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A gender analysis of restaurant employee profiles and perceptions in South Africa.
(2022) Mzolo , Sandile Padayachee.; Bob, Urmilla.
The restaurant industry is highly variable and responsive to customer demands and changes. It is a major industry that contributes to economic development and job creation. There is increasing focus on restaurant employees with limited focus on gender aspects which include wage gaps, occupational segregation, advancement opportunities and working conditions that apply to the tourism and hospitality sector more generally. It is in this context that the study undertakes an analysis of restaurant employee profiles and perceptions in South Africa to better understand employee trends and practices from a gender perspective. Employee surveys were conducted at 402 restaurants in selected South African cities (Cape Town, Durban and Johannesburg representing cities in South Africa with the largest number of restaurants and Pietermaritzburg and Polokwane representing cities with lower numbers of restaurants) as part of a National Department of Tourism funded study was subjected to a gendered analysis. In total, 1 869 surveys were completed at the 402 purposively selected restaurants. Some of the key findings are that restaurants in South Africa, as is the trend globally, employ a generally youthful and female population with close to a third being foreigners. A trend that is dissimilar to global patterns is that in South Africa most employees (irrespective of gender) in the restaurant industry work on a permanent rather than a casual or temporary basis although the wages received were relatively low with males on average earning more than females. Furthermore, almost all employees earn a salary with half of the respondents indicating tips as well. The results indicate the importance of the restaurant industry as an employer in South Africa. The relatively high turnover suggests areas of employee dissatisfaction which include low salaries as well as limited promotion opportunities, rewards and benefits. The main skills required in the restaurant industry identified by employees were emotional/ behavioral attributes, functional skills, and knowledge-based and physical skills, with the customer-centric orientation of the skills needed being evident. Very few gender differences were noted in relation to skills/ attributes needed for positions in the restaurant industry, which is contradictory to assertions in the literature. This suggests that gendered recruiting and occupational segregation are problematic since both males and females identify similar skills as being important. Key recommendations forwarded are to further examine employee vulnerabilities in the restaurant sector, especially in relation to specific gender issues such as harassment experienced which was not included in the survey used in this study. Future research should also look at perceptions of whether tips should be retained as a form of remuneration, gender influences when recruiting and promoting staff and job security issues. Training of staff in relation to dealing with customers as well as addressing concerns that lead to high staff turnover are also areas identified that need attention. More generally, there is a need to rethink training for the restaurant sector given that generally qualifications are not required. Finally, it is recommended that COVID-19 impacts be better understood and addressed.
The relationship between social capital and mental health in South Africa: a comparison by gender.
(2024) Mancwatela , Azasiwe.; Vermaak , Claire Lauren.; Dobreva , Ralitza Vassileva.
Social capital, which encompasses the strength of social networks, trust, and community ties, has received growing attention for its influence on mental well-being. Research shows that social capital plays a key role in promoting positive mental health and protecting against mental health challenges, particularly depression. This study examines the relationship between social capital and mental health in South Africa, with a particular focus on how gender may shape these dynamics. Globally, a wide range of studies have demonstrated that social capital can protect against depression and other mental health issues. In South Africa, however, the impact of social capital is particularly complex, shaped by the country’s history of colonialism, apartheid, and social fragmentation. Understanding how social capital influences mental health in this context is crucial for addressing mental health challenges in the country. Using longitudinal data from the National Income Dynamics Study (NIDS), which provides a detailed picture of South African society, this study explores the relationship between social capital and depression for African adults. Depression is measured using the CESD-10 score, which rates the extent of depression on a continuous scale, as well as a binary measure of depression. The study takes a gendered approach to examine how the relationship between social capital and mental health may differ for men and women, using statistical methods such as pooled OLS, fixed effects, and logit fixed effects models. The study finds that neighbourhood crime and violence are strongly linked to higher levels of depression for both genders, with men being more vulnerable to these environmental stressors. Neighbourhood attachment acts as a protective factor for women, reducing depression. The findings suggest that for men, religious and communal activities provide essential emotional support, while women may benefit from a wider range of social networks. Additionally, the quality of trust with neighbours plays a more significant role in men’s mental health.
Investigating South Africa’s exposure to potential currency crises.
(2025) Hadebe , Ntokozo Thabiso.; Nyati , Malibongwe Cyprian.; Msomi , Simiso Sinqumo Sanele Gary.
This study investigates South Africa's potential exposure to currency crises, aiming to identify effective economic indicators for anticipating such crises. Using annual data from 1994 to 2020, a probit model analysis and the Market Turbulence Index (MTI) are employed to facilitate this investigation. The results suggest that none of the 10 variables identified in empirical literature have predictive power in the South African context. The insignificant findings can be attributed to data frequency restrictions, as annual data was used instead of daily, weekly, or monthly data
due to limited public access to monthly statistics. The study concludes that the modelling approach employed may not be helpful for policymakers and central banks in predicting currency crises in South Africa. However, the use of higher frequency data and additional variables, such as political instability, may improve the significance and predictability of currency crises. Despite the insignificant results, the study highlights the potential adoption of the MTI in identifying crisis thresholds. With higher frequency data and more influential variables, this study can contribute significantly to the literature, particularly in a country like South Africa with a volatile economic climate.
Genetic analysis and hybrid prediction in tropical maize (Zea mays L.) using phenotypic and single nucleotide polymorphic markers.
(2024) Gunundu, Rodreck.; Hussein, Shimelis.
Maize (Zea mays L., 2n = 2x = 20) is a commodity crop serving the food, feed, and processing industries globally. The productivity of maize in Africa remains low (< 2 t/ha) due to various yieldlimiting factors, including abiotic stresses (such as drought, heat stress, flooding, waterlogging, erosion and poor soil health), and biotic stresses (e.g. foliar diseases and insect pests). Limited adoption of new high yielding varieties, slow rate of varietal turnover , socio-economic constraints, and policy issues further hinder productivity. Seed Co Limited is a Pan-African seed company involved in the research, development, and commercialization of seeds of major food security grain crops, including maize. The Seed Co breeding program aims to enhance the yields of new generation maize cultivars via hybrid breeding by utilizing complementary and contrasting inbred lines. New lines and experimental hybrids are developed and phenotyped using economic agronomic traits and genotyped using high-resolution Single Nucleotide Polymorphism (SNP) markers to facilitate effective selection. Integrating phenotypic and genomic selection accelerates the development of inbred lines with desirable traits to create high-performing single crosses and three-way hybrids. The new hybrids should undergo rigorous field testing for yield gains and stability across various locations to guide cultivar release and commercialization. Therefore, to complement this breeding initiative, the objectives of the study were: to assess a maize germplasm panel's genetic diversity and population structure comprising 182 founder lines and 866 derived inbred lines using Single Nucleotide Polymorphism (SNP) markers to identify genetically unique lines for hybrid breeding, to conduct genome-wide prediction of yield and component traits using qualitative and quantitative phenotypic traits and SNP markers based on the additive-dominant genomic best linear unbiased predictions model to compute genomic estimated breeding values and genomic estimated genetic values to guide inbred line development and hybrid breeding, to assess the gains in yield and yield components among single cross maize hybrids selected through genomic prediction across representative locations to guide breeding and production and to determine the combining ability effects of newly selected inbred lines and quantify the magnitude of heterosis and genotype by environmental interaction (GEI) effects of single cross hybrids to select and recommend contrasting elite lines and experimental hybrids.
In the first study, 182 founder and 866 derived maize inbred lines were characterized for genetic diversity and population structure analyses using SNP markers to identify genetically unique lines for hybrid breeding through beneficial allelic combinations. Genotyping was performed using the Affymetrix platform for the 182 founder lines (1201 SNP markers) and the Midseq platform for the 866 derived lines (1484 markers). Moderate genetic variation with genetic distance ranging from 0.004 to 0.44 (mean: 0.25) for founder lines and 0.004 to 0.34 (mean: 0.13) for derived lines was observed. Heterozygosity values ranged from 0.00 to 0.24 for both lines. About 82% of the 1201 markers and 84% of the 1484 markers exhibited polymorphism information content ranging from 0.25 to 0.50, detecting a high level of genetic diversity and that the SNPs were highly informative in distinguishing the tested lines. Analysis of molecular variance revealed significant genetic differences (P ≤ 0.001) among and within populations in the founder and derived lines. Notably, within-population variations accounted for 97% (founder lines) and 88.38% (derived lines) of the detected variations. Population structure analysis identified three subpopulations among founder lines and two among derived lines, which was supported by cluster analysis. Based on pairwise comparisons, genetically distant lines were selected, including G15NL337 and G15NL312 (Cluster 1), 15ARG152 and RGS-PL44 (Cluster 2), RGS-PL44 and 15ARG149 (Cluster 2), and RGS-PL33 and RGS-PL44 (Cluster 2). The selected lines are genetically distinct and recommended for marker-assisted hybrid maize breeding to leverage beneficial alleles.
The second study genotyped 1,102 genetically diverse inbred lines from two heterotic groups (N3 and SC) using high-density SNP markers. The 1,102 lines and 4 testers were crossed in a line-by-tester design to generate 2,830 single cross hybrids (SCHs). Phenotypic data were collected from field trials with the following SCHs: 684 evaluated at five locations in 2018/19, 760 at four locations (2019/20), 646 at four locations (2020/21), and 740 at four locations (2021/22) summer seasons in Zimbabwe. The trials were laid out in a 6 x 7 alpha lattice design with two replications at each site. 20 highperforming and contrasting inbred lines with the highest genomic estimated breeding values (GEBVs) and genomic estimated genetic values (GEGVs), each from the two heterotic groups, were identified for genetic advancement, combining ability tests and commercial hybrid development. 20 highperforming candidate SCHs with high GEGVs were identified for three-way hybrid development, variety registration and commercialization.
In the third study, 30 SCHs were developed from 11 inbred lines (6 from the N3 group and 5 from the SC group) with the highest predicted GEGVs for grain yield and associated traits using the genotypic best linear unbiased prediction (GBLUP) model. The lines were crossed using a factorial mating design with the six N3 lines used as female and five SC lines as male. The derived 30 SCHs and six commercial single cross check hybrids were field evaluated in seven locations, four in Zimbabwe and three in Zambia using a 6 x 6 alpha lattice design with two replications at each location. A combined analysis of variance revealed significant (P≤0.05) variation among the hybrids for the assessed 11 quantitative traits. Significant yield gains were realized over the mean of checks (at 13.09%), mean of the population (10.83%) and mean of best check (1.47%). Moderate to high broad-sense heritability (50 to 94%) and genetic advance were recorded for most of the assessed traits, indicating the success of selection assisted by genomic predictions. The study identified three best single cross hybrids (i.e., CTL03 x G16NL721, CTL03 x G17NL544 and GS-PL07 x G17NL544) with high and stable yields and recommended for commercialization.
In the fourth study, 11 elite inbred lines (6 female parents from N3 and 5 male parents from SC group) were crossed using a factorial mating design, resulting in 30 SCHs. The lines were selected based on the highest GEGVs for yield and component traits through GS using the GBLUP model. The 30 SCHs and six commercial check hybrids were field evaluated at seven locations (four in Zimbabwe and three in Zambia) during the 2022/2023 summer season. The trials were arranged in a 6 x 6 alpha lattice design with two replications at each location. Data were recorded on yield and yield components, and general combining ability (GCA) and specific combining ability (SCA) effects were computed. Significant GCA effects for grain yield (GY) were noted for lines CTL03, G17NL544, G16NL721, and GS-PL07, while significant SCA effects were recorded for crosses 15AG163 x G16NL679, G15NL304 x G17NL642, and 15AG162 x G16NL679. The additive main effects and multiplicative interaction (AMMI) model explained 38.95%, 50.58% and 7.24% of the total variation in GY due to genotype (G), environment (E), and genotype x environment interaction (GEI) effects in that order. The test locations were clustered into two mega environments: Rattray Arnold Research Station (RARS), Agricultural Research Trust (ART), Mpongwe Research Station (MPRS), and Lusaka West Research Station (LWRS) (Environment 1), and Mkushi Research Station (MKRS), Stapleford Research Centre (STAP), and Kadoma Research Centre (KRC) (Environment 2). The genotype and genotype-by-environment interaction (GGE) biplot analysis identified hybrids G15NL304 x G17NL544 and 15AG162 x G17NL544 as high-yielding and stable, suitable for commercialization. The two mega-environments and the selected stable, high-yielding general and specific combiners are recommended for genotype evaluation and production in Zimbabwe, Zambia, and comparable agroecologies.
Overall, the present study identified contrasting and genetically delineated inbred lines and enhanced the existing heterotic groups using high-throughput SNP markers. Best-performing lines (e.g. CTL03 and GS-PL07) were selected from the N3 heterotic group and G17NL544 and G16NL721 from the SC heterotic group. New single cross hybrids, such as CTL03 x G16NL721, CTL03 x G17NL544, and GS-PL07 x G17NL544, were selected with grain yields of 8.38 t/ha, 8.24 t/ha, and 8.23 t/ha, respectively. The new experimental hybrids are recommended for three-way hybrid development or release following multi-environment evaluation.
Genetic analysis of agronomic traits among tropical and sub- tropical maize (Zea Mays L.) inbred lines for drought tolerance in South Africa.
(2024) Dube, Sweetbird Phindile.; Sibiya, Julia.
Maize (Zea mays L.) production plays a crucial role in the economies of most southern African countries. However, these countries have recently experienced significant decreases in maize yields due to the increased occurrence of drought events. In the future, the situation is anticipated to worsen. Several studies have predicted increased frequency and severity of droughts, highlighting South Africa as one of the global hotspots for climate change-induced drought events. Hence, it will be important to breed maize cultivars that can adapt to the prevalent climate challenges to meet the requirements of local and regional markets. Tropical and sub-tropical germplasm adapted to sub-Saharan African (SSA) environments can enhance the tolerance of South African maize to moisture stress. These genotypes are renowned for their native traits that ensure maize productivity in multiple-stress environments. Therefore, these genetic resources can provide a valuable source of genetic diversity needed to enhance the resilience of South African maize germplasm against climate change-related challenges, particularly drought stress. The knowledge of the mechanism regulating drought tolerance in maize will also facilitate the integration of the desired genes into local germplasm. Therefore, the specific objectives of the study were: (i) to assess genetic diversity and population structure of tropical and sub-tropical maize inbred lines using phenotypic traits and single nucleotide polymorphism (SNP) markers; (ii) to assess genetic variance parameters and heritability among tropical and subtropical maize inbred lines under well-watered and drought-stressed conditions; (iii) to identify candidate genes significantly associated with maize yield and yield component traits under well-watered and drought-stressed environments; and (iv) to evaluate the genotype by environment interaction of tropical and sub-tropical maize inbred lines under well-watered and drought-stressed environments and identify parental inbred lines for further breeding.
The first study assessed the genetic diversity and population structure among one hundred and twenty-eight (128) maize inbred lines sourced from the International Institute of Tropical Agriculture (IITA), the International Maize and Wheat Improvement Centre (CIMMYT), and the University of KwaZulu-Natal (UKZN). This was done using 15 phenotypic traits assessed across two locations and 11,450 SNP markers. The inbred lines showed highly significant (p < 0.001) levels of variability for traits such as days to anthesis, days to silking, plant height, and grain yield. This indicates substantial genetic variation among the studied inbred lines. The highest grain-yielding genotypes included TZISTR1190, TZISTR1261, CML540, CML571, and TZISTR1119, achieving yields of 5.9, 5.8, 5.6, 5.6, and 5.5 t ha-1, respectively. The modelbased population structure analysis revealed the existence of three sub-populations (K = 3) among the inbred lines. This was supported by the phenotypic and molecular hierarchical cluster analyses which grouped the inbred lines into three clusters, respectively.
The second study assessed the interrelationship between grain yield and its components among tropical and sub-tropical germplasm to confirm the utility of the traits in selecting highperforming inbred lines under well-watered and drought-stressed conditions. Analysis of variance revealed significant differences (p < 0.001) among genotypes for all traits. High heritability (H2) estimates were recorded for ear height (76.10%), plant height (62.74%), ear length (58.97%), and grain yield (64.02%) in a well-watered treatment. Under drought stress, ear height (61.98%) demonstrated the highest heritability, while all other traits exhibited heritability estimates below 50%. Correlation and principal component analyses identified traits such as field weight, kernels rows per ear, ear length, ear diameter, plant height, and ear height as significant factors with direct association with grain yield under well-watered and drought-stress environments.
The third experiment was a genome-wide association study conducted using a panel of 182 maize inbred lines, to reveal the genetic basis of ear height, ear length, ear diameter, kernels per row, kernel rows per ear under drought and well-watered conditions. The panel was genotyped using a 50,941-SNP array, of which 7119 SNPs together with the best linear unbiased estimates (BLUPs) were used for the GWAS using a mixed linear model. In total, 25 and 21 significant SNPs were detected for the traits under well-watered and drought-stressed environments, respectively. These loci included SNP 4583772 located on Chromosome (Chr) 2 which was significant for EH with pleiotropic effects for ED. In addition, SNP 2382814 located on Chr 7, significant for ED was co-localized under well-watered and drought-stressed environments. From the candidate regions of the 46 significant loci, 15 genes expressed in maize ear traits, participated in biological pathways such as amino acid biosynthesis, enzyme regulation, growth, and stress hormone function. These candidate genes included putative functional genes such as Zm00001e032263, Zm00001eb206490, Zm00001eb099810, Zm00001eb332890 (smk501 - small kernel 501), and Zm00001eb418870, of which Zm00001eb099810 is located on QTL for height above the ear. These results have the potential to be useful in starting marker-assisted selection and targeted trait introgression in maize under well-watered and drought-stressed conditions.
The fourth study examined the performance of the 182 tropical and sub-tropical inbred lines over five seasons at Ukulinga, Makhathini, and Cedara research stations in the KwaZulu-Natal province of South Africa. Genotype and genotype × environment (GGE) interaction effects were significant (p ≤ 0.001) for grain yield and related traits among the inbred lines. Notably, the GGE biplot clustered the environments into three distinct mega-environments. Inbred lines TZISTR1190, TZISTR1231, and TZ-14 exhibiting stable high yield in well-watered and drought-stressed conditions can be incorporated into local maize breeding pipelines to develop stable and high-yielding resilient hybrids.