• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5
  • Tagged with
  • 7
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

African leafy vegetables in South Africa

Jansen van Rensburg, WS, Vab Averbeke, W, Slabbert, R, Faber, M, Van Jaarsveld, P, Van Heerden, I, Wenhold, F, Oelofse, A 11 June 2007 (has links)
In this article the term ‘African leafy vegetables’ was adopted to refer to the collective of plant species which are used as leafy vegetables and which are referred to as morogo or imifino by African people in South Africa. Function is central in this indigenous concept, which is subject to spatial and temporal variability in terms of plant species that are included as a result of diversity in ecology, culinary repertoire and change over time. As a result, the concept embraces indigenous, indigenised and recently introduced leafy vegetable species but this article is concerned mainly with the indigenous and indigenised species. In South Africa, the collection of these two types of leafy vegetables from the wild, or from cultivated fields where some of them grow as weeds, has a long history that has been intimately linked to women and their traditional livelihood tasks. Among poor people in remote rural areas the use of these types of leafy vegetables is still common but nationwide there is evidence of decline, particularly in urban areas. Cultivation of indigenous or indigenised leafy vegetables is restricted to a narrow group of primarily indigenised species in South Africa. Seven groups of indigenous or indigenised African leafy vegetables that are important in South Africa were given special attention and their local nomenclature, ecology, use and cultivation are discussed.
2

Attitude towards the cultivation and utilisation of indigenous leafy vegetables in rural communities

Mungofa, Nyarai 12 1900 (has links)
Food insecurity remains a major challenge affecting the rural poor households in South Africa. The consumption of green leafy vegetables is important to address micronutrients deficiency in rural communities and, at the same time, it contributes to fibre intake. This study investigated the people’s attitude towards the cultivation and utilisation of ILVs in rural communities. A cross-section survey study was conducted among 1 000 respondents in randomly selected households in communities. The majority of respondents were not willingly consuming ILVs. This is because most consumers were black and of the low-income group. ILVs that are consumed grow mainly in the wild. The regular consumption of these vegetables as indicated in this study is interesting, as this will help in mitigating micronutrient deficiency. Furthermore, these vegetables could be incorporated in formulated food to improve iron and zinc, especially in infant foods formulation. Based on the findings of this study it would be important to find ways of encouraging cultivation of ILVs for both nutrition and as income generating activities. / Business Management / M. Consumer Science
3

The level of mycotic and mycotoxigenic Fusaria in traditional morogo and the agro-environment of Dikgale Demographic Surveillance Site (DDSS) / D.E. Mogakabe.

Mogakabe, Ditselatsela Elijah January 2007 (has links)
Ubiquitous in agro-environments, Fusarium species infect and damage economically important crops and contaminate food commodities with harmful secondary metabolites called mycotoxins. In addition, human infection by pathogenic Fusarium strains has now emerged as a major problem particularly among individuals with suppressed immunity. Trichothecenes, deoxynivalenol, nivalenol, rnoniliforme and fumonisins are potent toxins produced by Fusorium species including F. poae, F. nygami, F. oxysporum, F. proilferatum and F. verticillioides. The last three, together with F. solani and F. chlamydosporum are presently recognised as major role players in the occurrence of fusarioses in individuals with compromised immunity. In subsistence situations in rural areas of South Africa, a variety of traditional leafy vegetables, collectively known as morogo, supplement maize-based staple diets with minerals and vitamins. The utilisations of these traditional vegetables are generally based on indigenous knowledge pertaining to production and processing. Morogo plants are not natural hosts to mycotoxigenic and mycotic Fusarium species that are mainly associated with pathogeneses of grain crops such as maize. However, morogo growing in close proximity of maize in typical subsistence agricultural situations might be at risk of Fusarium contamination from maize. The study was conducted in the Dikgale Demographic Surveillance Site (DDSS), a rural area in the Limpopo Province characterised by the production of maize and different types of traditional morogo for household subsistence. HIVIAIDS is prevalent in the Limpopo Province. Chronic dietary exposure to Fusarium toxins and disseminated fusarioses might enhance disease outcomes associated with AIDS in affected individuals, thus adding to the burden of disease in DDSS communities. The aim of the study was to investigate the occurrence of mycotic and mycotoxigenic Fusarium species in traditional morogo and ago-environments in DDSS. Questionnaires were employed to obtain relevant information and indigenous knowledge from communities of Sefateng. Madiga, Mantheding and Moduane related to the utilisation of raditional morogo. At each village thepe (amaranth) and lerotho (African cabbage) were sampled on two occasions, namely before maize planting (M-) and when maize was fully grown (M+). Maize, soil and air were sampled at the same time. Botanical species identification was carried out on specimens of lerotho and thepe from each village. Lerotho. thepe, maize, soil and air samples were subjected to mycological analysis to determine the average fungal levels and Fusarium species that occurred. Samples of fresh and traditionally sun-dried samples of thepe and lerotho were analysed by HPLC for fumonisins. Average fungal plate counts of morogo from all four villages were notably higher in lerotho compared to thepe. Lerotho sampled from M- fields of Madiga, Mantheding and Moduane exhibited higher average fungal levels than those from the M+ fields. However, in lerotho sampled from the M+ field of Sefateng average fungal levels were significantly higher than that of the M- field. Fungal levels in maize growing close to morogo were lowest in Sefateng and highest in Moduane. The highest fungal counts in soil were reported for Sefateng's M- field and the lowest for Sefateng M+ field. Fungal levels were high in air samples of M+ fields of all four villages and the lowest in M- field of Sefateng. The majority Fusarium isolates retrieved from morogo and environmental samples belonged to known mycotoxigenic and/or mycotic species, though predominant species and levels thereof varied in samples from M- and M+ fields of the four villages. Fusarium levels in thepe from both M- and M+ fields were shown to be lower as in lerotho. In samples of the Sefateng M- field, F. poae occurred predominantly in lerotho, thepe, soil as well as air, while F. subglutinans was the predominant species in lerotho and air samples of Mantheding. In Sefateng samples from M+ field, F. chlamydosporum predominated among isolates retrieved from lerotho, F. prolifiratum and F. gramenearum among those from maize and F. solani among those from soil and air. F. proliferatum dominated among isolates from lerotho, maize, soil and air of M+ sites of Madiga and F. chlamydosporum in soil and air samples of Mantheding. HPLC analysis detected fumonisin B1 in traditionally sun-dried as well as fresh samples of lerorho as well as thepe. The occurrence of mycotoxigenic and rnycotic Fusarium species in traditional morogo and agro-environments might be an aggravating health risk factor for DDSS communities. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
4

The level of mycotic and mycotoxigenic Fusaria in traditional morogo and the agro-environment of Dikgale Demographic Surveillance Site (DDSS) / D.E. Mogakabe.

Mogakabe, Ditselatsela Elijah January 2007 (has links)
Ubiquitous in agro-environments, Fusarium species infect and damage economically important crops and contaminate food commodities with harmful secondary metabolites called mycotoxins. In addition, human infection by pathogenic Fusarium strains has now emerged as a major problem particularly among individuals with suppressed immunity. Trichothecenes, deoxynivalenol, nivalenol, rnoniliforme and fumonisins are potent toxins produced by Fusorium species including F. poae, F. nygami, F. oxysporum, F. proilferatum and F. verticillioides. The last three, together with F. solani and F. chlamydosporum are presently recognised as major role players in the occurrence of fusarioses in individuals with compromised immunity. In subsistence situations in rural areas of South Africa, a variety of traditional leafy vegetables, collectively known as morogo, supplement maize-based staple diets with minerals and vitamins. The utilisations of these traditional vegetables are generally based on indigenous knowledge pertaining to production and processing. Morogo plants are not natural hosts to mycotoxigenic and mycotic Fusarium species that are mainly associated with pathogeneses of grain crops such as maize. However, morogo growing in close proximity of maize in typical subsistence agricultural situations might be at risk of Fusarium contamination from maize. The study was conducted in the Dikgale Demographic Surveillance Site (DDSS), a rural area in the Limpopo Province characterised by the production of maize and different types of traditional morogo for household subsistence. HIVIAIDS is prevalent in the Limpopo Province. Chronic dietary exposure to Fusarium toxins and disseminated fusarioses might enhance disease outcomes associated with AIDS in affected individuals, thus adding to the burden of disease in DDSS communities. The aim of the study was to investigate the occurrence of mycotic and mycotoxigenic Fusarium species in traditional morogo and ago-environments in DDSS. Questionnaires were employed to obtain relevant information and indigenous knowledge from communities of Sefateng. Madiga, Mantheding and Moduane related to the utilisation of raditional morogo. At each village thepe (amaranth) and lerotho (African cabbage) were sampled on two occasions, namely before maize planting (M-) and when maize was fully grown (M+). Maize, soil and air were sampled at the same time. Botanical species identification was carried out on specimens of lerotho and thepe from each village. Lerotho. thepe, maize, soil and air samples were subjected to mycological analysis to determine the average fungal levels and Fusarium species that occurred. Samples of fresh and traditionally sun-dried samples of thepe and lerotho were analysed by HPLC for fumonisins. Average fungal plate counts of morogo from all four villages were notably higher in lerotho compared to thepe. Lerotho sampled from M- fields of Madiga, Mantheding and Moduane exhibited higher average fungal levels than those from the M+ fields. However, in lerotho sampled from the M+ field of Sefateng average fungal levels were significantly higher than that of the M- field. Fungal levels in maize growing close to morogo were lowest in Sefateng and highest in Moduane. The highest fungal counts in soil were reported for Sefateng's M- field and the lowest for Sefateng M+ field. Fungal levels were high in air samples of M+ fields of all four villages and the lowest in M- field of Sefateng. The majority Fusarium isolates retrieved from morogo and environmental samples belonged to known mycotoxigenic and/or mycotic species, though predominant species and levels thereof varied in samples from M- and M+ fields of the four villages. Fusarium levels in thepe from both M- and M+ fields were shown to be lower as in lerotho. In samples of the Sefateng M- field, F. poae occurred predominantly in lerotho, thepe, soil as well as air, while F. subglutinans was the predominant species in lerotho and air samples of Mantheding. In Sefateng samples from M+ field, F. chlamydosporum predominated among isolates retrieved from lerotho, F. prolifiratum and F. gramenearum among those from maize and F. solani among those from soil and air. F. proliferatum dominated among isolates from lerotho, maize, soil and air of M+ sites of Madiga and F. chlamydosporum in soil and air samples of Mantheding. HPLC analysis detected fumonisin B1 in traditionally sun-dried as well as fresh samples of lerorho as well as thepe. The occurrence of mycotoxigenic and rnycotic Fusarium species in traditional morogo and agro-environments might be an aggravating health risk factor for DDSS communities. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
5

The role of indigenously-associated abuscular mycorrhizal fungi as biofertilisers and biological disease-control agents in subsistence cultivation of morogo / Mohlapa Junior Sekoele

Sekoele, Mohlapa Junior January 2006 (has links)
The study examined interactions between morogo plants, arbuscular mycorrhizal fungi (AMF) and Fusarium species. Morogo refers to traditional leafy vegetables that, together with maize porridge, are dominant staple foods in rural areas of the Limpopo Province such as the Dikgale Demographic Surveillance Site (DDSS). Morogo plants grow either as weeds (often among maize), occur naturally in the field or are cultivated as subsistence crops by rural communities. Botanical species of morogo plants consumed in the DDSS were determined. Colonisation of morogo plant roots by AMF and Fusarium species composition in the immediate soil environment were investigated in four of eight DDSS subsistence communities, Isolated AMF were shown to belong to the genera Acaulospora and Glomus. Twelve Fusarium species were isolated from soil among which Fusariurn verticilliodes and Fusarium proliferaturn occurred predominantly. Greenhouse pot trials were conducted to examine the effect of AMF on morogo plant growth (cowpea; Mgna unguiculata) and Fusarium proliferatum levels in soil, Interaction between plants and AMF, as well as tripartite interactions of cowpea plants, AMF and Fusarium proliferatum were investigated. Non-inoculated cowpea plants served as controls for the following inoculations of cowpea in pots: (i) Fusarium proliferatum; (ii) commercial AMF from Mycoroot (PTY) Ltd. (a mixture of selected indigenous Glomus spp referred to commercial AMF for the purpose of this study); (iii) indigenous AMF obtained from DDSS soil (referred to iocal AMF for the purpose of this study); (iv) commercial AMF plus Fusarium proliferatum; (v) local AMF plus Fusariurn proliferatum. Results showed reduced root colonization by local as well as commercial AMF when Fusarium proliferatum were present. Local AMF significantly enhanced cowpea growth while commercial AMF apparently reduced the level of Fusarium proliferatum in the rhizosphere and surrounding soil. Results suggest that AMF may have potential as biological growth enhancers and bioprotective agents against Fusarium proliferatum. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
6

The role of indigenously-associated abuscular mycorrhizal fungi as biofertilisers and biological disease-control agents in subsistence cultivation of morogo / Mohlapa Junior Sekoele

Sekoele, Mohlapa Junior January 2006 (has links)
The study examined interactions between morogo plants, arbuscular mycorrhizal fungi (AMF) and Fusarium species. Morogo refers to traditional leafy vegetables that, together with maize porridge, are dominant staple foods in rural areas of the Limpopo Province such as the Dikgale Demographic Surveillance Site (DDSS). Morogo plants grow either as weeds (often among maize), occur naturally in the field or are cultivated as subsistence crops by rural communities. Botanical species of morogo plants consumed in the DDSS were determined. Colonisation of morogo plant roots by AMF and Fusarium species composition in the immediate soil environment were investigated in four of eight DDSS subsistence communities, Isolated AMF were shown to belong to the genera Acaulospora and Glomus. Twelve Fusarium species were isolated from soil among which Fusariurn verticilliodes and Fusarium proliferaturn occurred predominantly. Greenhouse pot trials were conducted to examine the effect of AMF on morogo plant growth (cowpea; Mgna unguiculata) and Fusarium proliferatum levels in soil, Interaction between plants and AMF, as well as tripartite interactions of cowpea plants, AMF and Fusarium proliferatum were investigated. Non-inoculated cowpea plants served as controls for the following inoculations of cowpea in pots: (i) Fusarium proliferatum; (ii) commercial AMF from Mycoroot (PTY) Ltd. (a mixture of selected indigenous Glomus spp referred to commercial AMF for the purpose of this study); (iii) indigenous AMF obtained from DDSS soil (referred to iocal AMF for the purpose of this study); (iv) commercial AMF plus Fusarium proliferatum; (v) local AMF plus Fusariurn proliferatum. Results showed reduced root colonization by local as well as commercial AMF when Fusarium proliferatum were present. Local AMF significantly enhanced cowpea growth while commercial AMF apparently reduced the level of Fusarium proliferatum in the rhizosphere and surrounding soil. Results suggest that AMF may have potential as biological growth enhancers and bioprotective agents against Fusarium proliferatum. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
7

Attitude towards the cultivation and utilisation of indigenous leafy vegetables in rural communities

Mungofa, Nyarai 12 1900 (has links)
Food insecurity remains a major challenge affecting the rural poor households in South Africa. The consumption of green leafy vegetables is important to address micronutrients deficiency in rural communities and, at the same time, it contributes to fibre intake. This study investigated the people’s attitude towards the cultivation and utilisation of ILVs in rural communities. A cross-section survey study was conducted among 1 000 respondents in randomly selected households in communities. The majority of respondents were not willingly consuming ILVs. This is because most consumers were black and of the low-income group. ILVs that are consumed grow mainly in the wild. The regular consumption of these vegetables as indicated in this study is interesting, as this will help in mitigating micronutrient deficiency. Furthermore, these vegetables could be incorporated in formulated food to improve iron and zinc, especially in infant foods formulation. Based on the findings of this study it would be important to find ways of encouraging cultivation of ILVs for both nutrition and as income generating activities. / Life and Consumer Science / M.CS.

Page generated in 0.0352 seconds