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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.
51

Express?o g?nica relacionada ? produ??o de ?leo essencial e avalia??o do metabolismo de Mentha arvensis L. sob diferentes condi??es de cultivo / Gene expression related to production of essential oil and evaluation of Mentha arvensis metabolism under different conditions of cultivation

Souza, Marco Andre Alves de 18 January 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-03-30T12:28:08Z No. of bitstreams: 1 2010 - Marco Andre Alves de Souza.pdf: 5657340 bytes, checksum: becf46e090a1ebcc4a731b733c77fb6a (MD5) / Made available in DSpace on 2017-03-30T12:28:08Z (GMT). No. of bitstreams: 1 2010 - Marco Andre Alves de Souza.pdf: 5657340 bytes, checksum: becf46e090a1ebcc4a731b733c77fb6a (MD5) Previous issue date: 2010-01-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The cultivation of aromatic specimens for obtaining essential oils have great economic importance, mainly by increasing demand in the food, cosmetic and pharmaceutical industry. Brazil is the largest producer of essential oil, however, is what earns less in money value, because, its production is mainly of orange essential oil, with low added value. The essential oil of M. arvensis is rich in menthol (70-80%), a natural products with higher demand in daily life of modern man. Currently, Brazil has become a major importer of menthol which has contributed negatively to the brazilian trade balance. Thus, for the development of this work was chosen to be a specimens of economic interest and social demand, the Mentha arvensis. The purpose of study was to evaluate whether changes in light intensities and different levels of phosphorus promote changes in biomass production and nutrition, with consequences for the biosynthesis of essential oils. We also analyzed the influence of leaf age on the quality of essential oil. To this end, the plant of M. arvensis was grown under the effect of different conditions, which allowed the analysis of the levels of soluble fractions, of photosynthetic pigments, the activities of enzymes related to nitrogen assimilation and the anatomical and histochemical study of trichomes, morphological structure where it is produce the essential oil. The study also included analysis of the expression of genes related to the route of menthol synthesis. The essential oil was obtained by extraction with hydrodestillation in modified Clevenger and the chemical analysis of substances obtained by GC-MS. The Kovats index was used to collaborate in identification of the main substances in essential oil. The results showed that the essential oil quality is determined by physiological conditions and leaf age and that the production is dependent on the synthesis efficiency and density of trichomes on the leaves. In addition, it was found that different concentrations of phosphorus affected some aspects of plant metabolism, which reflected the production of biomass in the soluble fraction, with consequences on production and quality of essential oils. Also showed that variations in light levels affected the expression of six of the eight genes involved in the route of synthesis of menthol, in plants of M. arvensis and that changes in gene expression are probably associated with a transcription factor, which could be acting on the whole pathway. All of this information showed that environmental conditions and / or nutritional affected some aspects of plant metabolism, which reflected the production of biomass, of trichomes and on the expression of genes related to the route of menthol, which reflect on the quality and the production of essential oils / O cultivo de esp?cies arom?ticas para a obten??o de ?leos essenciais tem grande import?ncia econ?mica, principalmente, pela crescente demanda nas ind?strias de alimentos, de cosm?ticos e a farmac?utica. O Brasil ? o maior produtor de ?leo essencial, entretanto, ? o que menos arrecada em valores monet?rios, pois, sua produ??o ? basicamente de ?leo essencial de laranja, com baixo valor agregado. O ?leo essencial de Mentha arvensis L. ? rico em mentol (70-80%), uma dos produtos naturais com maior demanda no dia-a-dia do homem moderno. Atualmente, o Brasil tornou-se um grande importador de mentol o que tem contribu?do negativamente para a balan?a comercial brasileira. Deste modo, para o desenvolvimento deste trabalho escolheu-se a planta M. arvensis. O objetivo do estudo foi avaliar se varia??es nas intensidades luminosas e diferentes concentra??es de f?sforo promovem altera??es na produ??o de biomassa e em aspectos nutricionais, com reflexos na bioss?ntese de ?leos essenciais. Tamb?m foi avaliada a influ?ncia da idade da folha sobre a qualidade do ?leo essencial. Com esta finalidade, a planta de M. arvensis foi cultivada sob o efeito de diferentes condi??es, o que permitiu a an?lise dos teores das fra??es sol?veis, dos pigmentos fotossint?ticos, das atividades das enzimas relacionadas com a assimila??o do nitrog?nio e o estudo histoqu?mico e anat?mico dos tricomas secretores, estrutura morfol?gica onde ? produzido o ?leo essencial. Tamb?m foram realizadas analises da express?o dos genes relacionados com a rota de s?ntese do mentol. O ?leo essencial foi obtido por hidrodestila??o em Clevenger modificado e as analises qu?micas das subst?ncias realizadas por CG/EM. A utiliza??o do ?ndice de Kovats auxiliou na identific??o das principais subst?ncias no ?leo essencial. Os resultados permitiram concluir que a qualidade do ?leo essencial ? determinada pelas condi??es fisiol?gicas e a idade das folhas e que a produ??o ? dependente da efici?ncia de s?ntese e a densidade de tricomas secretores nas folhas. Al?m disso, foi constatado que as diferentes concentra??es de f?sforo afetaram alguns aspectos do metabolismo vegetal, os quais refletiram na produ??o de biomassa, nas fra??es sol?veis, com conseq??ncias na produ??o e qualidade dos ?leos essenciais. Tamb?m, mostraram que varia??es nos n?veis de luminosidade afetaram a express?o de seis entre os oito genes envolvidos com a rota de s?ntese do mentol, em plantas de M. arvensis e que as altera??es na express?o dos genes provavelmente est?o associados a um fator de transcri??o, o qual deve estar atuando sobre toda a rota metab?lica
52

Ecologically Engineered Primary Production in Central Queensland, Australia - Integrated Fish and Crayfish Culture, Constructed Wetlands, Floral Hydroponics, and Industrial Wastewater.

Roe, Brett, b.roe@cqu.edu.au January 2005 (has links)
The issue of sustainability has greatest significance in the midst of unilateral bio-socioeconomic degradation resulting from intense and increasing societal pressures placed on the unified global ecology. In such an environment, sustainable development seeks to manage natural resources within a free market economy, aiming to meet the needs of today's population, and to protect and enhance current resource quality and abundance. In this light, techniques of integrated sustainable primary production and wastewater management are the subject matters of this applied research. There are many researchable issues which could be addressed within the subject matter. The first focus in the research scope was driven by the most severe sustainability issue facing Central Queensland (Australia) in 2000: the depletion and degradation of freshwater supplies. Central Queensland (CQ) is an arid sub-tropical region that has suffered from a marked reduction in rainfall and increase in temperature over the last 100 years, {Miles, 2004 #172}, and by the year 2000, conditions had been exacerbated by eight years of severe drought and warmer than average temperatures and resulted in widespread animal and crop failures due to freshwater shortages. Such a problem required a multi-faceted ecological, social, and economic approach. Hence, research centred on investigating the science of integrating regional water-related industries and agribusiness, and biodiverse ecosystems to achieve water and wastewater reuse applications, and associated eco-socioeconomic benefits. Specifically, this research investigates the integration of (a) electrical power station wastewater (b) barramundi culture, (c) red claw culture, (d) constructed wetlands (for water quality management and habitat creation), and (e) hydroponic flower culture. This research produced outcomes of integrated water and wastewater reuse and recycling, marketable agriproducts production (fish, crayfish, and flowers), water and wastewater reuse and conservation, wetland primary production, carbon dioxide sequestration, aquatic pollution control, and biodiversity creation and support. Successful design and management, experimental trialing and evaluation of system components and subjects, and the development of a knowledge base including static and dynamic system models, represent advances in respective research areas, and underpin the emerging discipline of integrated systems approaches to eco-socioeconomic development. Additionally, several gaps in the current body of knowledge regarding integrated systems were filled, and interactive management tools were developed. Apart from this study, the integration of technologies (as described above) has not, to this author's knowledge, been accomplished.
53

Processus et mécanismes physico-chimiques et biologiques responsables du fractionnement des isotopes du calcium / Process and mechanisms physico-chemicals and biologicals that fractionate calcium isotopes

Cobert, Florian 15 June 2012 (has links)
Cette thèse a pour but d’identifier et de préciser les processus biotiques et abiotiques qui contrôlent le comportement du Ca et plus spécifiquement le fractionnement des isotopes du Ca à l’interface géosphère-biosphère-hydrosphère en combinant différentes études expérimentales (hydroponiques et microcosmes). Les résultats obtenus lors des expérimentations hydroponiques ont permis d’identifier 3 niveaux de fractionnement des isotopes du Ca au sein des végétaux, ces 3 niveaux de fractionnement sont induits par des mécanismes physico-chimiques qui enrichissent les organes de végétaux en 40Ca.Les résultats des expérimentations hydroponiques montrent également que l’évolution de la composition isotopique du Ca de la solution nutritive et des plantes suit une loi de fractionnement des isotopes du Ca à l’équilibre (αplantes/solution nutritive = 0,99858). Les expérimentations abiotiques en microcosmes, quant à elles, indiquent que la dissolution de l’apatite par des acides organiques ou inorganiques n’influence pas la signature isotopique en Ca de la phase dissoute résultante. À l’inverse, lors des expérimentations biotiques en microcosmes, seule l’action combinée des racines de pins et des bactéries sur un substratum d’apatite enrichit la solution qui percole en 44Ca de 0,22‰. / The aim of this thesis is to identify and to specify biotic and abiotic processes affecting the Ca behavior and specifically the Ca isotope fractionation at the geosphere/biosphere/hydrosphere interface by combining different experimental studies (hydroponic and microcosm).Results of hydroponic experiments allow to identify three Ca isotopic fractionation levels, which are driven by physico-chemical mechanisms and enrich the plant organs in the light 40Ca isotope. Moreover, the evolution of Ca isotopic composition of nutrient solution and plants follow an equilibrium law (αplants/nutrient solution = 0.99858).Abiotic column experiments show no Ca isotopic fractonation during apatite disolution, whatever the nature of the acid (mineral or organic). At the opposite, during biotic microcosm experiments, only the combined action of roots of scots pines and bacteria on apatite substratum enrich the percolate solution in heavy 44Ca of 0.22‰.
54

Avaliação da qualidade de forragem hidropônica de centeio, cevada e ervilhaca / Evaluation of the quality of hydroponics forage Hordeum vulgare L. ,Secale cereale L. and Vicia sativa L.

Zorzan, Marise Helena Saldanha 10 February 2006 (has links)
It was carried an experiment, in the Fitotecnia Department of the Federal University of Santa Maria (UFSM) - RS, with objective to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L.), cultivated in hydroponic, during of autumn and winter and to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L) joined to a legume (Vicia sativa L.), cultivated in hydroponic, during autumn and winter. It was adopted the experimental delineation entirely casuistic with four repetitions. The data had been submitted to the variance analysis. The averages of the qualitative variables had been compared among themselves for Tukey test with 5% of error probability. The hydroponic Secale cereale L forage showed bigger dry mass and mineral substance in autumn and winter, surpassing the Hordeum vulgare L forage, Hordeum vulgare L.: intercropping+Vicia sativa L and Secale cereale L+Vicia sativa L. Hydroponic Secale cereale L forage intercropping+Vicia sativa L 150 presented bigger dry mass than the others treatments, however, the mineral substance resulted in minors values, what negatively differentiated in relation the Secale cereale L forage. The biggest fiber value in neutral detergent found, was in the hydroponic Hordeum vulgare L. forage, although it did not show significant difference in relation to the others treatments. The hydroponic Secale cereale L forage presented a bigger rude protein value in relation to the others treatments. The hydroponic forages it did not show significant difference in relation to energetic value and value of phosphorus. The biggest value of calcium and magnesium had been found in the hydroponic Secale cereale L. forage. The Hordeum vulgare L. produced in the 2002 winter, presented minors potassium value, differing significantly from the Hordeum vulgare L intercropping + Vicia sativa L 300 and Secale cereale L + Vicia sativa L 150. / Foi realizado um experimento, no Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM) RS, com objetivo de avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio), cultivadas em hidroponia, no período de outono e inverno e avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio) consorciadas a uma leguminosa (ervilhaca), cultivadas em hidroponia, no período de outono e inverno. Adotou-se o delineamento experimental inteiramente casualizado com quatro repetições. Os dados obtidos foram submetidos à análise de variância. As médias das variáveis qualitativas foram comparadas entre si pelo teste de Tukey a 5% de probabilidade de erro.A forragem hidropônica de centeio apresentou maior massa seca e matéria mineral no outono e inverno, superando a forragem de cevada, consórcio de cevada + ervilhaca e centeio + ervilhaca. O consórcio de forragem hidropônica de centeio + ervilhaca 150 apresentou maior massa seca que os demais tratamentos consorciados, entretanto, a matéria mineral resultou em menores valores, o que diferenciou negativamente em relação à forragem de centeio. O maior teor de fibra em detergente neutro (FDN) encontrado, foi na forragem hidropônica de cevada, apesar de não ter apresentado diferença significativa em relação aos demais tratamentos. A forragem hidropônica de centeio apresentou um maior teor de proteína bruta em relação aos demais tratamentos. As forragens hidropônicas não apresentaram diferença significativa para o valor energético e o teor de fósforo. Os maiores teores de cálcio e magnésio foram encontrados na forragem hidropônica de centeio. A cevada produzida no inverno de 2002 apresentou menores teores de potássio, diferindo significativamente do consórcio de cevada + ervilhaca 300 e centeio + ervilhaca 150.
55

Soro de leite em substituição à solução nutritiva no cultivo da forragem de milho hidropônico / Whey as a substitute of the nutrient solution in the cultivation of hydroponic maize forage

PAULA, Leila de 24 August 2009 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-10-10T13:49:34Z No. of bitstreams: 1 Leila de Paula.pdf: 1268303 bytes, checksum: af643f4a4df7d349324c84fa3aa4f3f1 (MD5) / Made available in DSpace on 2016-10-10T13:51:14Z (GMT). No. of bitstreams: 1 Leila de Paula.pdf: 1268303 bytes, checksum: af643f4a4df7d349324c84fa3aa4f3f1 (MD5) Previous issue date: 2009-08-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to evaluate the productivity and nutritional efficiency of hydroponic forage maize cultivated in whey as nutrient solution. The experiment was carried out in a greenhouse in an entirely randomized experimental design with six treatments and five replications and a control nutrient solution, conventionally employed in this type of cultivation. The other treatments were distributed in different levels of dilution of whey in tap water to get the concentrations of whey at levels of 20, 40, 60, 80 and 100%. Measurements of pH and EC were performed daily. The harvest was done 15 days after germination, being roots plus substrate separated from the shoots. The weight of fresh matter, dry matter, the levels of macronutrients (N, P, K, Ca, Mg and S) and micronutrients (Fe, Cu, Zn and Mn), in addition to Na and Cl of both the shoot and roots were determined. The increase in concentrations of whey promoted reduction in yield of hydroponic forage, increase in levels of N, S and Zn, decrease of K, Ca and Mg and no effect on levels of P, Fe and Cu in the shoot. The levels of P, K, Ca, Mg, S and Cu in the roots were increased. There was no effect on the levels of Zn and Fe. / O objetivo deste trabalho foi avaliar a produtividade e a eficiência nutricional da utilização do soro de leite aplicado como solução nutritiva no cultivo de forragem hidropônica de milho. Realizou-se o experimento em casa de vegetação em delineamento experimental inteiramente casualizado com seis tratamentos e cinco repetições, sendo o tratamento controle uma solução nutritiva convencionalmente empregada nesse tipo de cultivo. Os demais tratamentos foram distribuídos em diferentes níveis de diluição do soro de leite em água potável, avaliando-se as concentrações de 20, 40, 60, 80 e 100% de soro de leite. Durante o experimento foram realizadas medições diárias de pH e CE das soluções drenadas. A colheita foi feita com 15 dias após a germinação, onde se separou a parte aérea do substrato com as raízes. Determinou-se o peso de matéria fresca, peso de matéria seca, os teores de macro (N, P, K, Ca, Mg e S) e micronutrientes (Fe, Cu, Zn e Mn), além dos elementos que se mostraram em níveis tóxicos (Na e Cl), tanto da parte aérea como da parte radicular. O aumento nas concentrações de soro de leite promoveu redução na produtividade da forragem hidropônica. Observou-se com o aumento nas concentrações de soro de leite, acréscimo nos teores de N, S e Zn, com redução de K, Ca e Mg, além de não apresentar efeito nos teores de P, Fe e Cu, na parte aérea. Na porção radicular houve acréscimo nos teores de P, K, Ca, Mg, S e Cu não apresentando efeito nos teores de Zn e Fe.
56

Propagação de pitangueira via miniestaquia / Propagation of Surinam Cherry by minicutting

Carvalho, Geniane Lopes 03 December 2012 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-09-28T13:49:24Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Geniane_Lopes_Carvalho.pdf: 819405 bytes, checksum: f22f88ad943127cecb020f19b9495b8a (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-09-28T18:55:05Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Geniane_Lopes_Carvalho.pdf: 819405 bytes, checksum: f22f88ad943127cecb020f19b9495b8a (MD5) / Made available in DSpace on 2016-09-28T18:55:05Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Geniane_Lopes_Carvalho.pdf: 819405 bytes, checksum: f22f88ad943127cecb020f19b9495b8a (MD5) Previous issue date: 2012-12-03 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / O presente trabalho teve como objetivo estudar a propagação de mudas clonadas de pitangueira preta, oriundas da técnica de miniestaquia, sendo realizados três experimentos, organizados em três artigos. O primeiro artigo aborda o enraizamento de miniestacas de seleção de pitangueira preta obtidas na Embrapa Clima Temperado, com diferentes concentrações de ácido indolbutírico (0, 1000, 2000 mg.L-1) associado a dois tipos de ramos (miniestacas herbáceas e lenhosas). Foi avaliada a porcentagem de sobrevivência e enraizamento, número de raízes, comprimento de raízes, número de brotações e comprimento das brotações. Foi observado influência positiva do regulador de crescimento no enraizamento das miniestacas, sendo a concentração de 2000 mg L-1 a mais eficiente com o material herbáceo. Quanto ao segundo artigo, foi testado na concentração pré-definida do primeiro capítulo, com ramos herbáceos com e sem a presença do ápice, com delineamento de cinco repetições de 30 miniestacas cada. Foram avaliadas a porcentagem de sobrevivência, enraizamento, número de raízes, comprimento de raízes, número de brotações e comprimento das brotações. Foi observada diferença significativa nas miniestacas apicais que apresentaram maior porcentagem de enraizamento, com médias entre 80 e 100%. No terceiro artigo, foi testada a dinâmica de enraizamento de miniestacas de pitangueira, no período de dois meses, a partir de 20 miniestacas avaliadas semanalmente, sendo as variáveis analisadas: número de miniestacas com primórdios radiculares (intumescência e pontos brancos na lesão realizada na base); porcentagem de enraizamento; número de raízes; comprimento de raízes; e raízes com mais de um centímetro. As miniestacas demonstraram um aumento gradativo do enraizamento de acordo com o tempo de cultivo. Conclui-se, que com sete semanas as miniestacas estão aptas ao transplante. / The present experiment was to study some aspects related to the propagation and growth of seedlings pitangueira, from cuttings. For this, there were three chapters. The first article discusses the rooting of cuttings selection Cherry Surinam black courtesy Embrapa Clima Temperado, with different concentrations of indole butyric acid (IBA) (0, 1000, 2000 mg.L1) associated with two kinds of branches (cuttings and herbaceous woody). It was evaluated the survival and rooting percentage, number of roots, root length, number of shoots and shoot length. It was observed positive influence of growth regulators on rooting, and the concentration of 2000 mg L-1 to more efficient with herbaceous material. The second article was tested at a concentration of predefined first chapter, herbaceous branches with and without the presence of the apex, design with five replicates of 30 cuttings each. It was evaluated the survival and rooting percentage, number of roots, root length, number of shoots and shoot length. Significant difference in apical cuttings that had higher rooting percentage, average between 80 and 100%. In the third article, was tested to determine the optimization time of rooting of cuttings of Surinam cherry, within two months, 20 cuttings were evaluated throughout the week and the variables analyzed were number of cuttings to root primordia (swelling and white spots on injury held at the base), rooting percentage, number of roots, length of roots and roots with more than an centimeters. In general, the cuttings have shown a gradual increase in growth according to the cultivation time. It was concluded that seven weeks the cuttings were able to transplant in plastic bags forming a seedling quality.
57

Estresse em arroz (Oryza sativa L.): Correlação dos efeito de dois ambientes de cultivo. / Stress in rice (Oryza sativa L.): Correlation of the effect of two culture environments

Danielowski, Rodrigo 23 August 2013 (has links)
Made available in DSpace on 2014-08-20T14:06:13Z (GMT). No. of bitstreams: 1 dissertacao_rodrigo_danielowski.pdf: 1497530 bytes, checksum: fb08b2775f06eaa51226b61c30eb11ec (MD5) Previous issue date: 2013-08-23 / Rice (Oryza sativa. L) is the second most produced cereal worldwide. Soil salinity is one of the most severe abiotic stresses for various crop species. Currently, 6% of arable land on the planet have a limitation due to salinity levels in the soil, it is estimated that by the year 2050, 50% of agricultural soils present limitations due to soil salinity. Rice is one of the crops most sensitive to soil salinity, reductions in productivity are observed at levels of electrical conductivity of 3.0 dS m-1. The hydroponic growing systems are being increasingly used in scientific studies, and a major advantage of this technique is the control of the studied factors and homogeneity of the environment. This study aimed to evaluate genotypes of rice germplasm bank of EMBRAPA temperate in two hydroponic growing systems effecting the correlation of the results obtained in the two systems. The one experiment was conducted in a greenhouse and the second in a room with controlled temperature and photoperiod. The nutrient solution used in the experiments was YOSHIDA et al. (1976) with some adaptations, and salinity levels used were 0, 30, 60 and 90 mM NaCl. The correlation study was conducted with 24 genotypes evaluated in two experiments, adopting also only 0, 30 and 60 mM as dose factors. The two cultivation environments provided genotype variation of the response as a function of NaCl concentration levels. The cropping system in a controlled environment at the level of 90 mM caused the death of almost all plants. The correlation study revealed no association between the two culture environments, should be made a further study in field conditions to validate and compare the efficiency of the methods. / O arroz (Oryza sativa .L) é o segundo cereal mais produzido no mundo. A salinidade dos solos é um dos estresses abióticos mais severos para diversas espécies cultivadas. Atualmente 6 % das áreas agricultáveis do planeta apresentam limitação devido aos níveis de salinidade presentes no solo, estima-se que até o ano de 2050, 50% dos solos agricultáveis apresentem limitações devido a salinidade dos solos. O arroz é uma das culturas mais sensíveis a salinidade dos solos, reduções na produtividade são observados em níveis de condutividade elétrica de 3,0 dS m-1. Os sistemas de cultivo hidropônico vem sendo cada vez mais utilizados em estudos científicos, sendo que uma das principais vantagem desta técnica, é o controle dos fatores estudados e a homogeneidade do ambiente. O presente trabalho teve como objetivo avaliar genótipos de arroz do banco de germoplasma da EMBRAPA clima temperado, em dois sistemas de cultivo hidropônico efetuando-se a correlação dos resultados obtidos nos dois sistemas. O experimento um foi conduzido em casa de vegetação e o segundo em ambiente com controle de fotoperíodo e temperatura. A solução nutritiva utilizada nos experimentos foi YOSHIDA et al. (1976) com algumas adaptações, e os níveis de salinidade empregados foram de 0, 30, 60 e 90 mM de NaCl. O estudo das correlações dos resultados foi realizado com os 24 genótipos que foram avaliados nos dois experimentos, adotando-se também apenas os nível de 0, 30 e 60 mM do fator dose. Os dois ambientes de cultivo proporcionaram variação da resposta dos genótipos em função dos níveis da concentração de NaCl. O sistema de cultivo em ambiente controlado no nível de 90 mM causou a morte de quase todas as plantas. O estudo da correlação não revelou associação entre os dois ambientes de cultivo, devendo-se realizar um próximo estudo em condições de campo para validar e comparar a eficiência dos métodos.
58

Avaliação da qualidade de forragem hidropônica de centeio, cevada e ervilhaca / Evaluation of the quality of hydroponics forage hordeum vulgare l. ,secale cereale l. and vicia sativa l.

Zorzan, Marise Helena Saldanha 10 February 2006 (has links)
It was carried an experiment, in the Fitotecnia Department of the Federal University of Santa Maria (UFSM) - RS, with objective to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L.), cultivated in hydroponic, during of autumn and winter and to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L) joined to a legume (Vicia sativa L.), cultivated in hydroponic, during autumn and winter. It was adopted the experimental delineation entirely casuistic with four repetitions. The data had been submitted to the variance analysis. The averages of the qualitative variables had been compared among themselves for Tukey test with 5% of error probability. The hydroponic Secale cereale L forage showed bigger dry mass and mineral substance in autumn and winter, surpassing the Hordeum vulgare L forage, Hordeum vulgare L.: intercropping+Vicia sativa L and Secale cereale L+Vicia sativa L. Hydroponic Secale cereale L forage intercropping+Vicia sativa L 150 presented bigger dry mass than the others treatments, however, the mineral substance resulted in minors values, what negatively differentiated in relation the Secale cereale L forage. The biggest fiber value in neutral detergent found, was in the hydroponic Hordeum vulgare L. forage, although it did not show significant difference in relation to the others treatments. The hydroponic Secale cereale L forage presented a bigger rude protein value in relation to the others treatments. The hydroponic forages it did not show significant difference in relation to energetic value and value of phosphorus. The biggest value of calcium and magnesium had been found in the hydroponic Secale cereale L. forage. The Hordeum vulgare L. produced in the 2002 winter, presented minors potassium value, differing significantly from the Hordeum vulgare L intercropping + Vicia sativa L 300 and Secale cereale L + Vicia sativa L 150. / Foi realizado um experimento, no Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM) RS, com objetivo de avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio), cultivadas em hidroponia, no período de outono e inverno e avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio) consorciadas a uma leguminosa (ervilhaca), cultivadas em hidroponia, no período de outono e inverno. Adotou-se o delineamento experimental inteiramente casualizado com quatro repetições. Os dados obtidos foram submetidos à análise de variância. As médias das variáveis qualitativas foram comparadas entre si pelo teste de Tukey a 5% de probabilidade de erro.A forragem hidropônica de centeio apresentou maior massa seca e matéria mineral no outono e inverno, superando a forragem de cevada, consórcio de cevada + ervilhaca e centeio + ervilhaca. O consórcio de forragem hidropônica de centeio + ervilhaca 150 apresentou maior massa seca que os demais tratamentos consorciados, entretanto, a matéria mineral resultou em menores valores, o que diferenciou negativamente em relação à forragem de centeio. O maior teor de fibra em detergente neutro (FDN) encontrado, foi na forragem hidropônica de cevada, apesar de não ter apresentado diferença significativa em relação aos demais tratamentos. A forragem hidropônica de centeio apresentou um maior teor de proteína bruta em relação aos demais tratamentos. As forragens hidropônicas não apresentaram diferença significativa para o valor energético e o teor de fósforo. Os maiores teores de cálcio e magnésio foram encontrados na forragem hidropônica de centeio. A cevada produzida no inverno de 2002 apresentou menores teores de potássio, diferindo significativamente do consórcio de cevada + ervilhaca 300 e centeio + ervilhaca 150.
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Les apports des métaux traces par les fertilisants chimiques phosphatés dans les sols libanais : investigation sur leur devenir et leur transfert / Imputs of trace metals by chemical phosphoric fertilizers in Lebanese soils : investigation of its modification and mobility

Azzi, Valérie 19 April 2016 (has links)
L'utilisation de machines lourdes et la fertilisation des sols ont été la solution pour améliorer le rendement agricole et augmenter les aires des sols cultivés. Les pays émergeants Est-Méditerranéens souffrent d'un manque crucial des législations et des règlementations qui organisent l'usage des fertilisants chimiques. Cela est principalement dû à l'insuffisance des données sur les caractéristiques des sols et les pratiques agricoles. La fertilisation excessive est devenue une source potentielle de contamination des sols par les éléments traces métalliques (ETM) susceptible de migrer vers les différentes chaines alimentaires. Dans ce cadre, l'Institut de Recherches Agronomiques Libanais (IRAL) avait comme préoccupation principale d'évaluer les risques associés aux apports en ETM issus des engrais phosphatés en usage dans des sols de nature alcaline sous un climat aride à semi-aride. Ainsi, l'investigation sur les engrais phosphatés commercialisés au Liban et les pays voisins ont montré que le cadmium est porté principalement dans une phase sulfate quand cette dernière est présente dans les engrais. L'apport moyen annuel du Cd, Cu, Pb et Zn aux sols est trouvé inferieur aux limites recommandées dans certains pays comme le Brésil et la Grande-Bretagne. Cependant, dans le contexte régional où l'étude est réalisée, cet apport est relativement élevé quand la nature alcaline du sol est prise en considération. Ainsi, une norme établie pour un sol acide n'est pas nécessairement adaptable dans un sol alcalin, sachant que ce dernier est un milieu favorable pour stabiliser les ETM et limiter leurs disponibilités. Les Lactuca sativa (laitues), étant une espèce amplement consommée dans les pays du bassin méditerranéen, ont été choisis comme une espèce cible dans l'objectif de suivre la distribution du cadmium dans les différents tissus de l'espèce et le coefficient de partage entre les compartiments eau, sol et plante. Les effets de la densité des sols, en présence du cadmium et des engrais phosphatés ont été étudiés dans des colonnes de sols cultivés par les laitues. Les caractères morphologiques et physiologiques de la plante, la mobilité du cadmium dans le sol et son transfert vers les laitues, la population microbienne (le nombre de bactéries totaux, champignons totaux, bactéries résistantes au cadmium BRC et micro-organismes solubilisant le phosphore MSP) et l'activité enzymatique des phosphatases alcalines (ALP) et acides et les déshydrogénases (DHA) ont été suivis. La présence du Cd et du phosphore dans le sol a diminué la mobilité du cadmium et la compaction a augmenté l'accumulation du Cd dans la partie aérienne des laitues et l'infiltration des nitrates. La combinaison entre la compaction du sol, la présence de cadmium et du phosphore en même temps a montré une diminution du nombre de bactéries, des champignons totaux et de l'activité d'ALP mais une augmentation du nombre de MSP, de BRC et de l'activité de la phosphatase acide est notablement identifiable. En absence de toute matrice d'interaction avec les ETM et les fertilisants phosphatés autre que les laitues, les effets du cadmium et de l'engrais phosphatés ont été évalués sur les caractères morphologiques et physiologiques des laitues en culture hydroponique et sur l'absorption du cadmium par ces laitues. En présence d'engrais phosphaté, la culture des laitues en hydroponie avait une influence positive sur le développement de ce végétal plus qu'en culture dans le sol. Malgré la croissance rapide des laitues en hydroponie, ce système est désormais une source de cadmium disponible aux laitues puisque ce métal est transféré des racines vers la partie aérienne de Lactuca sativa en induisant des changements morphologiques. / Soil compaction and contamination with heavy metals were the response of the use of heavy machinery and phosphate fertilization to improve and expand agricultural productivity. The Eastern Mediterranean emerging countries suffer from lack in legislations and regulations organizing the chemical fertilizers use. This is due to the insufficient data on soil characteristics and agricultural practices. Thus, excessive fertilization can be considered as potential sources of soil contamination by trace metals susceptible to be transferred to the different food chains. One of the main occupations of the Lebanese Agriculture Research Institute (LARI) was to evaluate the associated risks to the trace metals inputs coming from phosphate fertilizers. The investigation of phosphate fertilizers used in Lebanon and neighboring countries showed that cadmium is well bonded to sulfate-phase when sulfate is present in the fertilizers. The annual average of the deposition of Cd, Cu, Pb and Zn in soil was found lower than the recommended limits in some countries like Brazil and Britain but such contribution is relatively high when considering the alkaline nature of the soil. Thus, norms and legislations for acidic soil cannot be necessarily adaptable and used for alkaline soil knowing that such soil is the best environment to stabilize the metals and limit their bioavailability. Lactuca sativa (lettuce), widely consumed specie in Mediterranean countries, has been chosen as target specie to be studied in order to follow cadmium in different parts of the plants and its partition between water, soil and plants. The effects of the compaction, cadmium and phosphate fertilizers were evaluated on morphological and physiological characteristics of Lactuca sativa cultivated in columns. Cadmium mobility in soil and its transfer to lettuce, the microbial population (the number of total bacteria, total fungi, cadmium resistant bacteria CRB and phosphate solubilizing microorganisms PSM) and the enzymatic activities of alkaline phosphatase (ALP), acid phosphatase and dehydrogenase activity (DHA) were also studied. Cadmium mobility was decreased in the soil amended with cadmium and phosphorus and compaction increased the Cd accumulation in the lettuce's aerial part and the nitrate infiltration. A decrease of the number of total bacteria, fungi, ALP and an increase in the number of PSM, CRB and acid phosphatase activity were observed in the treatment where the soil was compacted and amended with cadmium and phosphate fertilizers. In absence of any interactive matrix with the metals and the phosphate fertilizers other than the lettuces, the effects of cadmium and phosphate fertilizer were evaluated on morphological and physiological characteristics of lettuces grown in hydroponic culture. Cadmium absorption and transfer to aerial part was also studied. The lettuces development's was important in the hydroponic culture more than in soil cultivation in presence of phosphate fertilizer. Despite the rapid growth of lettuces in hydroponic culture, this system is a potential source of bioavailable cadmium that is absorbed by lettuces and transferred to roots and aerial parts conducting to morphological changes.
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The Quest for the Hydroponic Pepper : Applying Design Research Methodology to Develop Support Tools for Successfully Designing a Post-harvest System for a Plant Factory

Antser, Charlie, Lundvall, Kimmy January 2021 (has links)
The world is facing a food shortage as the world’s population increases and arable land decreases. Despite this, the food industry is wasteful, and 30% - 40% of all produced food is lost before reaching the end consumer. Emerging technologies aim to increase the amount of food that can be grown per m2 or allow the growing of food in climates or on lands previously impossible. Four main farming techniques utilising these emerging technologies are Controlled Environment Agriculture, Hydroponic Farming, Urban Farming and Vertical farming. When used together, these techniques form the basis for what can be called a Plant Factory. Despite the positive effects these technologies have on the production rate, few Plant Factories have managed to achieve profitability. By creating support for developing the post-harvesting system for a plant factory, this thesis aims to aid in the development of profitable plant factories. The thesis uses Design Research Methodology to achieve this aim in three parts. The first part identifies the underlying factors of the post-harvesting system affecting plant factory profitability. The second presents a set of support components that will aid the developers to improve key factors affecting profitability. The third part is a case study where the support components applicability at targeting the key factors are evaluated, and suggestions for further improvements and testing of the support is suggested.  Further, using Design Research Methodology, the methods used to develop support in this thesis are presented to easily be replicated by other researchers to aid them in developing support for other industries and circumstances. The suitability of the developed support was tested using the principles of an initial DS-II. The developed support proved very useful for the investigated case, and with its conditions, the application evaluation was considered a partial success. Two key factors were successfully improved and indicated that the intended support is ready for a comprehensive DS-II. A third support component needs more work to provide the intended support fully. Therefore a second  PS iteration is recommended before a comprehensive DS-II is done to increase its value.

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