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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

The feasibility of implementing a point-of-use micronutrient fortification among African pre-school children : a pilot study / Ogunlade, Adebayo Olakunle

Ogunlade, Adebayo Olakunle January 2009 (has links)
Background The high prevalence of micronutrient deficiencies among South African preschool children reinforces the need for an intensified micronutrient malnutrition control strategy targeting children at home or in school. The use of recently developed micronutrient powders also known as "in-home fortification" or "point-of-use fortification" can be an effective long-term, sustainable approach in improving early childhood nutrition and cognitive developmental potential. However, before embarking on large-scale, long-term, point-of-use fortification trials, it is imperative to conduct external pilot trials in which the feasibility of implementing full-scale studies can be effectively assessed. Objective The objective of this study was to assess the feasibility of implementing a point-of-use micronutrient fortification trial among African preschool children, which would aid in pilot-testing the study design, logistics and implementation process as well as reveal limitations which can be addressed before the implementation of full-scale trials. Methods Preschool children (n = 151), aged 36 -79 months with haemoglobin concentration (Hb)<= 12.5 g/dL, from eight schools in a low socio-economic community were randomly assigned to an intervention (n = 76) and a control (n = 75) groups, both receiving breakfast maize-meal porridge, either with added micronutrient or placebo powder for 52 school days. Several process evaluation indicators (fidelity, dose delivered, dose received, reach, recruitment and context) were used to assess trial feasibility. Selected indicators of early childhood development (Hb concentration, anthropometric indices and cognitive function) were used to evaluate the outcome of the intervention within the context of a pilot study. Results The process evaluation results indicate that the various implementation components were delivered with high fidelity. Capacity development and strengthening of the front-line staff cognitive assessors and study assistants) was executed as planned. The point-of-use fortificant was well accepted among the children and the mean percentage of days the point-of-use fortificant or placebo was consumed (~85%) did not differ between the groups. There were significant increases in Hb concentration (p < 0.05) from baseline to follow-up in both the intervention [mean change: 0.38 g/dL (95% CI: 0.14, 0.61 g/dL)] and control [mean change: 0.57 g/dL (95% CI: 0.35, 0.80 g/dL)] groups, however, mean change did not differ significantly between the groups (p = 0.250). The intervention did not improve any of the anthropometric indices measured in the intervention group compared to control. However, there was a medium likelihood for practical significance for the two global cognitive scores assessed, nonverbal index [intervention effects: 7.20 (95% C!: 2.60,11.81); P = 0.002, effect size: 0.55] and mental processing index [intervention effects: 2.73 (95% CI: 0.25,5.70); P = 0.072, effect size: 0.36] on the Kaufman Assessment Battery for Children, second edition. Conclusion The feasibility of implementing a point-of-use micronutrient fortification trial was demonstrated among African preschool children with potential benefits of improving their cognitive function. The most important lessons learned from this trial that could help improve similar future large-scale trials included the recruitment and training of the most eligible front-line staff as well as identifying that the use of a simple field-friendly finger prick method to measure Hb concentration may not be sufficiently sensitive to show differences in iron status after the intervention. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2010.
42

Randomized comparison of efficacy, adherence, and acceptability of three multiple micronutrient supplements in Iranian infants

Kourosh Samadpour Unknown Date (has links)
Introduction The last national micronutrient survey of Iran showed that, in spite of a national supplementation program, the prevalence of anaemia, and zinc deficiency were 37.8% and 20% among 15-23 months old infants, respectively. Data show that more than 60% of infants do not consume supplements regular. Moreover, the current supplementation program does not provide a zinc supplement. Home fortification has been promoted as an alternative approach, where families are able to add micronutrients to home-made food for infants. The majority of efficacy trials of multiple micronutrient containing ‘Sprinkles’ powder and crushable ‘Foodlets’ tablets have been conducted in areas where maize-based complementary food is common. The potential effects of home fortification supplement in Iran are uncertain as the staple food is different (wheat and rice vs. maize in other trials) and acceptability of the Sprinkles and Foodlets is unknown. This thesis aim to assess efficacy, adherence, and acceptability of Sprinkles and Foodlets as compared with current supplement (Drops) on micronutrient status (iron, zinc, vitamin A and vitamin D) and growth in Iranian infants aged 6-18 month. Methods A total of 405 infants were recruited from Hashtgerd, 80 km west of Tehran, Iran; 43 were excluded due to not meeting the inclusion criteria. The infants were randomly assigned to receive daily supplementation of Sprinkles (n=120), Foodlets (n=121) or Drops (n=121) for four months. Sprinkles and Foodlets contain iron, zinc, vitamin A, vitamin D, folate, and multiple B vitamins similar except that levels of iron are higher in the Sprinkles group. Drops do not contain zinc, vitamin B12, or folate. The persons responsible for the laboratory test and data entry were blinded to randomization. Haemoglobin, serum ferritin, serum retinol, serum zinc, 25(OH)D concentration and anthropometric measures were assessed at baseline and four months. At each monthly phase of the follow-up, adherence to supplements and side-effects related to supplements were reported by mothers. Six focus group discussions assessed mother’s perceptions about the supplements. Within group change in means over 4 months intervention was examined by Student’s paired t-test. The within group changes in proportions were assessed using McNemar’s test. Change across the three treatment groups were compared using analysis of covariance. Ethical clearance was obtained from the ethics committee of both the University of Queensland in Australia and the Ministry of Health in Iran. Results Of the total 362 infants included in the study, 313 (86%) had complete anthropometric and haemoglobin data, and 301 infants (83%) also had both initial and final serum samples. There were no significant differences between the three groups for baseline data. Baseline data showed approximately one fourth of anaemic children had iron deficiency anaemia and 38% of infants were zinc deficient. The children had a relatively good baseline status for vitamin A, vitamin D and growth. After four months intervention mean haemoglobin increased significantly in the three groups. Serum ferritin concentration increased in the Drops group (p<0.001) and Sprinkles group (p<0.05). A significant improvement was seen in zinc status for the Sprinkles and Foodlets but not the Drops group. Mean percentage of adherence to Sprinkles, Foodlets, and Drops (total amount of supplement used divided by total amount expected to be used) was (90.4±17.25), (80.7±25.01), and (88.5±16.85) respectively. Vomiting was higher in the Foodlets compared to other groups (p<0.001). Staining of the teeth was higher in Drops than the other groups (P<0.001). Most mothers in the Sprinkles group (97.3%) preferred this supplement over current supplement whereas 87.2% of mothers in the Foodlet group preferred Foodlets over the current supplement. In the focus group discussions, mothers stated that the new supplements were more acceptable and easier to use compared to current supplement. However, they had some issues about the new supplements; for example, lack of appropriate food to add the Sprinkles or Foodlets. Conclusion The combination of multivitamins plus iron and zinc when added to wheat or rice-based complementary foods improved iron and zinc status. Combining iron and zinc in Sprinkles and Foodlets did not show negative effects on iron or zinc status. No differences were seen in efficacy of the Sprinkles and Foodlets on outcomes except a little higher improvement of iron status in Sprinkles and a slight higher weight gain of infants in the Foodlets group. According to this efficacy trial and formative study, Sprinkles had a higher acceptability in the study population and there are factors to encourage its use (easy to use, tasteless, containing all required vitamins and minerals, shape, easy to transfer, and stimulates appetite). The trial identified trade-offs in combining multiple micronutrients into a single delivery mechanism, with no benefit from addition of vitamins A and D on nutritional status in this sample of infants. We might consider different acceptability to Sprinkles in some regions by different cultural practices but in summary Sprinkles is likely to be the best option as an alternative choice to the current supplementation (Drops).
43

Prenatal food and micronutrient supplementation to malnourished women in Bangladesh : Effects, Equity, and Cost-effectiveness

Shaheen, Rubina January 2015 (has links)
Maternal nutrition is closely linked to child health and survival. In Bangladesh there is a high prevalence of undernutrition in the form of chronic energy deficiency [CED, Body Mass Index &lt;18.5 (kg/m2)] in women and low birth weight. The aims of this thesis are to explore women’s perceptions of maternal undernutrition, to analyse the association between prenatal food supplementation and birth weight (BW), to analyse whether food- and multiple micronutrient interventions generate pro-disadvantaged equity in child survival, and to examine whether an early prenatal invitation to food supplementation and multiple micronutrient supplements (MMS) represents value for money in infant survival compared to invitation to food supplementation at usual time combined with 60 mg iron and 400 µg folic acid (standard practice). The study on women’s perceptions (n=236) was nested into the MINIMat randomized trial where women (n=4436) were allocated to early (E), or usual (U) time of invitation to prenatal food supplementation and 30 mg iron with 400 µg folic acid, or 60 mg iron with 400 µg folic acid, or MMS. Live births (n=3625) were followed-up. The analyses of equity and cost-effectiveness were based on this trial. A cohort design (n=619) was employed for the analysis of food supplements and BW. Women perceived maternal undernutrition as a serious health problem and attached very low scores to CED in pregnancy. An average of four months of prenatal food supplementation increased BW by 118 g. An early invitation to prenatal food supplementation and MMS lowered mortality in children before the age of five years and reduced social disparity in child survival chances. An increment from standard practice to E-MMS averted one extra infant death at a cost of US$797 to US$907, and saved one extra life year at a cost of US$27 to US$30. High priority should be given to the nutritional status of pregnant women in societies where undernutrition and food insecurity occurs. Prenatal food supplementation has the potential to significantly increase BW, and an early initiation of prenatal food supplementation combined with MMS was considered cost-effective in lowering infant mortality and increase social equity in child survival chances.
44

Aplicação foliar de zinco na biofortificação de rúcula / Foliar application of zinc in the biofortification of arugula

Rugeles Reyes, Sergio Manuel 11 October 2017 (has links)
Submitted by SERGIO MANUEL RUGELES REYES null (smrugelesr@gmail.com) on 2018-01-04T14:31:39Z No. of bitstreams: 1 Dissertacao FINAL FINAL.pdf: 839997 bytes, checksum: 1ff42407d98ebf9f8e9ead2312027554 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-01-05T10:00:57Z (GMT) No. of bitstreams: 1 rugelesreyes_sm_me_jabo.pdf: 839997 bytes, checksum: 1ff42407d98ebf9f8e9ead2312027554 (MD5) / Made available in DSpace on 2018-01-05T10:00:57Z (GMT). No. of bitstreams: 1 rugelesreyes_sm_me_jabo.pdf: 839997 bytes, checksum: 1ff42407d98ebf9f8e9ead2312027554 (MD5) Previous issue date: 2017-10-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A deficiência de zinco atinge um terço da população mundial e uma estratégia para solucionar essa problemática é a biofortificação agronômica de hortaliças. A rúcula tem ganhado notoriedade nos últimos anos devido às suas propriedades nutricionais e boa aceitação pelos consumidores. Em razão do incremento no seu consumo, torna-se uma hortaliça folhosa com alto potencial para estudos de biofortificação agronômica com zinco, porém, ainda são poucas as pesquisas feitas a respeito. Assim, em um solo com alto teor do micronutriente, objetivou-se avaliar o efeito de aplicações foliares de zinco, em diferentes épocas, sobre parâmetros fisiológicos, produtivos e nutricionais de rúcula ‘Folha larga’, visando à biofortificação agronômica. O experimento foi instalado na UNESP, câmpus Jaboticabal e foram avaliados dois fatores: dose de Zn (0,5; 1 e 1,5 kg ha-1 de Zn) e épocas de aplicação (15 dias após a emergência - DAE, 20 DAE, 25 DAE, 15 e 20 DAE e 15, 20 e 25 DAE) mais um controle, que não recebeu aplicação de zinco. Observou-se que não houve efeito dos fatores nem da interação nas variáveis fisiológicas, assim como na altura, área foliar e massa fresca da parte aérea. Doses de Zn afetaram os teores de N, Mn e P, enquanto para Cu e Fe não foram encontrados efeitos significativos. Verificou-se que com aplicação de 1,5 kg ha-1 de Zn, feita aos 25 DAE, obteve-se maior teor de Zn nas folhas de rúcula, representando incremento de 279% em relação ao controle, denotando a efetividade de aplicações foliares de zinco como estratégia de biofortificação em rúcula. / Zinc deficiency affects a third of the world population and a strategy to solve this problem is agronomic biofortification of vegetables. Arugula has gained importance in recent years due to its nutritional properties and good acceptance by consumers. Due to the increase in its consumption, it becomes a leafy vegetable with high potential for studies of agronomic biofortification with zinc, however, few researches have been done about them. Thus, in a soil with high micronutrient content, the objective was to evaluate the effect of foliar zinc applications, at different times, on physiological, productive and nutritional parameters of 'Broad Leaf' arugula, aiming at agronomic biofortification. The experiment was realized at UNESP, Jaboticabal Campus and two factors were evaluated: Zn dose (0.5, 1 and 1.5 kg ha-1 of Zn) and times of application (15 days after emergence - DAE, 20 DAE, 25 DAE, 15 and 20 DAE, and 15, 20 and 25 DAE) plus one control, which did not receive zinc application. It was observed that there was no effect of the factors or the interaction in the physiological variables, as well as in the height, leaf area and fresh mass of the aerial part. Doses of Zn affected the contents of N, Mn and P, whereas for Cu and Fe no significant effects were found. It was verified that with the application of 1.5 kg ha-1 of Zn, realized at 25 DAE, a higher Zn content was obtained in the arugula leaves, representing an increase of 279% in relation to the control, showing the effectiveness of foliar applications of zinc as a biofortification strategy in arugula.
45

Absorção e mobilidade do boro em cultivares de algodão

Bogiani, Julio Cesar- [UNESP] 13 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-13Bitstream added on 2014-06-13T19:40:04Z : No. of bitstreams: 1 bogiani_jc_dr_botfca.pdf: 1367437 bytes, checksum: 8627008381df0562aa354eb688e4a659 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O boro é um micronutriente de grande importância para o crescimento e desenvolvimento das plantas. Este elemento tem baixa mobilidade no floema e é reconhecidamente o micronutriente cuja deficiência é mais comum no algodoeiro. Partindo-se da hipótese de existe diferença de resposta ao B entre cultivares de algodão, este trabalho teve como objetivo, estudar a absorção e mobilidade do boro disponibilizado via solução nutritiva, em três cultivares de algodão, bem como, a conseqüência de uma eventual deficiência do nutriente na fotossíntese das plantas. O experimento foi conduzido em condições de casa de vegetação e as plantas foram cultivadas em vasos contendo solução nutritiva. Os tratamentos foram constituídos de três cultivares de algodão (FMT 701, DP 604BG e FMX 993), e cinco doses de boro na solução nutritiva (0,0 – 2,5 – 5,0 – 10,0 e 20,0 μmol L-1). O delineamento experimental utilizado foi em blocos casualizados com quatro repetições em esquema fatorial com 3 cultivares x 5 doses. Foram feitas avaliações visuais dos sintomas de deficiência, durante todo o experimento, sendo os sintomas anotados e fotografados. As avaliações fisiológicas foram feitas quando as plantas atingiram o estádio de emissão do primeiro botão floral e foram repetidas após uma e quatro semanas após este estádio. As avaliações fitotécnicas e nutricionais foram feitas em quatro semanas, com a primeira iniciando uma semana após a o estádio de emissão do primeiro botão floral. Os resultados obtidos neste experimento levaram a concluir que: A época de aparecimento e a intensidade de sintomas de deficiência de boro entre cultivares de algodão é diferente. A cultivar DP604BG é inicialmente menos exigente em B, porém, há necessidade de maior disponibilidade de boro no meio nutritivo para evitar o aparecimento de deficiência. O crescimento do algodoeiro... / Boron is an micronutrient of great importance for growth and development of plants. This element has low mobility in the phloem and is known to the micronutrient whose deficiency is more common in cotton. Based on the hypothesis that there is difference of sensitivity to B between cotton cultivars, this work aimed to study the uptake and mobility of boron available in nutrient solution at three cotton cultivars, as well as the consequence of boron deficiency in the photosynthesis of plants. The experiment was conducted under greenhouse conditions and plants were grown in plots containing nutrient solution. The treatments were constituted of three cotton cultivars (FMT 701, DP 604BG and FMX 993), and five doses of boron in the nutrient solution (0.0 - 2,5 - 5.0 to 10.0 and 20.0 mmol L -1). The experimental design used was the completely randomized with four replications in outline factorial 3 cultivars x 5 doses. Evaluations were made of visual deficiency symptoms during all of experiment period and the symptoms recorded and photographed. Physiological evaluations were made when the plants reached the season of first flower bud and were repeated after one and four weeks after this season. Agronomic parameters and nutritional available were made in four weeks, with the first available starting one week after the season of first stage bud. Time of appearance and severity of symptoms of boron deficiency between cotton cultivars is different. Cultivar DP604BG is initially less boron requiring, but there is need of great availability boron in the nutrient solution to prevent the appearance of deficiency. The cotton growth was loss by boron deficiency regardless of differences of symptoms appearance, without deference between cultivars. The boron deficiency affect the physiological activity of three cotton cultivars
46

Efeito residual e reaplicação de boro na cultura do eucalipto (Clone I144) /

Celestrino, Thiago de Souza. January 2017 (has links)
Orientador: Salatiér Buzetti / Resumo: Os solos de Cerrado apresentam baixos teores de matéria orgânica e, sendo esta a principal fonte primária de boro (B), torna-se necessário o suprimento deste nutriente via adubação. Portanto, em plantios comerciais de eucalipto, é comum a adubação no sulco de plantio e até mesmo via foliar, durante a fase de implantação da cultura. Sendo assim, é importante verificar se a aplicação de B realizada inicialmente por meio de fontes com diferentes solubilidades é suficiente para atender as exigências da cultura ao longo do ciclo, ou se é necessária a reaplicação do elemento em cobertura. Objetivou-se com esse trabalho comparar o efeito residual das fontes de B aplicadas no sulco de plantio, assim como também a aplicação foliar e a reaplicação de B em cobertura na cultura do eucalipto (clone I144), tendo em vista o alto índice de bifurcação das árvores sem aplicação de B. O experimento foi conduzido na Fazenda Renascença, localizada no município de Três Lagoas/MS, com latitude 20o 34’ S e longitude 51o 50’ O e altitude de aproximadamente 305 m. O delineamento experimental foi blocos casualizados, com cinco repetições, em esquema fatorial, onde as parcelas foram subdivididas, perfazendo um 3 x 2 x 2, sendo o primeiro fator: 0 kg ha-1 de B; 1 kg ha-1 de B utilizando o fertilizante borogran (baixa solubilidade, 10% B), aplicado manualmente em filete contínuo no sulco de plantio; 1 kg ha-1 de B utilizando o fertilizante ácido bórico (alta solubilidade, 17% B), aplicado manualmente em f... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cerrado soils have low organic matter content, and this being the main primary source of boron (B), it is necessary to supply this element through fertilization. Therefore, in commercial eucalyptus plantations, it is common to fertilize in the planting groove and even via the foliar, during the implantation phase of the crop. Therefore, it is important to verify if the application of B carried out initially is sufficient to meet the crop requirements during the cycle, or if it is necessary to reapply the element under cover. The objective of this work was to compare the residual effect of the B sources applied to the planting groove, as well as the foliar application of the element and the reapplication of B in cover in the eucalyptus crop (clone I144), considering the high index of bifurcation in the treatments that did not receive the application of B. The experiment was conducted at Fazenda Renascença, located in the municipality of Três Lagoas/MS. The experimental design was randomized blocks, with five replications, in a factorial scheme, where the plots were subdivided, making a 3 x 2 x 2, being the first factor: 0 kg ha-1 of B; 1 kg ha-1 of B using borogran fertilizer (low solubility, 10% B), manually applied in continuous fillet in the planting groove; 1 kg ha-1 of B using boric acid fertilizer (high solubility, 17% B), manually applied in continuous fillet in the planting groove. Factorial 2 refers to the application or not of B via foliage. Two foliar applications o... (Complete abstract click electronic access below) / Doutor
47

Doses e modos de aplicação de boro na produção de mudas de nespereira / Dosages and modes of application of boron in the production of seedlings loquat tree

Penha, Estevan Teodoro Santana [UNESP] 23 February 2016 (has links)
Submitted by ESTEVAN TEODORO SANTANA PENHA null (estevaneafmuz@yahoo.com.br) on 2016-03-21T13:30:08Z No. of bitstreams: 1 Doses e modos de aplicação de boro na produção de mudas de nespereira - Estevan Teodoro Santana Penha.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-22T17:02:26Z (GMT) No. of bitstreams: 1 penha_ets_me_jabo.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5) / Made available in DSpace on 2016-03-22T17:02:26Z (GMT). No. of bitstreams: 1 penha_ets_me_jabo.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5) Previous issue date: 2016-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The loquat cultivation is increasing in Brazil and in the world and is an important source of income for small farms, however, the production of seedlings can be an obstacle to its expansion. Thus the aim of this study was to evaluate Boron reflection on the quality of loquat seedlings, and the place of supply to plants parent by determining the most effective application method in this process. There were four boron doses (0, 2.5, 5.0 and 7.5 mg dm-3) and two application sites (soil and leaf). The use of boron instock plants improves the root system of plants from cuttings, the most efficient foliar application than the soil. The application of this micronutrient promotes balance between root / shoot, ensuring the formation of a balanced changes, given that the leaf supply increases the volume of the stake roots. Therefore the supply of boron to headquarters makes the process effectively, reducing cost, optimizing time and assuring the quality of fruit seedlings. / O cultivo de nêsperas vem aumentando no Brasil e no mundo, sendo uma importante fonte de renda para pequenas propriedades, no entanto, a produção de mudas pode ser um gargalo de sua expansão. Dessa forma o objetivo do presente trabalho foi avaliar o reflexo do boro na qualidade das mudas de nespereira, bem como o local de seu fornecimento às plantasmães determinando-se o modo de aplicação mais eficiente neste processo. Foram utilizadas quatro doses de boro (0; 2,5; 5,0 e 7,5 mg dm-3 ) e dois locais de aplicação (no solo e foliar). A utilização de boro nas plantas-matrizes melhora o sistema radicular das mudas obtidas por estaquia, sendo a aplicação foliar mais eficiente do que via solo. A aplicação deste micronutriente promove o equilíbrio entre raiz/parte aérea, garantindo a formação de uma muda equilibrada, haja vista que o fornecimento foliar aumenta o volume de raízes da estaca. Portanto o fornecimento de boro às matrizes torna o processo eficaz, reduzindo custo, otimizando tempo e garantindo a qualidade das mudas frutíferas.
48

Nitrogênio e boro no cultivo de couve-flor ‘Verona CMS’ no médio norte mato-grossense

Fernandes, Solange Ossuna 30 July 2014 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-03-20T20:44:06Z No. of bitstreams: 1 DISS_2014_Solange Ossuna Fernandes.pdf: 5309319 bytes, checksum: 27262f2dd082e3af96047c24419b6983 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-10T19:02:31Z (GMT) No. of bitstreams: 1 DISS_2014_Solange Ossuna Fernandes.pdf: 5309319 bytes, checksum: 27262f2dd082e3af96047c24419b6983 (MD5) / Made available in DSpace on 2018-04-10T19:02:31Z (GMT). No. of bitstreams: 1 DISS_2014_Solange Ossuna Fernandes.pdf: 5309319 bytes, checksum: 27262f2dd082e3af96047c24419b6983 (MD5) Previous issue date: 2014-07-30 / CAPES / A couve-flor é considerada uma olerícola de grande importância econômica, especialmente para pequenos produtores, por ser uma cultura rentável em pequenas áreas. No Brasil, as principais regiões produtoras são Sudeste e Sul. O tamanho e a qualidade de sua cabeça são os aspectos mais importantes à sua comercialização, sendo influenciados pelos nutrientes absorvidos durante o ciclo da cultura, destacando-se, entre eles, o nitrogênio e o boro. O nitrogênio (N) é o nutriente que mais influencia o crescimento das plantas, pois está presente na composição das mais importantes biomoléculas, tais como ATP, NADH, NADPH, clorofila, proteínas e inúmeras enzimas. Em couve-flor, a deficiência deste nutriente influencia de forma significativa as variáveis vegetativas da planta, diminuindo o número de folhas, a altura da planta, o diâmetro da haste, a área foliar e a matéria seca. A fertilização nitrogenada acelera o desenvolvimento da planta, aumentando a produtividade e o diâmetro da cabeça de couve-flor, já que o N é responsável pelo desenvolvimento vegetativo rápido e vigoroso da planta, o que está associado ao bom desenvolvimento da inflorescência. O boro (B) é essencial para o crescimento celular, principalmente nas partes jovens da planta, como gemas, meristemas apicais e estruturas reprodutivas, sendo essencial também para a estrutura e função da parede celular, pois estabiliza a rede péctica e regula o tamanho do poro da parede celular. A adubação com B para brássicas no Brasil é recomendada com frequência, visto que os resultados existentes indicam resposta positiva para utilização deste micronutriente, que há muito já teve sua essencialidade comprovada, apesar de sua função primária não ter sido totalmente esclarecida. As doses de fertilizantes atualmente indicadas subestimam a real necessidade da cultura nas diferentes regiões produtoras do país, o que dificulta a obtenção de altas produtividades e padrões comerciais. Com isso, o objetivo deste estudo foi avaliar a influência de N e B no cultivo de couve-flor ‘Verona CMS’. / Cauliflower is considered a greenery of great economic importance, especially to smallholders, to be a culture profitable in small areas. In Brazil, the main producing regions are South and Southeast. Curd size and quality are the most important aspects of your marketing, being influenced by nutrients absorbed during the crop cycle, standing out, among then, nitrogen and boron. Nitrogen (N) is the nutrient that most affects plant growth, because it is present in the composition of the most important biomolecules, such as ATP, NADH, NADPH, chlorophyll, proteins and numerous enzymes. In cauliflower, N deficiency affects the vegetative plant variables, decreasing number of leaves, plant height, stem diameter, leaf area, and dry matter. Nitrogen fertilization accelerates the development of the plant, increasing yield and cauliflower curd diameter, whereas N is responsible for fast and vigorous vegetative developing, that is associated with good development of the blossom. Boron (B) is essential for cellular growth, mainly in young plant parts like buds, apical meristems, and reproductive structures, being essential for cell wall structure and function, because stabilizes pectic network and regulates de pore size of cell wall. Boron fertilization for Brassicacea in Brazil is often recommended, whereas an existents result indicates positive response for this micronutrient utilization, which has long since had its essentiality proven, although their primary function is not clarified. Fertilizers levels currently recommended underestimate the real need of culture in different places cultivation, making it difficult to obtain high productivity and trade patterns. Therefore, the aim of this study was evaluate N and B influence in the cultivation of cauliflower ‘Verona CMS’.
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Efeito residual e reaplicação de boro na cultura do eucalipto (Clone I144) / Residual effect and reapplication of boron in eucalyptus (Clone I144)

Celestrino, Thiago de Souza 21 December 2017 (has links)
Submitted by Thiago de Souza Celestrino null (thiagocelestrino@yahoo.com.br) on 2018-02-15T23:10:09Z No. of bitstreams: 1 THIAGO DE SOUZA CELESTRINO_tese_corrigida-1.pdf: 1849166 bytes, checksum: db9e21bb2d41dddb2133285c68c4f044 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-02-16T12:58:18Z (GMT) No. of bitstreams: 1 celestrino_ts_dr_ilha.pdf: 1957549 bytes, checksum: 4cf4e781aeff7c17a0ee39f00b69d05b (MD5) / Made available in DSpace on 2018-02-16T12:58:18Z (GMT). No. of bitstreams: 1 celestrino_ts_dr_ilha.pdf: 1957549 bytes, checksum: 4cf4e781aeff7c17a0ee39f00b69d05b (MD5) Previous issue date: 2017-12-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os solos de Cerrado apresentam baixos teores de matéria orgânica e, sendo esta a principal fonte primária de boro (B), torna-se necessário o suprimento deste nutriente via adubação. Portanto, em plantios comerciais de eucalipto, é comum a adubação no sulco de plantio e até mesmo via foliar, durante a fase de implantação da cultura. Sendo assim, é importante verificar se a aplicação de B realizada inicialmente por meio de fontes com diferentes solubilidades é suficiente para atender as exigências da cultura ao longo do ciclo, ou se é necessária a reaplicação do elemento em cobertura. Objetivou-se com esse trabalho comparar o efeito residual das fontes de B aplicadas no sulco de plantio, assim como também a aplicação foliar e a reaplicação de B em cobertura na cultura do eucalipto (clone I144), tendo em vista o alto índice de bifurcação das árvores sem aplicação de B. O experimento foi conduzido na Fazenda Renascença, localizada no município de Três Lagoas/MS, com latitude 20o 34’ S e longitude 51o 50’ O e altitude de aproximadamente 305 m. O delineamento experimental foi blocos casualizados, com cinco repetições, em esquema fatorial, onde as parcelas foram subdivididas, perfazendo um 3 x 2 x 2, sendo o primeiro fator: 0 kg ha-1 de B; 1 kg ha-1 de B utilizando o fertilizante borogran (baixa solubilidade, 10% B), aplicado manualmente em filete contínuo no sulco de plantio; 1 kg ha-1 de B utilizando o fertilizante ácido bórico (alta solubilidade, 17% B), aplicado manualmente em filete contínuo no sulco de plantio. O fatorial 2 se refere à aplicação ou não de B via foliar. Foram realizadas duas aplicações foliares de B até o primeiro ano de idade da cultura. Em cada aplicação foi utilizado ácido bórico a 0,5 % na calda com volume de 250 L ha-1. O último fator 2, se refere às subparcelas que receberam ou não a reaplicação de B aos 34 e 46 meses após o plantio, na projeção da copa, utilizando o fertilizante ácido bórico na dose de 1 kg ha-1 de B em cada aplicação. Para a aplicação de 1 kg ha-1 de B no plantio, há a necessidade da reaplicação do nutriente em cobertura, influenciando positivamente o seu teor no solo, no estado nutricional, produtividade de madeira, transferência de B ao solo e concentração no folhedo. As reaplicações de B também promoveram o maior acúmulo do nutriente no tronco, reduzindo, assim, a eficiência de uso do B na produção de madeira. Embora houve maior efeito residual de B no solo, em virtude da aplicação do borogran, as fontes de B se comportaram de modo semelhante para as mensurações de produtividade de madeira, concentração foliar, qualidade do fuste e transferência ao solo. Cabe destacar que, mesmo sendo uma dose considerada baixa (1 kg ha-1 de B), sua aplicação, bem como as aplicações foliares de B, reduziram a porcentagem de bifurcação das árvores. A densidade básica da madeira e o acúmulo de B nas frações (galhos e folhas) não foram influenciados pelo efeito residual das fontes de boro, assim como as aplicações foliares e reaplicações em cobertura. / Cerrado soils have low organic matter content, and this being the main primary source of boron (B), it is necessary to supply this element through fertilization. Therefore, in commercial eucalyptus plantations, it is common to fertilize in the planting groove and even via the foliar, during the implantation phase of the crop. Therefore, it is important to verify if the application of B carried out initially is sufficient to meet the crop requirements during the cycle, or if it is necessary to reapply the element under cover. The objective of this work was to compare the residual effect of the B sources applied to the planting groove, as well as the foliar application of the element and the reapplication of B in cover in the eucalyptus crop (clone I144), considering the high index of bifurcation in the treatments that did not receive the application of B. The experiment was conducted at Fazenda Renascença, located in the municipality of Três Lagoas/MS. The experimental design was randomized blocks, with five replications, in a factorial scheme, where the plots were subdivided, making a 3 x 2 x 2, being the first factor: 0 kg ha-1 of B; 1 kg ha-1 of B using borogran fertilizer (low solubility, 10% B), manually applied in continuous fillet in the planting groove; 1 kg ha-1 of B using boric acid fertilizer (high solubility, 17% B), manually applied in continuous fillet in the planting groove. Factorial 2 refers to the application or not of B via foliage. Two foliar applications of B were carried out until the first year of culture. In each application, 0,5% boric acid was used in the syrup with a volume of 250 L ha-1. The last factor 2, refers to the subplots that received or not the reapplication of B at 34 and 46 months after planting, in the crown projection, using the boric acid fertilizer at the dose of 1 kg ha-1 of B in each application. For the application of 1 kg ha-1 of B in the plantation, there is a need for reapplication of the covering element, positively influencing the soil element content, nutritional status of the crop, wood productivity, soil B transfer and soil concentration. element not leafed. The reapplications of B also promoted the greater accumulation of the element in the trunk of wood, thus reducing the efficiency of use of B in the production of wood. Although there was a greater residual effect of B in the soil due to borogran application, the sources of B behaved similarly to the measurements of wood productivity, leaf concentration, stem quality and soil transfer. It should be noted that even though a dose considered low (1 kg ha-1 of B), its application, as well as the foliar applications of B, reduced the percentage of bifurcation of the trees. There is a higher concentration of B in lower leaves of the crown when compared to the upper leaves, indicating, therefore, the low mobility of the element in the phloem. The basic wood density and the accumulation of B in the fractions (branches and leaves) were not influenced by the residual effect of the boron sources, as well as the foliar applications and reapplication of the cover element. / FAPESP: 14/03387-6
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Efeito do ácido indolbutírico, boro e armazenamento no enraizamento de estacas de azaleia cultivadas em vaso / Effect of indolebutyric acid, boron and storage on rooting of potted azalea cuttings

Bezerra, Amanda Kelly Dias 20 December 2017 (has links)
Submitted by Amanda Kelly Dias Bezerra (amanda_kely_@hotmail.com) on 2018-04-18T01:22:33Z No. of bitstreams: 1 Amanda Bezerra - Tese.pdf: 1415728 bytes, checksum: ba537c08fc169bf2c062166468a12d50 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-04-18T17:34:31Z (GMT) No. of bitstreams: 1 bezerra_akd_dr_jabo.pdf: 1415728 bytes, checksum: ba537c08fc169bf2c062166468a12d50 (MD5) / Made available in DSpace on 2018-04-18T17:34:31Z (GMT). No. of bitstreams: 1 bezerra_akd_dr_jabo.pdf: 1415728 bytes, checksum: ba537c08fc169bf2c062166468a12d50 (MD5) Previous issue date: 2017-12-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A azaleia (Rhododendron simsii) é uma das principais plantas ornamentais cultivadas em vaso no Brasil; embora a propagação comercial seja realizada por estaquia, os produtores relatam que alguns cultivares, como a ´Otto´, apresentam dificuldades no enraizamento. Devido a isto, os objetivos desta pesquisa foram: (i) avaliar o efeito do ácido indolbutírico (AIB) e do boro aplicados em estacas e (ii) determinar o período máximo de armazenamento de estacas a frio, mantendo alta porcentagem e qualidade do sistema radicular durante o processo de enraizamento de estacas dos cultivares de azaleia Otto e Terra Nova. Os estudos foram desenvolvidos no município de Holambra, SP, na propriedade comercial “Sleutjes Azaleias”, e as avaliações foram realizadas no Laboratório de Sementes de Plantas Hortícolas do Departamento de Produção Vegetal, Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal. Em todos os estudos, foi utilizado o delineamento experimental inteiramente casualizado. No primeiro experimento, realizou-se o tratamento das estacas com AIB e boro; os tratamentos foram arranjados em esquema fatorial 4 x 4 (doses de AIB: 0, 1000, 2000 e 3000 mg L-1 e boro: 0; 2,5; 5,0 e 7,5 mg L-1); foram quatro repetições e 10 estacas por parcela. No segundo experimento, o armazenamento se deu com a coleta das estacas herbáceas de plantas cultivadas em vasos da área de produção apresentando 10 cm de comprimento; em seguida, foram acondicionadas em embalagens de polipropileno e armazenadas em câmara fria (10±1 °C) por diferentes períodos (0, 7, 14, 21, 28 e 35 dias) com quatro repetições e 10 estacas por parcela. Os experimentos foram avaliados após 42 dias do estaqueamento, anotando-se: porcentagem de enraizamento, número de raízes; comprimento médio e total, quantidade de matéria seca, volume, área superficial e diâmetro médio das raízes e, no segundo experimento, foram acrescidos às análises já citadas a avaliação dos teores de boro na folha e no substrato. Concluiu-se que a porcentagem de enraizamento das estacas não foi influenciada pelo AIB e nem pelo boro, porém, as estacas tratadas com 2000 mg L-1 de AIB, apresentaram melhor qualidade do sistema radicular; o armazenamento das estacas teve influencia negativa no enraizamento de estacas de ‘Otto’ e positiva em estacas de ‘Terra Nova’. / Azalea (Rhododendron simsii) is one of the main ornamental plants cultivated in pots in Brazil; although the commercial propagation is carried out by cuttings, the producers report that some cultivars, like 'Otto', present difficulties in rooting. Due to this, the objectives of this research were: (i) to evaluate the effect of indolbutyric acid (IBA) and boron applied on cuttings and (ii) to determine the maximum period of cold storage of cuttings, maintaining high percentage and quality of the root system during the rooting process of cuttings of the azalea cultivars Otto and Terra Nova. The studies were developed in Holambra city, SP, in the commercial property "Sleutjes Azaleias" and the evaluations were carried out in the Laboratory of Seeds of Vegetable Plants of the Plant Production Department, São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal. In all the studies the experimental design was completely randomized. The treatments were arranged in a 4 x 4 factorial scheme (doses of IBA: 0, 1000, 2000 and 3000 mg L-1 and boron: 0; 2,5 5,0 and 7,5 mg L-1); were four replicates and 10 cuttings per plot. In the second experiment, storage was carried out by collecting the herbaceous cuttings of plants grown in pots at the production area, 10 cm long, then packed in polypropylene containers and stored in a cold room (10 ± 1 °C) for different periods (0, 7, 14, 21, 28 and 35 days) with four replications and 10 cuttings per plot. The experiments were evaluated after 42 days of cutting, recording: rooting percentage, number of roots; the mean and total length, dry mass, volume, surface area and mean root diameter, and in the second experiment, the evaluation of boron levels in the leaf and in the substrate was added to the already mentioned analyzes. It was concluded that the percentage of rooting of the cuttings was not influenced by the IBA and boron, but the cuttings treated with 2000 mg L-1 of AIB showed better root system quality; the storage of cuttings had a negative influence on the rooting of 'Otto' cuttings and positive on 'Terra Nova' cuttings. / 152735/2014-1

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