Thesis (MSc (Plant Biotechnology))--University of Stellenbosch, 2006. / Fructose 2,6-bisphosphate (Fru 2,6-P2) is an important regulatory molecule in plant carbohydrate metabolism. There were three main objectives in this study. Firstly, to determine whether the recombinant rat 6-phosphofructo 2-kinase (6PF2K, EC 2.7.1.105) and fructose 2,6-bisphosphatase (FBPase2, EC 3.1.3.11) enzymes, which catalyse the synthesis and degradation of Fru 2,6-P2 respectively, showed any catalytic activity as fusion proteins. Secondly, to alter the levels of Fru 2,6-P2 in sugarcane, an important agricultural crop due to its ability to store large quantities of sucrose, by expressing the recombinant genes. Thirdly, to investigate whether sugar metabolism in photosynthetic- (leaves) and non-photosynthetic tissue (internodes) were subsequently influenced. Activity tests performed on the bacterially expressed glutathione-S-transferase (GST) fusion 6PF2K and FBPase2 enzymes showed that they were catalytically active. In addition antibodies were raised against the bacterially expressed proteins. Methods for extracting and measuring Fru 2,6-P2 from sugarcane tissues had to be optimised because it is known that the extraction efficiencies of Fru 2,6-P2 could vary significantly between different plant species and also within tissues from the same species. A chloroform/methanol extraction method was established that provided Fru 2,6-P2 recoveries of 93% and 85% from sugarcane leaves and internodes respectively. Diurnal changes in the levels of Fru 2,6-P2, sucrose and starch were measured and the results suggested a role for Fru 2,6-P2 in photosynthetic sucrose metabolism and in the partitioning of carbon between sucrose and starch in sugarcane leaves. Transgenic sugarcane plants expressing either a recombinant rat FBPase2 (ODe lines) or 6PF2K (OCe lines) were generated. The ODe lines contained decreased leaf Fru 2,6-P2 levels but increased internodal Fru 2,6-P2 levels compared to the control plants. Higher leaf sucrose and reducing sugars (glucose and fructose) were measured in the transgenic plants than the control plants. The transgenic lines contained decreased internodal sucrose and increased reducing sugars compared to the control plants. Opposite trends were observed for Fru 2,6-P2 and sucrose when leaves, internodes 3+4 or internodes 7+8 of the different plant lines were compared. In contrast, no consistent trends between Fru 2,6-P2 and sucrose were evident in the OCe transgenic lines.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The deterioration of harvested sugarcane as a result of bacterial growth causes major losses of sucrose and a build-up of exopolysaccharides (EPS). Polysaccharides present during production increase the massecuite viscosity, which negatively influences evaporation and crystallisation. In this study 38 culturable EPSproducing bacteria were isolated from milled sugarcane. Analysis of the EPS showed the ubiquitous presence of glucose, however, 14 polysaccharides also contained mannose, fructose or galactose. In vitro treatment using Chaetomium erraticum dextranase to evaluate is effectiveness indicated that 37 of the EPS were hydrolysed to some extent. There were 21 polysaccharides that were only partially digested. The capacity of the isolates to produce EPS on different sugars indicated a correlation between sucrose and polysaccharide formation in 37 isolates. The results indicate there are more species involved in EPS production than previously thought as well as the presence of non-dextran polysaccharides. / AFRIKAANSE OPSOMMING: Bakteriële groei veroorsaak ‘n afname in gehalte, sukrose en ‘n verhoging in die hoeveelheid van eksternepolisakkeriede (EPS). Die verhoogde konsentrasie van polysakkariede gedurende die verwerkingsprosses veroorsaak ‘n verhoging in “massecuite” viskositeit. Hierdie verskynsel het ‘n nadelige uitwerking op die verdamping en kristalvorming van die produk. In gemaalde skuikerriet was 38 groeibare EPS-produserende bakterieë geisoleer. Die geanaliseerde EPS van hierdie bogenoemde bakterieë was daar in almal glukose teenwoordig. In 14 van hulle was mannose, fruktose en galaktose ook gevind. Die in vitro effektiwieteit van Chaetomium erraticum dekstranase op die EPS het gewys dat 37 het tot ‘n mate gehidroliseer maar 21 was net gedeeltelik verteer. As gevolg van die bo-genoemde resultate was daar gevind dat sukrose was ‘n noodsaaklike subtraat vir EPS produksie in die geisoleerde bakterieë. In hierdie studie was bevestig ‘n groter verskiedenheid EPS-produserende bakterieë gevind was en dat hulle assosiasie aan sukierriet prossering meer kompleks is as wat vooreen gedink was.

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: In the rainfed areas of the South African sugar industry the unpredictability of rainfall is of major concern for producers. Currently, research into the drought tolerance of South African sugarcane varieties is very limited. Knowledge of varietal drought tolerance potential would allow for more informed decision making when it comes to planting a crop that stays in the ground for between five and fifteen years. The aim of this study was to ascertain the drought tolerance potential of commercial sugarcane varieties using historical field trial data by employing statistical modelling. The first step was to establish a reliable methodology of quantifying the level of drought stress, defined through a drought stress index (DSI), employing the sugarcane growth modelling software Canesim. The second step was to use the selected DSI to evaluate and rate the drought tolerance potential of commercial varieties. Of the six DSI’s calculated, the index comprising a ratio of Canesim simulated rainfed yield (representative of a water stressed environment) to Canesim simulated irrigated yield (representative of a water unstressed environment) was the best at quantifyingthe level of trial drought stress. Using three varieties with previously identified drought potential, two intermediate susceptible (IS) and one intermediate (I) variety, this was the only DSI that was able to quantify all the differences between the varieties. Using the selected DSI, two different methodologies were used to evaluate varietal drought tolerance potential: General linear regression and Residual maximum likelihood meta-analysis. The regression method proved to be a better method of varietal rating when using historical field data. The two rainfed regions, coastal and midlands were analyzed separately due to the difference in climatic conditions. Using the regression analysis, with N12 as the observed intermediate reference variety, coastal varieties were rated as being susceptible (N16, N19, N39 and NCO376) or intermediate (N27, N29, N33, N36, N41, N45, N47). Rating of the midlands varieties, with both statistical methods, were unsuccessful. / AFRIKAANSE OPSOMMING: Binne die droëland produksiegebied van die Suid-Afrikaanse suikerindustrie is die wisselvalligheid van reënval ʼn groot bron van kommer vir produsente. Navorsingsresultate aangaande die droogtetoleransie van Suid-Afrikaanse suikerrietvariëteite is baie beperk. Aangesien suikerriet aanplantings vir vyf tot vyftien jaar in produksie mag bly, is kennis aangaande droogtetoleransie noodsaaklik vir ingeligte besluite rondom variëteit keuse. Die doel van hierdie studie was om die droogtetoleransie van kommersiële variëteite met behulp van historiese veldproef resultate en statistiese modellering te bepaal. Die eerste stap was die ontwikkeling van betroubare metodiek wat die graad van droogtestremming kwantifiseer deur middel van droogtestremmingsindekse (DSI’s) wat met die suikerriet produksiemodel, Canesim, bereken is. Die tweede stap was om die DSI’s te gebruik om geselekteerde kommersiële variëteite vir droogtetoleransie te evalueer en volgens toleransie te rangskik. Van die ses DSI’s wat geëvalueer is, was die indeks wat die verhouding tussen Canesim gesimuleerde droëland opbrengs (verteenwoordigend van ʼn omgewing met droogte) en Canesim gesimuleerde besproeide opbrengs (verteenwoordigend van ʼn omgewing sonder droogte) omskryf het, die mees effektiefste om die graad van droogtestremming te kwantifiseer. Hierdie DSI was vervolgens die enigste wat verskille in droogtetoleransie tussen drie variëteite van bekende droogte toleransie kon kwantifiseer. Deur gebruik van hierdie DSI is twee verskillende metodes aangewend om die droogtetoleransie van variëteite te evalueer naamlik: Algemene Lineêre Regressie en Residuele Maksimum Aanneemlikheid. Die regressiemetode was die mees effektiefste om variëteite volgens droogtetoleransie, op grond van historiese veldproef resultate, te rangskik. Die twee droëland produksiegebiede, naamlik die kusstrook en Natalse Middellande is afsonderlik geanaliseer as gevolg van klimaatsverskille. Met behulp van die regressiemetode is die kus-variëteite as droogtesensitief of -intermediêr geklassifiseer, met N27, N29, N33, N36, N41, N45 en N47 as droogte-intermediêr en N16, N19, N39 en NCO376 as droogtesensitief. Soortgelyke klassifisering van die variëteite wat in die Natalse Middellande verbou word was nie met enige van die statistiese metodes suksesvol gewees nie.

Orientador: Fernando Broetto / Banca: José Pedro Serra Valente / Banca: Luciana Francisco Fleuri / Resumo: O bioetanol é um combustível produzido por meio da fermentação do açúcar do caldo da cana, que representa apenas um terço do carbono (energia), presente na planta. Atualmente, estão sendo feitos esforços para o aproveitamento do restante da biomassa, divididos entre as folhas e bagaço do colmo. Esta biomassa lignocelulósica poderia ser aproveitada para produção de etanol, desde que submetida a processos hidrolíticos químicos (ácidos e bases) e enzimáticos gerando açúcares fermentescíveis. Pela fermentação alcoólica é possível a produção de etanol a partir da mistura de açúcares liberados. Neste trabalho procurou-se a padronização de procedimentos para avaliar o pré-tratamento físico e químico do bagaço da cana-de-açúcar, aliado a diferentes tratamentos térmicos a partir de duas granulometrias de bagaço (1,1 e 2,5 mm). Para o delineamento experimental, utilizou-se tratamentos ajustados em fatorial 4 X 5, sendo que as variáveis foram a influência do tempo de pré-tratamento (0, 15, 30, 45 e 60 minutos) e concentração de ácido sulfúrico (H2SO4) a 7 e 9%. Estes fatores exerceram influência sobre o desempenho da pré-hidrólise, medido pela liberação açúcares redutores (AR) na solução e a % de espécies químicas no bagaço prétratado / Abstract: Bioethanol fuel is produced through the fermentation of sugar cane juice, which representes only a third of the carbon (energy) present in the plant. Currently, efforts are being made to the use of the remaining biomass, divided among the leaves and seed stalk. This lignocellulosic biomass could be used for ethanol production, provided that undergo hydrolytic process chemicals (acids and bases) and enzymatic generating fermentable sugars. For fermentation is possible to produce ethanol from mixed sugars released. This research is the standardization of procedures to assess the pre-treatment physical and chemical properties of bagasse from sugar cane, coupled with different thermal treatments from two particle sizes of mulch (1,1 and 2,5 mm). For this experiment, we used adjusted treatments in a factorial 4 x 5, and the variables were the influence of time of pretreatment (0, 15, 30, 45 and 60 minutes) And concentration of sulfuric acid (H2SO4) 7 and 9%. These factors have exerted influence on the performance of pre-hydrolysis, measured by the release sugars (RS) in the solution, and% of chemical species in the pretreated bagasse / Mestre

Made available in DSpace on 2014-06-11T19:23:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-01Bitstream added on 2014-06-13T19:49:39Z : No. of bitstreams: 1 silva_lm_me_botib.pdf: 309558 bytes, checksum: ca7e6d3ba3cb545638804298fc66a9c0 (MD5) / O objetivo deste trabalho é propor um modelo matemático que consiste em determinar quais variedades de cana-de-açúcar adaptável ao solo local serão plantadas nos talhões disponíveis de forma a obter o menor custo possível para o processo de colheita e transporte da cana, e ainda desenvolver e testar um algoritmo genético (AG) para investigar a solução deste problema. Inicialmente é feito um breve estudo do ciclo produtivo da cana-de-açúcar, dos prazos para a eliminação de sua queima e do custo, de sua colheita e transporte até a usina. Em seguida estuda-se o algoritmo Branch-and-Bound, o qual dentre os métodos exatos é bastante utilizado para resolver Problemas de Programação Linear Inteira (PPLI). Para testar e comparar a performance do algoritmo genético com o Branch-and-Bound foram realizadas quatro simulações com diferentes áreas de plantio e número de variedades, simulando situações reais na região geográfica trabalhada. Os resultados foram analisados e discutidos neste texto, mostrando que o algoritmo genético pode ser uma ferramenta alternativa e de grande utilidade para problemas de grande porte / The objetive of this study is to propose a mathematical model that consist of determining which varieties of sugar cane adaptable to local soil should be planted in plots available in order to obtain the lowest cost to the process of harvesting and transportation of cane, and further develop and test a genetic algorithm (GA) to investigate the solution of this problem. Initially it has been done a short study of the production cycle of sugar cane, the deadline for the elimination of his burns and the cost of harvest and transport to the mill. In the next step, we studied the algorithm Branch-and-Bound, which among methods available is often employed to solve Integer Linear Programming Problems (PPLI). To test and compare the performance of the genetic algorithm with the Branch-and-Bound simulations were performed with four di®erent planting areas and number of varieties, simulating real situations in the geographical region worked. The results were analyzed and discussed in this text, showing that the genetic algorithm can be an alternative tool and very useful for large problems

Made available in DSpace on 2016-06-02T18:57:38Z (GMT). No. of bitstreams: 1 4466.pdf: 1635891 bytes, checksum: c10a551b9403d69971333d91fd253cd9 (MD5) Previous issue date: 2012-05-24 / Financiadora de Estudos e Projetos / This work aimed to evaluate the physical-chemical and acceptance of sugarcane spirit produced with juice originated from different preparations of organic sugarcane. It was used the sugarcane variety RB867515 in the following treatments: A = crush of sugarcane with straw and bark, B = crush of sugarcane without straw and with bark, C = crush of sugarcane without straw and bark, and D = crush of sugarcane internodes without straw and bark. The distillate of sugarcane spirit was produced at the Laboratory of Organic Agriculture and Foods in the Center for Agricultural Science (CCA)/Federal University of São Carlos (UFSCar) situated at Araras, São Paulo State, Brazil. The fermentation of juice was developed in four fermentation vessels of stainless steel plates with 1000L capacity (each one fermentation vessels received the juice from treatments) using industrial yeast (8g / L) for each one. Were measured the following physical-chemical properties: total acidity, esters, aldehydes, higher alcohols, methanol, cupper and pH. The distillate were evaluated for color, aroma, flavor, body and overall impression, using sevenpoint hedonic scale ranging from "really liked" to "dislike very much." Data were analyzed using analysis of variance and Tukey's test to verify differences between the means (p ≤ 0.05). The results of acceptance tests and physicalchemical analysis showed that the sugarcane spirit with better acceptance among consumers was that one produced from sugarcane without straw and with bark, and the sugarcane spirit with the lowest acceptance was that one produced from the juice extracted from the internodes. / O objetivo deste trabalho foi avaliar as características físico-químicas e aceitabilidade de cachaças produzidas com caldo originado de diferentes preparos da cana-de-açúcar orgânica. Utilizou-se a variedade RB867515 nos seguintes tratamentos: A = moagem da cana-de-açúcar com palhas e cascas; B = moagem da cana-de-açúcar sem palhas e com cascas; C = moagem da cana-de-açúcar sem palhas e sem cascas; e D = moagem dos internódios da cana-de-açúcar sem palha e sem casca. A produção das cachaças foi realizada no Laboratório de Agricultura Orgânica e Alimentos Orgânicos, no CCA/UFSCar Araras, Estado de São Paulo, Brasil. As fermentações foram desenvolvidas em quatro dornas de capacidade de 1000 litros em aço inox (cada dorna recebeu um método de preparo da matéria-prima) utilizando-se o fermento prensado (fermento industrial, 8g/L) para todos os tratamentos. Foram realizadas as seguintes análises físico-químicas: acidez total, ésteres, aldeídos, alcoóis superiores, metanol, cobre e pH. Ainda, procedeu-se à avaliação de aceitação das cachaças em relação à cor, aroma, sabor, corpo e impressão global, utilizando-se escala hedônica de sete pontos variando de gostei muito a desgostei muito . Os dados foram submetidos à análise de variância e teste de Tukey para verificar diferenças entre as médias (p≤0,05). Os resultados dos testes de aceitação e das análises físico-químicas mostraram que a cachaça de melhor aceitação entre os consumidores foi aquela produzida com o caldo originado da moagem da cana sem palha e com casca, e a de menor aceitação foi a cachaça produzida com o caldo extraído pela moagem dos internódios sem palha e sem casca.

Orientador: Luis Augusto Barbosa Cortez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-10T04:47:38Z (GMT). No. of bitstreams: 1 CastanedaAyarza_JuanArturo_M.pdf: 2088769 bytes, checksum: c1479b9871597f5da7758c6617681d7c (MD5) Previous issue date: 2007 / Resumo: o objetivo principal desta dissertação é mostrar o potencial dos méis da cana-de-açúcar na produção do etanol combustível nos principais países industrializadores da cana, visando aumentar, no curto prazo, a oferta mundial do etanol anidro para ser misturado à gasolina. A partir do cálculo do potencial dos méis da cana foi analisado o impacto que teria o aumento de produção do etanol no mercado interno e externo do açúcar nos países pesquisados, assim como as perspectivas do incipiente mercado internacional do etanol combustível, através da projeção da demanda de gasolina e da análise dos programas que apóiam o uso e a produção dos biocombustíveis. Assim, através da projeção da demanda potencial por etanol dos países consumidores, estimar que vários dos paises industrializadores da cana estudados teriam possibilidades de produzir em média 1 bilhão de litros de etanol anidro por ano no curto prazo, e que o comércio internacional de etanol, embora atualmente esteja sustentado pelos acordos de comércio internacional e por acordos bilaterais, tem possibilidades de aumentar seus fluxos à mercê do rápido crescimento da demanda mundial. Finalmente, concluímos que a cana-de-açúcar e a sua indústria têm possibilidades de impulsionar no curto prazo e até sustentar o desenvolvimento de um novo mercado internacional de etanol combustível / Abstract: The main objective of this dissertation is to show the potential of the molasses from sugarcane, for the ethanol fuel production in the main producer countries of the sugarcane, aiming at the increment, in the short term, worldwide supply of anhydrous ethanol to be mixed with the gasoline. From the calculation of the molasses potential from sugar cane, have been analyzed the impact that would have the increase of ethanol production in the internal and external sugar market in the searched countries, as well as of the new international ethanol fuel market, through the projection of the demand of gasoline and the analysis of the programs that support the use and the production of the biofuels. Thus, it was possible to project the demand of ethanol in the potential consuming countries, to consider that several of the producer countries of the sugarcane would have possibilities of producing in average 1 billion of liters of anhydrous ethanol per year in the short term, and that the international trade of ethanol, although at the moment is sustained by the agreements of international trade and for bilateral agreements, it has possibilities of increasing his flows at the mercy of the fast growth of the worldwide demand. Finally, it is the concluded that the sugar cane and its industry have possibilities to stimulate in short term and until sustaining the development of a new international market of ethanol fuel / Mestrado / Analise da Demanda e do Suprimento de Energia / Mestre em Planejamento de Sistemas Energéticos

O presente trabalho foi desenvolvido a partir de um experimento de campo, conduzido no período de setembro de 2000 a maio de 2001, na região canavieira de Piracicaba (SP), com a terceira soca da variedade SP 80-1842, cultivada em ARGISSOLO VERMELHO-AMARELO distrófico arenoso e colhida sem queima e mecanicamente. O objetivo deste estudo foi avaliar a eficiência agronômica de diferentes fontes nitrogenadas em sistema de colheita de cana crua por meio de: a) medidas das perdas de nitrogênio por volatilização da amônia; b) avaliação do estado nutricional das plantas; c) avaliação de atributos químicos do solo; d) avaliação da produção de colmos e de açúcar; e) ava liação de atributos tecnológicos do caldo. A dose de nitrogênio foi 100 kg ha -1 de N em todos tratamentos, que também receberam 150 kg ha -1 de K2O aplicados como KCl. Utilizou-se o delineamento experimental em blocos completos casualizados, com sete níveis de fator em cinco repetições. Os fatores foram: T0 - testemunha, T1 - uréia, T2 - uran, T3- uréia + sulfato de amônio, T4 - Ajifer, T5 - uréia + gesso aplicados na superfície e T6 - Uréia incorporada. Perdas por volatilização de amônia foram avaliadas em T0, T1, T2, T3 e T4 por meio de coletores semi-aberto estáticos colocados em cada uma das parcelas em que estudou-se a volatilização. Foram colocadas seis bases distintas para cada coletor, onde aplicou-se as fontes nitrogenadas na dose de 100 kg ha -1 de N. O N-NH3 volatilizado foi retido em espumas embebidas em solução ácida e extraído com solução de KCl para posterior quantificação das perdas. Avaliações do estado nutricional das plantas, de atributos químicos do solo, de produtividade e qualidade foram efetuadas em todos tratamentos. A avaliação do estado nutricional foi feita pela análise química dos teores de nutrientes nas folhas que foram amostradas quatro meses após brotação das soqueiras. Atributos químicos do solo foram avaliados por meio de análises laboratoriais de amostras coletadas nas camadas de 0 a 5 e 5 a 10 cm de profundidade, aos três e cinco meses após aplicação dos tratamentos. A produção de colmos por hectare foi avaliada por ocasião da colheita, da mesma forma que atributos tecnológicos do caldo. Analisou-se teores de nutrientes na palha que foi amostrada aleatoriamente fora das parcelas em que aplicou-se a adubação nitrogenada. Os resultados mostraram que os tratamentos T1 e T3 apresentaram perdas por volatilização de aproximadamente 35% do N aplicado e que os tratamentos T2 e T4 apresentaram perdas de aproximadamente 15% e 9% do N aplicado, respectivamente. Teores foliares de N foram inversamente proporcionais às perdas por volatilização. A adubação nitrogenada e presença de palha aumentaram o teor de matéria orgânica nos 10 primeiros centímetros de solo. Sem a influência da adubação nitrogenada, ocorreu redução de 50% na massa seca da palhada. Não houve liberação de N e S mas a redução nas relações C/N e C/S indicou possibilidade de mineralização de nitrogênio e enxofre do resíduo vegetal. As soqueiras responderam em produtividade à adubação nitrogenada e às perdas ocorridas por volatilização de N-NH3. / The present work was advanced by a field experiment that was conducted from September 2000 to May 2001 in Piracicaba cane region with the variety SP 80-1842 in the third sugarcane cut, tilled in Arenic Kanhaplodults and with mechanical harvest without burning. The aim of this study was to evaluate the agronomic efficiency from nitrogen sources in sugarcane harvest system without burning. The efficiency was evaluated through: a) measure of N-NH3 losses, b) plant nutritional condition evaluations, c) soil chemical attribute evaluations, d) stem and sugar productions, e) sugarcane juice technological attribute evaluations. The nitrogen dose was standardized in 100 kg ha -1 in every treatment and in the same way to potassium fertilizer which dose was standardized in 150 kg ha -1 of K2O supplied by KCl. The experimental design was in complete randomized blocks with seven factor levels in five replications. The factors were: T0 – Control, T1 – Urea, T2 – Uan, T3 – Urea + ammonia sulfate, T4 – Ajifer, T5 – Urea + gypsum, T6 – Incorporated urea. Losses by ammonia volatilization were evaluated in the treatments T0, T1, T2, T3 and T4 by static semi-open NH3 collectors that were set in each experimental plot where N-NH3 losses were measured. Six different bases were set to each collector, which were applied dose to fit 100 kg ha –1 of nitrogen by different sources. The N-NH3 was collected by foam absorbers soaked in acid solution after that was extracted by KCl solution to be quantified later. Plant nutritional conditions, soil chemical attributes, productivity and quality were evaluated in every treatment. The plant nutritional conditions were evaluated by leaf chemical analysis and the leaves were sampled four months after the sugarcane sprout. Soil chemical attributes were evaluated by samples laboratories analyses and the samples were collected in 0-5 and 5-10 cm of depth four and six months after treatments application. The stem and sugar productivity and juice technological attributes were measured after the harvest. The straw was randomized sampled outside experimental plots and its nutrients content was determinate. The results showed that N-NH3 losses were nearly 35% of the nitroge n applied to T1 and T3 and losses in T2 and T4 were low, nearly 15% and 9%. The leaf diagnosis showed that leaves nitrogen content in treatments with low nitrogen losses was bigger than treatments where nitrogen losses were high. Nitrogen sources applied over the straw resulted in organic matter increase at the soil surface. It didn't happen straw nitrogen and sulfur liberation but the decrease in C/N and C/S relation indicated the possibility to happen nitrogen and sulfur liberation from the vegetal residue. The stalks of sugarcane answered in productivity to nitrogen fertilizer and to nitrogen losses.

A qualidade da fibra é um dos fatores mais importantes que regulam o consumo de matéria seca dos ruminantes. A ensilagem altera a qualidade nutricional da forragem conservada. Contudo, o objetivo deste estudo foi avaliar o consumo, cinética e ecossistema ruminal de tourinhos alimentados com dietas contendo cana-de-açúcar (Saccharum officinarum L.) fresca ou ensilada, com alta ou baixa digestibilidade da fibra, sobre os seguintes parâmetros: 1) consumo de matéria seca; 2) taxa de digestão e passagem ruminal da FDN; 3) parâmetros de fermentação ruminal e 4) quantificação de bactérias ruminais celulolíticas e amilolíticas. Foram utilizados oito novilhos da raça Nelore, fistulados no rúmen, com peso vivo de 275 ± 22 kg e 18 meses de idade. As rações experimentais foram compostas de 60% de concentrado na matéria seca. O delineamento experimental foi de dois quadrados latinos 4x4 contemporâneos. A massa total do conteúdo ruminal e volume foram determinados por esvaziamento total do rúmen. O genótipo de alta DFDN aumentou o consumo de MS, somente na forma de silagem. O processo de ensilagem não alterou o efeito da alta DFDN sobre o CMS. Os tratamentos com cana fresca não tiveram diferença no CMS, quanto ao genótipo da cana. O aumento da DFDN ou o modo de conservação da cana não afetaram a digesta total do rúmen, a quantidade de MS e o teor FDNi no compartimento ruminal. Já a quantidade de FDN na digesta ruminal aumentou com a redução da qualidade da fibra. A maior digestibilidade da fibra e a conservação na forma de silagem aumentaram a taxa de renovação e a taxa de passagem da FDN. A taxa de digestão foi maior para os tratamentos com silagem de cana. A alimentação com cana fresca aumentou o total de AGCC e a concentração molar de propionato. Já os tratamentos com silagem obtiveram pH mais elevado e maior concentração molar de ácido acético. A menor digestibilidade da fibra aumentou a concentração da amônia ruminal. A alimentação com cana fresca aumentou a população das bactérias amilolíticas da espécie Streptococcus bovis, assim com as bactérias fibrolíticas das espécies Ruminococcus albuns e Fibrobacter succinogenes. A maior digestibilidade da fibra aumenta a taxa de passagem e consequentemente, o consumo de matéria seca de novilhos alimentados com silagem de cana-de-açúcar. O processo de ensilagem não interfere no efeito da maior DFDN sobre o CMS. / The quality of fiber is one of the most important factors that regulate dry matter intake of ruminants. The ensiling process affects the nutritional quality of the conserved forage. Therefore, the aim of this study was to evaluate the intake, kinetics and ruminal ecosystem in young steers fed either fresh or ensiled sugarcane (Saccharum officinarum L.), with either high or low fiber digestibility, on the following parameters: 1) dry matter intake, 2) ruminal NDF digestion and passage rate, 3) ruminal fermentation parameters, and 4) quantification of amylolytic and cellulolytic rumen bacteria. Eight ruminally cannulated Nelore steers (275 ± 22 kg), approximately 18 months old, were used. The experimental diets contained 60% of concentrate on a dry matter basis. The experimental design was a replicated 4 x 4 Latin square. The total digesta and ruminal volume were measured by manual evacuation of digesta. Greater fiber digestibility increased DM intake only when fed as silage, therefore the ensiling process does not alter the effect of high digestibility on DMI. When fed as fresh sugarcane, the treatments (high or low NDFD) had no effect on DMI. High NDFD, or method of conservation, had no effect on rumen digesta, amounts of DM or indigestible NDF (INDF), in the rumen. Low digestibility increased the amount of NDF in the rumen. High NDFD and sugarcane preserved as silage increased ruminal NDF turnover and passage rate. Ensiling sugarcane increased the NDF digestion rate. Fresh sugarcane increased the total of SCFA and molar concentration of propionate in the rumen. Sugarcane silage treatments had a higher rumen pH and molar concentration of acetate. Low NDFD increased the concentration of ruminal ammonia. Fresh sugarcane increased the population of amylolytic and fibrolytic rumen bacteria. The higher NDFD increases the passage rate and consequently the DMI of steers fed sugarcane silage. The ensiling process does not alter the effect that high NDFD has on DMI.

Este estudo pretende contribuir para as pesquisas sobre a agroindústria canavieira no estado de São Paulo, enfocando a expansão das usinas de açúcar e de álcool entre os anos de 1930 e 1964. Trata-se de um período especialmente marcado por crise no setor cafeeiro, acelerado processo de industrialização, direcionamento da economia para o mercado interno e intervenção estatal no ramo, com a criação do Instituto do Açúcar e do Álcool (IAA), em 1933. A conjuntura de disputas e conflitos de interesses entre as regiões Nordeste e Centro-Sul do Brasil, entre fabricantes e comerciantes, e entre usineiros e fornecedores de cana-de-açúcar, culminou na consolidação de São Paulo como principal centro sucroalcooleiro do país durante as décadas de 1940 e 1950. Com o objetivo de compreender essas questões na dinâmica usineira, o presente estudo baseou-se na trajetória da Usina Monte Alegre, em Piracicaba. Localizada no mais tradicional território canavieiro de São Paulo, esta usina iniciou suas atividades como um engenho de açúcar e tornou-se um importante complexo usineiro no período enfocado, sob a administração do imigrante Pedro Morganti e empresas da família. / This study intends to contribute to the research of the sugarcane agroindustry in the state of São Paulo, focusing on the expansion of the big sugar mills between 1930-1964. It is a period particularly marked by the crisis in the coffee sector, an accelerated industrialization process, the economy orientation towards the domestic market, and state intervention with the creation of the Instituto do Açúcar e do Álcool, in 1933. The context of disputes and conflicts of interest between the Northeast and South-Central regions of Brazil, between manufacturers and traders, and between mill owners and sugarcane suppliers resulted in the consolidation of São Paulo as the main sugar and ethanol center of the country during the decades of 1940 and 1950. In order to understand these issues under the sugarcane agroindustry dynamics, this study was based on the trajectory of Usina Monte Alegre, in Piracicaba. Located in a traditional sugarcane region of São Paulo, this plant started as a sugar plantation and became an important sugarcane mill complex in the alluded period, under the administration of the Italian-born immigrant Pedro Morganti and his family businesses.