The need to assess human exposures to foodborne and environmental carcinogens, particularly in populations at high risk for cancer and disease, has led to the development of chemical-specific biomarkers. Sensitive biomarkers for aflatoxin and polycyclic aromatic hydrocarbons (PAHs) have been useful in providing information on population exposure and reducing associated public health impacts. Aflatoxins are fungal metabolites found in a variety of foods. Among these toxins, aflatoxin B1 (AFB1) is the most predominant and hepatocarcinogenic. Acutely, AFB1 can cause disease and death, necessitating safe and effective intervention strategies. Inclusion of NovaSil (NS) clay in the diet represents a practical, sustainable approach. NS has been shown to prevent aflatoxicosis in multiple animal species by binding aflatoxins in the gastrointestinal tract, reducing toxin bioavailability. Co-exposure to PAHs, hazardous environmental contaminants, has been shown to increase the risk for hepatocellular carcinoma (HCC). Therefore, objectives of this research were to utilize biomarkers to assess aflatoxin and PAH exposures in susceptible populations in Ghana and the U.S. and to evaluate the safety and efficacy of NS intervention in Ghana (a population at risk for aflatoxicosis). After 3-month intervention with 3.0g NS/day, median aflatoxin M1 (an AFB1 metabolite) was significantly reduced (up to 58 percent) compared to the placebo group. Furthermore, no significant differences were found in levels of nutrient minerals between NS and placebo groups at baseline and 3-months suggesting NS can be used to effectively sorb AFB1 without affecting serum concentrations of important minerals. PAH biomarker results showed participants in Ghana were significantly exposed to high levels of PAHs based on the presence of 1-hydroxypyrene (1-OHP) in the majority of urines (98.9 percent). NS treatment had no effect on 1-OHP levels, further confirming the preferential binding of aflatoxins by NS. U.S. population data from a Hispanic community in Texas with an elevated incidence of HCC demonstrated a lower percentage and level of aflatoxin and PAH biomarkers. Aflatoxin M1 excretion, however, was associated with increased consumption of certain foods prone to aflatoxin contamination; thus, some individuals may be more vulnerable to exposure and associated interactions that increase the risk for HCC (e.g., PAHs or hepatitis infection).

Health benefits related to consumption of whole grains have been attributed in part to phytochemical and micronutrient composition. Understanding the composition, structure and distribution of these components in different cereal grains is of potential importance in aiding the selection of whole grains and their processed fractions for inclusion in the diet, and as ingredients in development of new food products. The aim of this research was to characterise the chemical components in the botanical fractions of yellow corn, barley, wheat. Manual separation, a tedious and laborious technique that yields pure fractions, suitable for compositional analysis, was used to separate whole grains into pericarp, aleurone layer, germ and endosperm fractions. Component identification and quantification of tissue components was accomplished by several techniques. The study also explored the possibility of using spectral characteristics fluorescence intensity values to provide rapid estimates of the concentrations and distribution of ferulic acid (FA), a major phenolic compound in cereal grains. While composition of phenolic acids and carotenoids was similar, the distribution was significantly different (P < 0.05) among cereal types and grain fractions. Phenolic acids were concentrated in pericarp and aleurone fractions, followed by the germ and the endosperm had the lowest levels. Yellow corn exhibited the highest values. Carotenoids, lutein and zeaxanthin were concentrated in the germ and aleurone layer of wheat and barley while in yellow corn it was in the endosperm and aleurone layer. This is the first study to report on carotenoid composition of aleurone fractions. Mineral elements, thiamine and niacin were higher in wheat aleurone than in purple barley and yellow corn aleurone layers. These findings suggest that yellow corn aleurone layers have potential as a functional food ingredient despite the low micronutrient content. A positive, significant correlation (r= 0.421, p < 0.0001) was found between fluorescence intensity values and ferulic acid concentration. Thus, fluorescence intensity profiles are a promising approach for rapid assessment of FA concentration in grain in-situ. This work has provided information that would act as a database for selection of cereal fractions and guide the miller to obtain grain fractions with enriched levels of phytochemicals and micronutrients. / February 2016

Thesis (MNutr (Human Nutrition))--Stellenbosch University, 2008. / Background Critical illness is associated with increased production of reactive oxygen species and oxidative stress, and low levels of most micronutrients with resultant diminished endogenous antioxidant defences. Micronutrient supplementation is thought to be beneficial to the critically ill patient by ameliorating oxidative stress and by improving clinical outcome. Objectives This systematic review assessed the effects of micronutrient supplementation on adults recovering from critical illness. Primary outcomes included clinical endpoints [mortality, infectious complications, length of intensive care unit and hospital stay (LICU and LOS)]. Secondary outcomes included descriptions of practice issues, micronutrient status, morbidity, course of the acute phase response and oxidative stress. Search strategy An electronic bibliographic database search was carried out, bibliographies of retrieved articles were reviewed and personal files searched to obtain additional citations. Databases were searched from inception until 29 February 2008. Selection criteria Randomized controlled trials (RCTs) of micronutrient supplementation (by any route) in adult critically ill patients, given in addition to their routine care, were included. Data collection and analysis Two authors independently extracted data and assessed trial quality. For the primary outcomes the random-effects model was used to estimate overall relative risk / mean difference and effect size due to the presence of study heterogeneity. Selected exploratory analyses were undertaken. Differences at the level of p<0.05 was considered to be statistically significant. The secondary outcomes were sparse and variably recorded such that this data was not formally aggregated. Main results Fifteen RCTs involving 1714 participants and 18 RCTs involving 1849 participants were included for the primary and secondary objectives respectively. The quality of the RCTs, as reported, was disappointing, particularly for allocation concealment. Fourteen trials (n=1468) of micronutrient supplementation showed a statistically significant reduction in overall mortality [relative risk (RR) 0.78, 95% confidence interval (CI) 0.67-0.90, I2=0%, p=0.0009]. An asymmetrical funnel plot necessitates caution when directly interpreting these results. Six RCTs (n=1194) indicated a statistically significant reduction in 28 day mortality (RR 0.75, 95% CI 0.63-0.88, I2=0%, p=0.0006) (symmetrical funnel plot). Micronutrient supplementation in this systematic review was not associated with a reduction in infectious complications, LICU or LOS. In sub-group analyses, single nutrients were associated with borderline statistical significance (RR 0.82, 95% CI 0.66-1.01, I2=0%, p=0.06) in terms of mortality, whist a sensitivity analysis of combined micronutrients indicated a significant reduction in mortality (RR 0.69, 95% CI 0.54-0.90, I2=2%, p= 0.006). This review did not find clear evidence that parenteral is superior to enteral administration in terms of clinical outcomes. The secondary outcomes confirmed that timing, duration and dosing are key factors to ensure optimal clinical benefit. Conclusion This review does suggest potential benefit of micronutrient supplementation in critically ill adults for some clinical outcomes (especially mortality), but also highlights that caution is warranted as nutrient interactions and risk of toxicity are not clearly defined in critical illness. More large multi-centre randomized trials are necessary to assess the effects of different types and doses of micronutrient supplementation in selected groups of patients with different types of critical illness.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aiming to develop studies relating laboratory spectroradiometry with macro and micronutrients contents of vegetative materials of forest populations of Eucalyptus grandis W Hill ex Maiden, of different ages, an experimental área was selected for the study at the Fundação Estadual de Pesquisas Agropecuárias FEPAGRO FLORESTAS, at Santa Maria, Rio Grande do Sul, Brazil. Departing from the purpose of studying the spectral behaviour, the specific objectives were: 1) to evaluate the leaves of E. grandis contents of macro and micronutrients, in the four climatic seasons, under differente types of soil managements; 2) to evaluate the leaves of E. grandis spectral behaviour including the waveband of 475 to 980ηm and approach the interaction between: climatic seasonal periods, different soil managements and the cardinal points locations of the sampled trees; 3) evaluate the nutritional status of E. grandis young trees leaves through leaf analyses and spectroradiometry, and generate models capable to estimate macro and micronutrients from reflectancy data. Results indicate that the E. grandis population, of 44 months old, shows deficiencies of P, S, B; Cu and Mn showed high contents; N was the only nutrient showing significant differences; there is no significant differences between climatic seasons. For the E. grandis population of 20 months old, variations observed in the nutrients contents were equal to those of the former area; the winter sesason showed a differente behaviour from the other climatic seasons. For the different soil managements, the macro and micronutrients did not vary significantly. Evaluating the reflectancy data for the leaves of E. grandis, of 20 months old, it was concluded that: 1) the summer and spring seasons statistically interfered on the reflectancy; 2) samples of vegetative material may be collected independently of the type of soil management; and, 3) the spectral wavebands that better expresses the vegetation behaviour were the 12, 8, 7 and 3; and, 4) the evaluation of points where the leaves were sampled (East, West, North, South and central) in the no-tillage soil management treatment indicated that: a) sampling of vegetative material should be done separating the central part of the bordering population; and, b) the waveband that better characterized the spectral response of the vegetation was that of number eight. Analysis of the main components indicated the 8, 11 na 12 wavebands as responsible for a total of 98.10% of the reflectancy values under study. The elements P and K showed low adjusted correlation coefficients while generating models considering the elements as dependent variables from reflectancy and climatic seaso;n interacting with wavelengths; the r2aj. values for the remaining elements varied from moderate to high. / Com o intuito de desenvolver estudos relacionando a espectrorradiometria de laboratório com os teores de macro e micronutrientes em materiais vegetativos de povoamentos florestais de Eucalyptus grandis W. Hill ex Maiden, com diferentes idades, uma área experimental foi selecionada para estudo na Fundação Estadual de Pesquisas Agropecuárias FEPAGRO FLORESTAS, Santa Maria, Rio Grande do Sul, Brasil. A partir da proposta de estudar o comportamento espectral, os objetivos específicos foram: 1) avaliar os teores de macro e micronutrientes de folhas de E. grandis nas quatro estações climáticas do ano em diferentes tipos de preparo de solo; 2) avaliar o comportamento espectral de folhas de Eucalyptus grandis abrangendo o intervalo de comprimento de onda de 475 a 980ηm, e abordar as interações: períodos sazonais, preparos de solo e a localização cardeal das árvores amostradas; 3) avaliar o estado nutricional de folhas de plantas jovens de E. grandis por análise foliar e espectrorradiometria e gerar modelos capazes de estimar os teores de macro e micronutrientes a partir de dados de reflectância. Os resultados indicam que o povoamento de E. grandis, com 44 meses de idade, apresenta deficiência de P, S e B; Cu e Mn apresentam teores elevados; N é o único nutriente que apresenta diferença significativa; entre as estações climáticas não existem diferenças significativas. Para o povoamento de E. grandis com 20 meses, as variações obtidas para os teores de nutrientes foram iguais as da área anterior; a estação inverno apresentou comportamento diferenciado das demais estações. Para os diferentes preparos de solo os macro e micronutrientes, não variaram significativamente. Avaliando os dados de reflectância de folhas de E. grandis, com 20 meses de idade, conclui-se que: 1) as estações verão e primavera interferiram estatisticamente na reflectância; 2) as amostras de material vegetativo podem ser coletadas independentemente do tipo de manejo do solo; 3) as bandas espectrais que melhor expressaram o comportamento da vegetação, foram as bandas 12, 8, 7 e 3; e, 4) a avaliação das posições em que as folhas foram coletas (Leste, Oeste, Norte, Sul e central) no tratamento com preparo de solo plantio direto indicaram que: a) as coletas de material vegetativo devem ser realizadas separando a parte central do povoamento da bordadura; e, b) a banda que melhor caracterizou a resposta espectral dessa vegetação foi a de número oito. A análise de componentes principais indicou as bandas 8, 11 e 12, como responsáveis por um total de 98,10% dos valores de reflectância em estudo. Ao gerar modelos considerando os elementos como variáveis dependentes da reflectância e estação do ano interagindo com comprimentos de onda, os elementos P e K apresentaram os valores dos coeficientes de correlação ajustados baixos; os valores de r2aj. dos demais elementos variaram de moderados a altos.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Rare earth elements, or lanthanides, are commonly applied to plants at Chinese agriculture, as fertilizers. Brazil doesn t have any appointment of it utilization in agriculture. Experiments were conduced to evaluate effects of rare earth elements, cerium (Ce) and lanthanum (La), on seeds physiological quality of lettuce, corn, bean and soybean, growth and development of corn and soybean plants then seed treatment with this elements. For this, seeds of different species, on separated experiments, were treated for immersion in watery solutions of Ce or La, in different concentrations, for one or two hours. Were applied, at laboratory, tests of germination, first counting of germination, vigor classification of seedlings, seedlings length, dry mass and thermal stress. The experimental design was completely randomized with treatments composed of Ce or La concentrations and four replications. For corn and soybean were installed experiments at field. Were evaluated: emergency (corn and soybean), leaf number, height, diameter of colm, bloom and yield (in maize). Treatments were composed of different Ce or La concentrations and four replications. Results shows that Ce and La application at seeds influenced, in the majority of the cases, germination and vigor of seedlings. Seedlings length and dry mass were influenced by elements. Ce and La were absorbed by seeds and translocated to seedlings. At field didn t observe effects of Ce and La at corn growth and development, and at soybean emergency, but Ce treatment increased corn yield. / Os elementos terras raras, ou lantanídeos, são comumente fornecidos às plantas na agricultura chinesa, na forma de fertilizantes. No Brasil não há qualquer registro de sua utilização na agricultura. Conduziram-se experimentos com o objetivo de avaliar os efeitos dos elementos terras raras, cério (Ce) e lantânio (La), sobre a qualidade fisiológica de sementes de alface, milho, feijão e soja e; crescimento e desenvolvimento de plantas de milho e soja após tratamento das sementes com os elementos. Para tal, as sementes das diferentes espécies, em experimentos separados, foram tratadas por meio de imersão em soluções aquosas de Ce ou de La, em diferentes concentrações, por uma a duas horas. Em seguida, foram aplicados, em laboratório, os testes de germinação, primeira contagem de germinação, classificação do vigor de plântulas, comprimento, massa seca de plântulas e estresse térmico. Os tratamentos foram compostos por diferentes concentrações de Ce ou La e quatro repetições. Em milho e soja foram instalados experimentos em campo. Após o tratamento das sementes foram avaliados: emergência (em milho e soja), número de folhas, estatura, diâmetro do colmo, florescimento e rendimento (em milho). Os resultados mostraram que a aplicação de Ce e La nas sementes influenciou, na maioria dos casos, a germinação e o vigor. O comprimento e a massa seca das plântulas também responderam a aplicação dos elementos. Para todas as espécies, tanto o Ce quanto o La foram absorvidos pelas sementes em solução aquosa e ocorreu translocação para as plântulas. Em campo não foram observados efeitos do Ce e do La sobre o crescimento e desenvolvimento de plantas de milho e sobre a emergência da soja, mas, o tratamento com Ce foi capaz de aumentar o rendimento final da cultura do milho.

Orientador: Salatiér Buzetti / Banca: Marlene Cristina Alves / Banca: Francisco Maximino Fernandes / Banca: Edson Cabral da Silva / Banca: William Natale / Resumo: Apesar de o milho apresentar um elevado potencial produtivo, vários fatores influenciam sua produtividade. Assim, objetivou-se avaliar alguns dos componentes de produção e a produtividade da cultura em função da adubação nitrogenada via solo e da aplicação de fungicida, cobre e manganês via foliar na cultura do milho. Os experimentos, com quatro repetições, em blocos casualizados e arranjo fatorial 2x2x2x2 (dois níveis de N, fungicida, cobre e manganês), foi conduzido em Chapadão do Sul - MS, em solo de textura argilosa, nos anos 2007 e 2008. A altura de plantas no florescimento e o número de fileiras de grãos por espiga não foram influenciados pelos tratamentos em ambos os anos de estudo. Para a adubação nitrogenada, houve efeito significativo para os componentes de produção avaliados, sendo o diâmetro de colmo aumentado em 2008 e o diâmetro de espiga e a massa de 100 grãos aumentados em ambos os anos. As doses de nitrogênio aumentaram os teores foliares deste elemento em 2007 e não influenciaram a severidade de doenças em ambos os anos. O uso de fungicida aumentou os teores foliares de nitrogênio, diminuiu a severidade de doenças e aumentou a produtividade em 2007 e 2008, apesar da inexistência de correlação significativa entre severidade e produtividade. A pulverização com sulfato de cobre e sulfato de manganês não influenciou os teores foliares destes elementos, os componentes de produção, exceto para a aplicação de cobre associado ao manganês na ausência de fungicida e na dose de 40 kg ha-1 de N em 2008. Houve efeito depressivo no comprimento de espiga, sem, contudo afetar a produtividade da cultura do milho safrinha e, a aplicação de manganês que aumentou o diâmetro de espiga em 2008. A produtividade de grãos de milho foi incrementada pelo uso de fungicida em ambos os anos e pela adubação nitrogenada no ano de 2008 / Abstract: Although corn has a high productive potential, several factors influence its productivity. Therefore, the aim was to evaluate some of the components of production and crop yield as a function of nitrogen in the soil and the fungicide, copper and manganese foliar application on corn. The experiment with four replications in randomized blocks and factorial 2x2x2x2 (two levels of N, fungicide, copper and manganese), was conducted in Chapadão do Sul - MS in clayey soil in the years 2007 and 2008. Plant height at flowering and the lines number per ear were not affected by treatments in both years of study. For nitrogen, there was a significant effect on yield components evaluated, and the stem diameter increased in 2008, ear diameter and the mass of one hundred grains increased in both years. The doses of nitrogen increased the leaf contents of this element in 2007 and did not influence disease severity in both years. The use of fungicide increased the concentration of leaf nitrogen, decreased the severity of disease and increased productivity in 2007 and 2008, despite the lack of significant correlation between severity and yield. Spraying with copper sulphate and manganese chelate did not influence the leaf content of these elements, as well a yield components, except for the application of copper associated with manganese in the absence of fungicide at 40 kg ha-1 N in 2008. There was a restrictive effect on ear length, but without affecting the yield of corn grown in no season, and the application of manganese increased the diameter of the ear in 2008. The grain yield of corn was increased by the use of fungicide in both years and fertilization in the year 2008 / Doutor

Made available in DSpace on 2016-08-31T13:15:06Z (GMT). No. of bitstreams: 1 TalitaBAD_DISSERT.pdf: 1199750 bytes, checksum: 6beacf2ab995069e2c168a6be1d1f249 (MD5) Previous issue date: 2012-03-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The production of castor bean in the Apodi Plateau can be used as an alternative to crop rotation schemes aimed at economic and environmental sustainability of areas traditionally cultivated cucurbits. For the castor produce satisfactorily, the adaptation to climate conditions and the use of appropriate farming is essential to have supplies of water and nutrients. In alkaline soils, the availability of some nutrients become limited, especially micronutrients; nitrogen, when applied in this type of soil can be quickly lost to the atmosphere by volatilization of ammonia, and the main occurrence of this loss occurs with the use of urea. This work aimed to evaluate the response of castor bean doses of potassium, boron, zinc, copper, magnesium and nitrogen sources applied at planting and coverage in order to contribute to the improvement of its productive system in the Apodi Plateau . In experiment 01, 10 treatments were compared regarding the soil application of five doses of potassium (0, 25, 50, 75 and 100 kg ha-1) and five doses of boron (0.0, 0.5, 1.0, 2.0 and 3.0 kg ha-1). In experiment 02, compared to seven treatments with the aim of evaluating the effects of the presence and absence of fertilization with Zn, Cu and Mg and the effects of forms of use (cultivation and or coverage) of N sources (urea and , or, ammonium sulfate). At 47 days after emergence composite samples were collected at depth 0-20 cm from the floor area of each plot, to determine the levels of K, Zn, Cu and Mg available. At the beginning of flowering of castor beans was assessed the nutritional status of plants, determining the K, B, Zn, Cu, Mg, S and N in the leaves. At the end of the experiment were evaluated: plant height, height of insertion of the primary raceme, stem diameter, number of racemes per plant, thousand grain weight of the raceme and primary and subsequent productivity. Under the experimental conditions, the average productivity of castor beans was 2.019 kg ha-1 grain, without requiring fertilization with potassium, boron, copper, zinc and magnesium, and indiscriminately using urea or ammonium sulfate as nitrogen source for crop fertilization and or cover, incorporated into the soil 5 cm in depth / A produção da mamona na Chapada do Apodi pode ser utilizada como alternativa para os sistemas de rotação de culturas que visem à sustentabilidade econômica e ambiental de áreas tradicionalmente cultivadas com cucurbitáceas. Para que a mamona produza satisfatoriamente, além de adaptação às condições edafoclimáticas e da utilização da cultivar adequada, é imprescindível que haja suprimentos de água e de nutrientes. Em solos alcalinos, a disponibilidade de alguns nutrientes torna-se restrita, principalmenteos micronutrientes; o nitrogênio, quando aplicado neste tipo de solo pode ser rapidamente perdido para atmosfera por volatilização da amônia, e a principal ocorrência dessa perda acontece com a utilização de uréia. Neste trabalho objetivou-se avaliar a resposta da cultura da mamona a doses de potássio, boro, zinco, cobre, magnésio e a fontes de nitrogênio aplicadas no plantio e em cobertura, de forma a contribuir para a melhoria do seu sistema produtivo na Chapada do Apodi. No experimento 01, foram comparados 10 tratamentos referentes à aplicação, no solo, de cinco doses de potássio (0, 25, 50, 75 e 100 kg ha -1) e cinco doses de boro (0,0, 0,5, 1,0, 2,0 e 3,0 kg ha -1). No experimento 02, compararam-se sete tratamentos, com o objetivo de avaliar os efeitos da presença e ausência de adubação com Zn, Cu e Mg e os efeitos de formas de utilização (plantio e, ou, cobertura) de fontes de N (uréia e, ou, sulfato de amônio). Aos 47 dias após a emergência foram coletadas amostras compostas de solo na profundidade de 0 a 20 cm da área útil de cada parcela, para determinação dos teores de K, Zn, Cu e Mg disponíveis. No início do florescimento da mamoneira foi avaliado o estado nutricional das plantas, determinando-se os teores de K, B, Zn, Cu, Mg, S e N nas folhas. Ao final do experimento, foram avaliadas a altura da planta, altura de inserção do racemo primário, o diâmetro do caule, número de racemos por planta, massa de mil grãos do racemo primário e subsequentes e produtividade. Nas condições experimentais, a produtividade média da mamoneira foi 2.019 kg ha-1 de grãos, sem necessitar de adubação com potássio, boro, cobre, zinco e magnésio, e utilizando indistintamente a uréia ou sulfato de amônio como fonte de nitrogênio para adubação de plantio e, ou, de cobertura, incorporada no solo a 5 cm de profundidade

Submitted by DIÊGO VICTOR DE BABOS null (diegobabos@hotmail.com) on 2016-08-08T23:38:08Z No. of bitstreams: 1 Dissertação Diêgo Babos.pdf: 1989792 bytes, checksum: 30376a94b5f5cac12b35744978cd6cc7 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-11T14:14:27Z (GMT) No. of bitstreams: 1 babos_dv_me_araiq_par.pdf: 1035449 bytes, checksum: 4a4c8a9a99f92024681ea27985b94b19 (MD5) / Made available in DSpace on 2016-08-11T14:14:27Z (GMT). No. of bitstreams: 1 babos_dv_me_araiq_par.pdf: 1035449 bytes, checksum: 4a4c8a9a99f92024681ea27985b94b19 (MD5) Previous issue date: 2016-07-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Avaliou-se a amostragem direta de sólidos como base de métodos analíticos simples, rápidos e mais limpos para determinar Co, Mo, Ni e V em tecido vegetal e solo empregando a espectrometria de absorção atômica de alta resolução com fonte contínua. Esta técnica foi escolhida devido as suas características peculiares, especialmente a elevada capacidade de correção de fundo. Na determinação de cobalto em material vegetal, a sobreposição espectral de SiO(g) na linha 240,725 nm do Co foi corrigida pelo método dos mínimos quadrados. Curvas de calibração (0–540 pg) com bons coeficientes de correlação lineares (R 0,9993) foram obtidas com padrões sólidos. O limite de detecção (LOD) foi 3 pg Co. Na determinação simultânea de Mo e Ni em material vegetal, empregou-se Co como padrão interno para Ni. Curvas de calibração (0,8-50 ng Ni; 0-0,33 ng Mo) lineares (R 0,9937) foram obtidas com padrões aquosos sem modificador químico. Os LODs foram 0,018 ng Mo e 0,025 ng Ni. A padronização interna aumentou a precisão das medidas para Ni de 62-135% para 94-105%. Vanádio e Co foram determinados em solos empregando NH4F como modificador. As calibrações, com padrões aquosos para V (0-40 ng), e por compatibilização de matriz para Co (0-5,0 ng), forneceram R 0,9979. Os LODs foram 0,044 ng Co e 0,43 ng V. Na determinação de Mo e Ni em solo, o modificador Mg(NO3)2 foi utilizado apenas para Ni. As curvas de calibração aquosas (0-500 ng Ni; 0-0,54 ng Mo) forneceram R 0,9953. Na determinação do Ni foi monitorado o tripleto em 341,377 nm, 341,347 nm e 341,394 nm, permitindo determinar Ni em ampla faixa de concentração. Os LODs foram 0,0082 ng Mo (313,259 nm), 0,021 ng Ni (341,477 nm),1,8 ng Ni (341,347 nm). A exatidão dos métodos foi avaliada via análise de materiais de referência certificados de solos e plantas. De uma forma geral, os resultados obtidos foram concordantes com os valores certificados ao nível de confiança de 95%. / High-resolution continuum source atomic absorption spectrometry with direct solid sampling was employed for the development of simple, fast and clean analytical methods for Co, Mo, Ni and V determination in soil and plant materials. The technique has as main advantages the efficiency to correct background absorption. For cobalt determination in plant material, a spectral overlap of SiO molecular absorption in Co line was corrected by using least squares background correction method. Calibration curves (0-540 pg) with correlation coefficients higher of 0.9993 were obtained with solid standards. The limit of detection was of 3 pg Co. For simultaneous determination of Mo and Ni in plant material Co was employed as internal standard for Ni. Calibration curves (0.8-50 ng Ni; 0-0.33 ng Mo) with correlation coefficients higher of 0.9937 were obtained with aqueous standards without chemical modifier. The LODs were 0.025 and 0.018 ng for Mo and Ni, respectively. The internal standardization increased the accuracy of Ni determinations from 62-135% to 94-105%. For V and Co determinations in soils the NH4F was used as chemical modifier. The calibration with aqueous standards for V (0-40 ng), and compatibility matrix for Co (0-5.0 ng), provided linear correlation coefficients better of 0.9979. The LODs were 0.044 and 0.43 ng for Co and V, respectively. For Mo and Ni determination in soil the Mg(NO3)2 was used as chemical modifier for Ni. The aqueous calibration curves (0-500 ng Ni; 0-0.54 ng Mo) provided linear correlation coefficients higher of 0.9953. For Ni determination were used the triplet lines at 341.377 nm, 341.347 nm and 341.394 nm, allowing the determination of Ni in wide concentration range. The calculated LODs were 0.0082 ng Mo (313.259 nm), 0.021 ng Ni (341.477 nm), 1.8 ng Ni (341.347 nm). The accuracy of the proposed methods was assessed by analysis of certified reference materials of soils and plants. In general, the results were in agreement with the certified values at 95% confidence level (t-test).

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aimed to evaluate the effect of silicon and copper concentrations in the nutrient solution for lettuce soilless production. Four experiments were conducted at Plant Science Department of the Federal University of Santa Maria in a closed soilless system using 3 dm3 pots with sand. Two experiments were with silicon, from June 17 to August 11 in winter and from 26 September to 24 October, 2014, in spring. Treatments were five silicon concentrations in the nutrient solution, two lettuce cultivars, Veneranda (crisphead) and Stella (butterhead), and foliar spaying of silicon seven days before harvest. Silicon concentrations in the nutrient solution were 0.0; 0.7; 1.4; 2.1 and 2.8 mmol L-1 and 0.0; 1.4; 2.8; 4.2 and 5.6 mmol L-1, respectively, and 9 mg L-1 in foliar spaying. The experimental design was a randomized factorial 5x2x2 split plot with 11 replications. Other two experiments were conducted with copper, from 27 October to 26 November, 2014, in spring and from May 8 to June 22, 2015, in fall, using the same cultivars. Copper concentrations in the nutrient solution were 0.06; 0.18; 0.3; 0.42 and 0.54 mg L-1 and 0.05; 0.75; 1.25; 1.75 and 2.25 U mg L-1, respectively. The experimental design was a randomized factorial 5x2 split plot with 11 replications. Increasing the silicon concentration reduced growth and development of plants of both cultivars and reduced also the post-harvest fresh weight loss on Stella plants. It was concluded that in the range of concentrations used in present experiments any beneficial effect of silicon on lettuce production can be expected, but it may reduce post-harvest fresh weight loss. Growth and production were reduced by copper concentrations on both cultivars and seasons and it was concluded that concentrations higher than 0.06 mg L-1 in the root medium have to be avoided. / O trabalho teve como objetivo avaliar o efeito da concentração de silício e cobre na produção de alface em cultivo sem solo. Quatro experimentos foram realizados no Departamento de Fitotecnia da Universidade Federal de Santa Maria em sistema fechado de cultivo sem solo empregando vasos de 3 dm3 com areia. Dois experimentos foram realizados com silício no inverno, entre 17 de junho e 11 de agosto e entre 26 de setembro e 24 de outubro de 2014, na primavera. Os tratamentos foram constituídos de cinco concentrações de silício na solução nutritiva, duas cultivares de alface, Veneranda (crespa) e Stella (lisa) e pulverização foliar de silício aos sete dias antes da colheita. As concentrações de silício na solução nutritiva foram 0,0; 0,7; 1,4; 2,1 e 2,8 mmol L-1 e 0,0; 1,4; 2,8; 4,2 e 5,6 mmol L-1, respectivamente, e de 9 mg L-1 na pulverização foliar. O delineamento experimental foi casualizado, com parcelas subdivididas, em esquema fatorial 5x2x2, com 11 repetições. Outros dois experimentos foram realizados com cobre, entre 27 de outubro e 26 de novembro de 2014 na primavera e entre 8 de maio e 22 de junho de 2015 no outono, com as mesmas cultivares. As concentrações de cobre na solução nutritiva foram de 0,06; 0,18; 0,3; 0,42 e 0,54 mg L-1 e 0,05; 0,75; 1,25; 1,75; 2,25 mg L-1, respectivamente. O delineamento experimental foi casualizado em parcelas subdivididas e esquema fatorial 5x2, com 11 repetições. O aumento da concentração de silício reduziu o crescimento e desenvolvimento das plantas de ambas as cultivares e reduziu também a perda de massa fresca pós-colheita da cultivar Stella. Concluiu-se que nas concentrações testadas não há efeito benéfico do silício na produção da alface em cultivo sem solo, apenas na redução da massa fresca pós-colheita. As concentrações de Cu reduziram a produção em ambas as cultivares e épocas, concluindo-se que concentrações em torno das raízes superiores a 0,05 mg L-1 devem ser evitadas.

Orientador: Salatiér Buzetti / Banca: Francisco Maximino Fernandes / Banca: Marcelo Andreotti / Banca: Edson Luiz Mendes Coutinho / Banca: Renato de Mello Prado / Resumo: São utilizadas várias fontes de B e Zn nas adubações foliares como ácidos, sulfatos, óxidos inorgânicos e quelatos. Assim, a aplicação de fertilizantes via foliar vem sendo realizada com relativa freqüência, sendo que os resultados dessas aplicações são ainda controvertidos. Neste contexto, o objetivo deste trabalho foi verificar o efeito da aplicação de fertilizantes foliares com B e Zn sobre a nutrição, produção e qualidade dos frutos de pereira japonesa. O experimento foi conduzido no período de 2004 a 2007, no município de Ilha Solteira, localizado na região noroeste do Estado de São Paulo-Brasil. Foram utilizadas plantas de pereira japonesa, cv. Okusankichi, enxertada em pyrus communis L., com três anos de idade, irrigadas por microaspersão e fontes nas doses de 110 g ha-1 de B e 250 g ha-1 de Zn em cada tratamento, sendo os tratamentos: T1. Apenas água; T2. Ácido bórico; T3. Sulfato de zinco; T4. T2 + T3; T5. Ácido bórico + uréia + ácido cítrico + EDTA; T6. Sulfato de zinco + uréia + ácido cítrico + EDTA; T7. T5 + T6; T8. Ácido bórico + uréia + ácido cítrico + EDTA + molibdato de sódio + enxofre + cloreto de cálcio; T9. Sulfato de zinco + uréia + ácido cítrico + EDTA + sulfato ferroso + sulfato de Mn + sulfato de Mg e T10. T8+T9. Adotou-se o delineamento experimental em blocos ao acaso com quatro repetições e compararam-se as médias utilizando-se o teste de Tukey a 5%. Com base nos resultados obtidos pode-se concluir que: 1. O produto comercial 8 (Ácido bórico + uréia + ácido cítrico + EDTA + molibdato de sódio + enxofre + cloreto de cálcio) foi mais eficiente no fornecimento de B às plantas; bem como, o produto comercial 6 (Sulfato de zinco + uréia + ácido cítrico + EDTA) foi mais eficiente no fornecimento de Zn à pereira japonesa; 2. Os aumentos...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The application leaf spray fertilization of boron and zinc has been often used; the results of these applications are misinterpreted yet. In this context, the objective of this research was to verify the effect of leaf spray fertilization of B and Zn on the nutrition, production and quality of fruits of Japanese pear tree. The experiment was conducted in the period from 2004 to 2007, in Ilha Solteira, northwestern Sao Paulo State - Brazil. It was used plants of Japanese pear tree, Okusankichi cultivar, grafted on pyrus communis L. rootstock as well as doses of 110 g ha-1 of B e 250 g ha-1 of Zn in each application according each treatment, which were: T1. Water; T2. Boric acid; T3. Zinc sulfate; T4. T2 + T3; T5. Boric acid + urea + citric acid + EDTA, T6. Zzinc sulfate + urea + citric acid + EDTA, T7. T5 + T6, T8. Bric acid + urea + citric acid + EDTA + sodium molibdate + sulfur + calcium chloride, T9. Zinc sulfate + urea + citric acid + EDTA + Fe sulfate + Mn sulfate + Mg sulfate and, T10. T8+T9. A randomized blocks design was used and the averages were compared by Tukey test at 5%. Based on the results we may conclude that: 1. The commercial product to treatment n.8 (boric acid + urea + citric acid + EDTA + sodium molibdate + sulfur + calcium chloride) was efficient to provide B to Japanese pear tree, as well as, that to treatment n. 6 (zinc sulfate + urea + citric acid + EDTA) was efficient to provide Zn to Japanese pear tree, 2. The increasing of the leaf contents of B and Zn were not sufficient to modify the components of production, 3. The commercial product to treatment n. 5 (boric acid + urea + citric acid + EDTA) promoted an elevation of total titratable acidity. / Doutor