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M. Tech. (Biotechnology, Department of Biosciences, Faculty of Applied and Computer Sciences) Vaal University of Technology / Sweetpotato is one of the most important food crops in developing countries including South Africa. Currently two major types of cultivars are grown in South Africa: one is the orange-fleshed sweetpotato (OFSP) which has high β-carotene content, a precursor of vitamin A. The second type is the cream-fleshed sweetpotato (CFSP) which has low β-carotene content but is high in dry matter. Most South Africans prefer the CFSP although the OFSP offers more advantages. This presents a challenge to plant breeders to develop new varieties that will combine the desirable qualities of both the cultivars. To achieve this goal, plant breeders need knowledge about the genetic variation of the crop to develop an efficient breeding programme. This study assessed the genetic relationships of 28 orange- and cream-fleshed sweetpotato accessions by (i) examining the variation in leaf proteins, (ii) using random amplified polymorphic DNA (RAPD) and, (iii) using variation of the ITS region. The analysis of proteins, RAPD and variation of the ITS region polymorphism levels were 55.6%, 98% and 16.5%, respectively. Dendrograms generated from all the analyses generally clustered the accession according to their flesh colour and country of origin. Analysis of molecular variance (AMOVA) found a significant difference between OFSP and CFSP and a significant difference between the South African and non-South African germplasm. The high genetic diversity in the South African sweetpotato germplasm is a positive indicator for a breeding programme that has a number of targets such as breeding for nutritional improvement, disease resistance and drought tolerance / Hub and Spokes and National Research Foundation (NRF)

Thesis (MSc)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.

>Magister Scientiae - MSc / In this study, the diversity of endophytic bacteria associated with food crops, sorghum (Sorghum bicolor L. Moench), pearl millet (Pennisetum glaucum L.) and groundnut (Arachis villosulicarpa) is investigated using culture-independent techniques: terminal retriction fragment length polymorphism (t- RFLP) and next generation sequencing (NGS). The first objective of this study was to investigate the effect of different DNA extraction protocols on mDNA yield and quality, as well as the diversity of endophytic bacteria retrieved from root and stem tissues (0.1g or 0.3g) of sorghum, pearl millet and groundnut. Protocols used include two classical methods (CTAB- and SDS-based) and five commercial kits: MoBio PowerPlant Pro® DNA Isolation Kit, Qiagen DNeasyR Plant Mini Kit, Fermentas GeneJET Plant Genomic DNA Purification Kit, MoBio PowerSoilTM DNA Purification Kit and MoBio UltraClean® Soil DNA Isolation Kit. Eletrophoresis and the Nanodrop were used to determine DNA yield and purity

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In the 1990s social scientists researching public perceptions of GM foods recommended the introduction of new modes of public participation to make decision-making more inclusive. This research utilises categories and concepts from cultural theory (as developed by anthropologists Mary Douglas, Michael Thompson and Steve Rayner, and political scientists Aaron Wildavsky and Richard Ellis) as tools to consider how a range of opinions, illustrated by cultural theory's ideal types, were represented within the GM crop debate. By doing so, it considers whether this approach supports the notion that greater public participation would improve inclusiveness. Furthermore, it considers how best to model the ways that individuals utilised the discourse of cultural theory's ideal types, and whether this has implications for seeking greater inclusiveness. The research is based upon 55 one-to-one interviews that were conducted with various individuals engaged in the GM crop debate in 2000, and secondary sources of data such as media coverage, electronic mailing lists and public meetings between 1996 and 2002. It was determined that the discourses of cultural theory's ideal types were best presented along a continuum, with the hierarchists in the centre and the egalitarians and individualists at either extreme. Within the wider public debate, the media and public reflected the concerns of egalitarians, while government discourse reflected the concerns of hicrarchists. By enabling the public to have a greater say in decision-making,it is asserted that decisions will favour the egalitarian outlook and will ignore the wisdom of cultural theory's other ideal types. Furthermore, since the discourse of those engaged in the debate included all but the most fatalistic comments made by members of the public, it is argued that public participation is unlikely to bring any new voices to the debate. Rather than introducing new modes of public participation,t his research recommends that the government actively consults with individuals already engaged in the GM crop debate on all issues, including those of a more political nature. The aim of such an exercise would be to identify, communicate and consider the full range of opinions available so that decisions can become more fully informed, transparent and trusted.

This research is concerned with exploring differences in the meaning of entrepreneurial behaviour among owner-managers of agricultural enterprises in Bulgaria. It aims to gain a better understanding of the origin and development of small businesses in a postsocialist context. Entrepreneurial behaviour is understood as the start-up and development of a new business and is examined through the views and experiences of agricultural producers. An exploratory conceptual framework, encompassing the individual owner-manger, the enterprise and the family, is developed to guide the investigation. It facilitated an analysis of the entrepreneurial process and the relationship between agricultural producers and their enterprises, while also taking into account the possible influences of involved family members. Data were drawn from qualitative face-to-face interviews with a diverse sample of 83 agricultural producers in four rural settlements. The respondents represented different demographic characteristics and agricultural sub-sectors. The findings from this exploratory research provide useful insights into the entrepreneurial behaviour of Bulgarian agricultural producers. Different patterns of engagement with the agricultural enterprises emerge. These are explained through startup motivations and growth aspirations and achievement, which in turn are related to differences in the scale of enterprises. Furthermore, patterns of engagement are related to differences in orientation towards self-employment and adoption of the role of owner-manager. Start-up motivations are associated with a complex interaction of different factors. They are also strongly related to the post-socialist context as represented by macro-level changes. The interviewees recognised and reacted differently to these changes. Presence of involved family members could have either a positive or negative influence on the start-up of new additional activities or the enlargement of existing ones. Contextual issues like the post-socialist background, culture and family contributed to a better understanding of the businesses and entrepreneurial behaviour. The results suggest that the entrepreneurial behaviour of post-socialist agricultural producers requires further research in order to gain an indepth understanding of why they undertake their own business.

Rapid transformation in the food retail supply system, accompanied by rational economic efficiency, has marginalized the role that traditional markets play in the UK food distribution system. Yet these markets survive, some even thrive, implying that traditional food markets cannot be defined simply in terms of their distribution function. Traditional food markets are part of the surrounding food retail environment and whether they survive or thrive is dependent on wider economic and societal dynamics and change. This thesis links the micro-level activities of traditional food market exchange with how food systems, power structures and consumption practices interact and transform each other over time and space at the macro-level. The research provides the first detailed assessment of traditional food markets in England and examines their contemporary role in fresh food provisioning. The thesis proposes a cultural economy framework that examines how food retail restructuring and changing patterns of fresh food consumption have affected the internal and external spaces and places that support the everyday economic processes and cultural practices of traditional food market exchange. The research employs a mixed methods approach with three inter-related phases. First, the construction of a database of UK food markets identified 1,124 traditional food markets operating in the UK and the empirical analysis, using geo-coded data and more detailed location quotient (LQ) analysis, mapped the geographies and concentrations of traditional food markets and their links with wholesale markets and farmers' markets. Second, data drawn from an email questionnaire survey with traditional food market managers examined the effects of retail restructuring and changing fresh food shopping habits on these markets. In the third and final phase, detailed analysis from case study research in two contrasting traditional food markets, in the North East and Eastern regions of England, examined how the market as place significantly shapes the distributive processes and practices of buying and selling that transform fresh food into the `market product', and also explored the reciprocal relations between the economic and the cultural and between value(s) and exchange. The research findings provide new insights into the traditional food retail sector. The database and email survey analysis reveal how market geographies have been affected by regulatory, economic and cultural change and demonstrate how market and place are entwined in a relationship that has adapted to retail restructuring and changes in fresh food provisioning. Detailed case study analysis reveals how traditional markets are intimately linked with the regions and cities where they are located and how different geographies, histories and approaches to food and farming have moulded the relationship between market and fresh food over time. Although the overall economic value of fresh food sold on traditional markets is reduced in real terms, its symbolic value as `the market product' is not. Historically and culturally, the traditional market may be considered part of a `traditional' food system that aimed to provide fresh and affordable food to all, but the contemporary market is a different place. The findings reveal a marketplace frequently articulated through parallel fresh food trading and shopping experiences at the supermarket and the farmers' market and informed by practical and local knowledge systems. Knowledge systems help define food-provisioning expertise in the traditional food system and the value put on fresh produce depends on both economic and less tangible factors bound up with cultural and moral understandings. How fresh food is assigned monetary, social and symbolic value by market actors' everyday practices demonstrates a `sliding scale' of moral and monetised values as fresh food takes on cultural form The value(s) assigned to fresh food traded on the market fundamentally shape how it performs in the contemporary context and ultimately determine whether its role in fresh food provisioning declines, survives or thrives.

Thesis (M.Sc. (Microbiology)) -- University of Limpopo, 2010 / A 29 kDa lectin that shows specificity for galactose was isolated from Lonchocarpus capassa seeds by a combination of ammonium sulphate precipitation and affinity chromatography on a galactose-sepharose column. The 29 kDa lectin subunit co-purified with a 45 kDa subunit. The N-terminal sequence of the 29 kDa subunit showed homology to other legume lectins while that of 45 kDa subunit was capped. A 360 bp fragment was amplified using degenerate primers designed from internal protein sequences of the 29 kDa subunit and a 5´ RACE system primer. The cDNA fragment was cloned into pTz57R/Tvector and transformed into E. coli. The partial amino acid sequence of the lectin subunit was deduced from the nucleotide sequence of the clone. The 360 bp fragment consisted of 342 bp sequence coding for the start codon, leader sequence, N-Terminal sequence and sequences of the 79 amino acids from N-terminus. Comparison of the deduced amino acid sequence with other legume lectins showed regions of sequence homology with precursor sequences of Robinia pseudoacacia Bark lectin, a non seed lectin from Pisum sativum (pea), and the galactose specific peanut agglutinin (PNA) from Arachis hypogaea. Alignment of these sequences showed conserved regions including the metal binding sites found in all legume lectins. The 5´ end DNA sequence was used to design locus-specific primers which were used with genome walking cassette primers in an attempt to amplify the full L. capassa lectin gene. The cassette primers were designed from restriction enzyme sites on the cassette. Of all the restriction enzymes on the cassette Hind III and the L. capassa gene-specific primers amplified 288 bp of the 342 bp sequence already obtained from sequencing of the cDNA sequence with minor amino acid differences. Although the full lectin sequence was not obtained the study confirmed the presence of a galactose-specific lectin in L. capassa seeds.

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