In urban areas surfaces are sealed by stone, concrete, and tarmac and there is a limited network of green areas. Consequently urban areas have higher temperatures, lower atmospheric humidity, and higher air pollution. By adopting green roofs in sufficient numbers in cities the quality of the urban environment could be significantly improved by cooling and improving the moisture content of the air, by extracting CO2 and pollutants and by attenuating rain water run-off. In Germany and Switzerland there is a well established and successful green roof industry that has developed steadily over many years. In contrast there are few green roofs in the UK. Yet the potential is huge, an estimated 20,000 hectares of existing urban roofs in the UK could be vegetated with little or no structural modification (Corus: 2001). Furthermore, roof gardens and terraces could offer an increasingly valued green space in cities where populations are growing and where it is becoming difficult to afford land on the ground. This qualitative study aims to discover why recent existing urban green roofs were adopted and how this uptake was affected by the perceived benefits and barriers set out in the report. The study tests a possible research design, which could be used to explore the main research themes and questions. To explore these themes and potential designs the research uses the exploratory case study method. Three very different buildings with green roofs were used these are all situated in British cities and were all built between 1999 and 2004. The buildings include Greenside Place in Edinburgh, BedZED in London and the National Wildflower Centre in Liverpool. The drivers for the adoption of each green roof match the theoretical drivers and benefits, as do the barriers. Where the green roofs have been adopted, no known, significant barriers exist. Although the roofs are not entirely problem free, for example, some plants on the roofs have suffered in the exposed conditions, on the whole, the studied roofs are well received and considered successful by stakeholder members.

Cultivars are traditionally identified by morphological and phenological characters during the growing season. However outside of the growing season and with an enormous number of cultivars this is often unfeasible. Molecular techniques, especially microsatellite analysis, offer potentially effective and cheap methods for cultivar identification. Complex breeding programmes of daffodils over the past 150 years have resulted in more than 30,000 cultivars. Despite the economic importance of daffodils the taxonomy of the genus is unresolved. This thesis aims to evaluate the use of microsatellites in Narcissus for cultivar identification and taxonomic revision, in combination with DNA sequencing, using hoop-petticoat daffodils as a model system. Three field trips were conducted to discover the natural variation within section Bulbocodii. A total of 455 samples were analysed from across the natural range. Twenty-four Division 10 cultivars and five wild-type hooppetticoat daffodils were sourced from commerce. A new microsatellite library of eleven loci was developed. All of the hoop-petticoat daffod ils could be genotyped. The transferability of the microsatellite markers was tested on 18 additional daffodil species. Transferability ranged from 39% to 100%. A part of matK was sequenced to help identify hybrids both in the wild and amongst cultivars. Of the naturally occurring species Narcissus bulbocodium, N. hedraeanthus and N. obesus could be identified. The remaining two species N. cantabricus and N. romieuxii could be separated from the other taxa, but not from each other. Twenty-two out of the 24 cultivars could be identified. The molecular markers proved useful in the identification of mislabelled plants. The microsatellites were also tested on 54 non-Division 10 cultivars. Eight out of 11 microsatellite loci could be transferred to at least 94% of the samples. Additional microsatellite markers couid be developed to provide resolution for over 30,000 daffodil cultivars. This project demonstrated that microsatellite markers could allow an objective evaluation of the taxonomic diversity of hoop-petticoat daffodils and their cultivars.

No description available.

Whilst not a ‘new’ pest in the UK, Aleyrodes proletella has become an increasing problem for the Brassica industry in recent years, especially on Brussels sprout and kale. The reason for the increasing problem is unknown, but it is believed to be due to a combination of climate change, removal of certain active ingredients from use and later harvest times of crops. Relatively little research has focused on this species as, historically; it has been regarded as a minor pest. Knowledge about the biology of A. proletella is limited and some of what is currently understood about its ecology has been inferred from anecdotal evidence. The overall aim of this project is to understand population trends of A. proletella in the most vulnerable crops, Brussels sprout and kale. This includes understanding the key times of population increase and colonisation of new crops. This information can then be used to inform the development of an integrated control strategy using insecticides and other tools, which might include biological control agents and methods of cultural or physical control. Experiments to investigate the vertical and horizontal distribution of flights by A. proletella showed that A. proletella performs mainly low, short distance flights throughout most of the year and it is these flights that are mostly responsible for colonisation of new vulnerable crops, which can be achieved by overwintering females early in the season. Monitoring of field populations on kale has shown that populations of whitefly develop without regulation by predators or parasitoids, with increases in numbers mostly determined by the development of further generations from the initial immigrants to the crop. The size of a population of A. proletella that can be achieved within a crop seems to be governed by the number of generations that can develop before the onset of diapause in September, which prevents further reproduction. A new fungal pathogen, which causes epizootics within the field, has been observed. This killed up to >90% of adult A. proletella. Of all potential natural enemies this pathogen had the largest potential to reduce A. proletella infestations and offers potential for the development of a new method of biological control.

The genus Antirrhinum (commonly known as snapdragons) contains more than twentyfive recognised species. The genus has been divided into three morphological subsections: Antirrhinum, Streptosepalum and Kickxiella (Rothmaler, 1956). One of the major characteristics distinguishing the three subsections is flower colour. Most species in subsection Antirrhinum have dark pink or yellow flowers, Kickxiella species are white or pale pink and Streptosepalum species have yellow or pale pink flowers. All Antirrhinum species can be crossed to produce fertile hybrids which allow the genes that underlie their differences to be identified. I used quantitative trait locus (QTL) analysis on hybrids of A. majus (dark magenta flowers) and A. charidemi (pale-pink flowers) to map genomic regions underlying differences in flower colour. This identified two major-effect loci, in Linkage Group 3 (LG3) and LG7, that explained most of the differences between these species. I used near-isogenic lines (NILs) to further test involvement of two candidate genes - Rosea (Ros) in LG3, which encodes a regulator of the anthocyanin biosynthesis pathway (ABP) and Incolorata (Inc) in LG7 which encodes a rate-limiting enzyme of the ABP. In both cases, the A. majus allele increased pigmentation. Sequence differences between Ros alleles of A. majus, A. charidemi and A. molle (a Kickxiella species with white flowers) suggest that A. molle carries a ros loss-of-function mutation and that a transposon insertion in the ROS promoter might contribute to differences in expression between A. majus and A. charidemi. Ros genotypes were found to be strongly correlated with pigmentation in the corolla tube in A. majus x A. charidemi hybrids, and to a lesser extent with corolla lobe pigmentation, although NILs suggested that ROS did not correspond to the major-effect QTL indentified in LG3. I also mapped a minor-effect QTL for tube pigmentation to a region of LG4 containing the ABP structural gene Candica. Analysis of NILs revealed that Inc was not the second major-effect QTL mapped to LG7, although sequence differences were detected between Inc alleles of A. majus and A. charidemi. I was further able to narrow down the region containing the second LG7 major-effect QTL to an interval of 11 cM, between two molecular markers, which could be used to determine the likely QTL genotypes of segregating NILs. Surprisingly, several ABP genes, particularly Nivea, Inc and Pallida, were expressed at higher levels in pale flowers that were homozygous for the A. chardemi QTL allele than in their dark flowered siblings that carried an A. majus allele. This suggests that ABP genes might be up-regulated in pale flowers as part of a negative feedback mechanism. Two potential roles of the LG7 QTL are considered 1) its requirement for anthocyanin modification or transport to the vacuole, so that a build-up of cytosolic anthocyanins or their break-down products in pale flowers increases structural gene expression but cannot compensate for the overall reduction in anthocyanin, or 2) a role in promoting production of flavonols at the expense of anthocyanins.

The issue of skin friction related injuries has been one of the problems challenging the artificial sports turf industry. It has been identified by users as a major factor impeding acceptance of artificial turf at the professional level. However, information explaining the mechanisms for skin-turf abrasion is limited and little progress has been made, it appears, to derive an appropriate testing method for product approval or in evidence of improvement of the skin-friendliness of these products in sport surface surfaces. This research project focused on exploring the potential for improving the skin-friendliness of artificial turfs through a multi-faceted approach: identifying the contribution of the abrasive-components in modern artificial turf surfaces through mechanical testing; while critically evaluating currently available skin friction standards , evaluating strategies for polymer material modifications to reduce the skin-surface friction; and the designing of an appropriate bench-top set-up for the lab-based assessment of material skin-friendliness. The lack of understanding of skin-turf interaction was addressed by identifying the turf-component that has the greatest influence on the skin-turf friction with the mechanical device used in the current industry standard. The skin -turf frictional profiles of a series of third generation (3G) turf surfaces were examined, in combination with independent measurements of the silicone skin surface roughness pre- and post-friction testing. Results indicated that turf carpets without any infill material exhibited the highest frictional values while surfaces completely filled with either sand or rubber displayed similarly low frictional values, independent of infill type. Morphological measurements also showed the largest decrease in surface roughness for skin samples tested on carpet-only surfaces, indicating a smoothening effect via abrasion. This abrading effect is alleviated with the addition of infill to the surface, with fully-filled surfaces having the least damage to the skin s. This unprecedented study suggests that the carpet may have the largest influence on the overall frictional behaviour of an artificial turf surface narrowing down the turf component to be targeted when applying product improvements to address skin-friendly properties. The strategy of material surface modification was then employed, to study the effect of polyzwitterionic brushes on improving the skin-friendliness of the identified polypropylene substrate. To address the intended application for artificial turfs, a bench-top test was developed to investigate the frictional properties of the hydrated samples outside of commonly used aqueous environments, where an excess of lubricating water molecules is absent. Photo-grafted poly(sulfobetaine methacrylate) (pSBMA) brushes of various irradiation durations were prepared and the improvement in frictional properties was studied. Frictional measurements using silicone skin tips, under both dry and hydrated surface conditions, showed that the applied modification was capable of forming a stable lubrication layer in the absence of excess water, significantly reducing the coefficient of friction by up to 78.8 %. The pSBMA brushes also provided the additional advantage of antifouling exhibiting resistance towards pathogenic Staphylococcus aureus with almost zero surface colonization for well-grafted samples. The low skin -sample friction under ambient conditions and desirable fouling-resistance highlights the potential of pSBMA brushes as a modification strategy for achieving skin-friendly surfaces targeted at reducing the risk of skin abrasions. The tribological implications of counter-surface selection were investigated. Frictional assessments of the pSBMA-modified samples were carried out using standard steel tribo-tips, in addition to the skin tips used. Measurements with the skin tips showed that the hydrated pSBMA brushes were successful in reducing initial skin -sample friction though the effect diminishes with extended testing, attributed to the drying of the interfacial water. The standard steel tribo-tips were unable to reciprocate these results, returning consistently low frictional values regardless of extent of surface modification or hydration. These observations draw attention to the importance of counter-surface selection in frictional assessments, highlighting how appropriate test materials can identify characteristic surface properties while providing an interaction that simulates that of the intended application. The simple experimental set-up used may potentially be enhanced as an intermediate product qualification method in the manufacturing of skin-friendly artificial turf yarns.

Alstroemeria is an important cut flower and its breeding has been developed focused on aesthetic characteristics and vase life longevity, but little is known about its scent. Five different genotypes were assessed including the non scented cultivars ‘Rebecca’ and ‘Samora’ and the scented cultivars, ‘Sweet Laura’, ‘Ajax’ and the species A. caryophyllaea. The scented Alstroemerias emitted the terpenoids: isocaryophyllene and ocimene as the major floral volatile compounds. Characterization of an Alstroemeria TPS (ALSTER) was based on four ESTs previously found in A. cv ‘Rebecca’. Rapid amplification of cDNA ends (RACE) was performed and the full length ORF was used for characterizations of the genomic organization and amino acid sequences (phylogenetic analysis). ALSTER genomic region contains five introns and six exons. This unique genomic organization classified ALSTER as a member of the class III with a merged 5-6 exon. The deduced amino acid sequence was classified into the subfamily TPS-b. A functional analysis showed enzymatic activity of ALSTER with geranyl diphosphate (GPP) and the monoterpene myrcene was the only product obtained. Gene expression evaluated through real time and semi q RT-PCR on eight different stages of development (SO to S7) showed high expression of ALSTER at around S2 - S4 in the scented Alstroemerias, coinciding with high scent emission perceived and also with the maturation of reproductive organs. Evaluations through surveys focused on level of liking of floral scent, were performed finding positive correlations between floral scent liking and floral appearance liking and between floral scent liking and floral scent intensity. Finally, 17 new lines of A. caryophyllaea were evaluated in terms of their morphology, phenology and productivity. Although none of them were suitable for the market because of their low productivity, short stems and small flowers, they were all scented and identified as promising starting points for breeding purposes.

Palms support the largest leaves in the world and have evolved on Earth for over 120 million years. They are often reported to be the only structure left standing post-hurricane. Cross-sectional shapes of cantilevered structures are important design factors affecting torsional and bending performance. Understanding the shape contribution of natural sections such as palm petioles (modified leaf stalks) is more difficult than those for simple 2D shapes because conventional methods of calculating section properties are not well suited to these irregular shapes. The role of internal structure, material properties and external shape of palm petioles in cantilever performance has been investigated and three main contributions to knowledge result from this research. Firstly, 3D mapping, i.e., the size, orientation and position, of vascular bundles in the Trachycarpus fortunei palm petiole reveals the distributions of stress and Young’s modulus values, providing a more detailed understanding of petioles than previous work. Secondly, bulk elastic material properties along the longitudinal axis of the same petiole are then input to a bi-layered model of the same petiole establishing the Young’s modulus of the two layers without mechanically testing them individually and for determining that the outer layer is not lignified. Thirdly, the largest contribution is the introduction of modified shape transformers employing the use of circular envelopes, eliminating error caused by approximating second moment of area with the torsional constant. This leads to a novel Shape Edge Mapping (SEM) technique which deconstructs petiole cross section shape elements and enables the structural contribution of these elements to be calculated, improving the understanding of the petiole section and how it relates to its mechanical function. This thesis makes a valuable addition to the knowledge of palm function and presents novel techniques for non-destructive extraction of natural shape data for abstraction and use in preliminary engineering design.