Made available in DSpace on 2014-06-11T19:26:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-25Bitstream added on 2014-06-13T20:15:17Z : No. of bitstreams: 1 henriques_ab_me_assis.pdf: 2471520 bytes, checksum: a3c0b7b7adfaaad3514c1ba7dde5ab84 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esta pesquisa se insere dentro da bibliografia especializada sobre a agricultura no Brasil, especialmente no Estado de São Paulo, a partir da segunda metade do século XIX, início do século XX. Um de seus objetivos é ressaltar as propostas de modificação ou modernização da agricultura em São Paulo dentro deste período, em contraposição, ou substituição aos métodos e técnicas agrícolas considerados tradicionais e efetuados historicamente na agricultura brasileira. É dentro da Revista Agrícola paulista (1895-1907) que essas propostas foram suscitadas por dezenas de pessoas, escritores, agrônomos, grandes fazendeiros, políticos, e outros. As propostas de modificação agrícola giravam em torno de diferentes assuntos, mas sempre interligados, como: diversificação da agricultura, adubação química e natural, cultura intensiva do solo, mão-de-obra, povoamento e colonização, instalação de núcleos coloniais dentro dos moldes da moderna agricultura então desejada, instrução agrícola por meio de campos de experiências e demonstração, ensino agrícola para diferentes graus, a mecanização da lavoura, o que era chamado na época de Moderna Agricultura, em substituição ao que era considerado como agricultura rotineira ou atrasada, praticada deste o início da agricultura no Brasil / This research inserts itself into the historical analyses upon agriculture in Brazil, especially in the State of São Paulo, from around late XIX century and beginning of the XX century on. One of its goals is to stand out the agricultural modification proposals in São Paulo during that period, in opposition or substitution for the agricultural methods and techniques considered to be traditional, and historically effectuated in Brazilian agriculture. It was within the publication Revista Agrícola (São Paulo, 1895-1907) that such proposals were raised by dozens of people, publicists, agronomists, major farmers, politicians, among others. The agricultural modification proposals turned around different subjects, but always holding a connection, such as: agriculture diversification, natural or chemical manuring, intensive soil culture, labor, population and colonization, installation of colonial areas attending the desired patterns of modern agriculture by then, agricultural instruction through experience and demonstration fields, agricultural education for different levels, farming mechanization, which was called Modern Agriculture by that time, in substitution for what was considered to be routine and outdated agriculture, practiced since the beginning of agriculture in Brazil

Made available in DSpace on 2014-06-11T19:32:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-01Bitstream added on 2014-06-13T19:03:13Z : No. of bitstreams: 1 temoteo_as_dr_botfca.pdf: 1080395 bytes, checksum: af697e1f5d8f0fa69c0d419ec68872d0 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / A cafeicultura expandiu-se para áreas consideradas pouco aptas ao seu desenvolvimento e o cafeeiro Conilon tem apresentado características de adaptações para tais áreas. Nessas áreas, a salinidade aliada à deficiência hídrica apresentam restrições para cultivos de certas espécies ou cultivar, interferindo no crescimento e desenvolvimento de culturas comerciais. O objetivo deste estudo foi avaliar de forma comparativa os efeitos da salinidade aliada à disponibilidade hídrica do solo, em cultivares de café Conilon na fase inicial de crescimento, por meio de variáveis fisiológicas e nutricionais. O experimento foi desenvolvido em ambiente protegido em área experimental do Departamento de Engenharia Rural da FCA- UNESP, Botucatu-SP, no delineamento estatístico de blocos casualizados com duas cultivares de Conilon (clones 120 e 14), quatro níveis de salinidade no solo (0,0; 2,0; 4,0 e 6,0 dS m-1) e dois teores de água no solo (50% e 70% da água disponível no solo - AD), com 4 repetições, totalizando 64 parcelas, com um vaso e uma planta. Aos 165 dias, as mudas foram transplantadas para vasos com capacidade de 10 litros, mantidas com teor de água no solo próximo a capacidade de campo por 15 dias. Atingindo os níveis... / Coffee production has expanded to areas considered unsuitable to its development. Conilon coffee plant has shown adaptation characteristics for such areas where salinity combined to water deficit restrict crops of certain species or cultivar, interfering in the growth and development of commercial crops. This study aimed to compare the effects of salinity and soil water availability on Conilon coffee cultivars in the initial phase of the development through physiological and nutritional variables. The experiment was carried out in a protected environment of an experimental area of the Department of Rural Engineering of FCA-UNESP, Botucatu-SP, in a random block statistical design with two Conilon cultivars (clones 120 and 14), four levels of soil salinity (0.0; 2.0; 4.0 and 6.0 dS m-1) and two water contents in the soil (50% and 70% of available water in the soil – AW) and four replications, totalizing 64 plots with a vase and a plant. At 165 days, the seedlings were transferred to 10-liter vases, and the soil water content was kept almost at field capacity for 15 days. The vases were weighed daily, and water was replaced until pre-determined levels when they reached (50% and 70% of AW). Growth evaluations (leaf area, stem diameter and stem height) were done at (0, 20, 40, 60, 80, 100, 120, 140, 160 and 180 days), and 20 days after the differentiation of water treatments (DAT) in the soil, measurements were done. For relative water content and leaf water potential, (30, 60, 90, 120, 150 and 180 DAT) were taken into consideration. At the end of the experiment (180 DAT), the number of plagiotropic branches was counted; and at the time of the experiment, expanded leaves of the medial region were collected for the... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:35:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-18Bitstream added on 2014-06-13T20:45:46Z : No. of bitstreams: 1 tozzi_fro_dr_botfca.pdf: 12408119 bytes, checksum: ae3d91b6007ad3064d0e253ea2ee969a (MD5) / O dióxido de carbono é um dos principais gases de efeito estufa e há previsões de que a concentração na atmosfera irá dobrar até o final do século. O aumento da concentração de CO2 do ar contribui, sobretudo, para o aumento da temperatura global e, além disso, o gás exerce efeito direto sobre as plantas. Com o objetivo de estudar o efeito do aumento da concentração de CO2 sobre o cafeeiro e sobre a ferrugem do cafeeiro (Hemileia vastatrix), plantas foram cultivadas a campo, em estufas de topo aberto com e sem adição de CO2 em quatro experimentos. Os tratamentos foram constituídos dos níveis de CO2 ambiente (433 ppm) e, aproximadamente 508 ppm. Foram inoculadas mudas de cafeeiros das cultivares Catuaí (suscetível à ferrugem) e Obatã (resistente), nas quais foram avaliados os parâmetros de severidade e incidência da doença. A severidade foi menor no tratamento com maior concentração de CO2 para a cultivar Catuaí, indicando diminuição da doença em função do aumento do CO2. Para a cultivar Obatã, o aumento do gás não teve efeito na doença. Por outro lado, ambas as cultivares apresentaram incremento no diâmetro do caule e altura de plantas no tratamento com adição de CO2 / Carbon dioxide is a major greenhouse gas and there are predictions that its atmosphere concentration will double by the end of the century. CO2 air concentration increase contributes, mainly, to global temperature rise, moreover the gas exerts a direct effect on agriculture. In order to study the effect of air CO2 increased concentration on coffee and coffee leaf rust (Hemileia vastatrix) development, plants were grown, under field conditions, in open top chambers in four experiments. The treatments consisted of ambient CO2 levels (433 ppm) and approximately 508 ppm. Cultivar Catuaí (susceptible to rust) and Obatã (resistant) coffee seedlings were inoculated and evaluated through disease severity and incidence parameters. Severity was lower at higher CO2 for Catuaí, indicating decreased disease due to increased CO2. Elevated gas concentration had no effect on disease for cultivar Obatã. Moreover, both cultivars showed an increase, stem diameter and plant height at CO2 addition treatment

Made available in DSpace on 2015-01-26T13:21:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-29Bitstream added on 2015-01-26T13:30:58Z : No. of bitstreams: 1 000806768.pdf: 1210762 bytes, checksum: 0a35a96fc111ab1c7cf5c145b4c49b94 (MD5) / Na busca por novos tratamentos de alimentos contra a contaminação por pragas e microrganismos, o ozônio tem se tornado uma alternativa eficiente na redução destes agentes de deterioração, porém, a sua atuação sobre os tecidos vegetais também pode comprometer a qualidade do produto ozonizado. O presente trabalho tem o objetivo avaliar a qualidade do café arábica, lavado em diferentes tempos à uma dose constante de ozônio, e submetido a diferentes tempos de secagem e de armazenamento. Nos tratamentos foram utilizados 2 kg de café da roça por amostra, acondicionados em sacos de malhas plásticas de 1.5 x 0.5 cm, colocadas no tanque do aparelho ozonizador até completar o volume de 105 L. Em seguida, iniciou-se a ozonização mantendo as amostras submersas por diferentes períodos 0 min, 5min, 10min, 20 min e 30 min, com frequente agitação da água e taxa constante de ozônio solubilizado. Após cada tratamento, as amostras de café foram colocadas para secar, em bancadas suspensas, em dois ambientes: expostas ao sol, em condições naturais, e no interior de câmara climatizada com temperatura de 32°C e umidade relativa de 80%. Após a secagem, foram realizadas as análises de qualidade (contagem de fungos, condutividade elétrica, acidez graxa, lixiviação de potássio, açúcar total e redutor, compostos fenólicos totais e análise sensorial). O material oriundo das duas secagens foi armazenado em sacos plásticos no interior do laboratório, durante o período de seis meses, quando foram repetidas as análises de qualidade. O delineamento foi inteiramente ao acaso, com cinco tempos de ozonização 0, 5, 10, 20, 30 min e quatro repetições, sendo utilizada a análise de variância em três momentos: Após a ozonização, após a secagem e após o armazenamento. Para avaliar o comportamento dos diferentes tempos de ozonização, os dados de contagem de fungos foram avaliados ... / New treatments for food have been researched to control contamination against pests and microorganisms, in this context ozone has become an effective alternative to reduce these agents of deterioration, however its effect on plant tissues may also compromise the quality of the ozonated product. The aims of this study was to evaluate the quality of Arabica coffee, washed at different intervals of time in a constant dose of ozone, and subjected to different times if drying and storage. In each Treatment were used 2 kg of coffee per sample, packed in plastic bags with mesh sized 1.5 x 0.5 cm, placed in the tank ozonizer device until reach the volume of 105 L. In sequence, the ozonation started, keeping the samples immersed for different periods of time 0 min, 5 min, 10 min, 20 min and 30 min, with constant agitation of the water and constant solubilized ozone rate. After completing each treatment, the coffee samples were left to dry on suspended stands in two kinds of environments: exposed to sun under natural conditions, and within acclimatized chamber at 32 °C and 80% relative humidity. Immediately after drying, the quality analysis were performed (microbiological analysis, electrical conductivity, fat acidity, potassium leaching, total sugar and reducer, total of phenolic compounds and sensory analysis). In order to evaluate a possible latent effect of ozonation on the quality of the coffee beans, the material from the two drying process was stored in plastic bags inside the laboratory, for six months, and then the quality analysis ...

La plupart des espèces végétales sont des polyploïdes récents ou anciens. L’allopolyploïdisation qui résulte d’une hybridation interspécifique couplée à une duplication génomique joue un rôle fondamental dans l’évolution des plantes. Elle provoquerait des changements de l’organisation du génome et de la régulation de l’expression des gènes qui seraient à l’origine de nouvelles aptitudes de ces plantes. Dans ce contexte, l’étude des mécanismes de conciliation des réseaux parentaux de régulation des gènes semble essentielle pour définir leur rôle dans la variation de l’expression des gènes. Le genre Coffea, composé d’espèces diploïdes pouvant s’hybrider et d’une espèce allotétraploïde C. arabica, constitue un modèle approprié pour cette étude. L’allopolyploïde présente deux sous-génomes homéologues peu différenciés, provenant de l’hybridation de C. eugenioides et C. canephora. A l’inverse de ses espèces parentales qui se caractérisent par des écosystèmes différents et d’amplitude thermique faible, C. arabica se développe en tolérant des variations de température plus importantes. Ce travail a consisté à étudier chez C. arabica les conséquences de l’hybridation sur la variation de l’expression et de la régulation des gènes et à analyser la variation de l’expression des gènes homéologues et son implication dans les capacités adaptatives. L’expression et la régulation des gènes au sein d’hybrides F1 entre C. canephora et C. eugenioides ont été analysées en utilisant la technologie RNA-seq. L’étude de ces hybrides a montré que les espèces parentales se distinguent par une proportion importante de divergences de trans-régulation. Pour 77% des gènes différemment exprimés entre les espèces parentales et les hybrides, le niveau d’expression de l’hybride est comparable à celui de l’une des espèces parentales, c’est le phénomène de «level expression dominance». L’analyse de l’expression allélique spécifique a permis de caractériser la régulation de l’expression des gènes ; les deux allèles sont exprimés, avec exceptionnellement un biais en faveur d’un génome. L’expression des gènes est déterminée par des combinaisons complexes de divergences de cis-régulation des espèces parentales et des effets entrecroisés de leurs facteurs de trans-régulation. Le niveau d’expression des gènes dépend de la sur ou sous-régulation simultanée des deux allèles et en particulier, de l’asymétrie des effets des facteurs de trans-régulation qui semble être à l’origine du phénomène de «level expression dominance». Pour l’allopolyploïde, l’étude de l’expression relative des gènes homéologues à l’échelle du génome a révélé que les gènes homéologues des deux sous-génomes s’inter-régulent et contribuent au transcriptome. Le transcriptome de jeunes feuilles de C. arabica cultivés à deux conditions de températures, chacune convenant à l’une des espèces parentales a été analysé pour étudier la variation de l’expression des gènes homéologues chez C. arabica et son implication dans les capacités adaptatives. La contribution des sous-génomes au transcriptome est faiblement modifiée par les conditions de culture et n’apparait pas directement impliquée dans la capacité de C. arabica à tolérer des amplitudes thermiques plus élevées que les espèces parentales. Ces études ont permis de caractériser la réponse transcriptionnelle à un évènement d’hybridation récent et ancien. Elles mettent en évidence les bases génétiques de la variation de l’expression allélique suite à la fusion des réseaux divergents de régulation des gènes d’espèces parentales. Elles ont permis de proposer un modèle de la régulation de l’expression des gènes homéologues pour C. arabica.Mots clés : allopolyploïdie, hybridation, homéologue, expression allélique spécifique (ASE), cis- trans-régulation, transcriptome, RNA-seq, adaptation, caféier. / Polyploidy is a prominent mode of speciation and a recurrent process during plant evolution. Allopolyploidization, that involves inter-species hybridization and genome doubling, can induce an extensive array of genomic rearrangements and gene expression changes generating plants with new abilities to adaptation. The study of the merger of divergent gene expression regulatory networks seems fundamental to elucidate the role of conciliation processes in the gene expression variations.The genus Coffea that contains diploid species able to hybridize and C. arabica a recent allopolyploid between two low divergent diploid species C. eugenioides and C. canephora, represents an appropriate model for this study. Indeed C. arabica can be grown in regions with marked variations in thermal amplitude while the parental species are less adapted to temperature variations. The aims of the present work are, on one hand, the study of the effects of hybridization on the expression and regulation of genes and on the other hand, the analysis of homeologous gene expression variation in response to changing environment.To examine the immediate effects of hybridization, the expression and regulation of genes in F1 hybrids between C. canephora and C. eugenioides were analyzed by genome-wide RNA-seq technology. Parental species are distinguished by an important proportion of trans-regulatory divergences. In hybrids, among divergently expressed genes between parental species and hybrids, 77% are expressed like one parent (expression level dominance). Gene expression was shown to result from the expression of both alleles, with occasional bias toward one genome. The gene expression patterns appear determined by complex combinations of cis- and trans-regulatory divergences of parental species and by intertwined parental trans-regulatory factors. The gene expression level depends on the simultaneous up and down-regulation of both alleles and the observed biased expression level dominance seems to be derived from the asymmetric effects of trans-regulatory parental factors on regulation of alleles. In the allopolyploid, at the genomic scale, both homeologous genes are also inter-regulated and contribute to the transcriptome.The transcriptome of leaves from C. arabica cultivated at different growing temperatures suitable for one or the other parental species was examined to analyze the variation of homeologous gene expression in variable conditions. The relative subgenome contributions to the transcriptome appear to be only marginally altered by the growing conditions. C. arabica’s ability to tolerate a broader range of growing temperatures than its diploid parents does not result from differential use of homeologs. The transcriptional response after a recent or old hybridization event was characterized by these studies. The genetic bases of the variations in allelic expression after the merger of parental gene expression regulatory networks, were elucidated and a model of regulation of homeologous gene expression in C. arabica is proposed. Keywords : allopolyploidy, hybridization, homeolog, Allelic Specific Expression (ASE), cis- trans-regulation, transcriptome, RNA-seq, adaptation, coffee tree.

Arsenic (As) undergoes extensive metabolism in biological systems involving numerous metabolites with varying toxicities. It is important to obtain reliable information on arsenic speciation for understanding toxicity and relevant modes of action. Currently, popular arsenic speciation techniques, such as chromatographic/electrophoretic separation following extraction of biological samples, may induce the alternation of arsenic species during sample preparation. The present study was aimed to develop novel arsenic speciation methods for biological matrices using surface-enhanced Raman spectroscopy (SERS), which, as a rapid and non-destructive photon scattering technique. The use of silver nanoparticles with different surface coating molecules as SERS substrates permits the measurement of four common arsenicals, including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV). This speciation was successfully carried out using positively charged nanoparticles, and simultaneous detection of arsenicals was achieved. Secondly, arsenic speciation using coffee ring effect-based separation and SERS detection was explored on a silver nanofilm (AgNF), which was prepared by close packing of silver nanoparticles (AgNPs) on a glass substrate surface. Although arsenic separation using the conventional coffee ring effect is difficult because of the limited migration distance, a halo coffee ring was successfully developed through addition of surfactants, and was shown to be capable of arsenicals separation. The surfactants introduced in the sample solution reduce the surface tension of the droplet and generate strong capillary action. Consequently, solvent in the droplet migrated into the peripheral regions and the solvated arsenicals to migrated varying distances due to their differential affinity to AgNF, resulting in a separation of arsenicals in the peripheral region of the coffee ring. Finaly, a method combining experimental Raman spectra measurements and theoretical Raman spectra simulations was developed and employed to obtain Raman spectra of important and emerging arsenic metabolites. These arsenicals include monomethylarsonous acid (MMAIII), dimethylarsinous acid (DMAIII), dimethylmonothioarinic acid (DMMTAV), dimethyldithioarsinic acid (DMDTAV), S-(Dimethylarsenic) cysteine (DMAIIICys) and dimethylarsinous glutathione (DMAIIIGS). The fingerprint vibrational frequencies obtained here for various arsenicals, some of which have not reported previously, provide valuable information for future SERS detection of arsenicals.

Master of Science / Food Science Institute / Edgar Chambers, IV / A total of more than 100 different coffee samples from 14 countries around the world were used to create a coffee lexicon. The first list of terms consisted of 74 attributes that were developed from the review of 13 samples from Colombia. A second development incorporated an existing commercial lexicon and examined an additional of 72 coffee samples from different parts of the world. Validation sessions were also performed with 20 samples from the area of San Adolfo, Colombia. Principal Component Analysis (PCA) was used to mapped the scores obtained during the validation phase of the terminology, the panelists were able to described specific characteristics that were present in the coffee samples such as sweet, nutty and fruity notes, as well as the differentiation of notes such as burnt, smoky, astringent, acrid and bitter. At the end of the process, a total of 110 attributes and their references were identified. Another study was conducted to identify the sensory properties of three coffee samples using four different brewing methods. The coffee samples were prepared using a consumer drip coffee maker, a home or food service automated espresso machine, a coffee grader “cupping” method and a filtered infusion method. The cupping method produced a higher intensity for the “roasted” flavor attribute across all samples. This method also tended to produce higher scores for burnt and acrid than other brewing methods. Flavor and aroma attributes both varied with preparation methods, but not necessarily in the same ways. The drip brewing method showed the most differences in the three coffee samples for aroma, flavor and aftertaste attributes, but other methods may be appropriate depending on the objectives of each study.

Made available in DSpace on 2014-06-11T19:27:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-28Bitstream added on 2014-06-13T20:16:38Z : No. of bitstreams: 1 bruno_m_me_jabo_prot.pdf: 2616643 bytes, checksum: 97247720aae07e408b197a60a6613f6a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho avaliou-se o desempenho de reatores anaeróbios de fluxo ascendente com manta de lodo (UASB), em dois estágios, em escala de bancada (volumes de 20 L e 10 L, respectivamente), alimentados com água residuária do beneficiamento de café por via úmida, submetidos à quatro cargas orgânicas volumétricas (COV) de 5,76; 3,62; 3,86 e 2,16 kg DQO total (m3 d)-1 no primeiro reator, R1. As concentrações médias de DQO do afluente variaram de 8626 a 23041 mg L-1, e dos efluentes dos reatores 1 e 2, 1095 a 11506 mg L-1 e de 424 a 9030 mg L-1, respectivamente. As eficiências médias de remoção de DQO total e SST variaram de 66 a 98% e de 93 a 97% respectivamente, no sistema com reatores (UASB) em dois estágios. O teor de metano no biogás variou de 69 a 89% para o reator 1 e de 52 a 73% no reator 2. A produção volumétrica máxima de metano, 0,563 m3 CH4 (m3 reator d)-1 foi obtida com COV de 3,86 kg DQO (m3 d)-1 e TDH de 124 h. Os valores médios de pH variaram na faixa de 4,7 a 7,7 e 4,9 a 8,0 nos efluentes dos reatores 1 e 2, respectivamente. A concentração de ácidos voláteis totais manteve-se estável à níveis inferiores a 200 mg L-1 nos ensaios 2, 3 e 4. As concentrações médias de fenóis totais do afluente variaram de 79,7 a 97,4 mg L-1, e as eficiências médias de remoção no conjunto de reatores UASB em dois estágios variaram de 72 a 90%. / In this work it was evaluated the performance of two stage upflow anaerobic sludge blanquet (UASB), in lab scale, treating a liquid effluent from the coffee pulping, submitted to organic load rate of 5,76; 3,62; 3,86 and 2,16 kg COD (m3 d)-1 in the first reactor. The medium values of total COD affluent varied from 15439 to 23041 mg L-1, and in the effluent from the reactors 1and 2, 1095 to 11506 mg L-1, and 424 to 9030 mg L-1, respectively. The medium values of removal efficiences of total COD and TSS varied from 66 to 98% and 93 to 97%, respectively, in the system of treating with reactors UASB, in two stages. The content of methane varied from 69 to 89% in reactor 1 and 52 to 73% in reactor 2 . The maximum volumetric methane production 0,563 m3 CH4 (m3 reactor d)-1 was obtained with OLR of 3,86 kg COD (m3 d)-1 and HDT of 124 hours. Average pH values ranged from 4,7 to 7,7 and 4,9 to 8,0 for effluents of first and second reactors. Total volatile acid concentration was kept below 200 mg L-1. The medium values of total phenols of affluent ranged from 79,9 to 97,4 mg L-1, and the average removal efficiency ranged from 72 to 90% in the two stages upflow anaerobic sludge blanket (UASB).

Made available in DSpace on 2014-06-11T19:23:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-06-21Bitstream added on 2014-06-13T19:50:00Z : No. of bitstreams: 1 cintra_aco_me_jabo.pdf: 322663 bytes, checksum: 6a89d275eb3f46efe98f953be36c221f (MD5) / O café é um dos principais produtos na pauta das exportações agrícolas, constituindo-se numa das mais importantes fontes de divisas para a economia brasileira. Além disso, a cafeicultura tem importante papel social no país, empregando considerável volume de mão-de-obra, devido à exigência da cultura em relação aos tratos culturais. A análise foliar é uma importante ferramenta para auxiliar no aumento de produtividade das culturas perenes em geral e, particularmente para o cafeeiro, sendo imprescindível conhecer o tamanho ideal da amostra de folhas a ser coletada, a fim de otimizar a mão-de-obra e diminuir os erros inerentes aos critérios de diagnose do estado nutricional. Neste sentido, este trabalho teve como objetivo determinar em lavouras comerciais de café com idades entre 8 e 12 anos, instaladas em Latossolo Vermelho Distrófico, submetidas a dois regimes hídricos, o tamanho de amostras foliares e a variação do erro amostral para a diagnose do estado nutricional da cultura. Foi utilizado o delineamento experimental inteiramente casualizado, composto por quatro tratamentos que constaram da amostragem de folhas em 5, 10, 20 e 40 plantas de cafeeiro e cinco repetições, no sistema de sequeiro e irrigado. Concluiu-se que para a determinação de macronutrientes, a amostragem de folhas em 10 e 20 plantas por unidade amostral nos sistemas irrigado e sequeiro respectivamente, são suficientes para manter o erro amostral menor que 10%. Para realizar as determinações químicas de macro e micronutrientes, 20 plantas são suficientes para manter o erro na estimativa da média amostral menor que 10% no sistema irrigado e sequeiro, exceto para o Cu e Mn que necessitam de amostragem superior a 40 plantas no sistema de sequeiro / Coffee is one of the main products on the list of agricultural exports, becoming one of the most important sources of foreign exchange for the Brazilian economy. Additionally, coffee has an important social role in the country, employing considerable amount of manpower due to the requirement of culture in relation to cultural practices. The leaf analysis is an important tool to help increase productivity of perennial crops in general and, particularly for coffee and is essential to know the ideal size of a leaf sample to be collected in order to optimize the manpower and reduce errors inherent in the criteria for diagnosis of nutritional status. This study aimed to determine in 8-12 years-old commercial crops of coffee, installed in Oxisol submitted to two water regimes, the size of leaf samples and the variation of sampling error for the diagnosis of nutritional status of plants coffee. A completely randomized design, consisting of four treatments was used, that consisted of leaf sampling at 5, 10, 20 and 40 coffee plants and five repetitions, to with and without irrigation system. To determination of macronutrients, the sample sheets 10 and 20 plants per unit sample with and without irrigation systems respectively, was sufficient to maintain the sample error less than 10. To determine chemical analysis of macro and micronutrients, 20 plants were enough to keep the error in estimating the sample mean less than 10% in the with and without irrigation systems, except for Cu and Mn that need more than 40 plants without irrigation system

Made available in DSpace on 2014-06-11T19:24:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-21Bitstream added on 2014-06-13T20:32:11Z : No. of bitstreams: 1 huamanimelendez_vj_me_sjrp_parcial.pdf: 569064 bytes, checksum: a421744f281164e37617b166ac6f3843 (MD5) Bitstreams deleted on 2014-10-03T16:24:34Z: huamanimelendez_vj_me_sjrp_parcial.pdf,Bitstream added on 2014-10-03T16:27:33Z : No. of bitstreams: 2 huamanimelendez_vj_me_sjrp_parcial.pdf.txt: 53713 bytes, checksum: 111b3a17f7877d22607c79773592bd40 (MD5) 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-03T16:33:11Z: 000698203.pdf,Bitstream added on 2014-10-03T16:43:25Z : No. of bitstreams: 2 huamanimelendez_vj_me_sjrp_parcial.pdf.txt: 53713 bytes, checksum: 111b3a17f7877d22607c79773592bd40 (MD5) 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-03T16:48:51Z: 000698203.pdf,Bitstream added on 2014-10-03T16:49:44Z : No. of bitstreams: 1 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-27T11:47:01Z: 000698203.pdf,Bitstream added on 2014-10-27T11:48:02Z : No. of bitstreams: 1 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) / Oea / A presente pesquisa propõe como alternativa melhorar o processo de extração da cafeína dos grãos de café de variedade arábica utilizando água como solvente com auxílio de ultrassom de alta intensidade. Na primeira etapa da pesquisa foram avaliadas propriedades físicas do grão no processo de hidratação e a proposição da solução analítica para a semiesfera da equação de Fick. Na segunda etapa foi avaliado o coeficiente de difusão da cafeína no processo de extração com água em diferentes temperaturas (30, 40, 50 e 60 °C). Na terceira etapa foi empregado um delineamento composto central rotacional para avaliar a porcentagem de recuperação e o coeficiente de difusão de cafeína nos grãos de café, para os tempos de 15, 30 e 60 minutos sob a influência do ultrassom de alta intensidade (30, 45, 65, 85 e 100% da amplitude da potência) em diferentes ciclos de aplicação (30, 45, 65, 85 e 100%) e em função da temperatura de extração (30, 36, 45, 53 e 60 °C). O modelo matemático para geometria semiesférica apresentou melhor ajuste aos dados experimentais, tanto para a difusão de água nos grãos de café no processo de hidratação, como para o processo de extração de cafeína em meio aquoso. O coeficiente de difusão de água no grão de café no processo de hidratação variou de 6,901 .10-11 m2 s-1 a 30 °C até 3,119 .10-10 m2 s-1 a 60 °C, com energia de ativação de 41,243 kJ mol-1. Para a difusão da cafeína, o modelo matemático para semiesfera também resultou ser ligeiramente superior na maioria dos casos, onde o coeficiente de difusão variou de 1,026 .10-11 m2 s-1 a 30 °C até 9,004 .10-11 m2 s-1 a 60 °C com uma energia de ativação de 59,933 kJ mol-1. Na aplicação de ultrassom de alta intensidade, os fatores de potência de ultrassom e a temperatura... / This research proposes as an alternative to improve the process of extracting caffeine from coffee beans, arabica variety, using water as solvent, assisted by high-intensity ultrasound. In the first stage of the research, physical properties of the grain were evaluated in the hydration process and the proposition of an analytical solution for the semi-sphere of the Fick equation. In the second stage, it was determined the diffusion coefficient of caffeine in the extraction process with water at different temperatures (30, 40, 50 and 60 °C). In the third stage, a central composite rotational design was used to assess the percentage of recovery and the diffusion coefficient of caffeine in coffee beans, for caffeine extraction upon different treatment times (15, 30 and 60 minutes) under the influence of high-intensity ultrasound (30, 45, 65, 85 and 100% of the power amplitude), different application cycles (30, 45, 65, 85 and 100%), as a function of the temperature (30, 36, 45, 53 and 60 °C). The mathematical model presented by the semispherical geometry showed the best fit to the experimental data, in comparison to Fick's sphere geometry approach, both for the diffusion of water in the coffee beans in the hydration process, and for the extraction process of caffeine in aqueous media. The diffusion coefficient of water in the coffee bean in the hydration process ranged from 6.901 ×10-11 m2 s-1 at 30°C to 3.119 ×10-10 m2 s-1 at 60°C, with and activation energy of 41.243 kJ mol-1. For the diffusion of caffeine in the grain, the semi-sphere mathematical model also resulted slightly better fitting in most cases, with a diffusion coefficient ranged from 1.026 ×10-11 m2 s-1 at 30°C to 9.004 10-11 m2 s-1 at 60°C, and an activation energy of 59.933 kJ mol-1. In the high-intensity ultrasound assisted extraction process, the ultrasound... (Complete abstract click electronic access below)