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ISSCT XXVIth CONGRESS Durban, South Africa 29th July - 2nd August 2007 |
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PLENARY PAPERS
abstracts
PL12_final KEYWORDS: sustainability, integrated management, farming systems, management framework Abstract In recent times there has been considerable national and international focus on the sustainability and productivity of the world’s sugarcane growing industries. Concerns have been raised about exploitive management practices with critics suggesting that the world’s sugarcane production systems are focussed almost solely on productivity. In particular, criticism of the environmental sustainability issues has received substantial publicity. In this paper, we analyse the research, development and adoption of improved sugarcane production systems worldwide and opportunities for further improvement. Key benefits of adoption are identified and supported by case studies. Further, we argue that sustainability will not be achieved without profitability and will only be achieved in a socially equitable environment. Within this broad context of sustainability (profitability, environmental sustainability and social equity), we believe that worldwide sugarcane production systems can be implemented that are no more exploitive than any other agricultural production systems. In this review we propose a framework of seven key topics that can be used to guide the identification and application of better management practices in sugarcane fields. These topics include soil management, crop management, water management, pest and disease management, workplace health and safety, recognition of heritage and conservation principles and business management. We believe this framework has international relevance, but the importance of risk, opportunities and response mechanisms will vary between industries and regions.
PL13 Abstract Climate change is a reality worldwide, and in many respects more so in South Africa where it will be superimposed onto an already high risk climatic environment. This presentation highlights the most recent findings of the Intergovernmental Panel on Climate Change in a South African context and then assesses plausible scenarios of climate change in light of potential cane yield changes, possible expansions and contractions of areas currently under sugarcane, as well as projected increases in pest/disease incidences and increased irrigation water demand. By way of conclusion, various adaptation strategies are then reviewed from a perspective of Best Management Practices
PL21_abstract KEYWORDS: sugarcane, energy, cogeneration, ethanol Abstract Sugarcane is a worldwide crop cultivated in more than 100 countries. With the exception of Brazil, it is essentially used as a food crop for the production of sugar in its many forms (raw and refined sugars, gur, panela, molasses, etc). Because of that, throughout the centuries, the new varieties and production process have been optimized for the increase of sucrose per hectare of cane field and the maximum recovery of this sucrose in the factory. Even in countries like Mauritius and Brazil, that are extracting considerable amounts of energy from the cane, the main product is still the sugar. Recently, several other countries are starting to look at sugarcane as a source of both food and energy; it may be the beginning of the transition from cane for sugar to energy cane. In this respect, the primary energy contained in the cane and the efficiency of the conversion of this energy to useful forms of secondary energy are going to be as important as the pol % cane and the factory recovery are today. This work analyses the present energy potential of sugarcane and the conversion efficiencies, and tries to project the data to 2020, considering the gains in agricultural productivity, factory efficiency and the phase in of emerging technologies, such as gasification, hydrolysis and biomass to liquid (BTL), especially to achieve the conversion of the fibres to electricity and liquid fuels.
PL22_abstract KEYWORDS: Gene expression, metabolism, metabolic flux, precision breeding, resistance. Abstract For centuries sugarcane has primarily been used for the production of sucrose. Conventional breeding programs have therefore concentrated on sucrose content and sucrose yield per area of land. There is an increasing realisation that sugarcane processing can deliver additional high value products. The success of a biorefinery is directly linked to the quality of the feedstock i.e. if the desired end-product is not directly present then there must be suitable precursors for conversion. Theoretically, precision breeding (PB) allows for the modification of existing metabolic pathways and/or the addition of novel metabolic steps. Several institutions worldwide now have the ability to genetically modify sugarcane by up or down regulation of current genes, or the insertion of new genes. In addition, there are large databases which provide a good indication of expression of the current genome. This allows for the targeting of specific reaction steps, but also indicates the number of reaction steps that might be needed to produce a novel product. What we have learned from sugarcane precision breeding during the past decade is that (1) novel proteins can be expressed at significant levels, (2) new traits such as pest, disease and herbicide resistance can be added, (3) the maximum catalytic capacity of targeted enzymes can be altered, (4) that the outcome of these metabolic perturbations are unpredictable and varied, and (5) that the genetic modification often results in decreased biomass production. Future genetic improvement of sugarcane as an ideal feedstock for biorefineries will rely heavily on an improved understanding of metabolic control and flux, cellular compartmentation and availability of metabolites, and the ability to better identify potential targets for PB. The latter will be dependent on metabolic and enzyme profiling and the ability to accurately model cellular metabolism.
PL23_abstract KEYWORDS: sugarcane, biomass, ethanol, biorefinery, conversion Abstract The conversion of a sugar mill into a multi-product sugarcane processing plant or biorefinery holds substantial potential for improving profitability in a sustainable way. This envisages a sugar mill producing not only sugar but a range of products which significantly improves its revenue stream. As well as products for direct use (e.g. ethanol), a biorefinery may also produce a range of chemical intermediates which represent the feedstocks for other products, in a similar way to the production of chemical feedstocks in an oil refinery. This paper considers the options for potential products and the processing steps necessary for the objectives to be realized. The optimum feedstock for a biorefinery could be significantly different from traditional sugarcane, bred for biomass not sucrose, and possibly augmented with other agricultural feedstocks. The present obstacles to the implementation of biorefinery schemes involving fractionation and hydrolysis of lignocellulosics as well as thermochemical treatments are identified. Economies of scale point toward the implementation of large plants to achieve economic viability. However, selected add-on options depending on the economics of individual processes provide the route for converting a sugar mill into a biorefinery in smaller, less capital-intensive steps. The successful implementation of some of the processing schemes discussed here could see a more profitable, diversified and expanded sugarcane processing industry.
PL31_abstract KEYWORDS: Sugar, Fuel Ethanol, Policy, Markets, Trade, Commodities Abstract The sharp sugar price rally in January-April 2006, when prices climbed to 25 year highs saw producers, traders, speculators and analysts in a euphoric mood. This optimism was driven by structural reform in the EU sugar sector, rising global fuel ethanol demand and perceived under-investment outside Brazil. The safety cushion of high global stock levels, characteristic of the previous decade, had seemingly disappeared. Analysts warned that any crop shortfall in 2006/07 could lead to noticeably higher world prices. This was not to be and, instead, prices in New York have steadily weakened to below 10 US cents/lb. Sugar fundamentals have played a major role in the decline. Good weather and strong investment in the sector following the higher prices have boosted global sugar production. Another contributing factor has been lower crude oil prices undermining hopes that significantly more cane would be used for global ethanol production in the short run. However, growing usage and trade in ethanol remains as a crucial new strategic driver. Indeed, the emerging interface between sugar and ethanol, and therefore crude oil, should only gain in importance. Potential EU imports under the EBA and EPA initiatives, as well as possible changes to sugar policy in the next US farm bill and developments in the WTO Doha Round negotiations on agriculture, are all key strategic drivers for the world sugar market. The rapidly expanding capacity of large destination refineries will boost raw sugar trade, but at the same time there is an emerging trade in lower quality white sugar. The ability of Brazil to expand to meet growing global demand for sugar and ethanol is also a key factor for the future. Each of these strategic drivers is reviewed and analysed in this paper with a view to understanding their impacts on the outlook for the *Whilst drawing upon published ISO research and analysis, the views expressed in this paper are those of the author and in no way represent official views of the International Sugar Organization or of any of its members. |
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