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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.
41

Food-based strategies to enhance iron and zinc bioavailability of complementary foods consumed by young children in Ethiopia / Voies alimentaires d’amélioration de la biodisponibilité du fer et du zinc dans les aliments de complément consommés par les jeunes enfants en Ethiopie

Baye Yimam, Kaleab 05 April 2013 (has links)
Voies alimentaires d'amélioration de la biodisponibilité du fer et du zinc dans les aliments de complément consommés par les jeunes enfants en Ethiopie. Le retard de croissance et les carences en micronutriments sont largement répandus dans les pays en développement tels que l'Ethiopie et atteignent un pic pendant la période d'alimentation complémentaire. L'adéquation des pratiques d'alimentation complémentaire du jeune enfant a été évaluée par rappel de 24h auprès de 76 ménages dans la région nord du Wollo, au nord de l'Ethiopie. Plusieurs pratiques d'alimentation n'étaient pas en accord avec les recommandations internationales WHO/PAHO. Les aliments les plus fréquemment consommés étaient l'injera –une sorte de galette à base de céréales fermentées- accompagnée de sauces à base de légumineuses, et le pain. Les procédés de transformation traditionnels de ces aliments ont été observés sur le terrain. Différents mélanges de céréales étaient utilisés pour la préparation de l'injera. Le type de mélange conditionne la cinétique de fermentation, qui à son tour, affecte l'hydrolyse de l'acide phytique. Même lorsque la dégradation de l'acide phytique était supérieure à 95%, la bioaccessibilité du fer et le pourcentage d'absorption calculé par algorithme n'étaient pas améliorés, alors que les ratios molaires phytate:Fe étaient optimaux (<0.4). D'autres inhibiteurs d'absorption semblent jouer un rôle important. A cet égard, les effets relatifs des phytates, polyphénols et fibres sur la bioaccessibilité du fer ont été évalués par une approche mécanistique utilisant des enzymes exogènes. Dans les farines utilisées pour la préparation de l'injera, la déphytinisation suivie de l'hydrolyse des fibres et/ou l'oxydation des polyphénols permet une augmentation de la bioaccessibilité du fer plus importante que la seule déphytinisation. La réponse aux traitements enzymatiques ainsi que l'importance relative des différents inhibiteurs d'absorption étaient dépendantes de la matrice alimentaire. L'optimisation des procédés traditionnels de transformation en vue de favoriser la dégradation des phytates, des polyphénols chélateurs de fer et des fibres pourrait améliorer significativement la biodisponibilité du fer dans les injeras. Des interventions visant à promouvoir les bonnes pratiques d'alimentation complémentaires recommandées par l'OMS sont nécessaires dans les régions enquêtées. Mots-clés: Phytate, polyphénols, fibres, altitude, micronutriments, bioaccessibilité / Food-based strategies to enhance iron and zinc bioavailability of complementary foods consumed by young children in EthiopiaStunting and micronutrient deficiencies are widespread in developing countries like Ethiopia and reach their peak during the period of complementary feeding. The adequacy of complementary feeding practices of young children in north Wollo, northern Ethiopia was evaluated in 76 households using two 24h recalls. Several feeding practices were not in accordance with WHO/PAHO recommendations. The most frequently consumed foods were legume-based stews, bread, and injera- a fermented cereal-based pancake. Traditional processing of these foods was observed in-field. Different cereal blends were used in injera preparation and this influenced the fermentation kinetics which in turn affected phytic acid hydrolysis. Even when phytic acid degradation was >95%, iron bioaccessibility and algorithm predicted absorption were not improved, despite ideal phytate:Fe molar ratios (<0.4). This suggested an important role of other absorption inhibitors. In this regard, the relative effect of phytate, polyphenols, and fibers on iron bioaccessibility was evaluated by making use of a mechanistic approach that involved the application of exogenous enzymes. In injera flours, dephytinization followed by hydrolysis of fibers and, or oxidation of polyphenols, resulted in higher iron bioaccessibility than dephytinization alone. The relative importance of mineral absorption inhibitors as well as the response to enzymatic treatments was dependent on the food matrix. If possible, optimization of household food processing for greater decrease in phytate, iron-binding polyphenols and fibers may be needed to significantly improve iron bioavailability in injeras. Interventions promoting the WHO guiding principles for complementary feeding practices and behaviors are recommended. Keywords: Phytate, polyphenols, fibers, altitude, micronutrients, bioaccessibility
42

Rétention et biodisponibilité du fer et du zinc au cours des procédés de préparation des plats traditionnels à base de céréales locales ou biofortifiées, consommés par les jeunes enfants au Burkina Faso / Retention and bioavailability of iron and zinc during processing of traditional dishes prepared from local and biofortified cereals and consumed by young children in Burkina Faso

Hama, Fatoumata 11 May 2012 (has links)
Dans un contexte où les carences en micronutriments constituent un problème majeur de santé publique touchant particulièrement les jeunes enfants, l'étude de la rétention et de la biodisponibilité du fer et du zinc dans les plats les plus fréquemment consommés peut constituer une stratégie de lutte contre les carences en ces minéraux. Une enquête de consommation alimentaire par pesées auprès de 630 enfants de 6 à 36 mois au Burkina Faso a permis de dégager les principales caractéristiques de l'alimentation de complément des jeunes enfants. Les résultats mettent en évidence une couverture des apports recommandés en fer et en zinc très faible, des apports élevés en fibres et en phytates. Le jour de l'enquête, plus de 90% des enfants avaient consommé du mil, du sorgho ou du maïs, essentiellement sous forme de tô, une pâte très consistante, de bouillie ou de galettes. Des suivis de préparation de ces plats dans les ménages ont permis d'identifier les principales opérations unitaires susceptibles d'avoir un effet sur les teneurs en fer et en zinc et leur biodisponibilité. Le décorticage traditionnel, manuel ou mécanique, entraine d'importantes pertes en fer (50% dans le mil pour 10% de perte de MS) et en zinc (23% dans le sorgho pour 7% de perte de MS). Les variétés biofortifiées présentent un comportement similaire, mais permettent tout de même une amélioration significative du rapport molaire phytate/zinc. La mouture, lorsqu'elle est réalisée à l'aide d'un moulin à meules, entraine une contamination en fer, allant jusqu'à tripler la teneur en fer initiale des grains. Mais la bioaccessibilité de ce fer est extrêmement faible. L'acceptabilité des variétés de mil biofortifiées, testées sur différents plats, reste inférieure à celle de la variété locale. L'amélioration des procédés combinée à l'utilisation de variétés biofortifiées pourrait être promue afin de contribuer à la lutte contre les carences en fer et zinc. / In contexts where micronutrient deficiencies are a major public health concern, the improvement of the retention and bioavailability of iron and zinc in dishes frequently consumed by young children could be part of a food-based strategy to combat these deficiencies. A food consumption survey using weighing records was carried out on 630 children from 6 to 36 months in Burkina Faso. This permitted to highlight the main characteristics of the children diet. Iron and zinc intakes were far below the recommended intakes. High fibre and phytate intakes were also observed. More than 90% of the young children consumed millet, sorghum or maize in the day of the survey. A detailed monitoring of the traditional processing of the cereal dishes permitted the identification of the main unit operations that could have an effect on iron and zinc content and bioavailability. Important losses in iron content (50% in millet for 10% DM loss) and zinc (23% in sorghum for 7% DM loss) were observed after traditional dehulling, either manual or mechanical. Biofortified varieties showed similar behaviour but their phytate/zinc molar ratio was still improved. During milling in local mill with grindstones, iron contamination occurred, and tripled the initial iron content. But the bioaccessibility of this contaminant iron was very low. The acceptability of the biofortified varieties of millet, tested on various dishes, was lower than that of the local variety. The improvement of the processing methods combined with the use of biofortified varieties could be advantageously promoted to contribute to alleviate iron and zinc deficiencies.
43

Improving corn and soybean yield through fertility and weed management practices

Mueller, Nathan D. January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Dorivar Ruiz Diaz / Winter annual weeds (WAW) could affect nitrogen supply for corn production. The objectives of first study were to determine the diversity and abundance of WAW and to evaluate the effect of delaying herbicide applications on nitrogen supply and no-till corn response. Research was conducted in 2010 and 2011 at 14 sites in eastern Kansas. A factorial arrangement of three herbicide application dates (Nov.-Mar., April, and May) and five N rates were used. The three most abundant WAW across sites were henbit, purslane speedwell, and horseweed. Delaying herbicide application until April significantly reduced early corn N uptake by 52 mg N plant-1, chlorophyll meter readings at silking by 3.4%, and grain yield by 0.48 Mg ha-1 across sites. An additional 16 to 17 kg N ha-1 was needed to maintain yield if herbicide application was delayed until April. Starter and foliar micronutrient fertilization can potentially increase corn and soybean yield. The objectives of the second study were to evaluate crop response from combinations of starter and foliar fertilizers that contain N-P-K mixtures with and without a blend of micronutrients at four sites for each crop under irrigated conditions. No early corn growth or yield increase was attributed to application of micronutrients (Fe, Mn, Zn, Cu, and B) beyond what was achieved with N-P-K starter fertilization. There was an increase in soybean height (8 cm) and yield (293 kg ha-1) with starter fertilizer containing N-P-K plus micronutrients over the control. No increase in corn or soybean yield was obtained with foliar fertilization. The objective of the third study was to compare soil mobility and changes in soybean nutrient concentration in the leaf and seed from Mn and Zn sources (EDTA and oxysulfate) at two sites. Zinc sources were more mobile in the soil. Both Zn sources increased seed Zn concentration. Manganese oxysulfate increased seed Mn concentration. However, soybean trifoliolate leaf and seed Mn concentration decreased with soil-applied Na2EDTA and MnEDTA. This response was attributed to formation of FeEDTA and increased Fe supply that reduced root Mn absorption. Manganese EDTA is not recommended for soil application.
44

Evaluation of secondary and micronutrients in Kansas

Gutierrez Rodriguez, Miriam Nicole January 1900 (has links)
Master of Science / Department of Agronomy / Dorivar Ruiz Diaz / The limitation of an essential nutrient for plant growth can affect crop yield. Research has been focused mainly on macronutrients, nevertheless micronutrients are equally important. This thesis is divided into three studies, which had the purpose of assessing frequent questions that producers have about micronutrient fertilizers and their effect on several crops in Kansas. The objective of the first study was to summarize and analyze results from studies since 1962 until 2015 to verify responses to zinc (Zn) and sulfur (S) fertilization in corn (Zea mays), sorghum (Sorghum bicolor (L.) Moench), wheat (Triticum aestivum) and soybean (Glycine max (L.) Merr). The treatments evaluated consisted of fertilizer Zn or S application versus their respective unfertilized treatments. Zinc fertilization significantly increased corn yield; no significant response was found for sorghum, wheat and soybean. Sulfur fertilization did not increase yields on corn and wheat. The objectives of the second study were: (i) to evaluate soybean response to S and micronutrients boron (B), copper (Cu), manganese (Mn), and Zn fertilizer application and to assess soil test and soybean seed and tissue nutrient concentration with fertilization. Treatments consisted of an unfertilized control, micronutrient fertilizer as individual nutrient for B, Cu, Mn, S and Zn applied broadcast pre-plant, in addition to a blend of these nutrients using two different placements (broadcast and band). Secondary and micronutrient fertilization showed no significant effect on soybean yield at any of the ten locations. Zinc fertilization showed significant effects on soybean tissue and seed Zn concentration. The objective of the third study was to evaluate soybean tissue nutrient response to micronutrient fertilizers in field strips with high variability in soil properties in the area evaluated. The study consisted of two strips (with and without fertilizer) and replicated three times. The treatment with fertilizer included a blend of Cu, Mn and Zn at a rate of 11.2 kg ha⁻¹ and B at a rate of 2.8 kg ha⁻¹. Initial soil tests B, Cu, Mn and Zn were not good indicators of soybean tissue response. Within-field variability of soybean Zn and B tissue content were affected by soil pH and organic matter; and these factors may be used to help explain field variability in plant availability. The micronutrient blend treatment showed higher tissue Zn and B values compared to the control. When pH ranged from 5.5 to 7.6, B in soybean tissue was higher on the control than the micronutrient blend treatment. Copper concentration in soybean tissue did not show significant difference between treatments at any location, regardless of pH and organic matter levels.
45

Dietní systém z pohledu makronutrientů a mikronutrientů / Diet system from the perspective of macronutrients and micronutrients

Kočí, Kateřina January 2019 (has links)
The aim of the thesis: The aim of this observational study of non-interventional nature, was to map the representation of macronutrients and selected micronutrients in the menus served to patients suffering of gastritis as well as other nutrition diets. Additionally, to research and review the dietary systems in healthcare facilities of the Czech Republic, in order to compare the obtained data with recommended nutritional intakes, as recommended/stated in the issue "Reference Values for Nutrition Intake". The purpose is to evaluate, whether both types of the diets follow the recommended values. Methodology: The source of the data for this thesis were the menus distributed to patients following the recommendations of norms related to gastritis and rational nutrition diets for the period of one week. By applying the "Nutriservis PROFESIONAL software" the content of studied macronutrients and selected micronutrients in the daily menus was determined in the collected data. Results: Ten selected healthcare facilities from six regions in the Czech Republic participated in the research. It was determined from the obtained data, that insufficient presence of fiber, wrong balance, as well as the amount of unsaturated and saturated fatty acids along with high amount of sodium were the key malpractices,...
46

Eficiência agronômica de fontes de fósforo e micronutrientes sobre a produtividade e qualidade tecnológica em soqueira de cana-de-açúcar / Agronomical efficiency of phosphorus sources and micronutrients over productivity and technological quality in ratoon sugar cane

Peres, Celso Eduardo Bonafé 25 March 2014 (has links)
A nutrição mineral representa um dos principais fatores de produção na cultura da cana-de-açúcar, tendo impacto direto na produtividade, na qualidade, e nos custos de produção. A expansão da cultura sobre área de baixa fertilidade natural ou ainda em áreas tradicionais de cultivo com evidente esgotamento dos recursos, reforça a necessidade da aplicação de fertilizantes na recuperação da produtividade, principalmente em áreas de soqueira de cana. O fósforo é um elemento chave nesse processo dada a intensidade das reações de adsorção e fixação, que o tornam pouco disponível para a cultura. Além disso o fato de ser normalmente aplicado na reforma do canavial, não garante o correto fornecimento do mesmo nos ciclos consecutivos de soca. Já os micronutrientes representam um desafio, uma vez que mesmo em áreas deficientes, as resposta não são conclusivas. Neste contexto, o objetivo deste trabalho foi avaliar a eficiência de fertilizantes fosfatos aplicados no solo e micronutrientes aplicados via foliar sobre a produtividade e qualidade tecnológica em soqueira de cana-de-açúcar. Para tanto, foi instalado um experimento no município de Porto Ferreira(SP) na Usina Ferrari S/A, em dezembro de 2010, sob Latossolo Vermelho-Amarelo Distrófico de textura média, com a variedade RB - 85 7515, 3ª soca em área colhida mecanicamente e sem queima. O delineamento experimental utilizado foi de blocos casualizados com parcelas subdivididas. Nas parcelas foram aplicados os tratamentos principais correspondendo às fontes de fósforo: T1 - Controle (sem adubação); T2 - 495 kg ha-1 da formulação 21-00-14 (nitrato de amônio + cloreto de potássio); T3 - 495 kg ha-1 da formulação 21-07-14 (nitrato de amônio +superfosfato triplo + cloreto de potássio); e T4 - 495 kg ha-1 da formulação 21-07-14 (Polifosfatos + ortofosfatos -YaraMila&trade;).Nas subparcelas foram aplicados os tratamentos secundários, compostos pela aplicação ou não de micronutrientes via foliar. As doses e fontes utilizadas formam: Zn= 778g ha-1 (óxidos); B= 150 g ha-1 (Borato de monoetalomina); Cu= 110g ha-1 (óxidos); Mn= 331g ha-1 (Carbonato de Mn); e Mo= 52g ha-1 (Molibdato de sódio). Após a colheita da cana (Agosto de 2011) pode-se constatar que a produtividade média da soqueira de cana-de-açúcar respondeu significativamente a aplicação de N-K, N-P-K e as diferentes fontes de P. A utilização de 104 kg ha-1 de N na forma de nitrato de amônio e 70 kg ha-1 de K2O na forma de cloreto de potássio proporcionam incremento médio de produtividade de 4 t de ha-1 em relação ao controle sem adubação. Em relação ao fósforo, a utilização de 35 kg ha-1 de P2O5 promoveu um ganho médio de produtividade de 12,6 t ha-1 em comparação ao controle sem adubação. Considerando as fontes, o fertilizante 21-07-14 YaraMila contendo polifosfatos em sua formulação proporcionou produtividade média superior em de 4 t ha-1 em relação ao fertilizante 21-07-14 contento como fonte de P o superfosfato triplo. A utilização de micronutrientes nas doses, fontes e forma de aplicação testadas, não proporcionou ganho produtivo significativo em relação a área sem aplicação. Com respeito as variáveis tecnológicas, utilização de fertilizantes contendo N-K e N-P-K e a utilização de micronutrientes aplicados via foliar nas doses e fontes testadas não alterou significativamente os parâmetros, pureza, pol, fibra e ART. / The mineral nutrition is one of the main production factors in the sugar cane culture having a direct impact in productivity, quality, and in production costs. The expansion of culture in low natural fertility area and traditional area with evident source depletion reinforce the necessity of fertilizers application in the productivity recovering, especially in areas of brass knuckles. The phosphorus is a key element in this process due to the intensity of the adsorption and fixation reactions that make it less available for the culture. Besides that, the fact that phosphorus is normally applied in the sugar cane area reform does not guarantee the correct supply of this element in the consecutives cycles of ratoon. On the other hand, the micronutrients present a challenge, knowing that even in deficient areas, the answers are not conclusive. In this context, the main of this work was to evaluate the efficiency of phosphate fertilizers applied in the soil and micronutrients applied via foliar over the productivity and technological quality in ratoon sugar cane. For that purpose, it was installed an experiment in a town called Porto Ferreira (SP), in the Plant Ferrari S/A, in December 2010, under Oxisol Distrophic medium texture with the variety RB - 857515, in the 3ª ratoon sugar cane mechanically harvested and unburned area. The experimental design used was the one with randomized blocks with split plots. In these plots, the main treatments were applied, each one corresponding to the sources of phosphorous: T1- Control (without fertilizer); T2- 495 kg ha-1 from formulation 21-07-14 (ammonium nitrate + triple superphosphate + potassium chloride); and T4- 495 kg ha-1 from formulation 21-07-14 (Polyphosphates + orthophosphates - YaraMila&trade;). In the subplots, the secondary treatments were applied, composed by the application or not of the micronutrients via foliar. The doses and sources used were: Zn= 778g ha-1 (oxides); B= 150 g ha-1 (Borate monoetalomine); Cu= 110g ha-1 (oxides); Mn= 331g ha-1 (Mn Carbonate); and Mo= 52 g ha-1 (Sodium molybdate). After harvesting the sugar cane (August 2011), it could be concluded that the average productivity of the brass knuckles had a significant response to the application of N-K, N-P-K and to the different sources of P. The use of 104 kg ha-1 of N in the form of ammonium nitrate and 70 kg ha-1 of K2O in the form of potassium chloride made possible an average increasing in productivity of 4 t of ha-1 when comparing with the control without fertilizer. Considering the sources, the fertilizer 21-07-14 YaraMila containing polyphosphates in its formulation promoted superior average productivity of 4 t ha-1 when compared to the fertilizer 21-07-14, which contained triple superphosphate as P source. The use of micronutrients in the doses, sources and application forms tested didn\'t promote significant production gain in relation to the area without application. About the technological varieties, the use of fertilizers containing N-K and N-P-K and the use of micronutrients applied via foliar in the tested doses and sources didn\'t change significantly the parameters, purity, pol, fiber and ATR.
47

Enriquecimento de sementes de soja com cobalto e molibdênio / Soybean seed enrichment with cobalt and molybdenum

Gruberger, Gabriel Asa Corrêa 20 January 2017 (has links)
A aplicação de cobalto (Co) e molibdênio (Mo) diretamente às sementes de soja (Glycine max (L.) Merrill) é uma prática comum no cultivo dessa leguminosa no Brasil. Porém, esta técnica apresenta limitações, provocando fitotoxicidade na planta, interferindo na absorção de ferro (Fe) pelas raízes, diminuindo a população das bactérias fixadoras de nitrogênio do gênero Bradyrhizobium nas sementes e aumentando uma etapa no pré-plantio. Uma maneira de contornar essas limitações seria a utilização de sementes enriquecidas com Co e Mo. Contudo, há carência de pesquisas com a finalidade de aumentar o teor de Co nas sementes de soja, haja vista que o potencial de enriquecimento com Mo já foi demonstrado. O objetivo do presente projeto foi determinar a viabilidade de enriquecimento de sementes de soja com Co e Mo e relacionar o enriquecimento ao potencial fisiológico das sementes. O projeto foi composto por dois experimentos. O primeiro experimento foi desenvolvido em casa de vegetação, localizada no Centro de Energia Nuclear na Agricultura (CENA/USP), em Piracicaba (SP). O delineamento experimental utilizado foi o de blocos casualizados, com três repetições, em esquema fatorial (4x2)+1 e (4x2)+2, composto por 4 doses de Co, 2 variedades de soja, 2 formas de aplicação e o controle sem Co e Mo. Plantas de duas variedades de soja (uma de ciclo longo e outra precoce) foram cultivadas em vasos contendo 3 dm3 de amostra de solo arenoso. No estádio fenológico de desenvolvimento R5.4 (início do enchimento das sementes), aplicou-se, via solo e via folha, os seguintes tratamentos de Co + Mo (g ha-1): 0+800, 10+800, 20+800 e 30+800, além de um controle sem Co e Mo. O segundo experimento foi conduzido em campo, no Centro de Pesquisa Geraldo Schultz, em Iracemápolis (SP). O delineamento experimental foi em blocos casualizados, com 6 repetições. As doses de Co + Mo e a variedade de soja utilizadas foram idênticas às do experimento realizado em casa de vegetação, no entanto, a aplicação em campo foi exclusivamente via foliar e a variedade utilizada foi a de ciclo longo. Foram avaliados os teores de Co e Mo no solo, folhas e sementes; os índices de clorofila (IC), de flavonóides (IF) e de balanço de nitrogênio (NBI); a germinação; e o vigor das sementes enriquecidas, utilizando o método de Envelhecimento Acelerado e a análise computadorizada de plântulas, com o auxílio do software SVIS® (Seed Vigor Imaging System). Foi verificada viabilidade no enriquecimento de sementes de soja com Co e Mo, sendo que a variedade mais precoce apresentou maiores teores de Co e Mo nas sementes. O enriquecimento das sementes com Co interferiu positivamente no vigor das sementes, obtendo-se melhor desempenho com a aplicação de 20 g ha-1 de Co. O enriquecimento com Mo, no entanto, não alterou o vigor das sementes. A aplicação foliar proporcionou maiores teores de Co nas sementes, em comparação à aplicação via solo. A aplicação via solo, porém, proporcionou maiores teores de Mo nas sementes em comparação à aplicação via foliar / The application of cobalt (Co) and molybdenum (Mo) directly to soybean (Glycine max (L.) Merrill) seeds is a common practice in Brazil. However, this technique presents limitations, provoking phytotoxicity, interfering in the absorption of iron by roots, decreasing the population of nitrogen-fixing bacteria of the genus Bradyrhizobium in the seeds, and requiring an additional step in the pre-planting stage. One way to overcome these limitations would be to use seeds enriched with Co and Mo. However, there is a lack of research aimed at increasing Co content in soybean seeds, since the potential for enrichment with Mo has already been established. The aim of this study is to determine the feasibility of enriching soybean seeds with both Co and Mo and to relate the enrichment to increase in the physiological quality of the seeds. The project consists of two experiments. The first experiment was carried out under greenhouse conditions, located at the Center for Nuclear Energy in Agriculture (CENA / USP), in Piracicaba (SP). The experimental design was completely randomized, with three replications, in a factorial scheme (4x2)+1 and (4x2)+2 of which 4 Co doses, 2 varieties, 2 application modes and the control without Co and Mo. Plants of two soybean varieties (one long and one precocious cycle) were grown in pots containing 3 dm3 of sandy soil. The following treatments of Co and Mo (g ha-1) were applied: 0 + 800, 10 + 800, 20 + 800, 30 + 800, via leaf and soil, after planting, at the R5.4 phenological stage of development. The second experiment was conducted in the field, at Geraldo Schultz research center, in Iracemápolis (SP), using only the long cycle genotype. The doses of Co + Mo used were identical to those of the greenhouse experiment; however, the application was exclusively via leaf. The experimental design was in randomized blocks with 6 replications. Co and Mo content in soil, leaves and seeds as well as indices for chlorophyll (IC), flavonoids (IF), nitrogen balance (NBI), germination and vigor of enriched seeds were evaluated by means of Accelerated Aging and computer analysis of seedlings by means of SVIS® (Seed Vigor Imaging System) software. Enrichment of soybean seeds by means Co and Mo proved to be viable, with the earlier varieties having a higher Co and Mo content in the seeds. Seed vigor was positively influenced by Co enrichment; best results were obtained with application of 20 g ha-1 of Co. Enrichment with Mo, however, had no influence on seed vigor. Application via leaf resulted in higher levels of Co in seeds compared to application carried out via soil. On the other hand, application via soil resulted in higher levels of Mo in seeds in comparison to application carried out via leaf
48

Disponibilidade de energia e nutrientes nos domicilios de famílias das regiões metropolitanas de Curitiba e Porto Alegre. / Energy and nutrients availability in dwelling families from Curitiba and Porto Alegre metropolitan areas.

Bleil, Rozane Aparecida Toso 20 September 2004 (has links)
O consumo de alimentos é influenciado, entre outros fatores, pelo processo de urbanização, as políticas agrícolas, a disponibilidade de alimentos, a distribuição de renda, o processamento inadequado, tradições culturais e a propaganda. Em decorrência de desequilíbrios nos elos existentes entre essas variáveis, podem ser observadas, freqüentemente, conseqüências negativas à saúde da população, tais como a desnutrição, obesidade e doenças crônicas. O presente trabalho foi realizado, tendo por base os dados da Pesquisa de Orçamentos Familiares (POF-1995/1996), relativos à amostra da população residente nas regiões metropolitanas de Curitiba e Porto Alegre, pertencentes à Região Sul do Brasil. Os objetivos foram analisar, no âmbito dos domicílios, a disponibilidade de energia e a participação dos macronutrientes no Valor Energético Total - VET; analisar a oferta de proteínas quanto à sua origem (animal ou vegetal); analisar a disponibilidade de fibras, colesterol, vitaminas e minerais nos domicílios da referida população; analisar a disponibilidade de alimentos quanto a sua origem (industrializados e in natura) e também a participação dos grupos alimentares no VET diário das famílias. Para os cálculos nutricionais foi utilizado o software Virtual Nutri (Phillippi, 1996). Adotou-se como parâmetro, as recomendações de energia, macro e micronutrientes, os valores preconizados pela National Academy of Sciences (2003). Os resultados mostram que a disponibilidade de energia e macronutrientes para estes grupos populacionais pode ser considerada adequada. Por outro lado, a participação da proteína de origem animal revelase elevada para a totalidade das famílias. Em relação ao colesterol os resultados apresentam-se abaixo dos valores preconizados. Ressalva-se que a presente pesquisa não avaliou o consumo de alimentos fora do domicílio. Considerando a disponibilidade de fibras para as famílias da amostra, infere-se que a mesma é insuficiente. Em relação aos micronutrientes, observa-se uma baixa disponibilidade, dos seguintes nutrientes: ácido fólico, niacina, vitamina B12, cálcio, ferro, zinco, magnésio e selênio. Em relação aos grupos alimentares, merece destaque a maior participação do grupo das leguminosas, especialmente o feijão, no VET (disponível nos domicílios) das famílias mais pobres. Por outro lado, observa-se aumento na disponibilidade do grupo das carnes e embutidos e do leite e derivados, conforme ocorre incremento da renda, o que ressalta a influência desta na aquisição de alimentos. Não é identificada diferença expressiva na participação de hortaliças no VET, quando se considera concomitante, as famílias dos diferentes estratos de renda e as duas regiões metropolitanas. Por outro lado, a participação das frutas mostra tendência crescente, conforme aumenta a renda. Há um predomínio de produtos industrializados no VET, quando se considera a totalidade das famílias integrantes da pesquisa. A renda e os hábitos culturais parecem exercer influência decisiva nos hábitos alimentares da população observada. Face ao exposto é fundamental que se busquem estratégias, que adotadas em curto espaço de tempo, contribuam de forma decisiva para a melhoria dos hábitos e o padrão de consumo alimentar da referida população. / The food consumption is influenced, among other factors, by the process of urbanization, agricultural policies, food availability, income distribution, adequate processing, feeding habits and marketing. In the course of this interaction, negative consequences may be observed in the state of health, such as malnutrition, obesity and chronic illnesses. The present study was accomplished using the Family Budgetary Survey (FBS-1995/1996) data base, related to the metropolitan areas of Curitiba and Porto Alegre -southern Brazil. The objectives were to analyze the families accessibility to energy and the participation of macronutrients in the Total Calorie Value-TCV available in the domicile; to differentiate the protein origin (animal or vegetal); to estimate the amounts of dietary fiber, cholesterol, vitamins, and minerals at the household’s disposal in the referred population; to determine the food accessibility according to the extent of transformation (manufactured or in natura) and also, the participation of each food group at the families’ disposal, according to the daily TCV. The software Virtual Nutri (Phillippi, 1996) was used to calculate nutrient availability. Energy, macro and micronutrient recommendations by the National Academy of Sciences (2001) were adopted as parameters. The results showed that the energy and macronutrients at the disposal of these population groups may be considered adequate. On the other hand, the study revealed elevated participation of animal protein for the totality of families. Cholesterol, however, appeared to be present at amounts lower than recommended, notwithstanding the fact that this research did not take into account the food consumed outside the domicile. Considering the dietary fiber at the disposal of these families, we can infer it was insufficient. In relation to micronutrients, we observed a low availability, especially for folic acid, niacin, vitamin B12, calcium, iron, zinc, magnesium and selenium. In relation to the food groups, the participation of legumes, especially beans, on the TCV of the household of the poorest families was outstanding. On the other hand, we observed an increase in the access to meat and poultry, and milk and milk products, concordant with the rising of income, which reinforces the influence of income on food acquisition. The participation of potherbs greens did not present any meaningful difference when the income stratum and metropolitan area were considered. The participation of fruits appeared with an increasing tendency, in relation to income. There was yet the predominance of manufactured food products on the TCV for the totality of families surveyed. It may be concluded that both income and cultural habits seem to exert decisive influence on the food habits of this population. Thus, it is fundamental to search for alternatives in order to improve the habits and consumption patterns of the referred population, independent of their socioeconomical or cultural backgrounds.
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Crescimento e marcha de absorção de nutrientes de bananeira (Musa sp. AAA), 'Grande Naine' no primeiro ciclo de produção / Growth and absorption nutrients march of banana tree (Muse sp. AAA), `Grande Naine' in the first production cycle

Araujo, João Paulo Campos de 02 April 2008 (has links)
O presente trabalho consistiu na determinação da marcha de absorção de macro e micronutrientes pela bananeira (Musa spp), cultivar Grande Naine durante o primeiro ciclo de produção. Foram amostrados os rizomas, pseudocaules, folhas e posteriormente inflorescências, mensalmente durante o ciclo da cultura, que nas condições do ensaio foi de dezesseis meses. Foram avaliadas as dimensões (diâmetro e comprimento) dos rizomas, altura das plantas, número de folhas, e massas frescas e secas desses órgãos. Após o oitavo mês de cultivo houve a necessidade de se obter sub-amostras das partes analisadas, operação essa realizada manualmente, uma vez que o volume amostrado excedia a capacidade da estufa de secagem. As amostras foram levadas para estufa de circulação forçada de ar até atingirem massas constantes. As análises dos teores de macro e micronutrientes seguiram o método preconizado por Sarruge ; Haag (1974). As plantas apresentaram acúmulo de massa seca inicialmente lento, tendo seu crescimento acentuado a partir do décimo mês após o transplantio. A ordem decrescente da extração dos macronutrientes pela planta foi: K>N>Ca>Mg>P>S, e a razão de extração foi: 89K: 17N: 10Ca: 6Mg: 2P: 1S. A ordem decrescente da extração de micronutrientes foi: Fe>Mn>Cu>Zn>B, e a razão de extração foi: 41 Fe: 10Mn: 3Cu: 2Zn: 1B. As equações de regressão que mais se adequaram para os rizomas, pseudocaule e folhas foram os modelos exponenciais, para as inflorescências, o modelo que mais se adequou foi a equação polinomial de terceiro grau. A reciclagem de nutrientes, a partir de um manejo adequado de órgãos, bem como a sua exportação junto com a colheita, deve ser levada em consideração em qualquer programa de adubação da bananeira. / This work consisted of the determination of the macro and micronutrients absorption march for the banana tree (Muse spp), cultivar Grande Naine during the first production cycle. Samples of rhizomes, pseudostem, leafs and later inflorescence, were taken monthly during the cycle of the culture, the cycle in the conditions of the study takes sixteen months. The rhizomes dimensions (diameter and length) had been evaluated, the plants height, leaf number, determination the fresh and dry masses of these parties. After the eighth month of start had the necessity of getting sub-samples of the analyzed parts, this operation carried manually, because the volume of the samples exceeded the capacity of the drying greenhouse. The samples had been taken for greenhouse until reaching constant masses. The macro and micronutrients analyses were made by Sarruge ; Haag (1974) method. The plants had presented initially slow accumulation of dry mass, growing accented from the tenth month after the transplantation. The decreasing order of the extraction of macronutrients was K>N>Ca>Mg>P>S and the extraction reason was 89K: 17N: 10Ca: 6Mg: 2P: 1S. The decreasing order of the extraction of micronutrients was Fe>Mn>Cu>Zn>B and the extraction reason was 41 Fe: 10Mn: 3Cu: 2Zn: 1B. The regression equations that if had more adjusted for rhizomes, pseudostem, and leafs had been the exponentials, for the inflorescence, the model that adjusted was the third degree polynomial equation. The nutrients recycling, from an adequate handling of agencies, as well as its exportation with the harvest, must be taken in consideration in any program of fertilization of the banana tree.
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Crescimento, nutrição e fitossanidade de povoamentos de eucalipto fertilizados com boro, cobre e zinco na presença e ausência de resíduos florestais / Growth, nutrition and phytosanity of eucalyptus stands fertilized with boron, copper and zinc in the presence and absence of forest residues

Masullo, Liamara Santos 22 January 2018 (has links)
O aumento da demanda por produtos florestais impulsionou o crescimento das áreas plantadas mundiais, passando de 167 milhões de hectares em 1990 para 280 milhões em 2015. No setor brasileiro de florestas plantadas, as espécies de Eucalyptus possuem grande representatividade, sendo responsáveis pelo suprimento de 90 % da madeira produzida no país. As áreas em que os novos povoamentos de eucalipto estão sendo estabelecidos são caracterizadas por condições climáticas pouco favoráveis e pela baixa fertilidade química do solo. O suprimento nutricional apresenta forte influência sobre a produtividade e contribui para prevenção contra estresses bióticos e abióticos. A deficiência de micronutrientes é uma realidade emergente, sendo o B, o Cu e o Zn os nutrientes mais problemáticos para a cultura em solos do Cerrado. Estes nutrientes estão associados às cadeias metabólicas de produção de lignina, de fenóis e de fitoalexinas como cofatores e ativadores enzimáticos. Estas moléculas, além de participarem da integridade funcional e estrutural de membranas e de outros componentes celulares das plantas, cumprem a função de aumentar a resistência das plantas ao ataque de patógenos. Assim, foram estudados os efeitos da omissão e da aplicação de micronutrientes B, Cu e Zn associado à manutenção ou à remoção de resíduos florestais. Foram avaliados os aspectos nutricionais das árvores e suas relações com o volume de madeira produzido e com a suscetibilidade ao ataque da ferrugem do eucalipto (Puccinia psidii). A remoção dos resíduos florestais da colheita apresentou pouca influência sobre os teores disponíveis de B, Cu e Zn no solo. A omissão de B e de Zn influenciou os teores disponíveis destes nutrientes no solo, contudo apenas os baixos teores de B se refletiram na nutrição das árvores. No crescimento das árvores, o diâmetro à altura do peito teve redução aos 12 e aos 15 meses pós-plantio. Esta diferença foi encontrada entre os tratamentos com aplicação completa de nutrientes e com omissão de Zn. O tratamento com omissão de Zn apresentou o maior crescimento e, em geral, a maior concentração de macronutrientes e de micronutrientes foliares. O tratamento com omissão de Zn apresentou também a menor infestação e severidade do ataque por ferrugem, mostrando a importância da nutrição balanceada das árvores para o crescimento e para a proteção dos povoamentos florestais. / The increasing demand for forest products has promoted the growth of planted areas worldwide, from 167 million hectares in 1990 to 280 million in 2015. In the Brazilian planted forest sector, Eucalyptus species supply 90 % of the produced wood in the country. In general, eucalyptus stands are established in areas with unfavorable climatic conditions and low soil fertility. Mineral nutrition has an important influence on productivity and prevention against biotic and abiotic stresses. Micronutrient deficiency is an emerging reality, and B, Cu and Zn are the most problematic nutrients for eucalypt cultivation in soils of the Brazilian Cerrado. These nutrients are related to lignin, phenol and phytoalexin production pathways as cofactors and enzymatic activators. These molecules present relations with the resistance and the susceptibility of the plants to the pathogens attack, besides participating in the functional and structural integrity of membranes and other cellular constituents of plants. Thus, the omission effects were studied and application of B, Cu and Zn associated with the forest residues management. Trees nutrition and their relation with volume and susceptibility to eucalyptus rust (Puccinia psidii) were evaluated. The removal of forest residues from the harvest had little influence on the available levels of B, Cu and Zn in the soil. The omission of B and Zn influenced the availability of these nutrients in the soil; however, only low levels of B were reflected in trees nutrition. The diameter at breast height had a growth reduction at 12 and 15 months after planting. This difference was found between treatments with complete application of nutrients and with Zn omission. The treatment with Zn omission had the highest growth and, in general, the highest leaf concentration of macronutrients and micronutrients. The treatment with Zn omission also showed the lowest infestation and severity of eucalyptus rust. Thus, balanced mineral nutrition of trees favored growth and health of the forest stand.

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