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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.
11

Ecophysiology and alecrim pimenta productivity at conditions of Massif BaturitÃ, CearÃ. / Ecofisiologia e produtividade de alecrim pimenta nas condiÃÃes edafoclimÃticas do MaciÃo de BaturitÃ, CearÃ

Maria da SaÃde de Sousa Ribeiro 20 February 2015 (has links)
The medicinal plants are included within the wide diversity of the MaciÃo de Baturità ecosytem and they are an important component of traditional medicine of this region. However, scientific information that may contribute to the increase in the cultivation of these plants are still rare, particularly at conditions of the State of CearÃ. The overall objective of this project is to evaluate the development and the production of alecrim pimenta (Lippia origanoides) at conditions of MaciÃo de BaturitÃ, CearÃ. Two experiments were conducted, the first during the dry season of 2013 (August to November) and the second during the rainy season of 2014 (February to May). The experiment was corned out in completely randomized design with split plots, being the plots defined by two seasons (drought and rainy), the subplot formed by light conditions (greenhouse and full sun), and the subsubplots formed by four evaluation times (0, 40, 80 and 120 days after transplanting). Five replications were used, each one represented by a pot of 20 L containing a plant. The following variables were evaluated: leaf area, plant height, stem diameter, dry matter production, leaf gas exchange, chlorophyll content, mineral nutrients, organic solutes, and essential oils. The alecrim pimenta grows well in the Baturità region, with yields of biomass and essential oil similar to those observed in other studies. The cultivation in greenhouse (50% of solar radiation) changed the pattern of development of alecrim pimenta, resulting in plants with better overall appearance, taller, with larger leaves, higher specific leaf area, less developed root system, and lower root/shoot ratio, regardless of the season of cultivation. The production of dry biomass of leaves and total did not differ between the two environments (light conditions) after 120 days cultivation, regardless of the period of year. During the drought season there was a strong influence of the light condition on stomatal conductance and transpiration, with the values being lower in full sun environment, suggesting stomatal sensitivity to climate conditions in this species. Plants grown in greenhouse showed, in general, higher levels of nutrients and nitrogen compounds (N-aminossolÃveis), compared to plants under full sunlight, regardless of the cropping season. / Dentre os vegetais que compÃem ampla diversidade do MaciÃo de Baturità se inserem as plantas medicinais, sendo estas, principais componentes da medicina tradicional. No entanto, informaÃÃes cientÃficas que possam contribuir para o incremento do cultivo dessas plantas ainda sÃo raras, particularmente nas condiÃÃes edafoclimÃticas do Estado do CearÃ. Objetivou-se com o presente trabalho, avaliar o desenvolvimento e o potencial produtivo do alecrim pimenta (Lippia origanoides) nas condiÃÃes edafoclimÃticas do MaciÃo de BaturitÃ, CearÃ. Foram realizados dois experimentos, sendo o primeiro durante o perÃodo seco de 2013 (agosto a novembro) e o segundo durante o perÃodo chuvoso de 2014 (fevereiro a maio). O experimento foi conduzido seguindo um delineamento inteiramente casualizados com parcelas subsubdivididas, sendo as parcelas definidas pelas duas estaÃÃes (seca e chuvosa), as subparcelas formadas pelas condiÃÃes de luminosidade (telado e pleno sol), e as subsubparcelas pelas quatro Ãpocas de avaliaÃÃo (0, 40, 80 e 120 dias apÃs o transplantio). Foram utilizadas cinco repetiÃÃes, sendo cada repetiÃÃo representada por um vaso de 20 litros contendo uma planta. Foram avaliadas as seguintes variÃveis: Ãrea foliar, altura da planta, diÃmetro do caule, massa seca dos diferentes ÃrgÃos vegetais, trocas gasosas, teores de clorofila, teores de minerais, solutos orgÃnicos e rendimento do Ãleo essencial. O alecrim pimenta desenvolveu-se bem na regiÃo do MaciÃo de BaturitÃ, com produtividades de biomassa e de Ãleo essencial similares Ãs observadas em outros estudos. O cultivo em telado alterou o padrÃo de desenvolvimento do alecrim pimenta, resultando em plantas com melhor aparÃncia geral, mais altas, com folhas maiores, maior Ãrea foliar especÃfica, menor desenvolvimento do sistema radicular e menor relaÃÃo raiz/parte aÃrea, independentemente da Ãpoca de cultivo. A produÃÃo de massa seca de folhas e total nÃo diferiu entre os dois ambientes apÃs 120 dias de cultivo, independentemente do perÃodo do ano. Houve forte influÃncia do ambiente de cultivo no perÃodo seco, sobre a condutÃncia estomÃtica e a transpiraÃÃo, com os valores sendo menores no ambiente a pleno sol, sugerindo a sensibilidade estomÃtica da espÃcie Ãs condiÃÃes atmosfÃricas do perÃodo. As plantas cultivadas em telado apresentaram, de forma geral, maiores teores de nutrientes minerais e de compostos nitrogenados (N-aminossolÃveis), em comparaÃÃo Ãs plantas submetidas a pleno sol, independente do Ãpoca de cultivo.
12

Plasticidade fenotípica em Glycine max e Brachiaria brizantha sob diferentes regimes de temperatura / Phenotypic plasticity in Glycine Max and Brachiaria brizantha under different temperature regimes

Vítolo, Hilton Fabrício 28 March 2011 (has links)
Made available in DSpace on 2016-01-26T18:56:23Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 397972 bytes, checksum: 421297a6aa9990008619c690588f8576 (MD5) Previous issue date: 2011-03-28 / The environmental in which plants are subjected, and the resources necessary for its survival offers a series of restrictions on development imposed by variations in biotic and abiotic factors, mainly temperature. However, responses to environmental changes in agricultural production are variable between different crop species, especially with regard to differences between plants of C3 and C4 metabolism. The aim of this study was to compare the physiological responses of two tropical crop species with C3 and C4 photosynthetic metabolism grown in different temperature regimes, and verify their capacity for acclimatization. The species studied were: Glycine max (L.)Merr, cv. Codetec 202 (Fabaceae) of the cycle C3 and Brachiaria brizantha, cv. Marandú (Poaceae) of the C4 cycle. The plants were treated in a chamber type phytotron (Eletrolab, model EL 011) at temperature (day/night) of 20/15, 30/20 and 40/20°C. Measurements of the photosynthetic variables were extracted from curves A/Ci, curves A/PPFD, chlorophyll fluorescence, and growth variables. Data were subjected to analysis of variance (ANOVA, p<0.05) and means compared by Tukey test (p<0.05) and calculating the index of phenotypic plasticity (IPP). The results showed that under low temperature biomass losses were higher than under high temperature in both species, the same occurred in relation to membrane damage. On the other hand, the photosynthectic capacity of C3 species was more stable at different temperatures, whereas C4 species showed a significant increase at 40°C and a significant reduction at 20°C. In conclusion, the set of results indicated that low temperature caused greater damage to both species, particularly in the C4 species. Moreover, both species showed a greater capacity for acclimation to high temperature. In general, the C4 species showed a phenotypic plasticity comparable to the C3 species. / O ambiente em que as plantas estão imersas, além dos recursos necessários para sua sobrevivência, oferece uma série de restrições ao seu desenvolvimento imposta por variações de fatores bióticos e abióticos, principalmente a temperatura. Todavia, as respostas às alterações do ambiente de produção agrícola são variáveis entre as diferentes espécies cultivadas, especialmente no que se refere às diferenças entre plantas de metabolismo C3 e C4. O objetivo deste trabalho foi comparar as respostas fisiológicas de duas espécies cultivadas tropicais de metabolismo fotossintético C3 e C4 crescidas em diferentes regimes de temperatura e, verificar suas respectivas capacidades de aclimatação. As espécies avaliadas foram: Glycine max (L.) Merr. cv. Codetec 202 (Fabaceae) do ciclo C3 e Brachiaria brizantha cv. Marandú (Poaceae) do ciclo C4. As plantas foram submetidas em câmara climatizada tipo Fitotron (Eletrolab, modelo EL 011) sob temperatura (diurna/noturna) de 20/15, 30/20 e 40/20ºC. As medidas das variáveis da rede fotossintética foram extraídas de Curvas A/Ci, Curvas A/DFFF, Fluorescência da clorofila a, além de variáveis de crescimento. Os dados foram submetidos à análise de variância (ANOVA, p < 0,05) e as médias comparadas pelo teste de Tukey (p < 0,05), além dos cálculos de índice de plasticidade fenotípica (IPF). Os resultados mostraram que sob temperatura baixa as perdas de biomassa foram maiores que sob temperatura alta em ambas as espécies, o mesmo ocorreu em relação aos danos nas membranas. Por outro lado, a capacidade fotossintética da espécie C3 foi mais estável nas diferentes temperaturas testadas, enquanto que a espécie C4 apresentou um aumento significativo a 40ºC e uma redução significativa a 20ºC. Concluindo, o conjunto de resultados indicou que a temperatura baixa causou maiores danos a ambas as espécies, particularmente na espécie C4. Por outro lado, ambas as espécies mostraram maior capacidade de aclimatação a temperatura elevada. De forma geral, a espécie C4 apresentou uma plasticidade fenotípica comparável a espécie C3.
13

Plasticidade fenotípica em Glycine max e Brachiaria brizantha sob diferentes regimes de temperatura / Phenotypic plasticity in Glycine Max and Brachiaria brizantha under different temperature regimes

Vítolo, Hilton Fabrício 28 March 2011 (has links)
Made available in DSpace on 2016-07-18T17:51:07Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 397972 bytes, checksum: 421297a6aa9990008619c690588f8576 (MD5) Previous issue date: 2011-03-28 / The environmental in which plants are subjected, and the resources necessary for its survival offers a series of restrictions on development imposed by variations in biotic and abiotic factors, mainly temperature. However, responses to environmental changes in agricultural production are variable between different crop species, especially with regard to differences between plants of C3 and C4 metabolism. The aim of this study was to compare the physiological responses of two tropical crop species with C3 and C4 photosynthetic metabolism grown in different temperature regimes, and verify their capacity for acclimatization. The species studied were: Glycine max (L.)Merr, cv. Codetec 202 (Fabaceae) of the cycle C3 and Brachiaria brizantha, cv. Marandú (Poaceae) of the C4 cycle. The plants were treated in a chamber type phytotron (Eletrolab, model EL 011) at temperature (day/night) of 20/15, 30/20 and 40/20°C. Measurements of the photosynthetic variables were extracted from curves A/Ci, curves A/PPFD, chlorophyll fluorescence, and growth variables. Data were subjected to analysis of variance (ANOVA, p<0.05) and means compared by Tukey test (p<0.05) and calculating the index of phenotypic plasticity (IPP). The results showed that under low temperature biomass losses were higher than under high temperature in both species, the same occurred in relation to membrane damage. On the other hand, the photosynthectic capacity of C3 species was more stable at different temperatures, whereas C4 species showed a significant increase at 40°C and a significant reduction at 20°C. In conclusion, the set of results indicated that low temperature caused greater damage to both species, particularly in the C4 species. Moreover, both species showed a greater capacity for acclimation to high temperature. In general, the C4 species showed a phenotypic plasticity comparable to the C3 species. / O ambiente em que as plantas estão imersas, além dos recursos necessários para sua sobrevivência, oferece uma série de restrições ao seu desenvolvimento imposta por variações de fatores bióticos e abióticos, principalmente a temperatura. Todavia, as respostas às alterações do ambiente de produção agrícola são variáveis entre as diferentes espécies cultivadas, especialmente no que se refere às diferenças entre plantas de metabolismo C3 e C4. O objetivo deste trabalho foi comparar as respostas fisiológicas de duas espécies cultivadas tropicais de metabolismo fotossintético C3 e C4 crescidas em diferentes regimes de temperatura e, verificar suas respectivas capacidades de aclimatação. As espécies avaliadas foram: Glycine max (L.) Merr. cv. Codetec 202 (Fabaceae) do ciclo C3 e Brachiaria brizantha cv. Marandú (Poaceae) do ciclo C4. As plantas foram submetidas em câmara climatizada tipo Fitotron (Eletrolab, modelo EL 011) sob temperatura (diurna/noturna) de 20/15, 30/20 e 40/20ºC. As medidas das variáveis da rede fotossintética foram extraídas de Curvas A/Ci, Curvas A/DFFF, Fluorescência da clorofila a, além de variáveis de crescimento. Os dados foram submetidos à análise de variância (ANOVA, p < 0,05) e as médias comparadas pelo teste de Tukey (p < 0,05), além dos cálculos de índice de plasticidade fenotípica (IPF). Os resultados mostraram que sob temperatura baixa as perdas de biomassa foram maiores que sob temperatura alta em ambas as espécies, o mesmo ocorreu em relação aos danos nas membranas. Por outro lado, a capacidade fotossintética da espécie C3 foi mais estável nas diferentes temperaturas testadas, enquanto que a espécie C4 apresentou um aumento significativo a 40ºC e uma redução significativa a 20ºC. Concluindo, o conjunto de resultados indicou que a temperatura baixa causou maiores danos a ambas as espécies, particularmente na espécie C4. Por outro lado, ambas as espécies mostraram maior capacidade de aclimatação a temperatura elevada. De forma geral, a espécie C4 apresentou uma plasticidade fenotípica comparável a espécie C3.
14

Stable Isotopes and Metabolite Profiles as Physiological Markers for the Drought Stress Sensitivity in Douglas-Fir Provenances (Pseudotsuga menziesii (MIRB.) FRANCO)

Jansen, Kirstin 17 December 2018 (has links)
In Mitteleuropa werden zukünftig häufigere Trocken- und Hitzeperioden mit wirtschaftlichen Einbußen in der Waldwirtschaft erwartet. Die Douglasie (Pseudotsuga menziesii (Mirb.) Franco) wird als Alternative für die wirtschaftlich bedeutsame, jedoch trockenheitsempfindliche Fichte diskutiert (Picea abies (L.) H.Karst.). Zwei Unterarten, die Küsten- (FDC) und die Inlandsdouglasie (FDI), sind im ausgedehnten natürlichen Verbreitungsgebiet in Nordamerika beheimatet, welches ein großes Potenzial für die Auswahl produktiver und trockenresistenter Herkünfte bietet. Unser Ziel war, die Trockenreaktion verschiedener Douglasienherkünfte unter Verknüpfung morphologischer und physiologischer Parameter und die der Trockenheitsresistenz bzw. -empfindlichkeit zugrundeliegenden Mechanismen zu erforschen. Ein Herkunftsversuch in Südwestdeutschland ermöglichte die Untersuchung 50-jähriger Douglasien verschiedener Herkünfte entlang eines Höhengradienten. Unter kontrollierten Bedingungen simulierten wir die Effekte einer Hitzewelle auf Jungbäume zweier Provenienzen. Wir analysierten die Kohlenstoff- und Sauerstoff-Stabilisotopenzusammensetzung, den Gaswechsel der Blätter, Veränderungen im Stoffwechsel und das Baumwachstum. Unsere Ergebnisse zeigen bei FDC aus humiden Regionen hohe Wachstumseinbußen unter Trockenheit und moderat bis stark verringerte stomatäre Leitfähigkeit, unterstützt durch Photoprotektion. FDC aus Regionen mit starker Sommertrockenheit reagierten kaum mit Stomataschluss und Wachstumseinbußen auf Trockenheit, jedoch mit starker Osmoregulation und Monoterpen-Emissionen, welche zur Trockenresistenz beitragen könnten. FDI aus einer ariden Region zeigten hohe An, geringes Wachstum und stark antioxidative und photoprotektive Mechanismen. Die Herkünfte unterscheiden sich stark in ihrer Trockenreaktion und ihren Schutzmechanismen. Der Anbau trockenresistenter Herkünfte wird an Standorten von Vorteil sein, für die eine Häufung von ariden Sommerperioden vorhergesagt wird. / In Central Europe, more frequent periods of dry and hot weather are expected in the future with economic losses in the forestry sector. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is discussed as a timber species alternative to the economically important but drought-sensitive spruce (Picea abies (L.) H. Karst.). Two subspecies, the coastal (FDC) and the interior Douglas-fir (FDI), are native to an extensive natural range in North America, offering a great potential for the selection of productive and drought tolerant provenances. Our goal was to investigate the drought response of different Douglas-fir provenances on the morphological and physiological level, as well as the mechanisms underlying drought resistance or susceptibility. A provenance trial in southwestern Germany established in 1958 allowed the study of 50-year-old Douglas-fir trees of diverse provenances along a height gradient. Under controlled conditions, we simulated the effects of a heat wave on young trees of two provenances. We analyzed carbon and oxygen stable isotopic composition, leaf gas exchange, changes in metabolism and tree growth. FDC from humid regions responded to drought with strong growth decline and a medium to strong stomatal closure, supported by enhanced instantaneous photoprotection. FDC from regions with very dry summer conditions showed a small growth decline and anisohydric regulation of stomatal conductance under drought, supported by high levels of osmotic adjustment. High monoterpene emissions might contribute to the drought resistance. FDI from an arid region showed high assimilation rates, low growth potential and a high antioxidant, photoprotective, drought and heat protective potential. The provenances differ greatly in their dry reaction and their protective mechanisms. The cultivation of drought resistant crops will be beneficial at sites predicted to accumulate arid summer periods.

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