Master of Science / Department of Entomology / Frank H. Arthur / Kun Yan Zhu / Experiments were conducted to assess the effects of direct and indirect exposure scenarios, different degrees of residual flour, open and obstructed positions, and seasonal temperature variations on the efficacy of synergized pyrethrin against the red flour beetle, Tribolium castaneum (Herbst) and the confused flour beetle, Tribolium confusum Jacquelin du Val. To evaluate effects of direct and indirect exposures of T. castaneum and T. confusum eggs, larvae, pupae, or eggs to the insecticide aerosol within a flour mill, the following treatments were made to each life stage: insects treated with aerosol and transferred to treated or untreated flour, untreated insects transferred to treated flour, and insects and flour combined and treated together. Different degrees of harborage or sanitation levels were created by exposing T. confusum larvae, pupae, and adults to pyrethrin aerosol in Petri dishes containing 0, 0.1, 1, 5, and 10 g of wheat flour. Effects of pyrethrin dispersal in open and obstructed positions and seasonal temperature variations were assessed by exposing T. confusum pupae and adults in open positions and inside wooden boxes (1 m long, 20 cm wide, and 5, 10, or 20 cm high) inside experimental sheds maintained at target temperatures of 22, 27, and 32 °C. Results showed that when T. castaneum and T. confusum were directly exposed to aerosol without the flour source, or with a low amount of flour at open exposed areas, the aerosol provided good control against all life stages of T. castaneum and T. confusum. However, when insects were indirectly exposed (treated together with flour or untreated insects were transferred to treated flour), or treated together with deeper flour amounts, and exposed inside the boxes, the efficacy was greatly reduced. Eggs and pupae of both the species were more susceptible compared to larvae and adults. Additionally, the moribund adults initially observed in indirect exposure treatments, or at the deeper flour depth and exposure positions insides the boxes, were better able to recover. Generally, temperatures in the range of 22-32 °C had no significant effects on overall efficacy of pyrethrin aerosol.

The purpose of this thesis is to substantiate the hypothetical development of a community radio station for a South African National Park, such as the Kruger National Park and to design the programming. As such the thesis has two phases namely a theoretical phase, where the variables and dynamics of the process of community unification, tourism’s ability to alleviate poverty and the central role played by radio are considered, and a creative phase, where the findings of the theoretical phase are applied in the design of the programme. The research leads to a model, and its methodology can be described as applied creative research. In order to arrive at the model, the research investigates a number of dynamics. In the first instance the research investigates a potential audience for such a community radio station. The notion of this potential audience or imagined community is interrogated. The thesis argues that there needs to be a conceptually synthesised audience, consisting of the local ethnic community, and a tourist community and that these two communities have interwoven functions around the provision and exploitation of tourism. Secondly, the thesis argues the demands of the audience synthesis, by investigating the nature of the South African tourism industry, with specific reference to the National Parks. In this section, the interrelatedness of the function and demands of the two communities are posited and developed, so that the groundwork for potential content of the Community Radio Station can be foregrounded. The thesis then interrogates the concept of communication by radio and draws on Marshall McLuhan’s concepts of ‘hot’ and ‘cold’ receivers and Walter Ong’s work around primary and secondary orality, amongst others. Here the thesis argues for the way that radio may be used to exploit and develop the synergy of the ethnic and the tourist community. The thesis then moves into the phase, where, through the recognised research process oftriangulation, which includes the synergised two communities (now a ‘Parks Emergent Radio Community’/ PERC), the shared content around the demands of tourism in National Parks, and the communal form of radio are creatively interwoven into a potential or hypothetical programme layout. The study concludes with a consideration of what might be the stumbling blocks in the way of implementing such a triangulated process and notes finances and budgets, training, and most specifically, bureaucratic intervention by licensing authorities as primary obstacles. The thesis argues for the advantages of the development of such a Community Radio Station for National Parks, given the projected steep increment in the tourist trade in South Africa. / Thesis (DPhil (Community Radio))--University of Pretoria, 2006. / Drama / unrestricted