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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.
181

Suprimento de enxofre e a toxidez por cromo no capim tanzânia / Sulphur supply and chromium toxicity in tanzania guinea grass

Gonçalves, Janine Mesquita 11 January 2018 (has links)
Espécies vegetais cultivadas em ambientes com altas concentrações de cromo (Cr) apresentam danos estruturais e baixa produção de massa seca da parte aérea e das raízes. O enxofre (S) é capaz de aliviar a toxidez provocada por metais pesados por ativar enzimas antioxidantes e produzir compostos capazes de imobilizar os metais. Objetivou-se avaliar as modificações estruturais, nutricionais e bioquímicas ocorridas no capim tanzânia crescendo com três doses de S (0,1; 1,9 e 3,7 mmol L-1) combinadas com quatro doses de Cr (0,0; 0,5; 1,0 e 2,0 mmol L-1), em solução nutritiva. O experimento foi conduzido em casa de vegetação em período de verão, utilizando um fatorial no delineamento de blocos completos casualizados, com seis repetições. O primeiro corte do capim foi realizado 33 dias após o transplantio das mudas para os vasos e o segundo corte 25 dias após o primeiro. O S amenizou o efeito tóxico do Cr aumentando a emissão de folhas e perfilhos e promovendo maior produção de massa seca de parte aérea. O índice relativo de clorofila (valor SPAD) nas lâminas recém-expandidas relacionou-se com os sintomas de clorose e necrose observados no primeiro crescimento. A dose residual de Cr estimulou a atividade fotossintética das folhas que apresentaram tonalidade verde escuro. Houve aumento na concentração e no acúmulo de S e de Cr na parte aérea do capim tanzânia com o fornecimento das doses combinadas do nutriente com o metal. A deficiência de S fez aumentar as concentrações de fósforo e de cobre na parte aérea. O capim absorveu maiores quantidades de micronutrientes para controlar o estresse provocado pela toxidez do Cr. A taxa fotossintética do capim tanzânia foi menor nas plantas contaminadas com Cr o que causou maior atividade das enzimas catalase, ascorbato peroxidase, guaiacol peroxidase e glutationa redutase na parte aérea. Aumento na concentração do peróxido de hidrogênio foi observado pela maior atividade da enzima superóxido dismutase quando foi utilizada dose de S de 0,1 mmol L-1 combinada com as doses de Cr, principalmente nas demais partes - folhas mais maduras, colmos e bainhas. O S amenizou o efeito tóxico do Cr no capim tanzânia aumentando as emissões de folhas e de perfilhos, a produção de biomassa, a absorção de micronutrientes e a atividade da enzima guaiacol peroxidase. O estresse por deficiência de S ou excesso de Cr resultou em aumento na síntese de prolina. O capim tanzânia possui habilidade em sobreviver sob contaminação com Cr quando adequadamente nutrido com S. / Plant species grown in environments with high concentrations of chromium (Cr) exhibit structural damage and lower dry mass production of shoot and root. Sulfur (S) is able to aleviatte the toxicity caused by heavy metals by activating antioxidant enzymes and producing compounds capable of immobilizing heavy metals. The aim was to evaluate structural, nutritional and biochemical changes occurring in tanzania guinea grass growing with three doses of S (0.1, 1.9 and 3.7 mmol L-1) combined with four doses of Cr (0.0, 0.5, 1.0 and 2.0 mmol L-1) in nutrient solution. The experiment was conducted in a greenhouse during the Summer season, by using a factorial in a randomized complete block design with six replications. The first harvest of the grass was done at 33 days after the transplanting of seedlings to the pots and second harvest at 25 days after the first one. S decreased the toxic effect of Cr increasing the emission of leaves and tillers and promoting higher production of shoots dry mass. Relative chlorophyll index (SPAD value) in newly expanded lamina leaves was associated to symptoms of chlorosis and necrosis observed in the plants during the first growth. Residual Cr stimulated photosynthetic activity of leaves, which presented dark green color. There was an increase in the concentrations and accumulations of S and Cr in shoots of tanzania guinea grass with the supply of combined rates of nutrient and metal. S deficiency increased the concentrations of phosphorus and copper in shoots. The grass uptook larger amounts of micronutrients to control stress caused by toxicity of Cr. The photosynthetic rate in tanzania guinea grass was low in contaminated plants, which resulted in high activity of the enzymes catalase, ascorbate peroxidase, guaiacol peroxidase and glutathione reductase in the shoots. The increase in hydrogen peroxide concentration was observed due to the high activity of the superoxide dismutase enzyme when the S rate was 0.1 mmol L-1 in combination with Cr rates, mainly in the more mature leaves, culms and sheaths. S alleviated the toxic effect of Cr in tanzania guinea grass by increasing leaf emission, tillering, biomass production, micronutrient uptake and guaiacol peroxidase enzyme activity. Stress caused for sulfur deficiency or Cr excess result in high synthesis of proline. Tanzania guinea grass has ability to survive under Cr contamination when adequately supplied with S.
182

EFEITO DE PRODUTOS ALTERNATIVOS PARA O CONTROLE DA ANTRACNOSE EM FEIJÃO

Truylio, Carlos Eduardo Carbonar 18 August 2015 (has links)
Made available in DSpace on 2017-07-25T19:30:51Z (GMT). No. of bitstreams: 1 Carlos E C Truylio.pdf: 2023652 bytes, checksum: f7445141bbdc3047ed1e8401c8bc1697 (MD5) Previous issue date: 2015-08-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / management of crop diseases. The objective of this study was to evaluate different alternative products against anthracnose, with the detached leaf assay method, and in field conditions in common beans. The experiment with detached leaf assay method was conducted in laboratory. The experimental design was completely factorial randomized in a factorial arrangement 10 (treatment) x 2 (application or not in half the leaf) with 5 repetitions. The evaluation of severity and area under the anthracnose progress curve was performed. The experiments under field conditions were conducted in 2013/2014 and 2014/2015 harvest, at Fazenda Escola Capão da Onça. The experimental had a randomized blocks design, with four repetitions. The evaluation of severity, area under the disease progress curve and anthracnose index in the pods, in addition to crop production components were performed. The treatments for the experiments were: 1- V- 6 (Meristem enzymes, 5,4%; Mn, 2,5%; Zn, 1,9%; Mo, 0,16%), 2- Wert plus (toxins produced by cultivating from different microorganisms, such as Bacillus subtilis, Gliocladium catenulatum, Trichoderma sp, Trichoderma harzianum, Azotobacter chroococcum, e micronutrients Cu, Zn e Mg), 3- High Roots (12% of seaweed; 4,8% of K2O; 0,2% of CaO), 4- Max Fruit (4,61% of calcium), 5- Rocksil (20,56% of Al2O3, 17,43% of SiO2; 9,82% of S; 1,31 of CaO; 0,34% of TiO2; 0,18 of MgO; 0,16% of Fe2O3; 0,1% of P2O5), 6- Herbagreem (36,7% of CaO; 17 to 20% of SiO2; 2,4% of MgO; 3,4% of Fe2O3; 0,7% of K2O; 0,5% of Na2O; 0,4% of SO3; 0,2% of P2O5; 0,1% of MnO; 1 mg kg-1 of B; 13 mg kg-1 of Co; 26 mg kg-1 of Cu; 34 mg kg-1 of Zn), 7-Fluisan (hop extract: 80,7 %), 8- Herbagreen + Fluisan, 9- trifloxystrobin + tebuconazol and 10- control. In the detached leaf assay, Wert Plus had a negatively influence, increasing the severity of the disease. At field conditions, there was no statistical difference in severity between treatments in both harvests. The Wert Plus treatment had a higher rate of anthracnose on pods in 2013/2014 harvest. The yield components of culture, number of plants per meter, number of pods per plant, number of seeds per pod, weight of 100 grains and productivity were not affected by treatments. / manejo das doenças de plantas cultivadas. O objetivo deste trabalho foi avaliar o efeito de diferentes produtos alternativos, contra a antracnose na cultura do feijão, em experimento em folha destacada e em condições de campo. O experimento em folha destacada foi conduzido em laboratório. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 10 (produtos) x 2 (aplicação ou não em metade da folha) com 5 repetições. Foi realizada a avaliação de severidade e calculada a área abaixo da curva de progresso da antracnose. Os experimentos em condições de campo foram realizados nas safras 2013/2014 e 2014/2015, na Fazenda Escola Capão da Onça. O delineamento experimental foi de blocos ao acaso com 4 repetições. Foi realizada a avaliação da severidade, calculada a área abaixo da curva de progresso da doença e o índice de antracnose nas vagens, além dos componentes de rendimento da cultura. Os tratamentos realizados foram: 1 - V-6 (5,4% de enzimas de meristema;2,5% de Mn; 1,9% de Zn; 0,16% de Mo,), 2 - Wert plus (toxinas produzidas pelo cultivo de diferentes microrganismos: Bacillus subtilis, Gliocladium catenulatum, Trichoderma sp, Trichoderma harzianum, Azotobacter chroococcum, e micronutrientes (Cu, Zn e Mg), 3 - High Roots (algas marinhas a 12%; K2O a 4,8%; CaO a 0,2%), 4 - Max Fruit (4,61% de cálcio), 5 - Rocksil (20,56% de Al2O3, 17,43% de SiO2; 9,82% de S; 1,31 de CaO; 0,34% de TiO2; 0,18 de MgO; 0,16% de Fe2O3; 0,1% de P2O5), 6 - Herbagreem (36,7% de CaO; 17 a 20% de SiO2; 2,4% de MgO; 3,4% de Fe2O3; 0,7% de K2O; 0,5% de Na2O; 0,4% de SO3; 0,2% de P2O5; 0,1% de MnO; 1 mg kg-1 de B; 13 mg kg-1de Co; 26 mg kg-1 de Cu; 34 mg kg-1 de Zn), 7 - Fluisan (extrato de lúpulo: 80,7 % de planta e 19,3% de água), 8 - Herbagreen + Fluisan, 9 - trifloxistrobina + tebuconazole e 10 - testemunha. No teste da folha destacada, os tratamentos V-6, Wert Plus, High Roots, Max Fruit, Rocksil, Herbagreem, Fluisan, Herbagreen +Fluisan e trifloxistrobina + tebuconazole, não apresentaram potencial de induzir resistência contra C. lindemuthianum. O tratamento Wert Plus aumentou a severidade da doença. No experimento a campo, não se observou diferença estatística na severidade entre os tratamentos nas duas safras. O tratamento Wert Plus apresentou um maior índice de antracnose nas vagens na safra 2013/2014. Os componentes de rendimento da cultura, número de plantas por metro, número de vagens por planta, número de grãos por vagem, massa de 100 grãos e produtividade não foram afetados pelos tratamentos.
183

Aplicação foliar de molibdênio e cobalto na cultura da soja : rendimento e qualidade de sementes / Foliar Application of Molybdenum and Cobalt in Soybean: Yield and Seed Quality

Dalmolin, Adhyvan Karmo 18 August 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-04-03T12:43:52Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_adhyvan_karmo_dalmolin.pdf: 1510521 bytes, checksum: 38b309e7f6b36a685bcf42f2e4c0bfea (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:49:11Z (GMT) No. of bitstreams: 2 dissertacao_adhyvan_karmo_dalmolin.pdf: 1510521 bytes, checksum: 38b309e7f6b36a685bcf42f2e4c0bfea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:50:28Z (GMT) No. of bitstreams: 2 dissertacao_adhyvan_karmo_dalmolin.pdf: 1510521 bytes, checksum: 38b309e7f6b36a685bcf42f2e4c0bfea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-07T18:50:50Z (GMT). No. of bitstreams: 2 dissertacao_adhyvan_karmo_dalmolin.pdf: 1510521 bytes, checksum: 38b309e7f6b36a685bcf42f2e4c0bfea (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-08-18 / Sem bolsa / O presente trabalho teve como objetivo avaliar a aplicação foliar de produto comercial contendo molibdênio e cobalto na cultura da soja, visando aumento nos componentes de rendimento e qualidade fisiológica das sementes produzidas. O experimento foi realizado na fazenda Sucupira, município de Sorriso, Estado do Mato Grosso. O delineamento experimental adotado foi de blocos casualizados com quatro repetições e seis tratamentos com diferentes doses. O produto usado na aplicação foi o Néctar (cobalto e molibdênio) da empresa Microquímica, aplicado com um pulverizador costal na vazão de 160 L.ha-1. A pulverização ocorreu quando a soja estava no estádio de desenvolvimento V5. Foram conduzidos seis tratamentos (0; 100; 200; 300; 400 e 500 mL.ha-1 do produto comercial). Foi analisado os componentes de rendimento (peso de mil sementes; rendimento de grãos, número de vagens por planta e número de sementes por vagem) a qualidade fisiológica das sementes (primeira contagem da germinação, germinação, envelhecimento acelerado, emergência em campo e tetrazólio) e análise de sanidade (fungos e bactéria). A aplicação foliar de produto comercial contendo cobalto e molibdênio na dose de até 240 mL.ha-1 afeta de forma positiva o número de sementes por vagem da cultura, não houve incrementos significativos na produtividade da soja. As doses de molibdênio e cobalto tem efeito positivo na qualidade fisiológica. / This study aimed to evaluate the effect of molybdenum and cobalt different doses applied by foliar fertilization in the soybean crop, aiming at increasing the yield components and physiological seed quality. The essay was carried out at Sucupira farm, city of Sorriso, in Mato Grosso State. The experimental design was a randomized block with four replications and six treatments with different doses. Product used in the application was the Nectar (cobalt and molybdenum) of Microquímica Company, applied with a backpack sprayer at a flow rate of 160 L.ha-1. Spraying occurred in the V5 growth soybean stage. Six treatments were conducted (0, 100, 200, 300, 400 and 500 commercial product mL.ha-1). It was analyzed the yield components (thousand seed weight, grain yield, number of pods per plant and number of seeds per pod) Physiologic seed quality (first count of germination, standard germination test, accelerated aging, field seedlings emergence and tetrazolium test) and health test (fungi and bacteria). Foliar spraying of cobalt and molybdenum up to 240 mL.ha-1 influences positively the number of seeds per pod culture, there was no significant increase in soybean yield. The doses of molybdenum and cobalt has a positive effect on physiological quality.
184

Ingestão de nutrientes segundo variáveis demográficas e socioeconômicas em adultos brasileiros: Inquérito Nacional de Alimentação - Brasil, 2008-2009 / Nutrient intake according to demographic and socioeconomic variables in Brazilian adults: National Dietary Survey - Brazil, 2008-2009

Marina Campos Araujo 07 October 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A tese descreve a ingestão de nutrientes segundo variáveis demográficas e socioeconômicas em adultos brasileiros, com base nos dados da primeira avaliação nacional do consumo alimentar individual, o Inquérito Nacional de Alimentação (INA), realizado entre 2008 e 2009. Um total de 34.003 indivíduos com pelo menos 10 anos de idade participaram do estudo. O presente estudo incluiu 21.003 indivíduos adultos, de 20 a 59 anos de idade, com exceção das mulheres gestantes e lactantes (n=1.065). O consumo alimentar individual foi estimado utilizando dois dias de registros alimentares não consecutivos. O consumo usual de nutrientes foi estimado pelo método do National Cancer Institute que permitiu a correção da variabilidade intraindividual. As prevalências de ingestão inadequada de nutrientes foram estimadas segundo o sexo e faixas etárias utilizando o método da necessidade média estimada como ponte de corte. A inadequação de sódio foi avaliada pelo consumo acima do nível de ingestão máximo tolerável. Os resultados são apresentados na forma de dois artigos. No primeiro artigo, estimaram-se as prevalências de inadequação segundo as cinco grandes regiões (Norte, Nordeste, Sudeste, Sul e Centro-Oeste) e a situação do domicílio (urbano e rural). Observaram-se prevalências de inadequação maiores ou iguais a 70% para cálcio entre os homens e magnésio, vitamina A, sódio em ambos os sexos. Prevalências maiores ou iguais a 90% foram encontradas para cálcio entre as mulheres e vitaminas D e E em ambos os sexos. No geral, os grupos com maior risco de inadequação de micronutrientes foram as mulheres e os que residem na área rural e na região Nordeste. No segundo artigo, estimaram-se as prevalências de inadequação do consumo segundo renda e escolaridade. A renda foi caracterizada pela renda mensal familiar per capita e a escolaridade definida pelo número de anos completos de estudo. Ambas variáveis foram categorizadas em quartis. Modelos de regressão linear simples e mutuamente ajustados foram estimados para verificar a associação independente entre o consumo de nutrientes e as variáveis socioeconômicas. Foram testadas as interações entre renda e escolaridade. Verificou-se que a inadequação da maioria dos nutrientes diminuiu com o aumento da renda e escolaridade; porém, o consumo excessivo de gordura saturada e o baixo consumo de fibra aumentaram com ambas variáveis. Grande parte dos nutrientes foi independentemente associada à renda e escolaridade, contudo, o consumo de ferro, vitamina B12 e sódio entre mulheres foi associado somente com a educação. Observou-se interação entre renda e escolaridade na associação com o consumo de sódio em homens, fósforo em mulheres e cálcio em ambos os sexos. Os achados indicam que melhorar a educação é um passo importante na melhoria do consumo de nutrientes no Brasil, além da necessidade de formulação de estratégias econômicas que permitam que indivíduos de baixa renda adotem uma dieta saudável. Nossos resultados mostram também um grande desafio das ações de saúde pública na área de nutrição, com importantes inadequações de consumo em toda população adulta brasileira e particularmente em grupos populacionais e regiões mais vulneráveis do país. / The thesis describes the nutrient intake according to demographic and socioeconomic variables in Brazilian adults, based on data from the first national survey of individual food intake. The National Dietary Survey (NDS) was conducted between 2008 and 2009. Total of 34,003 subjects aged 10 years or older participated in the study. The present study included 21,003 Brazilian adults, aged 2059 years, after exclusion of pregnant and lactating women (n= 1,065). Two non-consecutive days of food records were used to estimate individual food intake. National Cancer Institute method allows correcting the within-person variance to estimate the usual nutrient intake. The Estimated Average Requirement (EAR) cut-off point method was used to estimate the prevalence of inadequate nutrient intake according to sex and age group. The sodium inadequacy was estimated by intake above the tolerable upper intake level. The results are presented in two papers. In the first paper, prevalence of inadequacy was estimate according to macro regions of the country (North, Northeast, Southeast, South and Midwest) and location of the households (urban or rural). Prevalence of inadequacy equal to or greater than 70% were observed for calcium among men and magnesium, vitamin A, and sodium among both sexes. Prevalence equal to or greater than 90% were found for calcium in women and vitamins D and E in both sexes. In general, the greatest risk groups of inadequate micronutrient intake were women and those living in rural areas and in the Northeast region. In the second paper, the prevalence of inadequacy was estimate according to income and education. Income was characterized by monthly household per capita income and education was defined by number of full years of study. Both variables were categorized into quartiles. Simple linear regression models and mutually adjusted were estimated to verify the independent association between nutrient intake and socioeconomic variables. The interactions between income and education were tested. Results indicated that most of nutrients inadequacy decreased with increasing income and education; however, the excessive intake of saturated fat and low fiber intake increased with both variables. Most of nutrients were independently associated with income and education, however, iron, vitamin B12 and sodium intake among women were only associated with education. The interaction between income and education were observed in the association with sodium intake in men, phosphorus in women and calcium in both sexes. The findings indicate that improvement of education is an important step in reaching an adequate nutrient intake in Brazil, besides the need to formulate economic strategies that would allow lower-income individuals to adopt a healthy diet. Our results also show a major challenge to public healthy actions in the nutrition area, with important inadequacies of intake in adult Brazilian population, particularly in the most vulnerable regions of the country.
185

Effects of Micronutrients on the status of HIV-infected African American Women

Graham, Veronica Alicia 01 January 2018 (has links)
Weight loss among HIV-infected African American women (AAW), results in the fall of the cluster of differentiation (CD4) cell count and an increase in the viral load. There are 48,126 HIV-infected AAW who reported weight loss within the first year. AAW who report more than 10% weight loss within the first year progress to AIDS due to a deficiency in micronutrients and poor linkage to care. The phenomenon that occurs with individuals living with HIV does not necessarily occur among individuals who have cancer, heart disease, or some other life-threatening illness, and this phenomenon indicates a direct threat to the individual's physical, mental, and social survival beyond the effects of chronic diseases. Using the health belief model in this study helped emphasize the physical change that occurs during weight loss among HIV-infected AAW. The research questions addressed if there was a direct correlation between the use of micronutrients and the decrease in weight, decrease in CD4 cell count, and the increase in viral load. The results of the multilinear regression revealed there was direct correlation between the use of micronutrients and the increase/maintain in weight, an increase in CD4 cell count, and a decrease in the viral load, thus promoting the need for more research and funding. The need to educate HIV-infected AAW on the use of micronutrients was evident. Providing research to providers on changes in standard of care for HIV-infected AAW would allow for an increase in the social, economic, and personal impact on the way an individual approaches care and treatment to prevent the progress to AIDS.
186

Wild vegetables and micronutrient nutrition : Studies on the significance of wild vegetables in women's diets in Vietnam

Ogle, Britta M. January 2001 (has links)
The principal aim has been to investigate the contemporary role and importance of edible wild plants in the diets of women in different agro-ecological regions of Vietnam. Field studies were undertaken in four villages in the Mekong Delta (MD) and the Central Highlands (CH) in 1995-1999. Data collection included rapid appraisal techniques, botanical identification, dietary assessments (7-day food frequency recall), anthropometry, blood sampling (haemoglobin, serum ferritin, serum retinol and C-reactive protein) and analysis of vegetable samples (dry matter, selected minerals and vitamins, tannins and phytic acid). A food variety analysis was used to test the adequacy of diets. The uses of over 90 wild plant species were documented, many with multiple functions as foods, medicines and livestock feeds. In the dietary assessment 29 species were reported. Most women used a combination of home produced, commercial and wild vegetables. A high 72 and 43% respectively of the vegetables consumed in the MD and CH sites were gathered (rainy season). They contributed significantly to micronutrient intakes, especially vitamin A, calcium, vitamin C and folate. They added considerably to food diversity and women with the most diverse diets had relatively adequate nutrient intakes. The species used and importance of wild plants varied considerably with region, season and ethnicity. The main conclusions are that edible wild plants continue to make important contributions to the nutrient intakes of women. If this is neglected in diet assessments our understanding of the overall dietary adequacy may be misinterpreted and much valuable knowledge of traditional food diversification may be lost. A food variety analysis can be a useful tool in identifying groups with inadequate diets. The dual role of many species as dietary components and in preventive health care deserves greater attention.
187

Infant Anemia and Micronutrient Status : Studies of Early Determinants in Rural Bangladesh

Eneroth, Hanna January 2011 (has links)
Anemia and micronutrient deficiencies in infancy are common in low-income settings. These are partly due to maternal malnutrition and may impair child health and development. We studied the impact of maternal food and micronutrient supplementation, duration of exclusive breastfeeding (EBF), growth and infection on infant anemia and micronutrient status. In the MINIMat trial in Matlab, Bangladesh, pregnant women were randomized to Early or Usual promotion of enrolment in a food supplementation program and to one of three daily micronutrient supplements. Capsules containing 400µg folic acid and (a) 30 mg iron (Fe30Fol), (b) 60 mg iron (Fe60Fol), (c) 30 mg iron and other micronutrients (MMS) were provided from week 14 of gestation. Capsule intake was assessed with the eDEM device recording supplement container openings. Blood samples (n=2377) from women at week 14 and 30 were analyzed for hemoglobin (Hb). Duration of EBF and infant morbidity was based on monthly maternal recalls. Infants were weighed and measured monthly. Blood samples (n=1066) from 6-months-old infants were analyzed for Hb and plasma ferritin, zinc, retinol, vitamin B12 and folate. In women, Hb increase per capsule reached a plateau at 60 Fe60Fol capsules, indicating that nine weeks of daily supplementation produced maximum Hb response. Anemia was common (36%) at capsule intakes >60 indicating other causes of anemia than iron deficiency. In infants, vitamin B12 deficiency prevalence was lower in the MMS (26.1%) than in the Fe30Fol group (36.5%), (p=0.003) and zinc deficiency prevalence was lower in the Usual than in the Early group. There were no other differential effects of food or micronutrient supplementation on infant anemia or micronutrient status. Infants exclusively breast-fed for 4-6 months had a higher mean plasma zinc concentration (9.9±2.3 µmol/L) than infants exclusively breast-fed for <4 months (9.5±2.0 µmol/L), (p< 0.01). No other differences in anemia, iron or zinc status were observed between EBF categories. Infection, low birth weight and iron deficiency were independent risk factors for infant anemia. Regardless of studied interventions, prevalence of anemia (43%), deficiency of zinc (56%), vitamin B12, vitamin A (19%) and iron (22%) in infancy was high and further preventive strategies are needed. / MINIMat
188

BORON NUTRITION OF BURLEY AND DARK TOBACCO

Frakes Mitchell, Laura Ann 01 January 2014 (has links)
The incidences of suspected Boron (B) deficiency have increased recently in Kentucky tobacco fields, potentially due to recent changes in management practices. The symptoms observed in the field include; hollow stalk, stunted growth, deformed or no bud formation, small slits on the lower leaf midrib and uncontrollable breaking of the midrib approximately two inches from the stalk. B is a micronutrient tobacco needs in minute amounts, however excessive additions of B could cause toxicity. The objectives of this work were to 1) establish critical points for B sufficiency, 2) describe and define B deficiency and toxicity symptoms and 3) develop field strategies to aid in the mitigation of B deficiency. A general nutrient response curve was generated utilizing solution culture experiments. The peak of the response curve appeared to occur at solution B concentration of 100 µM. Trace-levels of B contamination and small plant size in the solution culture limited the development of deficiency symptoms. Toxicity was observed at solution concentrations of 400 µM and above. Despite choosing sites with a history of B deficiency, deficiency symptoms were not observed during this study. Toxicity was observed when 0.56 kg B/ha or greater was applied as simulated transplant water treatments. No toxicity was observed when B was applied as a soil broadcast or foliar application. Recommendations are to apply B with caution as a broadcast application to avoid potential problems with toxicity. Additional research is required to refine the nutrient response curve and better understand B deficiency.
189

Absorção e mobilidade do boro em plantas de repolho e de couve-flor /

Alves, Adriana Ursulino. January 2009 (has links)
Resumo: Objetivou-se avaliar os efeitos da omissão de boro na solução de nutrientes e de doses de boro em aplicação foliar no crescimento e na nutrição, e estudar o tempo de absorção e a sua mobilidade em plantas de repolho 'Astrus' e couve-flor 'Verona'. Para isto, foram realizados na UNESP, Câmpus de Jaboticabal, oito experimentos com as plantas do repolho 'Astrus' e da couve-flor 'Verona' no período de fevereiro de 2007 até maio de 2008. Nas duas hortaliças, estudaram-se a omissão de boro em diferentes estádios de desenvolvimento e as doses de boro (0; 0,085; 0,170; 0,255 e 0,340 g L-1) via aplicação foliar. Em seguida, estudaram-se o tempo de absorção do boro aplicado via foliar (até 30 dias após aplicação) nas hortaliças e também compararam-se a mobilidade do boro marcado (10B) absorvido pelas raízes e pelas folhas, nas folhas emitidas após a sua aplicação. Em todos os experimentos, avaliaram-se as variáveis de crescimento, nutrição e de produção de matéria seca das plantas. Verificou-se, que o efeito da deficiência de boro ficou evidente no final do ciclo das hortaliças (terceiro estádio de desenvolvimento), causando maior diminuição na parte comercial das hortaliças. A adubação foliar com o micronutriente promoveu a máxima produção de matéria seca da parte comercial e da planta inteira do repolho 'Astrus', com pulverizações foliares de B nas doses de 0,224 e 0,240 g L-1, respectivamente, e esteve associada com o teor foliar de B de 15 e 14 mg kg-1. Na couve-flor 'Verona', a massa seca da parte comercial e da planta inteira aumentaram linearmente com as doses de boro, assim como o teor foliar que variou de 14 a 25 mg kg-1. O boro é absorvido lentamente pelas folhas do repolho 'Astrus', absorvendo 50% do B aplicado, próximo de 15 dias após sua aplicação e na couve-flor 'Verona' aos três dias e 12 horas após ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The effects of boron on cabbage and cauliflower plants were analyzed under the following approaches: (1) omitting boron from the nutrient solution at different stages of plant development; (2) Foliarly application of different doses of boron: 0, 0.085, 0.170, 0.255, and 0.340 g L-1; (3) Measuring the time necessary for boron to be absorbed by the plants when the boron fertilizer is foliarly applied; (4) Determining boron mobility in the plants by means of labeled boron (10B) supplied either via foliar fertilization or the fertilizer being directly applied to the soil. The effects of those procedures were evaluated in terms of plant growth, nutrition and productivity. The results showed that the effects of boron deficiency are more clearly felt at the end of the plant cycle so that the main effect is on plant commercial value. The doses of 0.224 and 0.240 g L-1 were those resulting in the highest commercial and the whole plant yields, respectively. These doses were found to be related with B levels in the plants of 15 and 14 mg kg-1. The commercial part and the whole plant of the 'Verona' cauliflower cultivar increased linearly with doses of boron. The foliar level of boron also increased linearly from 14 to 25 mg kg-1. Boron is slowly absorbed by the leaves of the 'Astrus' cabbage cultivar: it takes almost 15 days for 50% of the total applied to be absorbed. Cauliflower plants of the 'Verona' cultivar, on the other hand, absorbed a similar proportion in 3 days and 12 hours. It was observed that boron is immobile both in cauliflower and cabbage plants suggesting that boron fertilizers should be applied directly to the soil / Orientador: Renato de Mello Prado / Coorientador: Arthur Bernades Cecilio Filho / Banca: Cassio Hamilton Abreu Junior / Banca: Francisco Maximino Fernandes / Banca: Mara Cristina Pessôa da Cruz / Banca: Leila Trevizan Braz / Doutor
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Utilização de fertilizantes a base de fosfito e micronutrientes na cultura do melão / Utilization of fertilizers containing phosphite and micronutrients in the melon crop

Barreto, Norma Danielle Silva 08 February 2008 (has links)
Made available in DSpace on 2016-08-12T19:15:23Z (GMT). No. of bitstreams: 1 Norma Danielle Silva Barreto ok.pdf: 1964752 bytes, checksum: f7fb43203346f0133b607e44e7c44b7c (MD5) Previous issue date: 2008-02-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Despite the high technology utilized in the melon crop at the Assú-Mossoró fruit producer area, state of Rio Grande do Norte, with respect to most of the nutrients, chiefly the micronutrients, the doses applied are the same as those utilized in regions of completely different edaphoclimatic characteristics, and most of the time defined by the supplier companies. Considering this fact, a study was aimed at to evaluate the response of the melon crop to foliar applied ferlizers containing fosfito and micronutrients. The experiment was carried out on a Red Latossolo Eutrophic soil, at Santa Júlia farm, municipality of Mossoró, utilizing a factorial scheme in randomized complete blocks design with four replications. The tratments were the combinations of fertilizers (Fosfitotal®, Fosfitototal Multielementos® and MicroUFERSA) and doses (0, 0.75, 1.5, 2.25 and 3.0 kg ha-1). The fertilizers were foliar applied prior to the beginning of flowering, through three sprayings at ten days interval. The traits evaluated were number, mean weight, and yield of marketable fruits (domestic and export markets), refuse and total, as well as pulp firmness and thickness, shape ratio, soluble solids content, titratable acidity, and laef nutrient content. Soluble solids content was higher in fruits of plants sprayed with Fosfitotal®, however the contents of P, Mg, Cu, Zn, and Fe decreased with increasing doses of the fertilizer. Plants that received the MicroUFERSA fertilizer had higher Mg, K, P,Cu, Mn, and Zn contents in leaves, which might have caused their higher yields. The highest net income was obtained with MicroUFERSA applied at the rate of 1.50 kg ha-1 / Apesar da alta tecnologia utilizada na cultura do melão, no que diz respeito à maioria dos nutrientes, principalmente micronutrientes, as doses aplicadas no pólo fruticultor Assú-Mossoró, estado do Rio Grande do Norte, são as mesmas utilizadas em regiões com características edafoclimáticas completamente diferentes, sendo muitas vezes definidas pelas empresas comercializadoras dos insumos. Em razão disso, foi conduzido um estudo para avaliar a utilização de fertilizantes foliares contendo fosfito e micronutrientes na cultura do melão. O experimento foi conduzido em solo Latossolo Vermelho Eutrófico, em área pertencente à fazenda Santa Júlia, município de Mossoró, utilizando-se um esquema fatorial em blocos completos casualizados com quatro repetições. Os tratamentos consistiram das combinações de fertilizantes (Fosfitotal®, Fosfitototal Multielementos® e MicroUFERSA) e doses (0; 0,75; 1,5; 2,25 e 3,0 kg ha 1). Os fertilizantes foram aplicados via foliar antes do florescimento, através de três pulverizações espaçadas de dez dias. As características avaliadas foram número, peso médio e produtividade de frutos comercializáveis (mercados interno e externo), refugos e totais, bem como firmeza e espessura de polpa, relação de formato, teor de sólidos solúveis, acidez titulável e teor de nutrientes nas folhas. O teor de sólidos solúveis foi maior nos frutos das plantas pulverizadas com Fosfitotal®, mas os teores de P, Mg, Cu, Zn e Fe diminuíram com o aumento das doses deste fertilizante. As plantas de melão submetidas à aplicação de MicroUFERSA apresentaram maiores teores de Mg, K, P, Cu, Mn e Zn, resultando em maiores produtividades. A maior renda líquida foi obtida com a dose 1,50 kg ha-1 de MicroUFERSA

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