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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.
1

Mat?ria org?nica no solo favorece o crescimento da alface sob temperaturas estressantes / Lettuce cultivated under stressful temperature conditions

Bento, B?rbara Maria da Cruz 01 December 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-05-22T20:56:29Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) barbara_maria_cruz_bento.pdf: 1640285 bytes, checksum: 25447d41b250514b826ff4b7ea8e2c53 (MD5) / Made available in DSpace on 2018-05-22T20:56:29Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) barbara_maria_cruz_bento.pdf: 1640285 bytes, checksum: 25447d41b250514b826ff4b7ea8e2c53 (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A alface (Lactuca sativa L.) ? sens?vel ?s condi??es clim?ticas, principalmente ? alta temperatura, modificando a sua arquitetura, peso, qualidade e, principalmente a produ??o. A a??o da temperatura do ar ? determinante nas mudan?as dos est?dios de desenvolvimento dos vegetais, interferindo tanto na emiss?o de folhas quanto na mudan?a dos est?dios fenol?gicos, al?m de provocar altera??es morfol?gicas e fisiol?gicas. A faixa de temperatura de 15 a 24 ?C ? considerada adequada ao desenvolvimento da alface, entretanto, quando cultivada em regi?es de temperatura e luminosidade elevadas, esta hortali?a pode deixar de desenvolver todo o seu potencial gen?tico. A aduba??o pode ser utilizada para incrementar a produtividade na cultura da alface. No entanto, os efeitos das condi??es clim?ticas juntamente com a aduba??o e suas influ?ncias no crescimento cultura requerem maior aprofundamento no estudo, pois, o ambiente de cultivo, juntamente com a aduba??o e o componente gen?tico da planta, s?o os grandes respons?veis pelas mudan?as no crescimento, flora??o e senesc?ncia. Assim, objetivou-se verificar o comportamento e padr?o de crescimento de plantas de alface cv. Regina sob diferentes temperaturas e estrat?gias de aduba??es. O estudo foi conduzido em sala de crescimento, em DIC com esquema fatorial 4x6, sendo: quatro temperaturas m?dias constantes para o cultivo da alface (12 ?C; 20 ?C; 23 ?C e 28 ?C) e seis aduba??es (controle, convencional mineral, Geofert - organomineral peletizado, Organomineral UFVJM, esterco de curral curtido e cama de codorna compostada). As plantas foram avaliadas quanto ao crescimento, p?s-colheita e perda de massa fresca em cada ciclo. Nas condi??es do experimento, os tratamentos cama de codorna, esterco de curral e organomineral Geofert promoveram maior crescimento ?s plantas de alface cv. Regina, sendo que essas estrat?gias de aduba??o podem permitir melhor desempenho produtivo das plantas at? mesmo em temperaturas de estresse. Os adubos org?nicos e Geofert s?o alternativas eficientes para o crescimento de plantas de alface cv. Regina e conferem ?s plantas menor perda de massa fresca, quando comparado ? aduba??o mineral convencional. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Lettuce (Lactuca sativa L.) is sensitive to the climatic conditions, mainly to the high temperature, changing its architecture, weight, quality and mainly the production. The action of air temperature is determinant in the changes of the stages of development of the plants, interfering as much in the emission of leaves as in the change of the phenological stages, besides causing morphological and physiological alterations. The temperature ranges of 15 to 24 ? C is considered adequate for the development of lettuce, however, when cultivated in regions of high temperature and luminosity, may fail to develop its full genetic potential. Fertilization can be used to increase productivity in lettuce culture. However, the effects of climatic conditions together with fertilization and its influences on the growth of culture require further study, because the growth environment together with the fertilization and genetic component of the plant are responsible for the changes in growth, flowering and senescence. Thus, objective was to verify the behavior and growth pattern of lettuce cv. Regina under different temperatures and fertilization strategies. The study was conducted in a growth room adopting a completely randomized design (CRD) in 4x6 factorial scheme with four constant average temperatures for lettuce cultivation (12, 20, 23, and 28?C) and six fertilizations (control, conventional mineral, Geofert - pelletized organic mineral, organic mineral from UFVJM, corral manure and composted quail bed). The plants were evaluated for growth, postharvest and loss of fresh mass in each cycle. Under the conditions of the experiment, treatments composed of composted quail bed, corral manure and Geofert promoted higher growth to lettuce plants cv. Regina being that these strategies of fertilization can allow better productive performance of the plants even in temperatures of stress. Organic fertilizers and Geofert are efficient alternatives for the growth of lettuce plants cv. Regina and gives the plants less fresh weight loss when compared to conventional mineral fertilization.
2

Efeito da temperatura e chuva sobre a qualidade da fibra e produtividade de algodão no estado de Mato Grosso / Temperature and rainfall effect on fiber quality and yield of cotton in the State of \"Mato Grosso\", Brazil

Soares, Leonardo Cirilo da Silva 23 June 2015 (has links)
Temperatura e chuva exercem grande influência sobre o crescimento, desenvolvimento e produtividade vegetal. Com o objetivo geral de verificar o efeito da variação da temperatura e chuva sobre a qualidade da fibra e a produtividade de algodão no estado de Mato Grosso, este trabalho analisou conjuntamente dados climatológicos (banco de dados contendo os valores diários de temperatura máxima, mínima e média, e chuva) e dados provenientes de um grupo de experimentos de campo de algodão. A caracterização de diversos genótipos (cultivares e linhagens) de algodão foi realizada em 109 ambientes do estado de Mato Grosso, os quais foram formados pela combinação de três causas de variação: (i) seis locais (Itiquira, Serra da Petrovina, Campo Verde, Campo Novo do Parecis, Sapezal e Sorriso); (ii) quatro épocas de semeadura (05 a 21 de dezembro, 22 de dezembro a 10 de janeiro, 11 a 25 de janeiro, 25 de janeiro a 20 de fevereiro); e (iii) oito safras agrícolas (2003/2004 a 2010/2011). Os quatro cultivares mais frequentes foram selecionados: FiberMax 966, FMT 701, FiberMax 993 e DeltaOpal, testados em 75, 68, 63 e 60 ambientes, respectivamente. Os dados climatológicos, de cada ambiente, foram segmentados em três fases de desenvolvimento do algodoeiro: (i) emergência à primeira flor (E-F1); (ii) primeira flor ao primeiro capulho, mais 21 dias (F1-C1+21D); e (iii) emergência ao primeiro capulho, mais 21 dias (F1-C1+21D). Os resultados de cada fase foram correlacionados com os dados dos experimentos de campo de algodão (produtividade de algodão em caroço, rendimento e qualidade de fibra - índice micronaire, resistência, comprimento e maturidade). Os principais resultados obtidos foram: (i) variações de temperatura e chuva ocorridas durante a fase F1-C1+21D promoveram maior influência sobre produtividade e qualidade de fibra; (ii) o aumento da amplitude térmica interferiu negativamente na produtividade de algodão em caroço, índice micronaire e maturidade de fibra, e positivamente na resistência da fibra; (iii) quando comparadas à temperatura máxima, variações de temperatura mínima foram mais limitantes sobre a produtividade e qualidade de fibra; (iv) temperaturas mínimas inferiores a 20°C interferiram negativamente na produtividade de algodão em caroço, rendimento de fibra, índice micronaire e maturidade; (v) a elevação da temperatura máxima média interferiu positivamente na resistência e negativamente no comprimento de fibra; entretanto extremos de temperatura máxima, acima de 35°C, não foram associados às variações de produtividade e qualidade de fibra; e (vi) o aumento de chuva, em quantidade acumulada e frequência de ocorrência, resultou em elevação da produtividade de algodão em caroço, índice micronaire e maturidade. Como conclusão, o aumento da temperatura mínima e da frequência de ocorrência de chuva promovem o incremento da produtividade e da qualidade da fibra de algodão, ao passo que extremos de temperatura máxima não provocam alterações consistentes no estado de Mato Grosso. / Temperature and rain have great influence on the growth, development and yield of plants. In order to verify the effect of temperature and rainfall on fiber quality and yield of cotton in the State of ´Mato Grosso´, Brazil, climatological data (daily database of maximum, minimum and mean temperature and rainfall) were analyzed with data from a group of cotton field experiments. The characterization of various genotypes (cultivars and lines) of cotton was fulfilled in 109 environments of the State of Mato Grosso, which were formed by the combination of three sources of variation: (i) six locations (´Itiquira´, ´Serra da Petrovina´, ´Campo Verde´, ´Campo Novo do Parecis´, ´Sapezal´ and ´Sorriso´); (ii) four sowing times (5 to 21 December, December 22 to January 10, 11 to 25 January, and after January 26); and (iii) eight growing seasons (2003/2004 to 2010/2011). The four most frequent cultivars were selected: ´FiberMax 966´, ´FMT 701´, ´FiberMax 993´ and ´DeltaOpal´, tested in 75, 68, 63 and 60 environments, respectively. The climatological data, from each environment, were segmented into three stages of cotton development: (i) emergence to first flower (E-F1); (ii) first flower to the first boll, plus 21 days (F1-C1+21d); and (iii) emergency to the first boll, plus 21 days (E-C1+21d). The results of each phase were correlated with the experimental field data of cotton (productivity, lint yield and fiber quality (micronaire index, strength, length and maturity). The main results were: (i) variations of temperature and rainfall during the phase (F1-C1+21d) promoted greater influence on yield and fiber quality; (ii) the increasing of thermic amplitude affected negatively on yield, micronaire index and fiber maturity, and positively the fiber strength; (iii) when compared to the maximum temperature, minimum temperature variations were more restrictive on yield and fiber quality; (iv) values of minimum temperature below 20°C were harmful to yield, lint yield, micronaire index and maturity; (v) the maximum temperature had a positive influence in resistance and a negative influence on the fiber length; however, extreme maximum temperature above 35°C wasn\'t associated to variations on yield and fiber quality; and (vi) the increasing of rainfall, in height and occurrence frequency, influenced the rising in cotton productivity, micronaire index and maturity. In conclusion, the increasing of minimum temperature and frequency of rainfall occurrence promote the increment of cotton productivity and fiber quality, while maximum temperature extremes caused no consistent changes in the State of Mato Grosso.
3

Efeito da temperatura e chuva sobre a qualidade da fibra e produtividade de algodão no estado de Mato Grosso / Temperature and rainfall effect on fiber quality and yield of cotton in the State of \"Mato Grosso\", Brazil

Leonardo Cirilo da Silva Soares 23 June 2015 (has links)
Temperatura e chuva exercem grande influência sobre o crescimento, desenvolvimento e produtividade vegetal. Com o objetivo geral de verificar o efeito da variação da temperatura e chuva sobre a qualidade da fibra e a produtividade de algodão no estado de Mato Grosso, este trabalho analisou conjuntamente dados climatológicos (banco de dados contendo os valores diários de temperatura máxima, mínima e média, e chuva) e dados provenientes de um grupo de experimentos de campo de algodão. A caracterização de diversos genótipos (cultivares e linhagens) de algodão foi realizada em 109 ambientes do estado de Mato Grosso, os quais foram formados pela combinação de três causas de variação: (i) seis locais (Itiquira, Serra da Petrovina, Campo Verde, Campo Novo do Parecis, Sapezal e Sorriso); (ii) quatro épocas de semeadura (05 a 21 de dezembro, 22 de dezembro a 10 de janeiro, 11 a 25 de janeiro, 25 de janeiro a 20 de fevereiro); e (iii) oito safras agrícolas (2003/2004 a 2010/2011). Os quatro cultivares mais frequentes foram selecionados: FiberMax 966, FMT 701, FiberMax 993 e DeltaOpal, testados em 75, 68, 63 e 60 ambientes, respectivamente. Os dados climatológicos, de cada ambiente, foram segmentados em três fases de desenvolvimento do algodoeiro: (i) emergência à primeira flor (E-F1); (ii) primeira flor ao primeiro capulho, mais 21 dias (F1-C1+21D); e (iii) emergência ao primeiro capulho, mais 21 dias (F1-C1+21D). Os resultados de cada fase foram correlacionados com os dados dos experimentos de campo de algodão (produtividade de algodão em caroço, rendimento e qualidade de fibra - índice micronaire, resistência, comprimento e maturidade). Os principais resultados obtidos foram: (i) variações de temperatura e chuva ocorridas durante a fase F1-C1+21D promoveram maior influência sobre produtividade e qualidade de fibra; (ii) o aumento da amplitude térmica interferiu negativamente na produtividade de algodão em caroço, índice micronaire e maturidade de fibra, e positivamente na resistência da fibra; (iii) quando comparadas à temperatura máxima, variações de temperatura mínima foram mais limitantes sobre a produtividade e qualidade de fibra; (iv) temperaturas mínimas inferiores a 20°C interferiram negativamente na produtividade de algodão em caroço, rendimento de fibra, índice micronaire e maturidade; (v) a elevação da temperatura máxima média interferiu positivamente na resistência e negativamente no comprimento de fibra; entretanto extremos de temperatura máxima, acima de 35°C, não foram associados às variações de produtividade e qualidade de fibra; e (vi) o aumento de chuva, em quantidade acumulada e frequência de ocorrência, resultou em elevação da produtividade de algodão em caroço, índice micronaire e maturidade. Como conclusão, o aumento da temperatura mínima e da frequência de ocorrência de chuva promovem o incremento da produtividade e da qualidade da fibra de algodão, ao passo que extremos de temperatura máxima não provocam alterações consistentes no estado de Mato Grosso. / Temperature and rain have great influence on the growth, development and yield of plants. In order to verify the effect of temperature and rainfall on fiber quality and yield of cotton in the State of ´Mato Grosso´, Brazil, climatological data (daily database of maximum, minimum and mean temperature and rainfall) were analyzed with data from a group of cotton field experiments. The characterization of various genotypes (cultivars and lines) of cotton was fulfilled in 109 environments of the State of Mato Grosso, which were formed by the combination of three sources of variation: (i) six locations (´Itiquira´, ´Serra da Petrovina´, ´Campo Verde´, ´Campo Novo do Parecis´, ´Sapezal´ and ´Sorriso´); (ii) four sowing times (5 to 21 December, December 22 to January 10, 11 to 25 January, and after January 26); and (iii) eight growing seasons (2003/2004 to 2010/2011). The four most frequent cultivars were selected: ´FiberMax 966´, ´FMT 701´, ´FiberMax 993´ and ´DeltaOpal´, tested in 75, 68, 63 and 60 environments, respectively. The climatological data, from each environment, were segmented into three stages of cotton development: (i) emergence to first flower (E-F1); (ii) first flower to the first boll, plus 21 days (F1-C1+21d); and (iii) emergency to the first boll, plus 21 days (E-C1+21d). The results of each phase were correlated with the experimental field data of cotton (productivity, lint yield and fiber quality (micronaire index, strength, length and maturity). The main results were: (i) variations of temperature and rainfall during the phase (F1-C1+21d) promoted greater influence on yield and fiber quality; (ii) the increasing of thermic amplitude affected negatively on yield, micronaire index and fiber maturity, and positively the fiber strength; (iii) when compared to the maximum temperature, minimum temperature variations were more restrictive on yield and fiber quality; (iv) values of minimum temperature below 20°C were harmful to yield, lint yield, micronaire index and maturity; (v) the maximum temperature had a positive influence in resistance and a negative influence on the fiber length; however, extreme maximum temperature above 35°C wasn\'t associated to variations on yield and fiber quality; and (vi) the increasing of rainfall, in height and occurrence frequency, influenced the rising in cotton productivity, micronaire index and maturity. In conclusion, the increasing of minimum temperature and frequency of rainfall occurrence promote the increment of cotton productivity and fiber quality, while maximum temperature extremes caused no consistent changes in the State of Mato Grosso.
4

Localized Heat Therapy Improves Mitochondrial Function in Human Skeletal Muscle

Marchant, Erik D. 15 April 2022 (has links)
Physical activity results in various types of stress in skeletal muscle including energetic, oxidative, and heat stress. Acute exposure to stress impairs skeletal muscle mitochondrial function. In contrast, chronic intermittent exposure to mild stress through exercise training results in increased mitochondrial content and respiratory capacity. While oxidative and energetic stress have received much attention regarding their long-term effect on skeletal muscle mitochondria, heat stress is not well understood. The purpose of this work was to investigate the effects of localized heat therapy on human skeletal muscle mitochondria, and to compare these effects to those of high-intensity interval exercise training. To accomplish this purpose, 35 subjects were assigned to receive 6 weeks of sham therapy, heat therapy, or exercise training; all localized to the quadriceps muscles of the right leg. Two-hour sessions of short-wave diathermy were used for the heat therapy, and identical sessions were used for sham therapy, but the diathermy units were not activated. Forty-minute sessions of single-leg extension, high-intensity interval training were used for the exercise intervention. All interventions took place three times per week. Muscle biopsies were performed at baseline, and after three and six weeks of intervention. Muscle fiber bundles were isolated and permeabilized for measurement of oxygen consumption via high-resolution respirometry. The primary finding of this work was that heat therapy improves mitochondrial respiratory capacity by 24.8 ± 6.2% compared to a 27.9 ± 8.7% improvement following exercise training. Both heat and exercise significantly increased mitochondrial respiration compared to baseline measures (p<0.05). Fatty acid oxidation and citrate synthase activity were also increased following exercise training by 29.5 ± 6.8% and 19.0 ± 7.4%, respectively (p<0.05). However, contrary to our hypothesis, heat therapy did not increase fatty acid oxidation or citrate synthase activity. Neither heat nor exercise training increased mitochondrial respiratory protein content. Overall these results suggest that heat therapy significantly improves mitochondrial function, but not to the same degree as exercise training.
5

Les relations sol/plantes en forêts méditerranéennes : approche bioclimatique des déterminants de la structuration fonctionnelle des communautés microbiennes des sols et de leurs réponses à un double stress hydrique et thermique en région provençale calcaire / Soil-plant relationships in Mediterranean forests : bioclimatic assessment of the driving factors of soil microbial community functional structure and response to a water and thermic stress in limestome-based Provence area

Pailler, Alexia 18 December 2013 (has links)
En contexte forestier méditerranéen au sein de la région provençale calcaire (sud de la France), les relations sol/structure fonctionnelle catabolique des communautés microbiennes/communautés végétales ont été abordées selon différentes échelles bioclimatiques : un gradient latitudinal et altitudinal, et une échelle écosystémique restreinte à différentes séries de chênes pubescents. Ces travaux ont permis d’estimer les contributions respectives (et de leurs interactions) de la structure et de la composition de la végétation et des variables abiotiques dans la détermination des propriétés fonctionnelles des communautés microbiennes des sols. Dans le contexte des changements climatiques globaux, cette même stratégie a été mise en œuvre pour estimer les incidences, sur les potentiels cataboliques et les profils fonctionnels, d’un double stress hydrique et thermique ex situ, mimétique d’une vague de chaleur. Pour les diverses échelles spatiales, nos résultats ont mis en évidence la prépondérance de la part d’interaction entre la végétation et les variables abiotiques épigées et hypogées dans la structuration fonctionnelle des communautés microbiennes. Suite au stress, une diminution globale de leurs potentiels cataboliques a pu être observée. Néanmoins, nos résultats ont révélé une robustesse différentielle des relations entre la végétation et la structure fonctionnelle des communautés microbiennes selon le stade d’évolution de la végétation et de la nature des espèces constitutives de ces formations au niveau de leur dynamique d’occupation spatiale. Ceci pourrait atténuer ou exacerber les effets du réchauffement climatique sur les écosystèmes forestiers méditerranéens. / In Mediterranean forest ecosystems in the limestome-based Provence area (south of France), soil-microbial community functional catabolic structure-vegetation relationships were assessed based on different bioclimatic scales, across a latitudinal gradient, an elevation gradient, and at a restricted ecosystemic scale focusing on Pubescent oak forest stands. The respective parts (and their interactions) of the vegetation composition and structure and the abiotic variables in their functional profiles were investigated. Furthermore, in the context of climate change, this same strategy was used to investigate the effects of an ex situ water and thermic stress, mimetic to a heatwave event on microbial community catabolic potentials and functional profiles. For all the considered scales, our results highlighted the major part of the interactions between vegetation and abiotic aboveground-belowground variables in the determination of soil microbial community functional structure. Drought induced a decrease in their potential catabolic activities. Nevertheless, our results revealed a varying robustness of the interactions between vegetation and soil microbial functional structure based on the dynamic step of the evolution of the forest stands and on the type of their constitutive species. This may mitigate or exacerbate climate change effects on Mediterranean forest ecosystems.

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