More than 70% of Ghanaian farmers depend on cassava farming and processing as part of their livelihood activities. The study sought to identify the actors in the cassava value chains, how their livelihood features influence upgrading in the value chains and also, factors that farmers consider in deciding whether to sell fresh cassava roots to intermediate processors or to process the roots themselves and sell. The study was conducted in locations in six districts in Ghana. It combined the Value Chain Approach and the Sustainable Livelihoods Approach using qualitative and quantitative data. A stakeholder workshop was held to identify the main actors and their functions in the fufu, kokonte and cassava flour value chains. Livelihood analysis was conducted in two parts. First, it was carried out on eighty (80) households in the pounded fufu and kokonte value chains and the second aspect involved an intermediary flour processor – Amasa Agro Processing Company Limited and 43 individual farmers who supplied cassava roots to the Company. A cost benefit analysis was also carried out to determine whether selling of cassava roots is more profitable than processing the roots into shelf-stable products for sale. It was observed that farmers and processors, who are the main actors in the identified value chains, did not have adequate access to physical, social, natural, financial and human capital. Livelihood features that enhanced prospects for upgrading in the fufu value chain were increased access to energy, water and sanitation, group membership, access to information, and a vibrant enabling environment. Three livelihood constraints, poor access to credit, labour shortage and inadequate transport facilities have however, been found to create circumstances favourable to adoption of the new technology in the fufu value chain. In the kokonte value chain, it was observed that access to health facilities, improved transportation, group membership, access to information and an enabling environment enhanced prospects for upgrading. It was also observed that farmers made more profit when they processed their cassava and sold it than when they sell the cassava roots to the intermediary processor. Among the processed products, profits from grits were found to be the highest, followed by agbelima and gari. However, farmers indicated that they are more comfortable selling cassava roots and grits to the intermediary HQCF processor than middlemen and other buyers because in addition to bulk and prompt payment, they have their fields ploughed for them on credit basis and also get free cassava planting materials. To promote the adoption of new cassava-processing technologies in Ghana and elsewhere in Africa, strategies recommended were the provision of financial assistance, improving access to information through extension services, development of manual and cheaper kokonte slicing machines and legislation on the use of a percentage of High Quality Cassava Flour as a substitute to wheat flour in the baking industry.

The enzyme L-asparaginase (L-asparagine amidohydrolase EC 3.5.1.1) has been shown to possess antitumour activity and has been extensively used over many years for the treatment of childhood acute lymphoblastic leukaemia. Today, this enzyme is produced commercially from either the enteric bacterium Escherichia coll or the plant pathogen Erwinla chrysanthemi NCPPB 1066. The following sections of this chapter have been written in the form of a review which summarises the available literature concerning L- asparaginase. The clinical, physical, biochemical, commercial and regulatory aspects of this enzyme are discussed, with particular emphasis on the chemotherapeutic L-asparaginase from Er. chrysanthemi NCPPB 1066, since this is the subject of the present study, in addition, the reader is introduced to the genus Erwinla and to the variety of tools that have been developed for the genetic analysis of a number of Erwinia species.

Wheat (Triticum spp.) is a particularly important crop for food security, providing 20% of worldwide calorie intake. Food production is not meeting the projected global demand of an increase of 2.4% p.a. Improvement of resource capture in wheat could help meet this demand. Nitrogen (N) is an essential macronutrient for plant growth and development; however, nitrogen use efficiency (NUE) for cereal production is only 33%. Domestication of modern varieties of wheat may have lost potentially beneficial agronomic traits, particularly in the root system. Optimisation of root system architecture could profoundly improve nitrogen uptake efficiency (NUpE) and in turn increase the yield potential of the crop. Using ancestral wheat germplasm and mapping populations, desirable traits may be identified and bred back into commercial wheat varieties to increase yield potential. Using a high-throughput hydroponic root phenotyping system, N-dependent root traits have been identified in wheat mapping populations. Using transcriptomic analyses, the gene expression profile of a candidate N-dependent root QTL has been identified. Using a new root phenotyping system, X-ray micro-computed tomography (μCT), a three-dimensional representation of wheat roots can now be imaged in soil. A selection of the same mapping lines have been used for 3D μCT analysis based on field NUpE parameters to identify promising root traits in both seedlings and mature plants.

In flowering plants, the opening of the anther to release pollen is carefully timed to maximise reproductive potential. Manipulation of this process is an important tool for plant breeding and the production of hybrid crops. Dehydration of the anther epidermis, combined with the presence of secondary thickening within the endothecium layer, is required to create biomechanical changes that enable anther dehiscence. Both passive and active processes contribute to the targeted removal of water from the anther walls, however the genetic factors controlling water movement are not known. Furthermore, the presence of stomata on anthers may enhance water loss via evaporation. In plants, active movement of water can be achieved by regulation of water channels and by changes to the osmotic potential of organs; this was explored in the context of changes in the anther driving anther dehiscence and pollen release. qRT-PCR analysis was used to identify aquaporin and sucrose transporter genes that are upregulated during anther dehiscence in Arabidopsis thaliana. For genes of interest, the phenotypes of available mutants were characterised. Combinations of single, double and triple mutants showed changes in fertility and variations in floral organ lengths. Analysis of GUS reporter lines showed that the promoter activity of different aquaporins is confined to specific parts of the flower. The results suggest that certain aquaporins isoforms enhance hydraulic conductivity in different parts of the flower, which could contribute to water transport required for petal and filament extension. The importance of evaporation during anther dehydration was also investigated. The phenotypes of Arabidopsis mutant lines with varying stomatal densities were characterised, and changes in fertility were investigated under different environmental conditions. High relative humidity delayed anther dehiscence and affected pollen viability, resulting in reduced fertility. Plants that have no anther stomata were most severely affected. These results suggest that water loss via evaporation is important for anther opening in Arabidopsis, and that the presence of stomata on anthers facilitates this process.

The female-produced sex pheromone for many aphid species comprises a mixture of the iridoids (4aS,7S,7aR)-nepetalactone (I) and (1R,4aS,7S,7aR)-nepetalactol (II). Plant-derived biosynthesis of I and II, in plant species such as Nepeta spp. (Lamiaceae) and Catharanthus spp. (Apocynaceae), respectively, has received considerable attention due to their role as precursors to many pharmacologically active compounds, including the indole alkaloids. To test the hypothesis that aphids biosynthesize I and II de novo similarly to that elucidated for plants, isotopic labelling techniques have been deployed with oviparous pea aphids, Acyrthosiphon pisum (Homoptera: Aphididae). A range of unlabelled and deuterium-labelled putative sex pheromone precursors were synthesised and applied to aphids via one of two methods; dietary incorporation or topical application. For feeding experiments, A. pisum oviparae were artificially fed using diet sachets. Under autumnal conditions, a simple aqueous 200 g/L D-sucrose solution, into which the compounds were dissolved, was found to sufficiently maintain oviparae. Topically-treated aphids were exposed to methanolic solutions of each compound by application of 0.2 μL onto their dorsal surface. Following treatment, the volatile organic compounds (VOCs) released by oviparae were collected by dynamic headspace collection and analysed by gas chromatography coupled to mass spectrometry (GC-MS) to confirm the presence and position of labelling. Using unlabelled derivatives to establish optimal VOC collection parameters, dietary incorporation of all deuterated putative precursors evaluated failed to achieve deuterium incorporation into lactol I and lactone II. Successful deuterium incorporation, as evidenced by the presence of molecular ions at m/z 172 and 170 (corresponding to 2H4-lactol I and 2H4-lactone II, respectively), was demonstrated following the topical application of [C-8,C-10]-deuterated C-8-oxidised geranyl and neryl derivatives. Conversely, deuterium incorporation was not evident using the citronellyl derivatives, highlighting the importance of 2,3-unsaturation during biosynthesis. Through the synthesis and application of [C-4,C-9-2H5]-labelled monoterpenyl derivatives, it was demonstrated that a kinetic isotope effect was not responsible for the lack of deuterium incorporation following application of deuterated monoterpenols and monoterpenals. To address unclarified aspects of lactol I and lactone II biosynthesis in aphids, such as precursor identity and cyclisation mechanism, the synthesis and purification of 8 hydroxymonoterpenol-8-β-D-glucoside and NADP2H probes was attempted but was unsuccessful. These results suggest that aphids follow a route to lactol I and lactone II that is also utilised by plants such as Catharanthus roseus (Apocynaceae). This work is expected to support future research into fully elucidating aphid sex pheromone biosynthesis, including identifying the genes, and therefore enzymes, involved. Future implications in the field of biotechnology-based iridoid synthesis and pest management are anticipated.

The aphid transmitted Polerovirus Turnip yellows virus (TuYV) was found to be widespread with high incidences in oilseed rape (OSR) across Europe. UK, France, Germany and Poland all having >90% TuYV incidence in some OSR crops. From the 179 whole TuYV genomes sequenced in this study the phylogenetic analyses indicated three distinct genetic groups in the UK, two of which were also detected in Europe. These three genotypes were also distinct from the original sequenced TuYV-FL. These groups are proposed to be distinct species due to their genetic distance based on the most variable gene ORF5 and phylogenetic analyses of ORF1, ORF3, ORF4 and ORF5. Mixed TuYV infection was uncommon and only two plant samples had genetically distinct isolates. Whole genome analysis also provided valuable information on two recombination hotspots located within TuYV genes ORF3 and ORF5. Investigation into the epidemiology of TuYV revealed many weed and crop species as hosts, including sugar beet, which it was previously thought not to infect. TuYV isolates detected infecting weed plants in the UK were successfully transmitted to OSR. Previously undescribed hosts, verbascum, geranium, teasel, spear thistle, dock and previously described hosts in the Brassicaceae, Compositae and Lepidium families were found in the UK. A full-length infectious clone of a UK isolate of TuYV has been produced, this will allow further assessment of TuYV in the future. The infectious clone was able to cause systemic infection of TuYV and was aphid transmissible. The Arabidopsis thaliana gene knock-out study did not reveal a single eIF gene or gene linked to virus movement or silencing that could provide extreme broad-spectrum resistance. The gene eIF(iso)4G.1 was able to give a broad-spectrum quantitative resistance, and the potential of eIF3D.2 as well as sucrose symporters SUC1 and SUC2 as candidates for extreme TuYV resistance were discovered. This understanding of the epidemiology and diversity of TuYV is being used to develop strategies for control.

Two of the major challenges to agriculture are the effective management of inputs involved in production and the impact of climate change on production. In Malaysia, as in other countries, input costs across rice farms within a particular year are highly variable, suggesting that there is scope for improving the efficiency of production. Climate change, particularly in the form of changed temperatures and rainfall, is likely to affect rice yields. In this thesis, we focus first on technical efficiency associated with rice producing farms in three granary areas in Malaysia. Technical efficiency (TE) was measured using non-parametric (DEA) and parametric approaches (SFA). For DEA, TE was analysed for the input-oriented approach in which inputs are minimised for a given level of rice production while for SFA, Translog production functions were used to represent the efficiency frontier of the industry. Primary data for a season of rice production were collected in 2010/ 2011; sample size was 100 farmers for each of three granaries: MADA, situated in the north of Peninsular Malaysia, KADA in the west and PBLS in North West Selangor. Results showed that, under the constant returns to scale (CRS) assumptions, KADA showed the lowest average efficiency at 65.2%. The other two granaries can also maintain output while reducing inputs: by approximately 27% in both cases. All efficiencies were greater under the variable returns to scale (VRS) assumption, with the differences between CRS and VRS values for KADA suggesting a considerable amount of scale inefficiency within this region. Results using the SFA approach were slightly higher as compared to TE from DEA. All methods used suggested that efficiency of rice production in Malaysia could be improved. Tobit regression was applied to indicate the relationship between TE and farm characteristics and management factors. Factors such as race, ownership, soils and variety were identified to have significant effects on the level of efficiency. With respect to climate change, to assess future rice yields, the DSSAT model was used to predict yields for the 2050s and 2080s by using generated weather data under alternative climate change scenarios. The results showed that climate change has a largely detrimental impact on rice yield in the future; the longer climate change exists, the worse the impact. For every 1% increase in temperature, yield was estimated to fall in a range of 7% to 21%. As yield was predicted to be less due to climate change, other things being equal, efficiency would fall as well. In Malaysia the rice industry has been sustained, in part, by government intervention, especially input subsidy. In the future, adaptation to climate change should have a higher priority, as should policies that help the industry to sustain itself through improved competitiveness rather than from government subsidy.

Heritage was defined as “what we value”, or “what we wish to pass on to future generations”, that is to say, heritage is not only a product of the past but also a valuable process in a culture (Deacon, 2003). Furthermore, the relationship between nature and culture is a defining problem for recent debates over the meanings of heritage after The 1972 UNESCO Convention. There is a centuries-old aesthetic discourse in Western culture that treats natural landscapes as objects of beauty, and this has influenced designations of natural heritage beyond human occupants, with the result that they are often considered desirable to conserve with traditional management practice (West & Ndlovu, 2010). The main standard for identifying heritage sites in the Western tradition, particularly Britain, France and Germany during the 19th Century, has formed a tangible perspective which is architectural style and historical significance including different views of power and dominance of particular civilisation (Jokilehto, 1990; Smith & Akagawa, 2009). Recently, recognising the significance of garden heritage has brought awareness of the crucial inputs needed to manage still existing garden heritage and to understand what we already have lost. Garden heritage is a vague term, embodying cultural landscape and tangible landscape. Managing garden heritage is a very important issue in passing our heritage to future generations. The main purpose of this study is to fully integrate the principles of management for intangible garden heritage connecting fabric and intangible assets within the Byeolseo garden which is a unique traditional form of the Korean garden. This study is based on the use of complementary research methods to address the relationship between local government perspectives and international ‘best practice’ concerning garden heritage values with their tangible and intangible aspects. How people establish value of garden heritage was main question that drove this study. As the detachment between local communities and their garden heritage site and the vanish of gardener and head gardener, this study aimed to re-connect between them with strategy for understanding garden heritage sites that respects the public perception of garden heritage. The cases of Byeolseo garden shows that people generally understand garden heritage in terms of significances. This study classifies six significances of gardens, but public perception of garden heritage should be formed by complex of these significances rather than individual significance, which is mostly found to be unclear to the public in South Korea. Therefore, this study encourage that the importance of the public appreciation of garden heritage sites depend on understanding their significance.

Targeted delivery of an active ingredient to plant systems required extensive studies in areas of soil mobility, plant root adhesion and encapsulation. To accomplish the aims of mobility and adhesion to roots, specific surface charges and colloidal forces are required. These charges are required to provide sufficient repulsive forces preventing adhesion to soil and attractive forces allowing adhesion to roots. To accomplish the aims of synthesising colloids for mobility, adhesion and also encapsulation we formed a specific strategy. We aimed to increase the anionic surface charge on colloidal nanoparticles as a means to aid mobility studies of colloids through soil by providing increased repulsive forces to prevent adhesion to both air interfaces and soil. We also designed a way to decorate colloidal nanoparticles with microgel particles thus forming a soft adhesive surface layer with which further functionality could be incorporated i.e. surface charges. Finally we designed a simple methodology for the encapsulation of oil with post functionalisation in mind. We synthesised colloidal nanoparticles, less than 200 nm, using soap-free emulsion polymerisation of styrene where up to 50 wt% of protected ethyl styrene sulphonate monomer was incorporated. The nanoparticles were hydrolysed to release the sulphonic charge using thermolysis in an autoclave. Soap-free emulsion polymerisation was used to synthesise raspberry-like and core-shell morphology decorated nanoparticles by the adhesion of crosslinked nanogel particles to a range of hydrophobic and hydrophilic seeds. Poly(acrylic) and poly(styrenic) seeds were synthesised with a range of hydrophobicities whereby more decoration of nanogel particles was achieved for hydrophilic seeds. The nanogel decoration was studied using di-, tri- and multi-functional acrylates and the morphologies changed from raspberry-like to core-shell as the functionality of the crosslinker increased. The presence of Vinyl functional groups was proved using Raman microscopy. Post functionalisation with different thiols was carried out using nucleophilic thiol-Michael addition chemistry and a loss of vinyl groups was shown. Encapsulation of aromatic oil was carried out using an interfacial thiol-Michael addition reaction between a tetra- functional thiol and a penta-/hexa- functional ene using an amine nucleophilic catalyst. A microfluidic device was used to control the capsule sizes and dispersity and light microscopy was used to study capsule sizes and dry-down properties. No rupture was observed for the millimetre and microcapsules produced but unfortunately size scale-down could not be accomplished for the current system using high shear homogenisation. In conclusion we increased the loading of sulphonate charge for colloidal poly(styrene) nanoparticles and we successfully increased the surface area of styrenic and acrylic seed nanoparticles using nanogel particle adhesion. We post functionalised decorated nanoparticles using thiol-Michael addition reactions and synthesised capsules using thiol-Michael addition reactions confined in a microfluidic device.

The potential impacts of climate change and environmental variability are already evident in most parts of the world, which is witnessing increasing temperature rates and prolonged flood or drought conditions that affect agriculture activities and nature-dependent livelihoods. This study was conducted in Mwanga District in the Kilimanjaro region of Tanzania to assess the nature and impacts of climate change and environmental variability on agriculture-dependent livelihoods and the adaptation strategies adopted by small-scale rural farmers. To attain its objective, the study employed a mixed methods approach in which both qualitative and quantitative techniques were used. The study shows that farmers are highly aware of their local environment and are conscious of the ways environmental changes affect their livelihoods. Farmers perceived that changes in climatic variables such as rainfall and temperature had occurred in their area over the period of three decades, and associated these changes with climate change and environmental variability. Farmers’ perceptions were confirmed by the evidence from rainfall and temperature data obtained from local and national weather stations, which showed that temperature and rainfall in the study area had become more variable over the past three decades. Farmers’ knowledge and perceptions of climate change vary depending on the location, age and gender of the respondents. The findings show that the farmers have limited understanding of the causes of climatic conditions and environmental variability, as some respondents associated climate change and environmental variability with social, cultural and religious factors. This study suggests that, despite the changing climatic conditions and environmental variability, farmers have developed and implemented a number of agriculture adaptation strategies that enable them to reduce their vulnerability to the changing conditions. The findings show that agriculture adaptation strategies employ both planned and autonomous adaptation strategies. However, the study shows that increasing drought conditions, rainfall variability, declining soil fertility and use of cheap farming technology are among the challenges that limit effective implementation of agriculture adaptation strategies. This study recommends further research on the varieties of drought-resilient crops, the development of small-scale irrigation schemes to reduce dependence on rain-fed agriculture, and the improvement of crop production in a given plot of land. In respect of the development of adaptation strategies, the study recommends the involvement of the local farmers and consideration of their knowledge and experience in the farming activities as well as the conditions of their local environment. Thus, the findings of this study may be helpful at various levels of decision making with regard to the development of climate change and environmental variability policies and strategies towards reducing farmers’ vulnerability to current and expected future changes.