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The relation between water and sugarcane is a topic that has been greatly discussed, but on which there are few theoretical writings. To try to help with the small existing literature, this work presents a series of four studies. The first study researches the beginnings of the activity of sugarcane in Brazil and its dependence on water resources, for, without water, the plant could not live, neither the wheels of the royal mills, the first units of sugar production in the country, moved byhydraulic power, could work. The second study describes the effects of changes in the industrial production system of sugarcane by-products on the banks of the rivers where the first plants were installed, which followed the trends of the Industrial Revolution. The third study examines the technical changes that took place in the agricultural techniques of the sugarcane agribusiness as a result of the industrialization of agriculture, and its impacts on the bodies of water. The fourth study discusses the problems related to water availability and water use by the sugarcane agribusiness in São Paulo, currently the largest State producer of sugarcane and its by-products in Brazil. The objective of the work is to study the way in which water resources are being used by the sugarcane agribusiness over the years and to evaluate the quality of the relationship between water and sugarcane. The conclusion of the study indicates that water is being used carelesly by the sector, being consumed excessively in the stages of industrial processes and contaminated by effluents and agricultural waste.

Thesis (MSc)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: For the expression of transgenes in plant cells, appropriate promoter sequences have to be introduced upstream of the gene to ensure efficient transcription. While to date the maize ubiquitin (Ubi1) promoter has been the most effective transgene promoter for sugarcane, there is a high demand for tissue and stage specific promoters for localised transgene expression in the mature culm. The present study sought to characterise genes preferentially expressed in the core and peripheral tissues of the mature culm, which can further be used as research tools for specific promoter isolation. cDNA expression arrays containing 3840 clones from a late stage cDNA library representative of the core and peripheral tissues of the mature culm were prepared. The cDNA expression arrays were then differentially screened in independent hybridisation experiments with radioactively-labeled cDNA representations of core and peripheral tissues of internode 7, and peripheral tissues of internode 10. Comparison of the expression profiles of the arrayed cDNA targets in the three probes led to the identification of 60 tissue-specific, 17 stage-specific and 50 selectively expressed cDNAs within the mature sugarcane culm. ~ESTs of 33 chosen selectively expressed cDNAs with a relatively stronger pattern of expression in the core than in the peripheral tissues revealed sequence homology to a diverse collection of genes in the mature culm. These included genes associated with general cellular metabolism such as protein synthesis, protein modification and structural protein. Also identified were stress-responsive genes. The putative translational products of some of these clones had homologs that are involved in cell-wall structure in other species. These included the [acalin homolog, a lectin, hydroxyproline rich glycoprotein and structured polyprotein C. Many of the cDNAs thought to be involved in cell wall structure or stress related responses also accumulate in a developmental manner in other plants. These may indicate that specific mature culm mRNAs accumulate in response to stresses such as rapid cell expansion or as part of the late developmental program. An unexpected observation was that only one gene associated with sucrose metabolism was identified, namely sucrose synthase. These results confirmed that culm maturation was not controlled by sucrose metabolism despite its distinct physiological characteristic of storing high levels of sugars. ESTs analysis further revealed that sequence homology was not obtained for all the cDNAs exhibiting stage and tissue specific expression in the core and peripheral tissues of the mature culm. These could represent novel genes not only from sugarcane but all plants. Northern analysis demonstrated that 9 putatively identified selectively expressed genes tested so far accumulated specifically in the core and peripheral tissues of the mature culm. No expression was detected in root, leaf, leafroll and internode 3. However, their selective expression in a single internode as observed on the arrays (i.e hybridisation signal intensity being higher in the core than in the peripheral tissue) was not detected on the northern blots. These showed that cDNA expression arrays were not a highcapacity gene expression assay since they were prone to false expression analysis. The validity of results obtained through array screening should always be verified in an independent manner, preferably by the northern hybridisation analysis. Hence, the present study shows that the combination of differential screening, northern blot and DNA sequence analysis permits the rapid characterisation of differentially expressed genes in the core and peripheral tissues of the mature sugarcane culm. These can further be used as research tools for mature culm - specific promoter isolation in the sugarcane. / AFRIKAANSE OPSOMMING: Die doeltreffende uitdrukking van transgene in plantselle is afhanklik van 'n gepaste promotorvolgorde wat stroomop van die geen ingevoeg word. Die Ubi1-promotor van mielies was tot dusver die doeltreffendste transgeenpromotor in suikerriet, maar daar is 'n groot behoefte aan promotors wat weefsel- en ontwikkelingstadium-spesifieke geenuitdrukking kan beheer. Hierdie studie het op die isolering en karakterisering van gene wat selektief in die kern- of periferale stingelweefsel van suikerriet uitgedruk word, gefokus. Hierdie gene sal verder benut kan word om promotors te isoleer. eDNA uitdrukkingsreekse ("expression arrays") van 'n volwasse stingel eDNA biblioteek is voorberei. Hierdie reekse, wat 3840 klone bevat het, is in onafhanklike hibridiseringseksperimente met radioaktiefgemerkte eDNA van onderskeidelik kern- en periferale stingelweefsel van lit 7 en periferale stingelweefsel van lit 10 afgetas. 'n Vergelyking van die uitdrukkingsprofiele van die eDNA teikens in dié drie peilergroepe het tot die identifisering van 60 weefsel-spesifieke-, 17 ontwikkelingstadium-spesifiekeen 50 selektief uitgedrukte eDNAs in die volwasse suikerrietstingel gelei. Uitdrukkingsvolgordemerkers ("ESTs") van 33 geselekteerde eDNAs wat in hoër vlakke in die kern uitgedruk is, se volgordes toon homologie aan 'n wye verskeidenheid gene in die volwasse stingel. Hierdie groep sluit gene in wat met algemene sellulêre ..metabolisme soos proteïensintese, proteïenmodifisering en strukturele proteïene geassosieer is. Spanningsverwante gene is ook hier geïdentifiseer. Die transleringsprodukte van sommige klone het homoloë wat by selwandstruktuur in ander spesies betrokke is, soos die jaealin-homoloog, 'n lektien, hidroksiprolien-ryke glikoproteïen en gestruktureerde poliproteïen C. 'n Wye verskeidenheid eDNAs wat by selwandstruktuur of spanningsverwante reaksies betrokke is, akkumuleer ook in 'n ontwikkelingsafhanklike wyse in ander plante. Dit mag 'n aanduiding wees dat spesifieke mRNAs in die volwasse stingel in reaksie op spanning wat met vinnige seluitsetting gepaardgaan, versamel. Slegs een geen wat met sukrose metabolisme geassosieer is, nl. sukrosesintase, is in hierdie studie geïdentifiseer. Hierdie onverwagte waarneming het bevestig dat, ondanks suikerriet se kenmerkende vermoë om hoë konsentrasies suiker te berg, stingelveroudering nie net met sukrose metabolisme geassosieer kan word nie. Nie al die eDNA-fragmente wat geïsoleer is, het homologie aan ander gene in die internasionale databasisse getoon nie, wat moontlik kan aandui dat nuwe gene suksesvol geïsoleer is. Nege ontwikkelingstadium-spesifieke gene wat slegs in die volwasse stingelweefsels uitgedruk word, is dmv noordelike oordraganalises geïdentifiseer. Geen transkripte van hierdie gene is in die wortels, blaarrol, blare of jong stingel waargeneem nie. Die weefselspesifisiteit wat met die uitdrukkingsreekse waargeneem is, kon nie mbv noordelike orrdraganalises bevestig word nie. Dit mag 'n aanduiding wees dat die uitdrukkingsreekse vals positiewe resultate kan oplewer en dit is raadsaam om voortaan altyd die verkrygde profiele met ander, meer sensitiewe tegnieke, te bevestig. Die studie het aangetoon dat 'n kombinasie van differensiële aftasting, noordelike oordraganalise en DNA-volgordebepaling gebruik kan word om gene wat differensieel uitgedruk word in die volwasse suikerrietstingel, te identifiseer. Hierdie geenfragmente kan nou vir promotorisoleringsdoeleindes aangewend word.

Due to the increasing prevalence and severity of Al phytoxicity in certain regions of the South African sugar industry, a research programme has been initiated at SASEX to elucidate the molecular mechanisms by which sugarcane detects and responds to the metal. As part of this larger investigation, the current study aimed to assess the response of a reportedly Al tolerant cultivar, Saccharum spp. hybrid cv. N12, to phytotoxic levels of Al. Hydroponically-grown plants of this commercial genotype were used in Al inhibition studies, the results of which indicated that exposure of plants to 250µM Al for 24 hours resulted in maximum reduction of root elongation. Under these conditions, root growth was inhibited by approximately 36%, compared with only 4% for the 50µM Al treatment. Subsequently, this exposure regime was used to gather the terminal 5 to 10mm of root tips, the site of the primary Al lesion, of challenged and control, unchallenged plants for molecular analysis. Total RNA was extracted from the Al challenged and control root tips, from which mRNA was subsequently isolated, reverse transcribed and converted to double-stranded cDNA. The two populations of cDNA were reciprocally subtracted from each other and used to construct subtractive cDNA libraries in Lambda ZAP®II phages. Randomly selected clones, 576 representatives from each of the libraries, were screened using membrane-based array technology. Results indicated that only 33% (190) of the Al-treatment specific library cDNAs were found to be more highly expressed under conditions of Al stress than under control conditions. Of these potentially Al response-related cDNAs, 25 were sequenced and submitted to sequence databases for the assignment of putative identities. No genic sequences known to be directly associated with the Al stress response were identified, however, several were found to be related to pathogenesis or general stress pathways. Although further Northern hybridisation work is required to validate these results, they suggest that the induction of general stress response pathways may be involved in the aluminium stress response of this sugarcane cultivar. Such Al stress-related sequences could have applications in marker-assisted breeding programmes and as candidate genes for the genetic engineering of tolerant genotypes. / Thesis (M.Sc.)-University of Natal, Durban, 2002.

Transport logistics systems typically evolve as networks over time, which may result in system rigidity and cause changes to become expensive and time consuming. In this study a logistics model, named TranSwarm, was developed to simulate sugarcane harvesting, transport and mill-yard activities for a mill supply area. The aim was to simulate produce flow, and allow individual working entities to make decisions, driven by rules and protocols, based on their micro-environments. Noodsberg mill was selected as a case study because of low current levels of synchronization. Growers were assumed to operate independent harvesting and transport systems causing inconsistent convergences at the mill. This diverse and fragmented system provided a suitable environment to construct a model that would consider interactions between individual growers and their respective transport systems. Ideally, by assessing the micro-decisions of individuals and how they influence the larger holistic supply chain, TranSwarm quantifies the impacts of different types of transport practices, such as staggering shift changes, transport scheduling, core sampling and consortium-based logistics. TranSwarm is visual, mechanistic and represents key entities, such as roads, farm groupings and the mill. The system uses discrete events to create a dynamic and stochastic environment from which observations and conclusions can be drawn. This approach potentially allows stakeholders to identify key components and interactions that may jeopardize overall efficiency and to use the system to test new working protocols and logistics rules for improving the supply chain. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2008.

Inheritance studies have previously been undertaken at the South African Sugar Association Experiment Station (SASEX) under irrigated conditions. Since most sugarcane is grown in South Africa under dryland (raingrown) conditions, heritability estimates were calculated under these conditions in this study and compared to those previously obtained under irrigated conditions. A sugarcane population consisting of 12 crosses, 32 offspring in each cross, and their parents were planted in the first two selection stages of the SASEX selection programme to ascertain which stage provided the most useful information when selecting parent cultivars. Data collected from Stage 2 was more reliable than data collected from Stage 1. Variance components, narrow and broad sense heritabilities, correlations among traits, and clonal repeatabilities between seasons were determined for 11 sugarcane traits at Stages 1 and 2. These traits studied included: stalk population; stalk diameter; stalk height; cane mass; dry matter % cane; fibre % cane; brix % cane; brix % dry matter; purity; pol % cane; and ers % cane. Narrow sense heritabilities of the sugarcane traits were estimated by mid-parent offspring regression . Alternative heritability estimates were obtained through restricted maximum likelihood (REML) analysis of the unbalanced North Carolina design II at Stage 2. Although narrow sense heritabilities determined by mid-parent-offspring regression were comparable with those previously determined at SASEX and by other workers, REML was more efficient than regression. Use of REML enabled additive and non-additive genetic variance components to be estimated by allocating degrees of freedom to treatments and the interactions between the different treatments. Heritability estimates varied for different traits and compared favourably with those obtained under irrigated conditions and by other workers. Additive genetic variance was more important than non-additive genetic variance for some characters, but not for stalk population, cane mass, and dry matter % cane, for which both variances were important. Selection of parent cultivars for all sucrose-related traits, fibre % cane, and stalk diameter should be as successful under raingrown as under irrigated conditions, provided that the environmental variation is determined efficiently under raingrown conditions. Environmental correlations were observed between some traits, particularly between the yield related traits, and may have influenced heritability estimates for those traits determined by mid-parent offspring regression. Stalk diameter, fibre % cane, and brix % dry matter were the most repeatable traits between seasons. Cane mass was the least repeatable trait between Stages 1 and 2 but was highly repeatable between plant (-P) and ratoon (-R) crops of Stage 2. Stalk diameter was positively correlated with brix % dry matter (0.457-P and 0.623-R) and strongly negatively correlated with stalk population (-0.790-P and -0.711-R) and fibre % cane (-0.628-P and -0.651-R). Cane mass was strongly positively correlated with brix % dry matter (0.638-P and 0.679-R). By selecting for brix % dry matter and stalk diameter, indirect selection for cane mass would be possible. Brix % dry matter was determined as the most reliable trait on which to base parental and commercial cultivar selection because it was highly heritable, highly repeatable and highly positively correlated with stalk diameter and cane mass. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1995.

The implementation of the National Water Act (1998) requires significant changes in the institutional arrangements for water management and, to cater for human and environmental needs, as well as addressing historical inequities, water allocations to irrigated agriculture are likely to be affected. As a result, farmers are facing increasing pressure to use water more effectively, to justify existing water requirements and to budget and plan with growing uncertainty regarding water availability. Therefore, a tool to manage and assess catchment water supply and demand interactions and the associated impacts on the profitability of irrigated sugarcane would be of great value. Although there have been several independent model developments in the fields of water management and sugarcane growth, none provide the required management information in an integrated manner. However, these models provide the foundation for the development of the required modelling tool. An irrigation model for sugarcane, ACRUCane, was developed and incorporated into the ACRU2000 modelling system. The water budget simulated by ACRUCane is linked to a surrounding catchment, the hydrology of which is simulated by the ACRU model. In doing so, a tool has been developed that has the capacity to: • model the soil water balance at a field scale for irrigated areas and at a catchment scale for non-irrigated areas, • link an accurate estimation of crop water requirement for an irrigated area with the availability ofwater at a catchment scale, • explicitly account for the impact of the performance of different irrigation systems on the hydrology and, ultimately, on the sugarcane yield of an irrigated area, • assess the impact of different supply constraints on sugarcane yield, and • estimate both sugarcane and sucrose yield. Extensive verification of the model has been undertaken using data from an irrigation trial at La Mercy, South Africa and two separate trials conducted in the Lowveld of Zimbabwe, with the primary objective of the verification studies being to assess the model's ability to account for different scheduling strategies on sugarcane and sucrose yield. The results obtained show that the model accurately captured the relative differences in yield associated with different irrigation treatments and can thus be used evaluate the impact of different scheduling strategies. A case study was conducted where the feasibility of several hypothetical irrigation scenarios were compared. Different scenarios were created by varying application uniformity, scheduling strategies and system type. This case study illustrated how ACRUCane can be used to provide reliable decision support information to irrigators. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2005.

Typescript (photocopy) / Thesis (Ph. D.)--University of Hawaii at Manoa, 1980. / Bibliography: leaves 219-232. / Microfiche. / xxi, 232 leaves, bound ill. 28 cm

Made available in DSpace on 2014-06-11T19:24:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-27Bitstream added on 2014-06-13T19:31:25Z : No. of bitstreams: 1 morais_aps_me_botfca.pdf: 687506 bytes, checksum: baad0742c0a39bca3a4a2b5908c9cedf (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / 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 / 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