu contaminé ou milieu non contaminé) pourrait influencer la survie, la croissance et la phytoextraction (Cd, Cr, Cu, Ni, Pb, Zn) des saules. Nous avons comparé ces différents paramètres pour des boutures de dix cultivars de saules dans un milieu industriel fortement contaminé par les composés organiques et dans un milieu non-contaminé. Les variations dans la réponse des cultivars selon la provenance des boutures (milieu contaminé ou milieu non-contaminé) ont aussi été analysées dans chacun des sites d’étude. Selon nos résultats, le cultivar ˈ5005ˈ (Salix alba) est très productif en milieu extrêmement contaminé. Le cultivar ˈS25ˈ (Salix eriocephala) est aussi un choix très intéressant en phytoremédiation, puisqu’il produit près de deux fois plus de biomasse racinaire comparativement aux autres cultivars. La provenance des boutures n’a pas d’impact significatif sur la survie, la croissance et la phytoextraction pour la majorité des cultivars sauf pour le cultivar ‘Millbrook’, où les individus provenant du milieu contaminé ont produit significativement plus de biomasse aérienne lorsqu’ils poussaient en sol contaminé comparativement aux individus qui n’ont jamais été en contact avec les contaminants. Ces résultats pourraient aider à planifier des protocoles de phytoremédiation plus efficaces, en sélectionnant les cultivars de saule les plus adéquats et en élaborant l’échantillonnage des boutures utilisées dans les sites appropriés. / Plant survival and growth are essential parameters to monitor the effectiveness of phytoremediation protocols and the eventual decontamination of brownfields. The ability of different willow cultivars to survive and adapt to contaminants in polluted soils depends on the nature and concentration of the contaminants. The objective of the study was to identify the cultivars with the highest yields, but also to determine whether the origin of the cuttings (contaminated site or not) might influence survival, growth and phytoextraction of willow cultivars. We compared survival, growth and phytoextraction (Cd, Cr, Cu, Ni, Pb, Zn) of cuttings of ten willow cultivars in a highly organic-contaminated industrial environment and in an uncontaminated soil. Variations in the response of the cultivars according to the origin of the cuttings were also analyzed for each sites. According to our results, cultivar ˈ5005ˈ (Salix alba) was very productive in an extremely contaminated environment. Cultivar ˈS25ˈ (Salix eriocephala) was also a relevant choice, as it produced nearly twice more root biomass compare to other cultivars. The origin of the cuttings did not have significant influence on survival, growth and phytoextraction for almost all cultivar except the ˈMillbrookˈ cultivar: individuals originating from the contaminated environment produced significantly more aboveground biomass when growing in the contaminated environment compared to individuals who had never been in contact with contaminants. These results could help build more effective phytoremediation protocols in highly contaminated environments by selecting adequate willow cultivars and sampling cuttings in an appropriate environment.
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Influence de la température sur la phénologie de la canne à sucre : conséquences sur la phase d'implantation de la culture dans les Hauts de La Réunion / Influence of temperature on surgarcane phenology : effects on the implementation phase of crops in the highlands of Reunion Island (les Hauts)

Poser, Christophe 05 September 2013 (has links)
Cette étude s'intéresse aux effets de la température sur le développement de la canne à sucre et le potentiel d'expansion de cette culture au sein de nouvelles zones géographiques. En particulier, elle vise à caractériser les stades de développement de la plante durant lesquels les basses températures agissent afin d'extrapoler des zones géographiques d'adaptation. Un travail plus particulier est engagé sur l'effet des basses températures en condition d'altitude tropicales dans Les Hauts de La Réunion. L'implantation en cycle de plantation est identifiée comme une étape très importante pour les cultures de canne, et pour la culture dans les Hauts en particulier, car elle conditionne non seulement la date de première récolte et son niveau mais elle a un impact sur le cycle de repousse. Les expérimentations ont lieu à la fois en milieu contrôlé (chambre climatique et serre) et en conditions réelles (champs à différentes altitudes). Une étude méthodologique sur la qualité du matériel végétal est réalisée pour valider les conditions d'expérimentation. Cette étude montre que des expérimentations de débourrement de bourgeons peuvent être réalisées avec des boutures d'un seul bourgeon, de taille réduite. Les comparaisons de débourrement à différentes températures nécessitent d'utiliser des boutures triées, saines, et homogènes, c'est-à-dire provenant de la partie médiane de la tige-mère. Les bourgeons de la partie supérieure (entrenœuds non consolidés à croissance non terminée) et ceux issus de la base de la plante devront être écartés. L'influence de la température est quantifiée sur différentes variétés lors de la phase de débourrement-levée, puis au cours des stades de développement suivants jusqu'à la fermeture du couvert végétal. La température influence considérablement sur le processus de débourrement. Le modèle thermique élaboré, bien que limité à une gamme de températures, prédit de façon satisfaisante la levée à température constante et permet de quantifier les différences variétales observées. Les expérimentations au champ révèlent des différences dans les dynamiques d'émission et de croissance des tiges et de mise en place de la surface foliaire, non seulement entre sites d'altitude différente mais aussi entre variétés. La température joue un rôle majeur dans cette différenciation. De plus, selon le processus étudié, le classement des variétés suivant leurs performances n'est pas strictement identique d'un site à l'autre. Ce constat révèle l'intérêt d'approfondir l'étude sur la période d'installation du feuillage en conditions climatiques variées. Le modèle de débourrement-levée développé au cours de cette étude a permis d'identifier des indicateurs pour évaluer la capacité d'adaptation de différentes variétés de canne à sucre. Associés à une base de données météorologique géolocalisée, ces derniers mettent en évidence l'importance de la température seuil dans la capacité d'adaptation des variétés à différentes zones géographiques. Les méthodes et outils élaborés au cours de cette thèse ont d'ores et déjà des retombées pour accompagner les outils traditionnels de sélection variétale à La Réunion et sont extrapolables dans des zones à températures plus fraîches. Ces retombées pourraient s'accroître avec la mise au point de nouveaux itinéraires techniques. Enfin, la poursuite des travaux cartographiques, comme outils d'étude du potentiel d'implantation des cultures dans les Hauts, constitue également un axe prometteur pour la valorisation des acquis de cette thèse. / This thesis is centered on the effects of temperature on sugarcane development and its potential for geographical expansion under low temperatures in high-altitude tropical conditions. In the highlands of Reunion Island (les Hauts), the duration of the germination, in planting years, affects the date and the level of the first harvest, as well as the sugarcane yield in the following ratoon crop cycle. Trials took place in climate chambers, greenhouses and fields at different temperatures and altitudes. A preliminary study validates the conditions governing the experimentation: bud bursts can be studied through single, healthy, single bud cuttings that are taken from the middle section of the mature stem. Temperature considerably influences the primary tiller germination and emergence stages. The thermal model that was developed satisfactorily predicts bursting at a constant temperature and allows for the quantification of observed varietal differences. Field trials reveal a disparity in the production and growth dynamics of leaves and stems according to locations and varieties. Temperature influences this differentiation. Among the indicators that were elaborated, the duration for the seedling of half the population, when applied to a climatic database, allows one to define geographical zones and time periods conducive to the introduction of sugarcane according to its variety. The methods presented herein can be used in varietal selection for all zones where cold temperature limits the spread of crops. Results could be used for the development of new cultural practices or for further studies in geo-referenced agronomic zoning.
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Range Searching Data Structures with Cache Locality

Hamilton, Christopher 17 March 2011 (has links)
This thesis focuses on range searching data structures, an elementary problem in computational geometry with research spanning decades. These problems often involve very large data sets. Processor speeds increase faster than memory speeds, thus the gap between the rate at which CPUs can process data and the rate at which it can be retrieved is increasing. To bridge this gap, various levels of cache are used. Since cache misses are costly, algorithms should be cache-friendly. The input-output (I/O) model was the first model for constructing cache-efficient algorithms, focusing on a two-level memory hierarchy. Algorithms for this model require manual tuning to determine optimal values for hardware dependent parameters, and are only optimal at a single level of a memory hierarchy. Cache-oblivious (CO) algorithms are built without knowledge of the hierarchy, allowing them to be optimal across all levels at once. There exist strong theoretical and practical results for I/O-efficient range searching. Recently, the CO model has received attention, but range searching remains poorly understood. This thesis explores data structures for CO range counting and reporting. It presents the first space and worst-case query-time optimal approximate range counting structure for a family of related problems, and associated O(N log N)-space query-optimal reporting structures. The approximate counting structure is the first of its kind in internal memory, I/O and CO models. Researchers have been trying to create linear-space query-optimal CO reporting structures. This thesis shows that for a variety of problems, linear space is in fact impossible. Heuristics are also used for building cache-friendly algorithms. Space-filling curves are continuous functions mapping multi-dimensional sets into one-dimensional ones. They are used to build search structures in the hopes that objects that were close in the original space remain close in the resulting ordering. This results in queries incurring fewer page swaps when traversing the structure. The Hilbert curve is notably good at this, but often imposes a space or time penalty. This thesis introduces compact Hilbert indices, which remove the ineffiency inherent for input point sets with bounding boxes smaller than their bounding hypercubes.

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