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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.
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Inoculação via semente e foliar de Azospirillum brasilense associado ao tratamento de sementes com bioativador na cultura do milho / Seed and leaf inoculation with Azospirillum brasilense associated with bioactivator seed treatment in maize

Battistus, Andre Gustavo 24 February 2015 (has links)
Made available in DSpace on 2017-07-10T17:36:59Z (GMT). No. of bitstreams: 1 Andre_Gustavo_Battistus.pdf: 1616847 bytes, checksum: 70a506c626b68378edefb97e8b5fdfe4 (MD5) Previous issue date: 2015-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The maize is a cereal with high economic importance due to its magnitude forms of use. Increasing productivity levels, promoting substances plant development are highlighted role in contemporary agriculture, arising from biological or chemical origin. However, the lack of results regarding the joint use of these promoters leads to the need for information on their simultaneous use. In this context, this work aimed to evaluate the effects of joint use of thiamethoxam combined with seed inoculation and foliar spray Azospirillum brasilense on physiological quality of corn seeds and its agronomic performance in two environments in the growing field. Initially, we tested bacterial growth in culture medium containing increasing concentrations of thiamethoxam. It was also evaluated the initial development and physiological quality of seedlings by morphometric measurements, emergency speed index and SPAD index through factorial 2 x 3 with seed inoculation with A. brasilense (100 mL per 25 kg seeds) thiamethoxam and three doses (0, 28 and 42 mg per 60,000 seeds). In the field, factorial 2 x 4 was composed by the presence and absence of chemical seed treatment with bioactivator of thiamethoxam plants (28 mg per 60,000 seeds), while the second factor comprised seeds without inoculation; seed inoculation with A. brasilense (100 mL per 60,000 seeds), foliar spray inoculant base A. brasilense (300 mL ha-1) and associated with the seed inoculated with A. brasilense foliar spray, tested in high ambient and applying average production technology. The treatments were evaluated by morphometric analysis, nutrient content in plant tissues, components production and crop yield. The bacterial population showed a linear decrease with increasing doses of thiamethoxam. The dose of 42 mg of thiamethoxam caused reduction in emergence speed, SPAD index, shoot length and root, root volume, root/shoot and dry matter of shoots, while inoculation showed activity positive physiological quality of seedlings. Thus, combined with inoculation dose of 28 mg thiamethoxam demonstrates synergistic effect in the early development of maize seedlings. In the field, thiamethoxam, as well as seed inoculation + foliar spray promote increase in plant length, stem diameter, leaf and mass accumulation area throughout the plant cycle in both environments. Reduction in moisture content, impurities and discounts of grain mass, as well as increases in leaf phosphorus levels are the result of inoculation, yet without deterioration in corn yields. Thiamethoxam also reduced the moisture of the grain mass. Productivity was increased by the presence of thiamethoxam on average productive technology environment / O milho é um cereal de elevada importância econômica devido à sua magnitude de formas de utilização. Incrementando os níveis de produtividade, substâncias promotoras de desenvolvimento vegetal ganham papel de destaque na agricultura contemporânea, advindas de origem biológica ou química. Contudo, a escassez de resultados a respeito da utilização conjunta desses promotores leva à necessidade de informações sobre sua utilização simultânea. Neste contexto, esta obra buscou avaliar os efeitos da utilização conjunta de tiametoxam aliado à inoculação via semente e pulverização foliar de Azospirillum brasilense na qualidade fisiológica de sementes de milho e seu desempenho agronômico em dois ambientes de investimento em cultivo a campo. Inicialmente, testou-se o crescimento bacteriano em meio de cultura contendo concentrações crescentes de tiametoxam. Avaliou-se também o desenvolvimento inicial e qualidade fisiológica de plântulas por medidas morfométricas, índice de velocidade de emergência e índice SPAD, por meio de arranjo fatorial 2 x 3, com inoculação de sementes com A. brasilense (100 mL por cada 25 kg de sementes) e três doses de tiametoxam (0, 28 e 42 mg por 60.000 sementes). À campo, esquema fatorial 2 x 4 foi composto pela presença e ausência de tratamento químico de sementes com o bioativador de plantas tiametoxam (28 mg por 60.000 sementes), enquanto o segundo fator englobou sementes sem inoculação; inoculação de sementes com A. brasilense (100 mL por 60.000 sementes), pulverização foliar de inoculante a base de A. brasilense (300 mL ha-1) e inoculação de sementes associado à pulverização foliar com A. brasilense, testados em ambientes de alta e média aplicação de tecnologia de produção. Os tratamentos foram avaliados por análises morfométricas, teor de nutrientes nos tecidos vegetais, componentes da produção e produtividade da cultura. A população bacteriana mostrou redução linear de acordo com o aumento das doses de tiametoxam. A dose de 42 mg de tiametoxam causou redução na velocidade de emergência, índice SPAD, comprimento de parte aérea e de raiz, volume de raiz, relação raiz/parte aérea e massa da matéria seca de parte aérea, enquanto que, a inoculação evidenciou atividade positiva na qualidade fisiológica das plântulas. Deste modo, a inoculação combinada com dose de 28 mg de tiametoxam demonstra efeito sinérgico no início do desenvolvimento de plântulas de milho. À campo, o tiametoxam, assim como a inoculação via semente + pulverização foliar, promoveram incrementos no comprimento das plantas, diâmetro de colmo, acúmulo de massa e área foliar ao longo do ciclo vegetal em ambos os ambientes. Redução no teor de umidade, impurezas e descontos da massa de grãos, assim como incrementos nos níveis foliares de fósforo são resultados da inoculação, contudo sem apresentar alterações na produtividade do milho. Tiametoxam também reduziu a umidade da massa de grãos. A produtividade foi incrementada pela presença do tiametoxam em ambiente de média tecnologia produtiva
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Auxinas e tipos de estacas no enraizamento de Camellia sinensis / Auxins and types of cuttings on rootings of Camellia sinensis

Dall'Orto, Luigi Tancredi Campo 26 August 2011 (has links)
Com o objetivo de avaliar a influência de cultivares, tipos de estacas de Camellia sinensis e doses de ácido indolbutírico no enraizamento de estacas, dois experimentos foram conduzidos em casa de vegetação, no delineamento experimental em blocos ao acaso com 16 tratamentos, no esquema fatorial 2 x 2 x 4, ou seja, tipos de estaca (herbácea e lenhosa), cultivares (Camellia sinensis IAC 259 e Yabukita) e quatro doses de ácido indolbutírico (AIB) (0, 30, 60 e 90 mg L-1), com quatro repetições. Cada repetição foi composta por 20 estacas da porção mediana dos ramos das plantas matrizes, coletadas em duas épocas do ano (verão e inverno). As estacas foram cortadas em bisel e mantidas com uma gema e uma folha inteira, com 5 a 7 cm de comprimento. A região basal das estacas recebeu ou não tratamento com ácido indolbutírico (AIB), através da imersão de 2,5 cm da base em solução aquosa do produto por 24 horas. Posteriormente, elas foram colocadas em bandejas de isopor de 72 células contendo vermiculita de grânulos médios. As estacas herbáceas apresentaram maior porcentagem de enraizamento com a aplicação de AIB comparada às estacas lenhosas, sendo que as estacas coletadas no período do verão apresentaram maior porcentagem de enraizamento em menor espaço de tempo, quando comparadas com as estacas coletadas no período do inverno. Estacas da cultivar Yabukita apresentaram maior potencial de enraizamento em relação às estacas da cultivar IAC 259. As concentrações recomendadas de AIB para o enraizamento de estacas de Camellia sinensis variaram de 56 a 83 mg L-1 em função da cultivar. / Aiming to evaluate the influence of Camellia sinensis cultivars, types of cuttings and doses of IBA on rooting, two experiments have been conducted in a green house in the experimental design in blocks randomized with 16 treatments, arranged in a 2 x 2 x 4, that is, cutting types (herbaceous and woody), cultivars (Camellia sinensis \'IAC 259\' and \'Yabukita\') and four doses of butyric acid (IBA) (0, 30, 60 and 90 mg L -1) with four replications. Each replication consisted of 20 cuttings from the middle portion of the branches from the mother plants, collected in two seasons (summer and winter). The cuttings were cut in bevel and maintained with a bud and a leaf, with 5-7 cm long. The basal cuttings have received or not treatment with indol butyric acid (IBA) by immersion of 2.5 cm from the base in an aqueous solution of the product for 24 hours. Later, they have been placed in trays with 72 cells containing medium granules of vermiculite. Herbaceous cuttings have presented higher percentages of rooting with IBA application compared to hardwood cuttings, and cuttings collected in summer have showed the highest percentage of rooting in the shortest time compared with the cuttings collected in winter. Yabukita cultivars cuttings had higher rooting potential in relation to the IAC 259 cuttings. IBA level to the rooting of Camellia sinensis varied from 56 to 83 mg L-1 according to cultivars
23

Synthèse et évaluations biologiques de strigolactones, nouvelle classe d'hormones végétales / Synthesis and biological evaluations of strigotactones, a new class of plant hormones

Chen, Victor 20 July 2011 (has links)
Ce travail de thèse présente la mise au point d’une nouvelle stratégie de synthèse en vue de l’obtention d’analogues des strigolactones, apocaroténoïdes possédant de multiples activités biologiques d’intérêt agronomique : médiateurs chimiques intervenant dans la mise en place de la symbiose endomycorhizienne et nouvelle classe d’hormone végétale contrôlant l’architecture de la plante.La stratégie de synthèse est basée sur l’utilisation d’une séquence de deux réactions clefs qui sont une métathèse cyclisante d’oléfine (RCM) et une cyclisation radicalaire avec transfert d’atome catalysée par un métal de transition (ATRC). Tout d’abord, une synthèse rapide et efficace des précurseurs a été développée et après optimisation de la séquence RCM / ATRC, divers analogues fonctionnalisés en position C4 ont été obtenus après aménagements fonctionnels. D’autres bioisostères des strigolactones naturelles ont été synthétisés par variation au niveau du cycle C. En se basant sur la voie synthétique précédemment élaborée, la première synthèse asymétrique du Solanacol a été effectuée permettant la détermination de sa stéréochimie relative en C2’ et sa configuration absolue. L’évaluation des activités biologiques dans les différents modèles des composés synthétisés est aussi décrite. / This Ph.D. work has been centred on the elaboration of a new synthetic strategy in goal to obtain analogues of natural strigolactones, apocarotenoids with various biological activities of agronomic interests: chemical mediators implicated in the endomycorrhizal symbiosis and a new class of plant hormone controlling the plant architecture.The synthetic strategy is based on the sequence of two key reactions, which are ring closing metathesis (RCM) and atom transfer radical cyclisation (ATRC). First, a rapid and efficient access to the synthetic precursors has been developed and after optimisation of the RCM / ATRC sequence, several analogues functionnalised at the C4 position were obtained after judicious steps. Other bioisoters were obtained with variations on the C ring. On the basis of the elaborated synthetic pathway, the first asymmetric synthesis of Solanacol was successfully achieved conducting to the determination of the relative stereochemistry at C2’ position and its absolute configuration. The biological evaluations of the synthesized molecules in the different models were also described.
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Développement technologique et bioproduction d’actifs pour la cosmétique à l'aide de cultures cellulaires végétales indifférenciées / Plant cell culture technology development and bioproduction for cosmetic

Guyon, Jean-Baptiste 17 December 2014 (has links)
Les premières cultures cellulaires végétales in vitro ont été développées à partir de carotte, grâce à Gautheret en 1939. Il a obtenu ce résultat par la découverte au préalable du pouvoir de totipotence des cellules végétales (Haberland 1902). Afin d’obtenir les cellules indifférenciées Gautheret a utilisé des milieux de culture contenant des macroéléments (K, N et P), des microélements (Mg, B,…), des vitamines, du sucre et des phytohormones. Dans la littérature, plusieurs compositions sont souvent utilisées comme White (1934), Murashige and Skoog (1962)) ou Gamborg, Miller et Ojima (1970). Les nuances entre ces milieux se basent sur des concentrations modifiées en phosphates, nitrates ou en phytohormones (auxine/cytokinine). Chaque espèce a besoin d’un milieu particulier pour induire la callogénèse. En effet, selon l’origine (géographique) et le type d’explant (feuilles, racines, tiges,…) traité les conditions d’induction de la callogénèse varieront. De nombreuses personnes portent un intérêt aux cultures cellulaires pour leur utilisation en cosmétique ou en pharmacie. Actuellement, deux entreprises produisent ces cellules à l’échelle industrielle. Ainsi, Phyton Biotech (entreprise allemande) purifie du taxol à partir d’If (Taxus baccata) et Mitsui petrochemical produit de la skinonine à partir de grémils (Lithospernum erythrorizon). / The first plant cell culture has been developed by Gautheret in 1939 based on carrot plant cell tissus. He obtained these results through the discovery of the plant totipotency power (Haberland, 1902). He used for cal production a culture medium composed by macroelements (K, N, P…) and microelements (Mg, B …), vitamin, sugar. Later on, several mediums were used like and described in literature i.e. Murashige and Skoog (1962), White (1934) or Gamborg, Miller and Ojima (1970). The differences between such medium consisted mainly concentrations especially of phosphates, nitrates or auxin/cytokinine balance. However, each species needs specific medium for growth. Any people works of this subject and the interest for pharmaceutical and cosmetical industry grow up. Plant cell culture is a difficult technology an industrial use. Recently, two companies performed industrial production of taxol (Taxus baccata) and shikonin (Lithospernum erythrorizon) respectively PhytonBitotech and Mitsui petrochemical. My thesis work was to develop plant cell cultures fom unusual plants which can be used for the industrial production of cosmetics.

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