This study was conducted to determine the role of flower-visiting bats as pollinators at the mangrove areas of Peninsular Malaysia. The mangrove trees of the genus Sonneratia, even though reported mainly pollinated by bats, are lacking in research regarding their pollination ecology. Therefore, the effectiveness of bats as pollinators was studied from the pollen loads on their bodies, as well as from pollen grains deposited on the stigmata during their visits to the Sonneratia flowers (Sonneratia 'caseoiaris, S. alba and S. ovata). Observations of other nocturnal visitors of the flowers were conducted to further assess the relative importance of bats as pollinators. The flowering biology of the three Sonneratia species was also examined to infer the breeding system and reproductive synchrony of the trees and their pollinators. Bats were the effective pollinators of S. caseolaris and S. alba trees, depositing sufficient pollen grains on the stigmata for pollination. The flowering biology of these two Sonneratia species (flower morphometrics, nectar secretion rate, nectar sugar concentration and anthesis phase) also suggests that these species uses bats as their principal pollinators. Even though the morphology of the S. alba flowers and visitor observations indicated pollination by moths such as sphingids, bats nonetheless were responsible for depositing most of the pollen loads on the stigmata of the flowers. Examinations of reproductive parts (pollen and ovules) indicated that the three species show obligate autogamy. Exclusion experiments on S. caseolaris however showed reduced pollination success when bats were deterred from visiting the flowers, further confirming the importance of bats as Sonneratia pollinating agents as compared to other visitors.

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Bird pollination is essential to the reproduction and survival of many plant species. Using the Australian bird pollination system, this thesis comprised three main areas of investigation: 1. "Pollination syndromes", which are convergent suites of floral traits, are traditionally thought to reflect specialisation on different pollinator types. However, the reliability of pollination syndromes in predicting pollinators has recently been questioned. 2. Virtually all studies of intra-specific variation in flower colouration in birdpollinated plants have focused on colour variation that is dramatic to human vision and have subjectively classified flower colouration using human vision. 3. Plant-pollinator interactions are threatened by anthropogenic activities, such as habitat loss and introductions of alien species.

Understanding the complex cellular courtship that occurs between the pollen and pistil tissues of flowering plants is a major goal for plant scientists. These pollen pistil interactions are characterised by a diverse range of molecules and processes, and many alternative mechanisms are employed by different species both to achieve successful pollination and to reject incompatible pollen. Due to their diverse nature, relatively little is known about these processes, and a general lack of consensus between taxa has been observed. The most well-studied of these processes are the self-incompatibility (SI) systems which act to recognise and reject self-pollen.

Pollinators provide essential services to crop and wild plants. Declines of native and managed pollinators have prompted considerable interest in the identity and importance of native pollinators and the services they provide. In agro-ecosystems there is particular concern over the impact of landscape simplification on these communities of 'service providers' , This thesis has two main aims; First, to investigate the ecosystem service of crop pollination by native insects, using ecological networks as a tool to identify pollinator interactions with crops, natural and semi-natural habitats. Pollination services to Fragaria x ananassa (strawberry), an insect-pollinated, high value crop, were used as a model system for this work. Networks were used to study interactions and spillover of insects between crop and semi-natural habitats at the local scale, the potential effects of poll in at or extinctions on pollination services, as well as pollen-transport interactions at the field scale and how they are affected by the structure of the surrounding landscape. The second aim of the thesis is {o explore the effects of sampling bias, specifically the type of sampling methodology employed, on the structure of the resulting plant-pollinator networks. The work presented in this thesis demonstrates the wide range of possible applications of plantpollinator networks to the study of crop pollination. The results reveal temporal changes in pollinator importance, spillover of pollinators across boundaries between crop and seminatural habitats and negative effects of landscape structure on pollinator communities and their interactions along with significant impacts of sampling bias on network structure. Network approaches to conservation issues reveal hidden effects of anthropogenic change on biodiversiry and are likely to be increasingly employed for such purposes in the future. The thesis ends by highlighting areas for improvement in the application of plant pollinator networks to the study of plant-pollinator community structure and pollination services, in order that ecologists gain the maximum benefit from using networks to answer questions about the effects of human activity on plant-pollinator communities and interactions.

This thesis addresses various aspects of the role of competition between European honeybees and wild pollinators on pollinator community structure and pollination services. In experimental studies in flight cages, the presence of foraging honeybees led to a decrease in visitation rate of bumblebees and increased their flower handling time. The travelling rime that bumblebees spent flying between flowers showed a positive relationship with number of honeybees per flower. In a field study, the proximity to a honeybee apiary significantly decreased the abundance of different groups of pollinators. Species richness and diversity of wild pol1inators also declined with proximity to the honeybee apiary, except for bumblebees. Pollination service significantly declined with the increase in distance from the apiary. In a field study assessing the development of experimental bumblebee colonies, those located near the honeybee apiary produced fewer queens and smaller queens and males. The offspring sex-ratio was significantly more male-biased in colonies closer to the apiary, which is less costly, but may result in lower fitness depending on the population sex ratio. Average colony weight near the apiary was lower in one of the two years. Finally, in an experimental study of plant pollination success, I found that pollinator performance (in terms of pollen transferring and their contribution to seed set) depended on the plant species, as bumblebees were more efficient on oilseed rape than honeybees and hoverflies while they did not differ from honeybees in terms of field bean pollination and seed set. Together these studies support the idea that honeybees interfere with foraging activity of wild pollinators. For bumblebees, the presence of high density of honeybees can negatively affect colony fitness. For the plant species that I studied, there were clear differences in the quality of visits for pollination between the species. However, this did not lead to lower seed set, because honeybee numbers overcompensated for the lower numbers of wild pollinators

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Thesis (M.Sc. Agric. (Crop Science)) --University of Limpopo, 2013 / The study aims to provide insights into the nature and extent of development funding provided to various poverty eradication projects by the National Development Agency (NDA) and its subsequent impact on reducing poverty in the predominantly rural communities of the Makhuduthamaga Municipality in the Limpopo Province. It examines in detail the impact made by the NDA on community development through the disbursement of funds to poverty eradication projects. It also provides insights into the total number of the NDA-funded projects and the total proportion of the NDA-funds allocated to them in the Makhuduthamaga Municipality. The study further examines the nature of the NDA support regarding the design of the interventions, relevance, participation of communities, delivery modalities and sustainability. The effectiveness of the NDA-funded projects in community development is determined using employment opportunities created, income generated, skills transferred, assets accumulated, sustainability mechanisms and community empowerment indicators. Although all of these indicators are found to be tightly linked to the NDA’s mandate of poverty eradication, the extent to which the NDA has achieved its objectives in disbursing development funding earmarked for poverty eradication and strengthening of CSOs was yet to be determined, hence the relevance of this study. The study, therefore, highlights key issues regarding the types of employment opportunities created and levels of income emanating from the NDA-funded projects. The study further highlights various areas of community empowerment, financial and sustainability measures put in place for the sustainability of the NDA-funded projects. Using a combined method of research, that is the qualitative and quantitative case study approach, the study highlights in detail insights into the impact made by the NDA on community development, particularly on Makhuduthamaga Municipality. The study highlights that while the NDA made some strides in the creation of employment opportunities, income generation, food security and community empowerment, both financial and institutional sustainability proved to be a daunting challenge for the NDA-funded projects Tailor-made and accredited training interventions coupled with the introduction of market-driven products to the NDA-funded projects as opposed to heavy reliance on donor funding will go a long way in bringing about productivity and, most probably, positive balance sheets and the maximum impact on the NDA funded projects.