Early Generation Selection of Bread Wheat (Triticum aestivum L.).

Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.Wheat (Triticum aestivum L.) is the third most important cereal crop after rice and maize globally. Dryland wheat production in South Africa is challenged by recurrent drought leading to low profitability for farmers. Development of drought tolerant wheat genotypes presents the most sustainable strategy to mitigate the effects of drought stress associated with climate change. In an attempt to develop drought tolerant wheat genotypes, the wheat research group at the University of KwaZulu-Natal (UKZN) in collaboration with the Agricultural Research Council-Small Grain Institute (ARC-SGI) developed a breeding population and advanced it to the F2 generation. The breeding population was developed through crosses involving selected promising parents with local drought susceptible cultivars. The F2 families need to be advanced to the F3 generation and selected for genetic advancement with regards to drought tolerance and important agronomic traits. Therefore, the overall objective of this study was to select superior drought tolerant bread wheat families at the F3 generation for further screening in advanced generations. The specific objectives of the study were: 1) to undertake early generation selection of wheat genotypes for drought tolerance and agronomic traits for genetic advancement, 2) to determine the combining ability effects and the mode of gene action that controls yield and yield components in selected wheat genotypes under drought-stressed and non-stressed conditions, and 3) to assess the association between yield and yield-components in wheat and identify the most important components to improve grain yield and drought tolerance. Seventy-eight genotypes consisting of 12 parents and their 66 F3 families were evaluated using a 13 x 6 alpha-lattice design with two replications in two contrasting water regimes under greenhouse and field conditions in the 2017/2018 growing season. The following agronomic traits were assessed: number of days to heading (DTH), days to maturity (DTM), plant height (PH), productive tiller number (TN), spike length (SL), spikelets per spike (SPS), kernels per spike (KPS), thousand kernel weight (TKW), fresh biomass (BI) and grain yield (GY). Highly significant differences (P<0.05) were observed for the assessed traits among the genotypes under the two water regimes. Variance components and heritability estimates among agronomic traits and yield showed high values for days to heading and fresh biomass under drought stress. Genetic advance values of 29.73% and 37.61% were calculated under drought-stressed and non-stressed conditions, respectively, for fresh biomass. The families LM02 x LM05, LM13 x LM45, LM02 x LM23 and LM09 x LM45 were relatively high yielding in both stressed and non-stressed conditions and are recommended for genetic advancement. The above data were subjected to combining ability analysis to discern best combiners. Significant general combining ability (GCA) effects of parents were observed for DTH, PH and SL in both the greenhouse and the field under drought-stressed and non-stressed conditions. The specific combining ability (SCA) effects of progenies were only significant for DTH under all testing conditions. The heritability of most traits was low (0 < h2 < 0.40) except for SL which showed moderate heritability of 0.41 under drought-stressed condition. The GCA/SCA ratio was below one for all the traits indicating the predominance of non-additive gene action. Low negative GCA effects were observed for DTH, DTM and PH on parental line LM17 in a desirable direction for drought tolerance. High positive GCA effects were observed on LM23 for TN and SL, LM04 and LM05 (for SL, SPS and KPS), LM21 (TKW), LM13 and LM23 (BI) and LM02, LM13 and LM23 for GY. Families LM02 x LM05 and LM02 x LM17 were the best performers across the test conditions. Significant correlations (P<0.05) were observed between GY with PH, TN, SL, KPS, TKW and BI under both drought-stressed and non-stressed conditions. Partitioning of correlation coefficients into direct and indirect effects revealed high positive direct effects of KPS and BI on GY under drought-stressed conditions. Among all the assessed traits, BI had significant simple correlations of 0.75 and 0.90, and high direct effects of 0.76 and 0.98 with grain yield under drought-stressed and non-stressed conditions, in that order. The top yielding genotypes such as LM02 x LM05, LM02 x LM23 and LM13 x LM45, showed high mean values for KPS, TKW and BI. The overall association analyses indicated that the latter three traits had significant influence on grain yield performance and are useful for selection of drought tolerant breeding populations of wheat. Overall, the present study identified promising families including LM02 x LM05, LM02 x LM23, LM09 x LM45 and LM13 x LM45 that have drought tolerance and suitable agronomic traits. These families can be advanced using the single seed descent selection method for further characterisation of end-use quality traits and comparison with local checks or commercial cultivars

Early generation selection of bread wheat (triticum aestivum L.) genotypes for drought tolerance.

Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.Wheat (Triticum aestivum L.) is the third most important cereal crop after rice and maize globally. Dryland wheat production in South Africa is challenged by recurrent drought leading to low profitability for farmers. Development of drought tolerant wheat genotypes presents the most sustainable strategy to mitigate the effects of drought stress associated with climate change. In an attempt to develop drought tolerant wheat genotypes, the wheat research group at the University of KwaZulu-Natal (UKZN) in collaboration with the Agricultural Research Council-Small Grain Institute (ARC-SGI) developed a breeding population and advanced it to the F2 generation. The breeding population was developed through crosses involving selected promising parents with local drought susceptible cultivars. The F2 families need to be advanced to the F3 generation and selected for genetic advancement with regards to drought tolerance and important agronomic traits. Therefore, the overall objective of this study was to select superior drought tolerant bread wheat families at the F3 generation for further screening in advanced generations. The specific objectives of the study were: 1) to undertake early generation selection of wheat genotypes for drought tolerance and agronomic traits for genetic advancement, 2) to determine the combining ability effects and the mode of gene action that controls yield and yield components in selected wheat genotypes under drought-stressed and non-stressed conditions, and 3) to assess the association between yield and yield-components in wheat and identify the most important components to improve grain yield and drought tolerance. Seventy-eight genotypes consisting of 12 parents and their 66 F3 families were evaluated using a 13 x 6 alpha-lattice design with two replications in two contrasting water regimes under greenhouse and field conditions in the 2017/2018 growing season. The following agronomic traits were assessed: number of days to heading (DTH), days to maturity (DTM), plant height (PH), productive tiller number (TN), spike length (SL), spikelets per spike (SPS), kernels per spike (KPS), thousand kernel weight (TKW), fresh biomass (BI) and grain yield (GY). Highly significant differences (P<0.05) were observed for the assessed traits among the genotypes under the two water regimes. Variance components and heritability estimates among agronomic traits and yield showed high values for days to heading and fresh biomass under drought stress. Genetic advance values of 29.73% and 37.61% were calculated under drought-stressed and non-stressed conditions, respectively, for fresh biomass. The families LM02 x LM05, LM13 x LM45, LM02 x LM23 and LM09 x LM45 were relatively high yielding in both stressed and non-stressed conditions and are recommended for genetic advancement. The above data were subjected to combining ability analysis to discern best combiners. Significant general combining ability (GCA) effects of parents were observed for DTH, PH and SL in both the greenhouse and the field under drought-stressed and non-stressed conditions. The specific combining ability (SCA) effects of progenies were only significant for DTH under all testing conditions. The heritability of most traits was low (0 < h2 < 0.40) except for SL which showed moderate heritability of 0.41 under drought-stressed condition. The GCA/SCA ratio was below one for all the traits indicating the predominance of non-additive gene action. Low negative GCA effects were observed for DTH, DTM and PH on parental line LM17 in a desirable direction for drought tolerance. High positive GCA effects were observed on LM23 for TN and SL, LM04 and LM05 (for SL, SPS and KPS), LM21 (TKW), LM13 and LM23 (BI) and LM02, LM13 and LM23 for GY. Families LM02 x LM05 and LM02 x LM17 were the best performers across the test conditions. Significant correlations (P<0.05) were observed between GY with PH, TN, SL, KPS, TKW and BI under both drought-stressed and non-stressed conditions. Partitioning of correlation coefficients into direct and indirect effects revealed high positive direct effects of KPS and BI on GY under drought-stressed conditions. Among all the assessed traits, BI had significant simple correlations of 0.75 and 0.90, and high direct effects of 0.76 and 0.98 with grain yield under drought-stressed and non-stressed conditions, in that order. The top yielding genotypes such as LM02 x LM05, LM02 x LM23 and LM13 x LM45, showed high mean values for KPS, TKW and BI. The overall association analyses indicated that the latter three traits had significant influence on grain yield performance and are useful for selection of drought tolerant breeding populations of wheat. Overall, the present study identified promising families including LM02 x LM05, LM02 x LM23, LM09 x LM45 and LM13 x LM45 that have drought tolerance and suitable agronomic traits. These families can be advanced using the single seed descent selection method for further characterisation of end-use quality traits and comparison with local checks or commercial cultivars

A Review: Assessment of Trace Metals in Municipal Sewage and Sludge: A Case Study of Limpopo Province, South Africa

Trace metals including nanosilver in our aquatic environment are on the increase in part due to discharge from municipal sewage and indirectly from leaching from abandoned mine tailings and from sludge spread on farmland. The presence of the trace metals will likely impact negatively on the aquatic environment in excess of background levels. This review reports on the concentration of trace metals in municipal sewage in Limpopo province and the impact on fish and human health. Human health risks associated with the consumption of contaminated fish are discussed. The presence of silver is also highlighted and the remedial actions that are available in reducing the health risks including positive outcomes are discussed. The source of silver may be from the use of silver nanoproducts. There is a need for a paradigm shift of zero effluent discharge and start with harvesting of metals from the sewage effluent and sludge in order to protect the environment

An investigation of revenue collection from tenants: a case study of the department of Public Works, Mashonaland East Province

This research focused on investigation on revenue collection from tenants using a case study of the Department of Public Works, Mashonaland East Province from 2009 to 2013. The researcher mainly used the primary data extracted by the use of questionnaires and Interviews Results of the study show that procedures used by the department in selecting lessees were not uniform as the department did not have standing, documented and systematic policy in place. The study also highlighted on the factors leading to escalation of outstanding rental revenue. Having analyzed all the factors, the greatest of them all was inadequate screening of prospective tenants by the department. The issue on trends in outstanding rental revenue was highlighted by the researcher. The only action taken by the department on defaulting tenants was by means of negotiations. Measures were non-existent for defaulting tenants and the tenants ended up having a culture of nonpayment of rentals. This prejudiced the Department of regular monthly rental income. The researcher recommends that the Department comes up with a documented and systematic evaluation policy that is uniformly applied to every prospective lessee

An investigation of the role played by the youth and their involvement in politics from 1980 to 2016â€: case study Mbare

This study investigates the role played by the youth and their involvement in politics from 1980 to 2016, basing on Mbare. The will look from the transition of Chibwidos and Mujibhasi from the war and their integration into the society and the army. The formation of the 5th Brigade and its deployment in Matabeleland and its practices on the local people which led to more than 20 000 deaths including women and children, due to hunger, torture and abductions. The failure of the government to act and rescue the people as it was part of the strategy which was to prolong its stay in power. The research also looks at the role played by the youths in land invasions of 2000 and the damage it brought to the communities and the country at large. Also brings to light the emergence of a new generation youths leaders who became active in politics and violence that occurred in Mbare. This study also looks at the formation of the youth brigades in 2000 by late Border Gezi and the role it played in ensuring that ZANU (PF) stayed in power. Furthermore the research looks at Chipangano and its extractives practises in Mbare, which led do devastation of properties, loss of human lives, torture and abductions. All this crimes are against humanity from 1980 to 2016 how they have gone unpunished, because they are done in the name of ZANU (PF). Interviews, books and internet sources have been extensively used by the researcher in gathering information. Personal observation has also allowed the researcher to compile the facts and finding of the study in a chronological manner

Determination of recharge and groundwater potential zones in Mhinga Area, South Africa

MESHWRDepartment of Hydrology and Water ResourcesThis study was focused on determining groundwater recharge and groundwater potential for Mhinga area in South Africa, which is a rural area that depends mainly on groundwater for domestic water supply. Numerical modelling was used to simulate the groundwater behaviour in the aquifer and estimate groundwater recharge. MIKE SHE and MIKE 11 models were coupled and used to estimate groundwater recharge within calibration and validation periods of 2007/07/01 to 2009/12/31 and 2010/01/01 to 2013/05/21, respectively. Due to limited data availability for Mhinga, modelling was carried out at quaternary scale and then localised to Mhinga area. Remotely sensed data (satellite images, shapefiles and maps) was used to produce the groundwater potential map for Mhinga. The data were assigned with weights using Saaty’s Analytical Hierarchy Process and overlain on ArcGIS platform. Borehole drilling statistics of the boreholes in A91H quaternary catchment were used to validate the groundwater potential map. In streamflow modelling using MIKE 11, values of Nash-Sutcliffe efficiency (NSE), correlation coefficient (R), root mean square error (RMSE) and mean absolute error (MAE) were 0.51-0.89, 0.73-0.97, 3.61-7.96 and 1.13-2.75, respectively. In integrated groundwater modelling using MIKE SHE, values of NSE, R, RMSE and MAE were 0.72-0.84, 0.87-0.93, 0.18-0.32 and 0.13-0.26, respectively. These values showed that MIKE SHE and MIKE 11 models had satisfactory performances. Groundwater recharge estimates were generally very low ranging from 0 to 2.75 mm/year, which constituted 0 – 0.42 % of Mean Annual Precipitation (MAP) for the A91H quaternary catchment. This was associated with high evapotranspiration (mean of approximately 4 mm/day) compared to the low precipitation levels (MAP of 656 mm/year). Moreover, in the low lying areas, with gentle slopes, low recharge between 0.2 – 0.4 mm was observed. The groundwater potential (GWP) map produced revealed that Mhinga is predominantly covered by regions of very low and low groundwater potential, which was associated with the type of geology. Area coverages of 34.47 % had very low, 51.39 % had low, 7.66 % had moderate and 6.48 % had high groundwater potential. Moderate to high groundwater potential zones were located along the geologic fault zones. In A91H, 112 unsuccessful boreholes were drilled, 69 (61.6 %) fell in the very low GWP zones, 16 (14.3 %) fell in the low GWP zones, 17 (15.2 %) fell in moderate GWP zones and 10 (8.9 %) fell in the high GWP zones. In the Mhinga, 19 unsuccessful boreholes were drilled of which, 11 (57.9%) fell in the very low GWP zones, while 6 (31.6%) fell in the low GWP zones and 2 (10.5%) fell in the moderate GWP zone. Hence 89.5% of all the unsuccessful boreholes drilled occurred in the very low to low GWP zones. It is concluded that the study area is mainly dominated by of areas with low recharge and very low to low groundwater potential. It is recommended that the MIKE SHE – MIKE 11 model and the GIS models should be developed further and improved as more data is collected to refine the conceptualisation of the aquifer

Assessment of Heavy Metals in Municipal Sewage Sludge: A Case Study of Limpopo Province, South Africa

Heavy metals in high concentrations can cause health and environmental damage. Nanosilver is an emerging heavy metal which has a bright future of use in many applications. Here we report on the levels of silver and other heavy metals in municipal sewage sludge. Five towns in Limpopo province of South Africa were selected and the sludge from their wastewater treatment plants (WWTPs) was collected and analysed. The acid digested sewage sludge samples were analysed using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) methods. The concentrations of silver found were low, but significant, in the range 0.22 to 21.93 mg/kg dry mass. The highest concentration of silver was found in Louis Trichardt town with a concentration of 21.93 ± 0.38 mg/kg dry mass while the lowest was Thohoyandou with a concentration of 6.13 ± 0.12 mg/kg dry mass. A control sludge sample from a pit latrine had trace levels of silver at 0.22 ± 0.01 mg/kg dry mass. The result showed that silver was indeed present in the wastewater sewage sludge and at present there is no DWAF guideline standard. The average Cd concentration was 3.10 mg/kg dry mass for Polokwane municipality. Polokwane and Louis Trichardt municipalities exhibited high levels of Pb, in excess DWAF guidelines, in sludge at 102.83 and 171.87 mg/kg respectfully. In all the WWTPs the zinc and copper concentrations were in excess of DWAF guidelines. The presence of heavy metals in the sewage sludge in excess of DWAF guidelines presents environmental hazards should the sludge be applied as a soil ameliorant

Virtual Dressing Room Mobile Application

&lt;p&gt;This abstract focuses on a digital platform designed to enhance the online shopping experience through the use of a virtual dressing room application. The application employs advanced augmented reality technology to enable customers to try on clothes virtually, thus eliminating the need for physical trial rooms. Through the use of a camera and other sensors, the application scans the customer's body and superimposes a digital image of the clothing onto their body. This allows customers to see how the clothing would look and fit before making a purchase decision. The virtual dressing room application has the potential to revolutionize the fashion industry by providing a seamless and personalized shopping experience for customers.&lt;/p&gt;&lt;p&gt;Keywords:- Augmented Reality, Digital platform, Tensorflow, OpenCV, Try-on clothes.&lt;/p&gt