Climate change and anthropogenic activities threaten our global food security. One area of research that may help combat a future food crisis is the utilization of the genetic diversity available in wild plants. Crop wild relatives (CWR) are one such resource. They are the wild taxa most closely related to crops and from which diverse traits could be transferred to the crop. This project uses Norway as an example, to contribute towards methodologies to identify those CWR populations that are most important for conservation and use. This involves the creation of a priority list of CWR for Norway, in situ and ex situ diversity analysis of CWR populations, gap analysis and ecogeographic land characterization methodologies, predictive climate change analysis for CWR distributions and genetic diversity studies of taxa using Amplified Fragment Length Polymorphisms (AFLPs). Comprehensive in situ and ex situ national recommendations for the conservation of CWR in Norway are detailed. These include the incorporation of management plans for CWR populations within the Færder national park in Norway, the first instance of such conservation activities in Scandinavia. The scientific methods used and developed will help Norway meet its international obligations for conservation and use of genetic diversity of CWR and will contribute to the regional and global efforts to systematically conserve and utilize the diversity found in CWR.

The dynamic interaction between different water sources plays a key role in the structure and functioning of Arctic stream systems. Ice melt, snowmelt, groundwater and rainfall mix to produce a diverse range of physicochemical conditions. The heterogeneous habitat matrix created is home to a variety of cold stenothermic species. Recent trends in earth surface temperatures associated with global warming have co-in sided with a reduction in global glacier mass balance and a hastening in the onset of spring thaw. This field based study investigated the physicochemical habitat diversity within a glacierized Arctic catchment, Kårsavagge in Northern Sweden. Hydrological, meteorological and physicochemical data spanning 2007 to 2010 were collected with intensive collection during the summer melt seasons of 2008 and 2009. In conjunction with these data, macroinvertebrate and fish sampling was carried out during both of the intensive summer monitoring periods. The key focus of the sampling regime was to compare lateral and longitudinal habitat variability, investigate the extent to which this was linked to dynamic water source interactions by modeling contributions from identified sources and assess the impact of this physicochemical habitat template on the macroinvertebrate and fish communities in the light of predicted climate change. The key findings discussed within are (1) Lateral habitat and biological diversity was equivalent to that observed longitudinally. (2) The ARISE framework used for modeling different water source contributions is applicable to an Arctic scenario, however its utility decreases with increasing catchment size. (3) The key habitat variables structuring macroinvertebrate and fish distribution were concerned with mediating/ mitigating the extent of the glacial signal. A conceptual model is presented that illustrates the potential impact of loss of this glacial signal on local biodiversity.

Triticeae Dumort. is a tribe within the Pooideae subfamily of Poaceae. Major crop genera found in this tribe include barley (Hordeum), wheat (Triticum) and rye (Secale) all of which are closely related to each other. In Turkey, with the several subgroups, this tribe is represented by 16 genera and 75 species, many of which have great economic values. The main objective of this research work is to determine the taxa of this tribe on the basis of their diagnostic anatomical characters of vegetative organs for the recognision of genera, sections, species, and infraspecific categories. By using both fresh and herbarium specimens, transverse sections of vegetative organs were obtained by using two different sectioning methods. This study covers both qualitative anatomical characters, such as sclerenchyma position, hair density and intercellular cavities of roots, shapes of leaves, presence of midrib, occurrence of leaf hairs, shapes of girders or strands, arrangement of sclerenchyma around vascular bundles and arrangement of epidermal cells, cell wall undulations, appearance of silica bodies, type of bulliform cells, arrangement of culm vascular bundles and their connections to the epidermis, hollowness of culms, as well as quantitative characters, such as sclerenchyma line number of roots, vascular bundle line numbers and diameters of culms, sclerenchyma line number of leaf margins, line numbers and sizes of all types of costal leaf hairs, stomata and interstomatal cell lines. In conclusion, all these properties are useful to understand both systematics and evolutionary relationships of the taxa. Moreover, the leaves of the tribe have the most numerous diagnostic characters. The roots do not have central metaxylem. The metaxylem elements are scattered in the vascular cylinder. The internodular parts of the culms may be hollowed or solid. However, the nodular parts of the culms generally have the same structure. Furthermore, there are two species which can be assigned as a subtribe.

Linum usitatissimum (flax), Brassica napus var. oleifera (oilseed rape), Miscanthus x giganteus (miscanthus) and Urtica dioica (nettle) were investigated to assess their potential as phytoremediation crops. Germination experiments using flax and oilseed rape established that seedling germination was not inhibited by exposure to metals in solution except at the highest concentrations considered. Germination was, however, not a reliable indicator of plant metal tolerance as metal toxicity to emerged seedlings was evident in contaminated soil treatments exhibiting good germination rates. Four plant species were grown in soils containing six metals at both highly and marginally spiked levels, to reproduce genuine contaminated soils whilst allowing the study of each metal in isolation. A sewage sludge treated soil with a high metal and organic matter content was also included in the study. Miscanthus was the species most tolerant of the highly contaminated soils. The highest tissue concentrations recorded in plants exposed to the highly contaminated soils were (969 mg Zn/kg) in stems of miscanthus and (919 mg Cd/kg) in stems of nettle, but plant growth in these soils was generally poor. The plant species survived well in the sewage sludge soil, although metal uptake from this matrix was low. Oilseed rape and nettle accumulated the highest tissue metal concentrations in the study of marginally contaminated soils. Indeed the highest tissue concentration recorded for plants grown in all of the soils was found in nettle grown in the marginally contaminated Zn soils (1937 mg/g). Miscanthus, was able to remove a greater weight of metal from the soil owing to its higher biomass, despite having a lower tissue metal concentration than the other species. Flax, miscanthus, nettle and oilseed rape have been shown to have potential to act as part of a phytoremediation programme, however, more work with these crops is required before film advice can be given on commercial application of the crops in contaminated land remediation.

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This thesis analyses how Andean people’s knowledge of medicinal plants and the relationship between environment and health is represented, transmitted and commoditised in the marketplaces of the department of Oruro, Bolivia. Considering the increase in urban population and their dependence on marketplaces for medicinal plant remedies, this thesis examines the role of marketplaces and the importance of specialist stallholders in the transmission of knowledge. The central research site of Oruro is a multi-cultural city located on the Andean plateau in southwest Bolivia, a population of Spanish, Quechua and Aymara speakers with a pluralistic medical system. Fieldwork was carried out over 18 months with market stallholders in Oruro combining quantitative and qualitative methods with ethnographic documentation of knowledge transmission events. This thesis found that medicinal plant marketplaces in Oruro are highly regulated social systems that incorporate Andean socio-economic mechanisms, including ritual performance for the transmission of cultural knowledge, and the regulation of resource distribution and use. The development of a ‘chemical landscape’ model demonstrated that social exchange and trade between ecosystems and altitudinal zones broadens the spectrum of medicinal compounds available, contributes to the complexity of herbal mixtures and can limit exploitation of local plant populations. The market stallholders use specialist classifications that identify chemical properties, toxicity and variations between plant species and ecological regions. Plant classifications varied with the context and location in which they were used, and humoral classification enabled the selection and combination of plants in mixtures and justified remedy efficacy for specialists and non-specialists. Andean cultural beliefs including complementary opposites enabled transmission of knowledge on the medicinal properties of plants between highland consumers and lowland producers, and defined traditional Andean mixture efficacy. These findings demonstrate that, although state intervention and identity politics are redefining perceptions of medicinal knowledge, the market exchange system centred in Oruro city creates localised specialist knowledge and continuity of cultural knowledge transmission.

Plant performance under reduced water availability has traditionally been assessed as drought resistance and more recently as water use efficiency (WUE). An extensive body of work has been established over the past 15 years where the natural variation of water use efficiency has been studied in the model species Arabidopsis thaliana (Arabidopsis). At the same time, a substantial degree of criticism has arisen with respect to the use of drought resistance and WUE as measures of plant performance, due to the lack of relatedness of these parameters to reproductive performance, i.e. yield. The work in this thesis is centered on understanding the physiological and genetic basis of water use and water productivity as alternative measures of plant performance under the context of reduced water availability. The first part of this study describes an extensive assessment of the natural variation of water use and water productivity in Arabidopsis in relation to numerous key physiological, phenological, and developmental parameters. Furthermore, this work concisely relates plasticity of key traits to historical climatic variation. A fundamental aspect of this work was the clarification that it is possible to estimate long term water use to a high degree of accuracy based on short term water use, i.e. soil drying rate, and flowering time. Flowering time was demonstrated to be the predominant driver of vegetative performance and water use, however it appeared to be genetically uncoupled from reproductive performance. This is in contrast to previous work that suggests WUE, measured as the ratio of C12 to C13 isotopes (δ13C), is positively associated with flowering time. Additionally, it was demonstrated that multiple commonly employed proxies of reproductive performance including total biomass, WUE, and flowering time, were not sufficient at predicting seed yield in Arabidopsis across multiple environments. The second part of this study involved the genetic dissection of water use and productivity related traits in Arabidopsis through a quantitative trait loci (QTL) mapping study and a genome wide association study (GWAS). QTL mapping using a recombinant inbred line (RIL) population developed from the ecotypes Col-0 and C24 revealed two key flowering time genes, FLOWERING LOCUS C (FLC) and FRIGIDA (FRI), as key regulators of water use. It was demonstrated that a combination of non-functional alleles of both FLC and FRI reduced long term water use via a shorted life cycle, which is again in contrast to previous work relating to the genetic dissection of WUE in Arabidopsis. Crucially, it was observed that reduced water use mediated in this fashion did not detrimentally impact upon reproductive performance. GWAS was employed subsequent to the QTL mapping in order to identify candidate genes underlying the variation for productivity as a unique trait and also as a factor of water use, i.e. water productivity. GWAS identified multiple promising candidate genes that potentially underlie the heritable genetic variation for flowering time, water use, and water productivity.

Cardiovascular disease is a major killer worldwide and it is becoming clear the significance of our diet in curbing the disease. Green tea is one of the most widely consumed beverages in the world and has recently attracted significant attention in the scientific community for its health benefits. Its consumption has been associated with lower incidences of coronary artery diseases in the Japanese population. This is mainly attributed to its polyphenolic constituents that include epicatechin, epicatechin gallate, epigallocatechin and epigallocatechin gallate. The aim of this research was to synthesise the four major polyphenols present in green as well as analogues. These compounds would then be tested on H9C2 cardiac myoblast cells and neonatal rat cardiomyocytes in order to further understand the structure-activity relationship as well as potentially improve the cardioprotective function of these polyphenols following oxidative stress and ischaemia/reperfusion injury focusing on the expression of STAT-1 and ERK-1/2 proteins. In H9C2 cardiac myoblast cells following the induction of oxidative stress using H2O2, EGCG, EGC and to a minor extent ECG inhibited STAT-1 activation but not ERK- 1/2 phosphorylation suggesting that although the ERK-1/2 pathway gets activated, its downstream activation of STAT-1 is inhibited by the above polyphenols. EC, on the other hand, inhibited ERK-1/2 activation which in turn cannot activate STAT-1. Quantitative assessment of viable cells showed that pretreatment with EGCG resulted in the lowest amount of non-viable cells reducing cell death by 30%. With neonatal rat cardiomyocytes following ischaemia/reperfusion injury, pretreatment with EGCG reduced the amount of non viable cells by 5% but pretreatment with acetylated EGCG at half the concentration of EGCG reduced non-viable cells by 8%. Structure-activity relationships of the green tea polyphenol analogues identified some key aspects in the structures of the polyphenols important in their cardioprotective function. Results indicated that ABD ring system is required for cardioprotective function but the presence of a third OH group in the ring may not be necessary. Substitution of ring C with benzoic and naphthoic rings improved the potency by more than 13-fold compared to EGCG with EC50 values of 1.60 and 0.77 μM respectively. Further research into these analogues could realise their potential and contribute to the understanding of the cardioprotective activities of green tea. A review on the previous synthesis approaches, isolation and biosynthesis of the green tea polyphenols is presented in Chapter 1 and also the different signalling pathways of interest in this work. An evaluation of the biological activities of the four major polyphenols is provided in Chapter 3. Experimental procedure and characterisation data are in Chapter 5.

Ecosystems undergo permanent alteration and degradation as a result of the pressure exerted upon them by anthropogenic activities and natural causes. Amongst the natural causes, drought can have considerable impacts on vegetation productivity; these impacts include biomass reduction and changes in vegetation cycles, growth, and vitality. Such impacts have important implications for society, and understanding the impacts of drought in natural systems will help minimise vulnerability to it. The Yucatan Peninsula is a vulnerable area in climate change scenarios, where increased intensity and frequency of droughts is already occurring. This thesis aims to analyse how droughts impact upon vegetation on the Yucatan Peninsula, Mexico using both remotely sensed data (in particular the Advanced Very High Resolution Radiometer – AVHRR - data) and meteorological data (in situ precipitation data). Three major elements are addressed: (1) spatial and temporal precipitation variability, and the occurrence of droughts during the period 1980-2011; (2) vegetation productivity trends, focusing on the persistence and resilience of the different vegetation types present across the Yucatan Peninsula using remotely sensed data sets, specifically, the Normalised Difference Vegetation Index (NDVI) from the National Oceanic and Atmosphere Administration Advanced Very High Resolution Radiometer (NOAA-AVHRR) as a proxy for productivity in the period 1982 to 2011; and (3) the relationship between vegetation productivity and rainfall and the lack of it (i.e. droughts) at a more detailed temporal scale (monthly) with two vegetation indices (NDVI from AVHRR and MTCI from the MEdium Resolution Imaging Spectrometer (MERIS)). The main findings indicate that precipitation in the area follows a gradient from north to south which is linked to vegetation types in the area, from deciduous forest to evergreen forest. NDVI trends in the Yucatan Peninsula are generally stable during the period 1980-2011; however, negative trends are persistent in areas where human impacts and intensive agriculture are present. Analysis of resilience also shows that deciduous forest and grasslands are much less resilient to disturbance and have a longer recovery period compared to other vegetation types. Per-pixel regression analysis between precipitation and vegetation productivity shows high explained variances between NDVI and rainfall with a time-lag of 1 and 2 months and tropical dry forest is the biome most affected by droughts. These results are valuable for decreasing the vulnerability of the Yucatan Peninsula and they could be used for increasing the understanding of the area and therefore go further in the creation of warning and management programmes.

The action of ricin A chain on eukaryotic ribosomes was investigated from a number of different angles. It was shown that ricin A chain modified the rRNA from the 60S subunit of a number of eukaryotic ribosomes, including plant ribosomes, and that the site of action was at the same position in a highly conserved sequence which had previously been identified as the site of action in rat liver 28S rRNA. Investigations into the partial reactions of protein synthesis inhibited in ricin A chain-treated ribosomes showed that both initiation and elongation were inhibited, contradicting the assumption based on previous work that ricin A chain inhibited just the elongation cycle. In a rabbit reticulocyte lysate it was found that whilst elongation was severely inhibited by ricin A chain, the rate of initiation was also reduced approximately six-fold relative to that seen with an inhibitor of just elongation. Furthermore, experiments carried out to investigate the inhibition of elongation showed that this was most likely due to the inhibition of the elongation factor 2 catalysed step. Using an assay which allowed the N-glycosidase activity of ricin A chain to be measured directly it was possible to show that ribosomes from a number of different sources varied markedly in their sensitivity to ricin A chain. Wheat germ ribosomes were shown to be in the order of 1000 times less sensitive to modification than those from either yeast or rabbit reticulocytes. However, this difference does not seem to be a reflection of the differential affinity of ricin A chain for the various substrates but rather a consequence of the ability of the toxin to modify the rRNA once it has bound. This is because kinetic experiments showed that the Km for the reaction on wheat germ ribosomes was similar to that which had been published for the action of ricin A chain on rat liver or rabbit ribosomes. The Kcat, however, was approximately 3 orders of magnitude smaller. A similar picture was seen with the type 1 RIP dianthin 32. It was shown directly that elongation factor 2 bound irreversibly to the ribosome could protect the ribosome from the action of ricin A chain and that in a wheat germ lysate this ability to compete out ricin A chain seemed to be a property of just this supernatant protein. This protection is reflected in the finding that the elongation factor 2 content of purified ribosomes determines their sensitivity to depurination by ricin A chain and that the removal of this protein with high salt sensitises the ribosomes to modification.