Business cycle synchronization in SACU countries: a wavelet coherence analysis
- Authors: Khoza, Sithobile X
- Date: 2022-12
- Subjects: Economic cycles , Synchronization -- (SACU) Countries
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/60221 , vital:63844
- Description: The discussion on the viability of the Southern African Customs Union (SACU) as a monetary union has been ongoing for years. SACU is the oldest Customs Union in history, formed in 1910. Employing the Optimum Currency Areas (OCA) theory, the study examined SACU’s readiness for a single currency. There are several technical requirements needed to form an OCA, however, one of the most vital of these with regards to a country’s suitability to enter a currency union is Business Cycle Synchronization. Therefore, SACU’s readiness was tested by establishing Business Cycle synchronization between the 5 member states. Although Business Cycles Synchronization have not been proven, SACU countries have moved towards a complete monetary union because of increasing macroeconomic convergence. Our study using Wavelet analysis sets out to establish if there is a synchronization of Business cycles with SACU members. Cyclical components were isolated, from the real GDP growth rate of each country from 1981 to 2020, using the Hodrick-Prescott filter (HP), Band-Pass filter (BP), and the Christiano-Fitzgerald Filter (CF). In the 2 by 2 analysis, our wavelet coherence showed that SACU countries are synchronized with each other, while South Africa displayed its dominance in the union by showing significant synchronization with all the members of the union both in the short and long run. The Vector wavelet analysis results concluded that, as a group, SACU shows much higher degrees of synchronization. The group synchronization is statistically significant throughout the period of study. Furthermore, there is an indication of consistent synchronization, in the long and short run. Overall, the results of our study conclude that there is synchronization in the SACU countries. Therefore, SACU counties can form an OCA as they meet the desirably requirements. , Thesis (MCom) -- Faculty of Business and Economic Sciences, 2022
- Full Text:
- Date Issued: 2022-12
- Authors: Khoza, Sithobile X
- Date: 2022-12
- Subjects: Economic cycles , Synchronization -- (SACU) Countries
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/60221 , vital:63844
- Description: The discussion on the viability of the Southern African Customs Union (SACU) as a monetary union has been ongoing for years. SACU is the oldest Customs Union in history, formed in 1910. Employing the Optimum Currency Areas (OCA) theory, the study examined SACU’s readiness for a single currency. There are several technical requirements needed to form an OCA, however, one of the most vital of these with regards to a country’s suitability to enter a currency union is Business Cycle Synchronization. Therefore, SACU’s readiness was tested by establishing Business Cycle synchronization between the 5 member states. Although Business Cycles Synchronization have not been proven, SACU countries have moved towards a complete monetary union because of increasing macroeconomic convergence. Our study using Wavelet analysis sets out to establish if there is a synchronization of Business cycles with SACU members. Cyclical components were isolated, from the real GDP growth rate of each country from 1981 to 2020, using the Hodrick-Prescott filter (HP), Band-Pass filter (BP), and the Christiano-Fitzgerald Filter (CF). In the 2 by 2 analysis, our wavelet coherence showed that SACU countries are synchronized with each other, while South Africa displayed its dominance in the union by showing significant synchronization with all the members of the union both in the short and long run. The Vector wavelet analysis results concluded that, as a group, SACU shows much higher degrees of synchronization. The group synchronization is statistically significant throughout the period of study. Furthermore, there is an indication of consistent synchronization, in the long and short run. Overall, the results of our study conclude that there is synchronization in the SACU countries. Therefore, SACU counties can form an OCA as they meet the desirably requirements. , Thesis (MCom) -- Faculty of Business and Economic Sciences, 2022
- Full Text:
- Date Issued: 2022-12
Lateral and vertical mineral-chemical variation in high-grade ores of the Kalahari Manganese Field, and implications for ore genesis and geometallurgy
- Authors: Motilaodi, Donald
- Date: 2022-10-14
- Subjects: Manganese ores , Geometallurgy , Hydrothermal alteration , Petrology , Mineralogy , Geochemistry
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362972 , vital:65379
- Description: The Kalahari Manganese Field (KMF) is a world-class resource of manganese ore hosted by the Paleoproterozoic Hotazel banded iron formation. KMF ores are categorised into two main types, i.e., low-grade, carbonate rich, braunitic ore (Mn≤40wt%) and carbonate-free, high-grade, Ca-braunite+hausmannite ore (Mn≥44wt%). High-grade ores, also known as Wessels type from the homonymous mine in the northernmost KMF, are thought to have formed from variable degrees of hydrothermal carbonate and silica leaching from a low-grade ore precursor, termed Mamatwan-type after the homonymous mine in the southernmost KMF. This project aims to conduct a mineralogical and mineral-chemical study of representative manganese ore samples from a suite of drillcores intersecting both the upper and the lower layers in the northern KMF, covering the areas of Wessels, N’chwaning and Gloria mines. Petrographically, the high-grade Mn ore displays great variability in three-dimensional space. Texturally, the ores exhibit a great variety of textures which may or may not show preservation of the laminated and ovoidal textures that typify the postulated low-grade protore. There is also significant variation in the mineralogical and geochemical characteristics of the high-grade Mn ores both vertically and laterally. Vertical variation includes, probably for the first time, variability between the upper and lower ore layers within individual drillcores of the Hotazel sequence. Mineralogically, the ores contain variable modal abundances of the ore-forming minerals braunite (I, II, “new”) and hausmannite, and much less so of bixbyite, marokite and manganite. Common accessories include andradite, barite and low-Mn carbonate minerals. Chemically, the dominant ore minerals braunite and hausmannite, contain Fe up to 22 and 15wt% respectively, which accounts for the bulk of the iron contained in the ores. Braunite compositions also exhibit a large range with respect to their ratio of Ca/Si. Mineral-specific trace element concentrations for the same minerals measured by LA-ICP-MS, reveal generally large variations from one element to the other. When normalized against the trace element composition of bulk low-grade precursor ore, strong enrichments are recorded for both hausmannite and braunite in selected alkali/alkali earth elements, transition metals and lanthanides, such as Sc, Co, Zn, Cu, Pb, La, and Ce. These are akin to enrichments recorded in average high-grade ore. Although there is also no obvious relationship between Fe content in both hausmannite and braunite and their trace element abundances, the drillcore that captures high-grade ore with the highest trace element concentrations appears to be located most proximal to a major fault. Results collectively suggest that high-grade Mn ores of the KMF have undergone a complex hydrothermal history with a clear and significant metasomatic addition of trace elements into ore-forming minerals. First order trends in the mineralogical and mineral-chemical distribution of the ores in space, suggest hausmannite-dominated ores near the Hotazel suboutcrop, and an apparent decline in ore quality with braunite II-andradite-barite-calcite ores as the major graben fault is approached in a southwesterly direction. The latter trend appears to be at odds with prevailing fault-controlled alteration models. Elucidating that hydrothermal history of the Wessels-type high grade Mn ores of the KMF, will be crucial to understanding the compositional controls of these ores in space, and the potential impact thereof in terms of geometallurgy. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Motilaodi, Donald
- Date: 2022-10-14
- Subjects: Manganese ores , Geometallurgy , Hydrothermal alteration , Petrology , Mineralogy , Geochemistry
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362972 , vital:65379
- Description: The Kalahari Manganese Field (KMF) is a world-class resource of manganese ore hosted by the Paleoproterozoic Hotazel banded iron formation. KMF ores are categorised into two main types, i.e., low-grade, carbonate rich, braunitic ore (Mn≤40wt%) and carbonate-free, high-grade, Ca-braunite+hausmannite ore (Mn≥44wt%). High-grade ores, also known as Wessels type from the homonymous mine in the northernmost KMF, are thought to have formed from variable degrees of hydrothermal carbonate and silica leaching from a low-grade ore precursor, termed Mamatwan-type after the homonymous mine in the southernmost KMF. This project aims to conduct a mineralogical and mineral-chemical study of representative manganese ore samples from a suite of drillcores intersecting both the upper and the lower layers in the northern KMF, covering the areas of Wessels, N’chwaning and Gloria mines. Petrographically, the high-grade Mn ore displays great variability in three-dimensional space. Texturally, the ores exhibit a great variety of textures which may or may not show preservation of the laminated and ovoidal textures that typify the postulated low-grade protore. There is also significant variation in the mineralogical and geochemical characteristics of the high-grade Mn ores both vertically and laterally. Vertical variation includes, probably for the first time, variability between the upper and lower ore layers within individual drillcores of the Hotazel sequence. Mineralogically, the ores contain variable modal abundances of the ore-forming minerals braunite (I, II, “new”) and hausmannite, and much less so of bixbyite, marokite and manganite. Common accessories include andradite, barite and low-Mn carbonate minerals. Chemically, the dominant ore minerals braunite and hausmannite, contain Fe up to 22 and 15wt% respectively, which accounts for the bulk of the iron contained in the ores. Braunite compositions also exhibit a large range with respect to their ratio of Ca/Si. Mineral-specific trace element concentrations for the same minerals measured by LA-ICP-MS, reveal generally large variations from one element to the other. When normalized against the trace element composition of bulk low-grade precursor ore, strong enrichments are recorded for both hausmannite and braunite in selected alkali/alkali earth elements, transition metals and lanthanides, such as Sc, Co, Zn, Cu, Pb, La, and Ce. These are akin to enrichments recorded in average high-grade ore. Although there is also no obvious relationship between Fe content in both hausmannite and braunite and their trace element abundances, the drillcore that captures high-grade ore with the highest trace element concentrations appears to be located most proximal to a major fault. Results collectively suggest that high-grade Mn ores of the KMF have undergone a complex hydrothermal history with a clear and significant metasomatic addition of trace elements into ore-forming minerals. First order trends in the mineralogical and mineral-chemical distribution of the ores in space, suggest hausmannite-dominated ores near the Hotazel suboutcrop, and an apparent decline in ore quality with braunite II-andradite-barite-calcite ores as the major graben fault is approached in a southwesterly direction. The latter trend appears to be at odds with prevailing fault-controlled alteration models. Elucidating that hydrothermal history of the Wessels-type high grade Mn ores of the KMF, will be crucial to understanding the compositional controls of these ores in space, and the potential impact thereof in terms of geometallurgy. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
African feminism(s) as it informs the experiences of African women leaders at universities in South Africa
- Authors: Tau, Siphokazi
- Date: 2022-04
- Subjects: Feminisms--Africa , Leadership in women , Higher education -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59991 , vital:62731
- Description: The South African higher education geography is one that is met with contesting ideas. The establishment of the university in Africa was a project to mimic the exclusionary nature of the western university. Of centering a particular knowledge and way of being, leaving African women and other marginalised groups outside of the culture of the space and away from the possibility of being knowledge producers. The end of Apartheid, signaled an opportunity for new policies that address racial, gendered and various other lines of oppression and marginalisation. Universities, Technical and Vocational Education and Training (TVET) colleges with different histories were merged to make way for the new South Africa. Access to institutions of higher education opened up across geographies, making way for a multicultural student and staff demographic. This transformation has also led to the transformation of the leadership structures of such spaces, with currently only five institutions being led by female and women, out of twenty-six in the country. The aim of this study is to understand the experiences of African women who are leaders in universities, focusing on how they negotiate a history of being excluded in the space with the present context of being able to influence the future of higher education. Using an African feminist lens, I draw on five individual interviews and secondary data from previous studies to excavate phenomenological experiences. The findings reveal that feminist traits of equality of social justice are integral in how the participants perform their leadership. The findings also show experiences of belonging in the culture of the university cause a great deal of tension of which the leaders are constantly working to change, to establish different cultures of being and existing in the South African university. , Thesis (MA) -- Faculty of Humanities, School of governmental science and social sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Tau, Siphokazi
- Date: 2022-04
- Subjects: Feminisms--Africa , Leadership in women , Higher education -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59991 , vital:62731
- Description: The South African higher education geography is one that is met with contesting ideas. The establishment of the university in Africa was a project to mimic the exclusionary nature of the western university. Of centering a particular knowledge and way of being, leaving African women and other marginalised groups outside of the culture of the space and away from the possibility of being knowledge producers. The end of Apartheid, signaled an opportunity for new policies that address racial, gendered and various other lines of oppression and marginalisation. Universities, Technical and Vocational Education and Training (TVET) colleges with different histories were merged to make way for the new South Africa. Access to institutions of higher education opened up across geographies, making way for a multicultural student and staff demographic. This transformation has also led to the transformation of the leadership structures of such spaces, with currently only five institutions being led by female and women, out of twenty-six in the country. The aim of this study is to understand the experiences of African women who are leaders in universities, focusing on how they negotiate a history of being excluded in the space with the present context of being able to influence the future of higher education. Using an African feminist lens, I draw on five individual interviews and secondary data from previous studies to excavate phenomenological experiences. The findings reveal that feminist traits of equality of social justice are integral in how the participants perform their leadership. The findings also show experiences of belonging in the culture of the university cause a great deal of tension of which the leaders are constantly working to change, to establish different cultures of being and existing in the South African university. , Thesis (MA) -- Faculty of Humanities, School of governmental science and social sciences, 2022
- Full Text:
- Date Issued: 2022-04
Hydraulic vulnerability of Subtropical Thicket to drought : a remote sensing and physiological perspective
- Authors: Buttner, Daniel Harry
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55455 , vital:52017
- Description: Water availability is one of largest constraints on plant survival, growth, and species distribution globally. The recent escalation in tree mortality coupled with declining precipitation and amplified temperatures has implicated drought as a major cause behind many large-scale dieback events observed across the world. Raising the question, what makes some species more resistant and persist while others dwindle and vanish from the landscape? The observed variability in species drought susceptibility demonstrates the complexity of physiological responses of plants to changes in water availability. Hydraulic dysfunction in plants has been purported to be the key mechanism behind drought-induced mortality provoking interest in hydraulic traits and critical thresholds of xylem physiological function. The capability of species to maintain hydraulic functionality under drought strongly influences the survival and general productivity towards water deficits. Hence, two core objectives, and subsequently aims, of this thesis are firstly to investigate the effect of drought on Subtropical Thicket vegetation health and productivity, and secondly to examine the underpinning physiological mechanisms and functional thresholds relaying speciesspecific drought vulnerability within this semi-arid biome. In first data chapter, this thesis offers an assessment of vegetation change under drought and its influence on plant physiological function and productivity across a subsection of Subtropical Thicket distribution. Additionally, this chapter provides a regional scale perspective of drought on Subtropical Thicket flora in the Eastern Cape of South Africa. A severe anomalous dieback event, which coincided with extreme, accumulative drought conditions was observed in 2020. Employing a combination of field-based approaches and remote sensing, this chapter aimed to provide a comprehensive report of the extent and severity of crown defoliation and canopy dieback following this event, additionally describing predisposing and compounding factors. Based on Standardized Precipitation Evapotranspiration and Standardized Precipitation Indices this event began in 2015 and coincided with amplified temperatures, exacerbating evaporative demand. Aerial UAV surveys and field-based investigations were undertaken. Remotely sensed (RS) indices provided an avenue for extensive spatiotemporal investigations to uncover the extent of drought-related impact on vegetation productivity and discuss potential underpinning mechanisms behind drought-induced mortality in Subtropical Thicket. Leveraging long-term time series RS data, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), from Moderate Resolution Imaging Spectroradiometer (MODIS) satellites as a proxy vegetation physiological status in combination with SPI and SPEI describing drought condition and groundbased surveying defining canopy vitality condition this study incidentally addressed the aim of endeavoring to link drought-induced mortality and early warning symptoms observed in the field with RS time series data to describe drought impacts across Subtropical Thicket. Furthermore, the findings of this chapter demonstrate the spatial and temporal heterogeneity in drought impacts on Subtropical Thicket. The recent drought of 2015 till 2021 is the longest documented period for the past 50 years in which there has been no accumulated net positive water availability, this apparently perpetual state of water deficiency has enacted a high cost for vegetation productivity and growth for the study area, exhibited well by average NDVI values of less than -0.5 for over 70% of the research site. The findings of this chapter report, to the contrary of anecdotal suggestions in the literature, on the intrinsic tolerance of Subtropical Thicket and that ii drought has a far more significant role on overall vegetation productivity, growth, and mortality in this region. The second data chapter assess whole-plant physiological functionality during a drought event in the Eastern Cape, South Africa. This is the first study in Subtropical Thicket to quantify in situ hydraulic functional integrity under a natural drought event testing the leading hypothesis describing tree mortality – hydraulic dysfunction. This chapter firstly, investigates hydraulic traits (e.g., turgor loss point) and describe key physiological thresholds (e.g., P50) for maintaining function during drought. Secondly, levels of native embolism were determined under drought conditions and combined with measurements of xylem vulnerability to embolism providing an estimation of degree of hydraulic dysfunction experienced by six dominant woody canopy species in Subtropical Thicket – to quantify interspecific drought tolerance and susceptibility. Subtropical Thicket species exhibited remarkable tolerance towards desiccation (TLP from as low as -3MPa) and hydraulic functional resistance to embolism (P50 value as low as -7.89MPa). The observed unexpected drought resilience of subtropical derived lineages highlights the intrinsic evolutionary role aridification had, selecting for greater embolism resistance and community-level conservatism in drought resistance of Subtropical Thicket. The level of native embolism and hydraulic safety margins identified two species (Schotia latifolia and Polyagla myrtifolia) that were the most vulnerable, and a third (Pappea capensis) moderately vulnerable, then the remaining studied species – this could result in community-level adjustments in species composition and structure under future projected climate change scenarios where, increased frequencies of drought events are anticipated. This retrospective assessment of canopy vigor with physiological functional thresholds evokes hydraulic dysfunction as the principal mechanism of observed Subtropical Thicket dieback to drought. This chapter provides crucial in situ data for predictive assertions around drought-induced mortality risk in a phylogenetically diverse and climatically unique biome of southern Africa; and is the first to identify critical hydraulic thresholds for tree species within this region. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Buttner, Daniel Harry
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55455 , vital:52017
- Description: Water availability is one of largest constraints on plant survival, growth, and species distribution globally. The recent escalation in tree mortality coupled with declining precipitation and amplified temperatures has implicated drought as a major cause behind many large-scale dieback events observed across the world. Raising the question, what makes some species more resistant and persist while others dwindle and vanish from the landscape? The observed variability in species drought susceptibility demonstrates the complexity of physiological responses of plants to changes in water availability. Hydraulic dysfunction in plants has been purported to be the key mechanism behind drought-induced mortality provoking interest in hydraulic traits and critical thresholds of xylem physiological function. The capability of species to maintain hydraulic functionality under drought strongly influences the survival and general productivity towards water deficits. Hence, two core objectives, and subsequently aims, of this thesis are firstly to investigate the effect of drought on Subtropical Thicket vegetation health and productivity, and secondly to examine the underpinning physiological mechanisms and functional thresholds relaying speciesspecific drought vulnerability within this semi-arid biome. In first data chapter, this thesis offers an assessment of vegetation change under drought and its influence on plant physiological function and productivity across a subsection of Subtropical Thicket distribution. Additionally, this chapter provides a regional scale perspective of drought on Subtropical Thicket flora in the Eastern Cape of South Africa. A severe anomalous dieback event, which coincided with extreme, accumulative drought conditions was observed in 2020. Employing a combination of field-based approaches and remote sensing, this chapter aimed to provide a comprehensive report of the extent and severity of crown defoliation and canopy dieback following this event, additionally describing predisposing and compounding factors. Based on Standardized Precipitation Evapotranspiration and Standardized Precipitation Indices this event began in 2015 and coincided with amplified temperatures, exacerbating evaporative demand. Aerial UAV surveys and field-based investigations were undertaken. Remotely sensed (RS) indices provided an avenue for extensive spatiotemporal investigations to uncover the extent of drought-related impact on vegetation productivity and discuss potential underpinning mechanisms behind drought-induced mortality in Subtropical Thicket. Leveraging long-term time series RS data, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), from Moderate Resolution Imaging Spectroradiometer (MODIS) satellites as a proxy vegetation physiological status in combination with SPI and SPEI describing drought condition and groundbased surveying defining canopy vitality condition this study incidentally addressed the aim of endeavoring to link drought-induced mortality and early warning symptoms observed in the field with RS time series data to describe drought impacts across Subtropical Thicket. Furthermore, the findings of this chapter demonstrate the spatial and temporal heterogeneity in drought impacts on Subtropical Thicket. The recent drought of 2015 till 2021 is the longest documented period for the past 50 years in which there has been no accumulated net positive water availability, this apparently perpetual state of water deficiency has enacted a high cost for vegetation productivity and growth for the study area, exhibited well by average NDVI values of less than -0.5 for over 70% of the research site. The findings of this chapter report, to the contrary of anecdotal suggestions in the literature, on the intrinsic tolerance of Subtropical Thicket and that ii drought has a far more significant role on overall vegetation productivity, growth, and mortality in this region. The second data chapter assess whole-plant physiological functionality during a drought event in the Eastern Cape, South Africa. This is the first study in Subtropical Thicket to quantify in situ hydraulic functional integrity under a natural drought event testing the leading hypothesis describing tree mortality – hydraulic dysfunction. This chapter firstly, investigates hydraulic traits (e.g., turgor loss point) and describe key physiological thresholds (e.g., P50) for maintaining function during drought. Secondly, levels of native embolism were determined under drought conditions and combined with measurements of xylem vulnerability to embolism providing an estimation of degree of hydraulic dysfunction experienced by six dominant woody canopy species in Subtropical Thicket – to quantify interspecific drought tolerance and susceptibility. Subtropical Thicket species exhibited remarkable tolerance towards desiccation (TLP from as low as -3MPa) and hydraulic functional resistance to embolism (P50 value as low as -7.89MPa). The observed unexpected drought resilience of subtropical derived lineages highlights the intrinsic evolutionary role aridification had, selecting for greater embolism resistance and community-level conservatism in drought resistance of Subtropical Thicket. The level of native embolism and hydraulic safety margins identified two species (Schotia latifolia and Polyagla myrtifolia) that were the most vulnerable, and a third (Pappea capensis) moderately vulnerable, then the remaining studied species – this could result in community-level adjustments in species composition and structure under future projected climate change scenarios where, increased frequencies of drought events are anticipated. This retrospective assessment of canopy vigor with physiological functional thresholds evokes hydraulic dysfunction as the principal mechanism of observed Subtropical Thicket dieback to drought. This chapter provides crucial in situ data for predictive assertions around drought-induced mortality risk in a phylogenetically diverse and climatically unique biome of southern Africa; and is the first to identify critical hydraulic thresholds for tree species within this region. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
Agro-morphological characterization and investigations into the response of yellow Quality Protein Maize (QPM) genotypes to low soil pH
- Authors: Bobotyana, Simthandile
- Date: 2021-04
- Subjects: Corn as food , Plants--Drought tolerance
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20528 , vital:46087
- Description: Maize (Zea mays L) is an essential food grain crop in South Africa and is mainly grown under rainfed conditions by small-scale farmers. Quality Protein Maize (QPM) contains a higher level of two essential amino acids, tryptophan, and lysine when equated to normal maize. Therefore, the QPM in communities is a vital cereal where maize is a staple crop. Among the significant abiotic stresses that adversely affect maize productivity, such as soil fertility. Low soil pH or soil acidity results in nutrient deficiencies, as well as the toxicity of minerals such as manganese (Mn), aluminium (Al), and iron (Fe). The objectives of the study were to: (1) Characterize yellow QPM inbred lines and testcross hybrids for agro-morphological variability under optimum conditions, (2) Determine the response of QPM inbred lines and testcross hybrids to Al toxicity, and (3) Estimate the combining ability of QPM genotypes for the tolerance to Al toxicity. The laboratory assessment for tolerance to Al toxicity revealed a negative relationship between relative root growth RRG and hematoxylin staining; among the inbred lines, the genotype 8Y, 17Y, and 7Y had the highest RRG and net root growth (NRG) values and exhibited the highest tolerance to Al tolerance with the least hematoxylin staining. Inbred lines 12Y, 16Y, 19Y, 2Y, 20Y, 24Y, 30Y, 27Y, 34Y, 4Y, and 11Y were moderately tolerant. On the other hand, inbred lines 13Y, 18Y, and QSY5 had the least RRG were susceptible. Forty-four testcross hybrids were generated by crossing 22 QPM inbred lines with two open-pollinated variety (OPV) testers. These hybrids were evaluated together with five checks for different agronomic traits. The hybrids were planted in the summer season of 2017/18 and 2018/19 under rain-fed conditions 7 x 7 alpha lattice design was used. The significant variations among the genotypes for grain yield and most other agronomic traits under optimum, acidic conditions and across environments on combined analysis of variance. The hybrid was 14Y x NC (3.22 t/ha), followed by QSY5 x NC (3.02 t/ha) showed the highest yielding. The mean plant height was 226.23 cm, with ranges 197.60 to 254.85cm. The number of kernels per ear was 35, with a range from 29.45 to 40.25. Conversely, the mean ear length was 19.30 cm with a range of 17.65 to 20.95 cm, and the mean ear diameter ranged from 13,50 to 16,05 cm. The highest yielding hybrid, according to ranking, was 14Y x NC (2,93t/ha), which was ranked number 3, followed by 3Y x NC (2,83 t/ha), which was ranked number 4. Twenty-two yellow QPM inbred lines were evaluated for agro-morphological characteristics. A randomized complete block design with three replicates was used under acidic and normal soil conditions at two locations. The mean performance of inbred lines for grain yield ranged from 1.6 t/ha to 3.1 t/ha under optimum conditions, whereas it ranged from 1.1.t/ha to 1.7 t/ha under an acidic environment. The highest grain yielding genotypes under the optimum environment were 14Y, 7Y, and QSY5, while, in the acidic environment, the highest yielders were 3Y, QSY5, and 17Y. The lowest grain yielder under the optimum environment was 16Y at 1.5 t/ha, whereas 6Y, 7Y, 8Y, and 29Y were the most moderate yielders under the acidic environment. Grain yield displayed positive and significant (p<0,05) correlation with ear height (0.59), plant height (0.55), leaf length (0.18), number of leaves (0.37), number of ears per plot (0,54), number of kernels per row, number of rows per ear and thousand kernel weight. Combined ANOVA revealed that the environment effect was significant for all traits except the number of rows per ear and the number of ears in both environments. A total of 71 genotypes (22 inbred lines, forty-four single crosses, and five checks) were evaluated using a 7 x 7 alpha lattice design with two replications in combining ability. Across environments, the analysis showed a mean grain yield record of hybrids that ranged from 1.78 t/ha to 3.42 t/ha. Combined analysis showed only about 4 percent of the 44 hybrids had better grain yield than hybrid checks, whereas about 11 percent of the 44 hybrids had higher grain yield than two of the five hybrid checks. The highest yielding hybrid was 14Y x NC followed by QSY5 x NC. The Mid-parent heterosis (MPH) for grain yield ranged from -32.70 for 11YxObat to 16.50 percent for 14YxNC among the top-yielding genotypes. The highest positive mid-parent heterosis (MPH) for grain yield was observed in hybrid 14YxNC followed by QSY9xNC, QSY5xOBAT, 3YxNC, 13YxNC and 4YxOBAT, while the remaining hybrids exhibited negative estimates. Inbred lines' proportional contributions to the total variances were much higher than the testers for all traits. Whereas the inbred lines' proportional contribution was lower than the interaction of line x tester except on the number of ears which displayed the highest estimates of variances due to SCA effects, significant variation was observed. The GCA effects on grain yield in both environments generally showed no significant difference among inbred lines except for inbred lines such as QSY5 and 34Y but were positive. The selected crosses showed significant SCA effects in a few agronomic yield-related traits in the combined analysis. Among the hybrids, the only crosses that showed significant and positive SCA effects for grain yield were 25YxNC under optimum and 34YxObat under acidic environment. The inbred lines were assessed for tolerance to Al toxicity under laboratory conditions. Overall, the study identified soil acidity tolerant QPM inbred lines with an excellent combining ability for high-yielding QPM test hybrids, grain yield, and related traits. , Thesis (MSc) (Agriculture, Crop Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Bobotyana, Simthandile
- Date: 2021-04
- Subjects: Corn as food , Plants--Drought tolerance
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20528 , vital:46087
- Description: Maize (Zea mays L) is an essential food grain crop in South Africa and is mainly grown under rainfed conditions by small-scale farmers. Quality Protein Maize (QPM) contains a higher level of two essential amino acids, tryptophan, and lysine when equated to normal maize. Therefore, the QPM in communities is a vital cereal where maize is a staple crop. Among the significant abiotic stresses that adversely affect maize productivity, such as soil fertility. Low soil pH or soil acidity results in nutrient deficiencies, as well as the toxicity of minerals such as manganese (Mn), aluminium (Al), and iron (Fe). The objectives of the study were to: (1) Characterize yellow QPM inbred lines and testcross hybrids for agro-morphological variability under optimum conditions, (2) Determine the response of QPM inbred lines and testcross hybrids to Al toxicity, and (3) Estimate the combining ability of QPM genotypes for the tolerance to Al toxicity. The laboratory assessment for tolerance to Al toxicity revealed a negative relationship between relative root growth RRG and hematoxylin staining; among the inbred lines, the genotype 8Y, 17Y, and 7Y had the highest RRG and net root growth (NRG) values and exhibited the highest tolerance to Al tolerance with the least hematoxylin staining. Inbred lines 12Y, 16Y, 19Y, 2Y, 20Y, 24Y, 30Y, 27Y, 34Y, 4Y, and 11Y were moderately tolerant. On the other hand, inbred lines 13Y, 18Y, and QSY5 had the least RRG were susceptible. Forty-four testcross hybrids were generated by crossing 22 QPM inbred lines with two open-pollinated variety (OPV) testers. These hybrids were evaluated together with five checks for different agronomic traits. The hybrids were planted in the summer season of 2017/18 and 2018/19 under rain-fed conditions 7 x 7 alpha lattice design was used. The significant variations among the genotypes for grain yield and most other agronomic traits under optimum, acidic conditions and across environments on combined analysis of variance. The hybrid was 14Y x NC (3.22 t/ha), followed by QSY5 x NC (3.02 t/ha) showed the highest yielding. The mean plant height was 226.23 cm, with ranges 197.60 to 254.85cm. The number of kernels per ear was 35, with a range from 29.45 to 40.25. Conversely, the mean ear length was 19.30 cm with a range of 17.65 to 20.95 cm, and the mean ear diameter ranged from 13,50 to 16,05 cm. The highest yielding hybrid, according to ranking, was 14Y x NC (2,93t/ha), which was ranked number 3, followed by 3Y x NC (2,83 t/ha), which was ranked number 4. Twenty-two yellow QPM inbred lines were evaluated for agro-morphological characteristics. A randomized complete block design with three replicates was used under acidic and normal soil conditions at two locations. The mean performance of inbred lines for grain yield ranged from 1.6 t/ha to 3.1 t/ha under optimum conditions, whereas it ranged from 1.1.t/ha to 1.7 t/ha under an acidic environment. The highest grain yielding genotypes under the optimum environment were 14Y, 7Y, and QSY5, while, in the acidic environment, the highest yielders were 3Y, QSY5, and 17Y. The lowest grain yielder under the optimum environment was 16Y at 1.5 t/ha, whereas 6Y, 7Y, 8Y, and 29Y were the most moderate yielders under the acidic environment. Grain yield displayed positive and significant (p<0,05) correlation with ear height (0.59), plant height (0.55), leaf length (0.18), number of leaves (0.37), number of ears per plot (0,54), number of kernels per row, number of rows per ear and thousand kernel weight. Combined ANOVA revealed that the environment effect was significant for all traits except the number of rows per ear and the number of ears in both environments. A total of 71 genotypes (22 inbred lines, forty-four single crosses, and five checks) were evaluated using a 7 x 7 alpha lattice design with two replications in combining ability. Across environments, the analysis showed a mean grain yield record of hybrids that ranged from 1.78 t/ha to 3.42 t/ha. Combined analysis showed only about 4 percent of the 44 hybrids had better grain yield than hybrid checks, whereas about 11 percent of the 44 hybrids had higher grain yield than two of the five hybrid checks. The highest yielding hybrid was 14Y x NC followed by QSY5 x NC. The Mid-parent heterosis (MPH) for grain yield ranged from -32.70 for 11YxObat to 16.50 percent for 14YxNC among the top-yielding genotypes. The highest positive mid-parent heterosis (MPH) for grain yield was observed in hybrid 14YxNC followed by QSY9xNC, QSY5xOBAT, 3YxNC, 13YxNC and 4YxOBAT, while the remaining hybrids exhibited negative estimates. Inbred lines' proportional contributions to the total variances were much higher than the testers for all traits. Whereas the inbred lines' proportional contribution was lower than the interaction of line x tester except on the number of ears which displayed the highest estimates of variances due to SCA effects, significant variation was observed. The GCA effects on grain yield in both environments generally showed no significant difference among inbred lines except for inbred lines such as QSY5 and 34Y but were positive. The selected crosses showed significant SCA effects in a few agronomic yield-related traits in the combined analysis. Among the hybrids, the only crosses that showed significant and positive SCA effects for grain yield were 25YxNC under optimum and 34YxObat under acidic environment. The inbred lines were assessed for tolerance to Al toxicity under laboratory conditions. Overall, the study identified soil acidity tolerant QPM inbred lines with an excellent combining ability for high-yielding QPM test hybrids, grain yield, and related traits. , Thesis (MSc) (Agriculture, Crop Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-04
An assessment of the key factors that may impact the future demand for red meat in South Africa
- Authors: Pearce, Nathan
- Date: 2021-04
- Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53019 , vital:44887
- Description: The global human population is estimated to be in excess of nine billion by the year 2050, and the added population is expected to put further pressure on already over- extended resources such as food and water. Increased demand, positive growth and record high prices should be encouraging for the red meat industry. Despite all the positives such as the growth in the world population and the consumer’s ability to spend, the popularity of red meat around the world and in South Africa is continually declining in favour of white meat and other non-meat proteins. Although red meat will often be the most expensive component of any diet, the nutritional value that red meat offers as part of a healthy and balanced eating plan, should not be understated. This study intends to identify and assess factors that may impact on the future sustainable demand for red meat. Sixty-two adults were surveyed through an electronic questionnaire to assess their views on red meat consumption in South Africa. A set of 52 questions were deduced from the main focus and objectives. The data was analysed and conclusions derived from it. The results show that the demand for red meat is sustainable if outlets selling red meat are accessible and the preference for red meat remains, even with stiff competition from substitutes like pork, chicken and vegetables. , Thesis (MBA) -- Faculty of Business and Economic Sciences, NMU Business School, 2021
- Full Text: false
- Date Issued: 2021-04
- Authors: Pearce, Nathan
- Date: 2021-04
- Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53019 , vital:44887
- Description: The global human population is estimated to be in excess of nine billion by the year 2050, and the added population is expected to put further pressure on already over- extended resources such as food and water. Increased demand, positive growth and record high prices should be encouraging for the red meat industry. Despite all the positives such as the growth in the world population and the consumer’s ability to spend, the popularity of red meat around the world and in South Africa is continually declining in favour of white meat and other non-meat proteins. Although red meat will often be the most expensive component of any diet, the nutritional value that red meat offers as part of a healthy and balanced eating plan, should not be understated. This study intends to identify and assess factors that may impact on the future sustainable demand for red meat. Sixty-two adults were surveyed through an electronic questionnaire to assess their views on red meat consumption in South Africa. A set of 52 questions were deduced from the main focus and objectives. The data was analysed and conclusions derived from it. The results show that the demand for red meat is sustainable if outlets selling red meat are accessible and the preference for red meat remains, even with stiff competition from substitutes like pork, chicken and vegetables. , Thesis (MBA) -- Faculty of Business and Economic Sciences, NMU Business School, 2021
- Full Text: false
- Date Issued: 2021-04
Work-family conflict, stress and some demographic and occupational variables among female factory workers in East London, South Africa
- Authors: Dywili, Mtutuzeli
- Date: 2011
- Subjects: Work and family -- South Africa , Job stress -- South Africa , Women employees -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24128 , vital:62382
- Description: The study examines work-family conflict, stress, and some demographic and occupational variables among female factory workers in East London, South Africa. The participants were female factory workers in East London, South Africa. The independent variables for the study were, demographic and occupational variables, while stress is the dependent variable. Work-family conflict is dependent on demographic and occupational variables, while on the other hand is independent to stress. The demographic variables concerned are age, marital status, number of children and age of the last born child. The occupational variable on the other hand is occupational level, i.e. managerial versus non-managerial. The measuring instruments were a self-designed questionnaire to measure the demographic and occupational variables, a questionnaire developed by Stephens and Sommer (1996) to measure work-family conflict (cronbach’s alpha = 0,90) and the Effort – Reward Imbalance (ERI) questionnaire (Pikhart, Bobak, Siegrist, Pajak, Rywick, Kyshegyi, Gostaus, Skodova& Marmot, 1996) to measure stress at workplace. Cronbach’s alpha for the whole questionnaire reaches the value of 0,89. , Thesis (MCom) -- Faculty of Management and Commerce, 2011
- Full Text:
- Date Issued: 2011
- Authors: Dywili, Mtutuzeli
- Date: 2011
- Subjects: Work and family -- South Africa , Job stress -- South Africa , Women employees -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24128 , vital:62382
- Description: The study examines work-family conflict, stress, and some demographic and occupational variables among female factory workers in East London, South Africa. The participants were female factory workers in East London, South Africa. The independent variables for the study were, demographic and occupational variables, while stress is the dependent variable. Work-family conflict is dependent on demographic and occupational variables, while on the other hand is independent to stress. The demographic variables concerned are age, marital status, number of children and age of the last born child. The occupational variable on the other hand is occupational level, i.e. managerial versus non-managerial. The measuring instruments were a self-designed questionnaire to measure the demographic and occupational variables, a questionnaire developed by Stephens and Sommer (1996) to measure work-family conflict (cronbach’s alpha = 0,90) and the Effort – Reward Imbalance (ERI) questionnaire (Pikhart, Bobak, Siegrist, Pajak, Rywick, Kyshegyi, Gostaus, Skodova& Marmot, 1996) to measure stress at workplace. Cronbach’s alpha for the whole questionnaire reaches the value of 0,89. , Thesis (MCom) -- Faculty of Management and Commerce, 2011
- Full Text:
- Date Issued: 2011
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