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1

Kotey, Daniel Ashie. "Genetically modified (GM) maize cultivation by smallholders in the Eastern Cape Province of South Africa: Effects on target and non-target organisms and adoption challenges." Thesis, University of Fort Hare, 2017. http://hdl.handle.net/10353/5161.

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The use of genetically modified (GM) maize technology is subject to compliance with stewardship requirements and the adoption of specific management practices that promote the long-term effectiveness and environmental sustainability of the technology. For smallholders to comply with these requirements and adopt the desired management practices to ultimately benefit from the technology, they require information that creates awareness of the value of these requirements. To determine what information farmers receive about GM maize and how this information is disseminated to farmers, face to face interviews were conducted with 81 extension personnel and 210 smallhoder GM maize farmers in the Eastern Cape Province of South Africa. The effect of Bt maize introduction and management practices in smallholder maize agroecosystems in the Eastern Cape on Bt maize target [Busseola fusca (Fuller) (Lepidoptera: Noctuidae)] and non-target insect pests [Agrotis segetum (Denis & Schiffermüller) (Lepidoptera: Noctuidae), Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)] and a snail species, [Cornu aspersum (Müller) (Gastropoda: Helicidae)] was determined through laboratory, field and cage experiments. The effect of smallhoder farmers‟ GM maize cultivation practices on the profitability of GM maize technology was also determined through on-farm trials in different localities of the Eastern Cape identified as hot-spots for stem borer and weed infestation. Results of surveys indicated that extension personnel had a low level of awareness of GM maize technology stewardship requirements. GM maize technology was also largely disseminated to smallholder farmers through non-participatory approaches and print media sourced from GM seed companies. Although farmers had a high level of contact with extension services, they lacked access to information about GM maize technology. Smallholder farmers‟ level of awareness about GM maize and compliance with the requirement for the planting of non-Bt maize refuge areas adjacent to Bt maize was also very low. While Bt maize event (MON810) commonly cultivated by smallholder farmers in the Eastern Cape Province had a variable effect on A. segetum under laboratory conditions, it had no effect on the incidence of plants damaged by A. segetum and C. aspersum under field conditions. The incidence of H. armigera damage on Bt maize plants was however significantly affected by Bt maize. Populations of B. fusca collected from smallholder maize fields in the province were observed to be still highly susceptible to Bt maize. Results of on-farm evaluation of the profitability of GM maize revealed that stem borer pressure, growing conditions, input supplies and market access affect the productivity and profitability of GM maize cultivation. Challenges within the extension and advisory services of the Eastern Cape which can militate against smallholder farmers‟ ability to benefit from GM maize technology and sustain the long-term efficacy of the technology were identified during this study. Given these challenges and the fact that the cultivation of GM maize may not be profitable under typical smallholder maize cultivation conditions and management practices, dissemination approaches that provide farmers the opportunity to evaluate GM maize technology alongside alternate technologies under their conditions, may prove beneficial.
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2

Beyers, Andrea. "Ecological principles for honeybush (Cyclopia spp.) conservation and cultivation." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/5723.

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Market demand for the fynbos-derived honeybush (Cyclopia spp.) tea is on the rise, and there is an urgent need for better conservation of wild Cyclopia populations and for a shift to sustainable cultivation. Rooibos is another popular fynbos product that underwent exponential market growth over the last two decades but this resulted in large-scale conversion of pristine mountain fynbos to intensively-used crop lands. Adopting a conservation agriculture approach in expanding indigenous products will help in conserving biodiversity and ecosystem processes in this global biodiversity hotspot. Conservation agriculture of indigenous fynbos products grown in the Cape Floristic Region (CFR) should follow five main principles in order to maximise biodiversity conservation alongside agriculture. These principles are: 1) maintain high diversity at all levels, 2) conserve soil structure and processes, 3) conserve and restore natural ecosystem processes, 4) promote ecosystem stability and self-perpetuation, and 5) maintain natural areas as sources of ecosystem components. Given the negative ecological consequences of the industrialisation of the rooibos industry, it would be in the interest of biodiversity conservation, and even of agriculture, to apply these principles to honeybush cultivation. In order to prevent further fynbos habitat loss, cultivation of honeybush could be catalysed on old fields rather than in ploughed or cleared fynbos. Here I compare germination, growth and survival of two species (Cyclopia intermedia E.Mey. and C. subternata Vogel) between different land use types (ploughed lands, old fields and intact fynbos) and treatments (cleared and uncleared) in the Langkloof, Eastern Cape, over one year. Plots of each land use type were subject to each of these two treatments, although the ploughed plot constituted only a cleared treatment. Growth was highest on ploughed land, while survival and growth were lowest in uncleared fynbos. Cleared fynbos had the lowest germination success in both species, with the other sites and treatments coming out roughly the same. These results show that although ploughed lands give highest yields, growth and survival on old fields without ploughing is comparable with that on ploughed lands and is therefore a feasible alternative. Understanding the recruitment dynamics of honeybush is imperative for adequate conservation of wild populations. Furthermore, understanding this ecological aspect of the genus will help in developing the honeybush industry as a sustainable, agroecological market that uses semi-natural populations for production. Although Cyclopia species are early-successional species that germinate after fire, recruitment of Cyclopia pubescens Eckl. & Zeyh. continues throughout the inter-fire period. Cyclopia pubescens populations near Port Elizabeth were described according to their age structure and plant densities to discern possible density-dependent recruitment effects. Results showed that dense stands for the most part do not support high post-fire recruitment. This gives insight into suitable planting densities for new or restore populations and into management guidelines for remnant populations of threatened species. This thesis highlights important issues facing the honeybush industry. Mainstreaming biodiversity conservation into honeybush production is achievable, given that the industry is still relatively young, but this will require further research and strong market leadership.
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3

Steyn, Paul-Pierre. "The ecophysiology of Gelidium Pristoides (Turner) Kuetzing : towards commercial cultivation." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1117.

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The ecophysiology of the red alga Gelidium pristoides (Turner) Kuetzing was investigated in an effort to establish a technique for commercial cultivation. The seaweed is of commercial importance in South Africa where it is harvested from the intertidal zone rocky shores along the coast. It is dried and exported abroad for the extraction of agar. Yields and quality could be improved by cultivation in commercial systems. However, attempts at growing the seaweed in experimental systems have all ended in failure. This study aimed to describe the conditions in which the seaweed grows naturally; and investigate its physiological response to selected physical conditions in the laboratory in order to determine suitable conditions for mariculture. Ecological studies showed that G. pristoides grew above the spring low tide water level. The upper limit of the seaweed’s vertical distribution range, as well as its abundance, was largely dependent on wave exposure. The zone normally inhabited by G. pristoides was dominated by coralline turf in sheltered areas, while the abundance of G. pristoides increased towards more exposed rocky shore sites. The seaweed occurred among species such as Pattelid limpets and barnacles, but was usually the dominant macroalga in this zone, with coralline turf and encrusting algae being the only others. Physical conditions in the part of the intertidal zone inhabited by G. pristoides were highly variable. During low tide temperatures could vary by as much as 10°C within the three hours between tidal inundation of the seaweed population, while salinity varied by up to 9 ppt, and light intensity by as much as 800 μmol m-2 s-1. During these exposure periods the seaweed suffered up to 20% moisture loss. Laboratory experiments on the seaweed’s response to these conditions indicated that it was well adapted to such fluctuations. It had a broad salinity (20 and 40 ppt), and temperature tolerance range (18 to 24°C), with an o ptimum of temperature of 21°C for photosynthesis, while there was no difference in the photosynthetic rate of the alga within the 20 to 40 ppt salinity range. The alga had a low saturating irradiance (ca. 45 – 80 μmol m-2 s-1) equipping it well for photosynthesis in turbulent environments, with high light attenuation, but poorly to unattenuated light conditions. Exposure resulted in an initial increase in photosynthetic rate followed by a gradual decrease thereafter. pH drift experiments showed that low seawater pH, and associated increased carbon dioxide availability, resulted in an increase in photosynthetic rate. This response suggests that the seaweed has a high affinity for carbon dioxide, while the reduction in photosynthetic rate in response to bicarbonate use inhibition indicates that it also has the capacity for bicarbonate use. The high affinity of Gelidium pristoides for carbon dioxide as an inorganic carbon source appears to be the primary reason for the low abundance of the alga on sheltered rocky shore areas, and also explains the failure of the alga to grow in tank or open-water mariculture systems. Exposed rocky shores have experience heavy wave action, and the resultant aeration and mixing of nearshore waters increases the availability of carbon dioxide, which is considered a limiting resource. The absence of such mixing and aeration at sheltered site makes this less suitable habitat for G. pristoides. Periodic exposure also makes high levels of atmospheric carbon dioxide available from which the seaweed benefits. The traditional mariculture systems in which attempts have been made to cultivate the seaweed failed to satisfy either of the above conditions.
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4

Krugel, Louisa Jacoba. "White maize futures contracts in South Africa / Louisa Jacoba Krugel." Thesis, North-West University, 2003. http://hdl.handle.net/10394/340.

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Produsente van landboukommoditeite, veral in ontwikkelende lande, word blootgestel aan prysrisiko's. Markte vir landboukommoditeite in Suid-Afrika, soos in die res van die wêreld, is die afgelope aantal jare gekenmerk deur prosesse van deregulering. Die bemarkingsrade wat aanvanklik verantwoordelik was vir die bemarking van landbouprodukte, het ontbind en produsente van landbouprodukte moes nuwe metodes vind om hulle produkte te bemark. Een van die metodes wat gebruik word, is termynkontrakte. Witmielies en geelmielies is die twee landboukommoditeite wat in die grootste hoeveelhede geproduseer word in Suid-Afrika. Witmielies en geelmielies word as twee afsonderlike kommoditeite verhandel op die termynbeurs. Witmielies word hoofsaaklik aangewend vir menslike verbruik en geelmielies vir dierevoer. Hierdie studie fokus hoofsaaklik op witmielies. Die prys van mielies word beïnvloed deur veranderinge in die vraag daarna en aanbod daarvan. Faktore wat die vraag en aanbod van mielies beïnvloed is, onder andere, oesskattings, reënval, die wisselkoers en die pryse van mielies op die buitelandse mark, veral die markte in die VSA. In Suid-Afrika vorm die invoerpariteit en uitvoerpariteit 'n band waarbinne die prys van mielies varieer. Die doel van hierdie studie is om 'n regressievergelyking te konstrueer ten einde prys van die witmielietermynkontrakte te verklaar. Die regressie-analise word deur middel van 'n foutherstellende model met outoregressiewe foutterme behartig. Die regressie-analise slaag daarin om die prys van witmielietermynkontrakte te verklaar.
Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2004.
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5

Khumalo, Teclah P. "Consumer acceptability and perceptions of maize meal in Giyani, South Africa." Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-06132008-123740.

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6

Brittle, Wendy. "The optimisation of laboratory cultivation in childhood mycobacterial disease in South Africa." Thesis, [S.l. : s.n.], 2009. http://dk.cput.ac.za/cgi/viewcontent.cgi?article=1071&context=td_cput.

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7

Vermeulen, Hester. "Genetically modified white maize in South Africa : consumer perceptions and market segmentation." Diss., Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-11222005-110807.

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8

Baloyi, Rebecca Tshilambilu. "Technical efficiency in maize production by small-scale farmers in Ga-Mothiba, Limpopo Province, South Africa." Thesis, University of Limpopo, 2011. http://hdl.handle.net/10386/1419.

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Thesis (M.Agric. (Agricultural Economics)) -- University of Limpopo
Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse environments. The study only focuses on the technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. Technical efficiency is the ability of a farmer to obtain output from a given set of physical inputs. Farmers have a tendency of under and/or overutilising the factors of production. The main aim of this study was to analyse the technical efficiency of small-scale maize producers in Ga-Mothiba rural community of Limpopo Province. The objective of the study was to determine the level of technical efficiency of smallscale maize producers and to identify the socio-economic characteristics that influence technical efficiency of small-scale maize producers in Ga-Mothiba. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. Cobb-Douglas production function was used to determine the level of technical efficiency and Logistic regression model was used to analyse the variables that have influence the technical efficiency of maize production. Cobb-Douglas results reveal that small-scale farmers in Ga-Mothiba are experiencing technical inefficiency in maize production due to the decreasing return to scale, which means they are over-utilising factors of production. Logistic regression results indicate that out of 13 variables included in the analysis as socio-economic factors, 10 of them (level of education, income of the household on monthly basis, farmer`s farming experience, farm size, cost of tractor hours, fertiliser application, purchased hybrid maize seeds, membership to farmers` organisation, is maize profitable) were found to be significant and 3 (gender, age and hired labour) are non-significant. However, farm size was found to be the most significant variable at 99% level, showing a positive relationship to smallscale maize producer`s technical efficiency. Therefore, it is recommended that government should do the on-farm training since farmers mainly depend on trial and error and farmers` should have access to enough arable land and tractor services. However, farmers need to be trained on matters relating to fertiliser application, on the amount of seeds a farmer should apply per ha, and the importance of using hybrid seed.
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9

Boucher, Kim Gillian. "The effect of pineapple cultivation on factors influencing soil erodibility in the Eastern Cape, South Africa." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005502.

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The study examines the effect of ridged pineapple cultivation on factors influencing the soil erodibility of Glenrosa and Oakleaf soil forms in the Bathurst district of South Africa. A number of physical and chemical variables influencing soil erodibility are investigated, namely soil moisture, bulk density, porosity, infiltration rate, aggregate stability, shear strength, soil texture, soil structure, penetrability, organic carbon, pH and cation exchange capacity. These soil characteristics are examined in undisturbed soils under natural vegetation and compared to those on adjacent traffic areas, pineapple ridges and pineapple furrows. The results of the analyses between the four sample sites indicate that ridged cultivation of pineapples has a negative effect on factors influencing soil erodibility on the areas studied. The results of the analysis within each of the sample sites do not illustrate any clear relationships and thus depict the complexity and multiplicity of the soil erodibility phenomenon. A further study, augmenting the soil erodibility data with actual soil loss data, is recommended
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10

Sowunmi, Linda Ifeanyichukwu. "Nutritional value and cultivation requirements of Cleome Gynandra: a wild vegetable growing in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/2600.

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South Africa has wide ranges of plants among which are leafy vegetables growing in the wild. These wild vegetables have been reported to have high nutritive and medicinal potentials. Yet, there is still high prevalence of malnutrition and micronutrients deficiencies among the low income bracket of the population. Effective utilization of wild vegetables has been proposed as part of the solutions to address the problem of dietary deficiencies among the populace. Their importance is mainly as relish to accompany and complement starch based diets. They are also known to serve as supplements for food which have the potential to improve the health status of its consumers in many rural communities. Cleome gynandra L. (Capparaceae) is one of the underutilized species mentioned during asurvey conducted in Nkonkobe municipality of the Eastern Cape Province, South Africa. The plant is an erect annual herb with alternate, palmately compound leaves and its petals are white, pink or lilac. It grows as a weed in this part of the Province and is usually gathered from the wild for food and medicine. It is commonly found on wastes land, road sides and on grass lands. Therefore, this research work was designed to contribute to the possible domestication of this wild vegetable in order to explore the nutritive and therapeutic potentials which would broaden the food base in the Eastern Cape Province. The ultra-micromorphological features of plants have become an essential tool in proper identification and authentication of several plant species. In the light of this, the micromorphology of Cleome gynandra was examined to reveal the micro-morphological characters of the plantand to determine if micro and macro mineral elements are present using energy dispersive x-rays. The present study revealed the epidermal cells of the leaves to be asymmetric in shape with undulating cell walls having four subsidiary cells around the stomata. The leaves have anomocyctic stomata which are more distributed in the abaxial surface than the adaxial surface. The mean length and width of the guard cells in the abaxial surface are 0.09 ± 0.01 mm and 0.08 ± 0.01 mm respectively while that of adaxial surface are 0.1± 0.01 mm and 0.07 ± 0.01 mm respectively. The energy dispersive x-rays (EDXS) micro-analysis of the leaf revealed the presence of phosphorus, manganese, iron, calcium, sodium, magnesium, potassium and zinc as the major constituents of the crystal deposits present in the stomata pores and the mesophyll. C. gynandra was collected from the wild and analysed for its mineral and proximatecomposition using standard analytical methods. The plant showed high levels of sodium, iron, zinc, calcium and potassium while many other macro and micro minerals were moderately present. Amongst the proximate factors investigated, moisture content was found to be 82.1% while crude fibre and protein contents were 39.9 percent and 31.03 percent respectively. Vitamin C was also high (345.3 mg/100g). The anti-nutrients compositions revealed low concentrations of oxalate (7.4 ± 0.4) and phytate (0.6 ± 0.0) mg/100g. The study revealed high nutritive value of the species growing naturally from the wild. Interest in the phenolic compounds has greatly increased recently because these compounds have been implicated in suppressing the risk of degenerative diseases in humans. The pharmacological properties of plants may be related to their antioxidant capacities and hence there was need to investigate the antioxidant potential using aqueous, ethanolic and acetone extracts of different parts of C. gynandra. The quantities of phenols, flavonoids and flavonols were significantly higher (p < 0.05) in both aqueous and ethanol extracts of the leaf while the concentration of proanthocyanidins was higher in the aqueous stem extract compared to other plant parts. The aqueous extract of the different parts exhibited better ABTS, reducing power and NO radical scavenging abilities than ethanol extract.
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11

Le, Roux Noelien. "Seasonal maize yield simulations for South Africa using a multi-model esemble system." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-11302009-211655/.

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12

Grewar, Robert. "Investigating the relationship between sustainability and farmer decision-making: a qualitative study of maize farmers in Mpumalanga, South Africa." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1003906.

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The goal of the research paper was to understand the complex relationship between the issue of sustainability and maize farmers’ decision-making processes. The aim is to shed light on the realities experienced by maize farmers in terms of how sustainability impacts on the decisions they make and how the decisions they make impact on sustainability. The importance of the research lies in the current state of affairs in the world in terms of the current economic recession, overpopulation, dire poverty and hunger, and the poor state of the environment. If humankind is to continue its existence on Earth in a happy, healthy world, something is going to have to give. In order for this to happen, people need to start grappling with the concept of sustainability. Focusing on sustainability as a whole is likely to end in despair. However, breaking the problem down into its component pieces will allow people to influence the particular sector in which they operate. It is therefore imperative for research into sustainability to be undertaken in all sectors of society and the economy. Agriculture presents an excellent research area due to its intrinsic link with the environment, society and the economy. Agriculture and its wellbeing is inextricably tied to environmental health. Healthy plants and animals will not grow in unhealthy conditions. Society is to a large degree dependent on agriculture for food, agriculture therefore has a significant impact on social order and function. Agriculture is one of the primary contributors to GDP, particularly in poor and developing nations. As a result, agriculture has an important role to play in ensuring economic sustainability. In order to engage with sustainability from an agricultural perspective it was decided to engage on the farmer-level. Gaining an understanding of their reality in terms of what motivates their decisions is key to understanding the relationship between agriculture and sustainability. Three maize farmers in Mpumalanga, South Africa, were interviewed with the aim of collecting qualitative data and then analysing the data using thematic analysis. The methodology employed enabled the researcher to uncover patterns in the data that constituted themes across the interviews. The following themes emerged: Theme 1: Economic factors are the primary decision driver. This is primarily due to the extent of the financial risk experienced by farmers as a result of market risk, production risk, finance risk, and rising input costs. This results in economic considerations superseding environmental or social concerns in farmers’ decisions. This has a negative impact on the overall sustainability of the farming operation. Theme 2: There has been a decrease in the number of family-run farms. This is attributable to a number of factors including economic failure, fear of loss of land due to land-reform policies, as well as crime. Family-run farms tend to have a greater focus on sustainability due to the vested interest in the next generation taking over the farm. The corporate farming operations that are taking over the farms tend to be more focussed on short-term gains in order to satisfy shareholders. Theme 3: Mechanisation is preferable to manual labour. There has been an alarming decrease in the number of labourers employed on farms. Farmers say this is due to two factors. Firstly, machines are more efficient than labour. Secondly, restrictive labour laws have made famers less keen to employ people. The net effect of these two factors is that unemployment is rising. This has negative consequences for society, the economy, and the environment. Theme 4: Farmers believe they do very little environmental damage. This results in decisions being made that do not consider environmental wellbeing other than soil health. This is because farmers see healthy soil as an integral input that optimises economic performance. Farmers tend to prioritise economic factors in their decisions more than environmental or social factors. This results in an unsustainable perspective. The only ways in which this is likely to change is if the financial risk associated with agriculture is decreased, or if farmers are given financial incentive to change their ways. In order to deal with this issue it is necessary for further research to be conducted. Research needs to be conducted to confirm the results of this study. It is important to know whether the results pertain only to maize farmers in Mpumalanga or whether most farmers in South Africa, and indeed the world, face similar problems. Research should also be conducted to propose policies or procedures to reduce financial risk in agriculture. Research should focus on reducing market risk and reducing input costs, possibly via subsidisation.
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13

Cass, Lionel. "Maize marketing strategies : the trade-off between risk and profit for a Mpumalanga maize farm." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/27205.

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South Africa has become, after deregulation, part of the global village. This brought about many business opportunities, but with it came many challenges with respect to grain marketing. It is well-known facts that the marketing of grain has become quite a challenge in S.A. South African producers do not receive support from government as far as input subsidies and significant import tariffs are concerned and have to make sure that they stay ahead of rising input costs in order to produce maize on a profitable basis. It is therefore extremely important for any maize farmer in South Africa to make use of the best grain marketing strategies at his or her disposal. Choosing the best grain marketing strategy will not only assist the producers to receive the best price for their produce, but will also serve as a very effective risk mitigation strategy. The general objective of the study is to examine different marketing strategies and to determine the optimal maize marketing strategy for a representative farm located in the Mpumalanga Highveld for a specific season under volatile marketing and environmental conditions. A representative farm for the Mpumalanga Highveld is constructed, based on production data, budgeted financial statements, general financial management and the complete farm setup as obtained from a farmer study group located in the district of Middelburg, Mpumalanga Highveld, The most general maize marketing strategies available for the representative farm is identified and discussed as far as each of their advantages and disadvantages are concerned. The complete farm setup for the representative farm is used to develop a budgeting and maize marketing model. This is done in conjunction with three different scenarios, which cover the most frequent circumstances in which producers can find themselves. With the help of this model, the optimal marketing strategies are determined which yields the optimal profit and minimize price risk for the representative farm. Copyright
Dissertation (MSc(Agric))--University of Pretoria, 2009.
Agricultural Economics, Extension and Rural Development
unrestricted
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Muzangwa, Lindah. "Cover crop biomass production and effects on weeds and soil fertility in a maize-based conservation agriculture system." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/484.

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Low cover crop biomass production is a major obstacle to the success of conservation agriculture currently promoted as panacea to the inherent problem of soil erosion and loss of soil productivity in the Eastern Cape (EC). Therefore, this study evaluated cover crop management strategies for optimizing biomass production for better soil cover, soil nitrogen (N) and phosphorus (P) fertility, weed control and maize yields. The strategies tested are cover crop bicultures, selection of an adapted lupin cultivar and seeding rate, and the feasibility of rain fed winter cover cropping. The cover crop experiments were carried in rotation with summer maize between the winter of 2009 and summer of 2010/2011. Biculture trial was carried out by seeding oat (Avena sativa) and vetch (Vicia dasycarpa) at three mixture ratios and as sole crops under irrigation. On a separate irrigated trial, two lupin cultivars (Lupinus angustifolius var Mandelup & Qualinock) were seeded to a range of seeding rate, 40 to 220 kg ha-1. To study the feasibility of rain fed winter cover cropping, oat, vetch, rye (Lolium multiflorum), barley (Hordeum vulgare), radish (Raphanus sativa) and triticale (Triticale secale) were relayed into a maize crop in February, March and April of 2010. The irrigated trials were followed with SC701 maize cultivar, whilst the rain fed trial was followed with DKC61-25 maize cultivar. Bicultures gave higher cover crop biomass than sole vetch, increasing with an increase in the oat component of the mixture. Increased N and P uptake was observed with bicultures compared to sole oat, however, the levels were comparable to sole vetch. Sole vetch increased soil inorganic N and P at maize planting, whilst the slow decomposition by sole oat residue resulted in mineral lock up. Bicultured cover crop residues had intermediate decomposition rates and resulted in optimum levels of inorganic N and P for prolonged periods compared to sole crops. Weed suppression by the bicultures was comparable to sole cover crops. Biculturing technology significantly (P<0.05) increased maize grain yield compared to sole oat and the yields were comparable to those from sole vetch. For lupins, 206 kg ha-1 seeding rate gave the optimum biomass yield. Weed dry weights in both cover crop and maize crop decreased with an increase in lupin biomass. Comparable soil total N and inorganic P values at maize planting, were observed from plots planted to 120, 180 and 220 kg ha-1. Maize grain yield increased with an increase in lupin seeding rate. The study on rain fed winter cover cropping had most cover crop species’ biomass decreasing with each delay in planting except for radish, which increased. Vetch produced the highest amounts of biomass from February and March planting whilst radish had the highest biomass in April planting. The two species resulted in the greatest N improvement compared to the other species. Regardless of the grazing, the grass specie residues managed to persist to the next cropping season and the residue remaining were comparable to that of radish and vetch. Late-planted cover crops had the greatest residue remaining than early-planted, as a result, April planted cover crops provided better weed suppression than March and April planted. Vetch provided the highest maize grain yield (4005 kg ha-1) whilst all other species tested had comparable grain yields. The results suggested that bicultures could be grown to give sufficient biomass for both weed suppression and soil fertility improvement. Furthermore, increasing lupin plant densities improve its function as a cover crop with respect to weed suppression, soil fertility improvement and maize yields. The study also showed that for dry land systems, February and March planted vetch and April planted radish can provide the greatest biomass and maize yield improvement.
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Mandikiana, Brian Washington. "The economics of Bt maize/yieldgard production: case of smallholder farmers in the Eastern Cape Province." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/326.

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Maize is the staple food for most South Africans. This implies that any damage to the maize crop will affect food security of many South Africans. Although Eastern Cape Province is not a traditionally maize producing area, smallholder farmers in the province produce it mostly for subsistence purposes and some sell the surplus on the local market or use it to secure other good through barter trading. In South Africa, insect-resistant Bt maize/yieldgard has been used commercially for approximately 10 years now. Available impact studies on Bt maize reveal that, this technology is beneficial not only to farmers but consumers of maize products as well. Welfare gains as well as positive effects for human health are realised by both groups. Due to the costs and effectiveness associated with traditional and conventional maize stem borer control methods, Bt technology has the potential to be part of the solution. This thesis has attempted to investigate the economic viability of planting Bt maize seeds under smallholder farming conditions and identify factors as well as perceptions relating to attributes of Bt maize and to analyze the relationships between those perceptions and choices regarding use of Bt technology. Data was collected from 90 households who were selected using purposive sampling through the use of the snowball method. To collect data, a questionnaire was administered through face-to-face interviews. Gross margin analysis revealed that Bt maize is a more profitable option as compared to conventional maize seeds. Furthermore, econometric analyses, through use of the binomial regression model revealed that perceptions could be used to distinguish between users and non-users of Bt maize seed in the Eastern Cape Province. Results of inferential analysis indicate that the statistically significant variables at 5% level are gene erosion, quality and nutrition of products and food labels for Bt maize products perceptions. On the other hand, low expenses, seed market availability and farmers’ knowledge perceptions were significant at 10%. These findings suggest that an adjustment in each one of the significant variables can significantly influence the probability of Bt maize adoption. In view of the research findings, several policy proposals are suggested to support policy formulation. Key words: Bacillus thuringiensis (Bt) maize, yieldgard, smallholder farmers, perceptions, Flagstaff, gross margin analysis, binomial logistic regression model, Eastern Cape Province.
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16

Manes, Rebecca. "Determinants of adoption of genetically modified maize by smallholders in KwaZulu-Natal, South Africa." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15706.

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Master of Science
Department of Agricultural Economics
Timothy Dalton
Previous research on small-scale farmers in KwaZulu-Natal, South Africa indicates that certain genetically modified maize seed types improve production efficiencies and increase net returns (Regier 2012). Yet despite the substantiated advantages, not all farmers have adopted genetically modified maize. The purpose of this research is to identify the determinants of adopting certain types of genetically modified maize over traditional or conventional hybrid maize for 184 small-holders in two villages in KwaZulu-Natal, South Africa. Previous adoption studies use socioeconomic characteristics of the farmer as well as farm-level production characteristics to determine the probability that a farmer will implement an improved agricultural technology. While many studies employ a binomial approach to adoption, this study tests the probability of adopting three different GM varieties—the insect resistant Bt maize, the herbicide tolerant Roundup Ready® maize, and the stacked trait BR maize. Furthermore, the model is enhanced by farmers’ open-ended explanations of their perceptions on genetically modified maize and of the major production constraints they face. Following results from previous adoption studies, this research tests three hypotheses in a three different model structures. The first hypothesis tests whether farmers are more likely to adopt if they have greater financial means to cover higher expected production costs. This is tested by variables measuring off-farm employment and expected production costs. The second hypothesis tests whether farmers with less labor availability are more likely to choose maize with the herbicide tolerant technology, either the Roundup Ready® or stacked BR maize, which reduce the need for weeding. The final hypothesis is whether there are differences in the determinants of adoption that differentiate GM adopters into three distinct categories. These hypotheses are tested in three model structures that test the binary probability of adopting GM maize over non-GM, the probabilities of adopting each maize variety separately, and the intensity of adoption. The first finding is that many non-adopters have greater access to income and are more likely to sell a portion of their yield than are many farmers who adopted, especially in comparison to those who plant RR maize. Also, BR farmers are more likely to report input expenses as a major constraint in their adoption decision. Results for the second hypothesis show that those who planted either RR or BR maize did in fact have less family labor available, used less total labor, and used a greater proportion of family to hired labor. Finally, there are differences in the determinants for geographic site, education, self-sufficiency in maize supply, number of family members working off-farm, and whether households planned to sell any of their maize yields. This indicates that adoption should be considered according to each genetically modified trait.
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17

Puta, Usanda. "Effects of genetically modified maize (MON810) and its residues on the functional diversity of microorganisms in two South African soils." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/419.

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Genetically modified (GM) crops are commercially cultivated worldwide but there are concerns on their possible negative impacts on soil biodiversity. A glasshouse study was conducted to determine effects of Bt maize residues on soil microbial diversity. Residues of Bt maize (PAN 6Q-308B) and non-Bt maize (PAN 6Q-121) were incorporated into the soil and corresponding maize seeds planted. The treatments were replicated three times. Fertilizer and water application were similar for both treatments. Rhizosphere and bulk soil was destructively sampled from each treatment and analyzed for microbial community level physiological profiles using Biolog plates with 31 different carbon substrates. Absorbance in the Biolog plates was recorded after 72 h of incubation at 20oC. Arbuscular mycorrhizal fungi spore counts were also determined. Field studies were conducted at the University of Free State and University of Fort Hare Research Farms to determine the effects of growing Bt maize on soil microbial diversity. One Bt maize cultivar (PAN6Q-308B) and non-Bt maize (PAN6Q-121) were grown in a paired experiment at University of Free State farm, while two Bt maize (DKC61-25B and PAN6Q-321B) and their near-isogenic non-Bt maize lines (DKC61-24 and PAN6777) were grown in a randomized complete block design with three replicates. Fertilization, weed control and water application, were similar for both Bt maize cultivars and their non-Bt maize counterparts. Rhizosphere soil samples were collected by uprooting whole plants and collecting the soil attached to the roots. The samples were analysed for microbial diversity and for arbuscular mycorrhizae fungal spore counts. Principal component analysis showed that soil microbial diversity was affected more by sampling time whereas genetic modification had minimal effects. Presence of residues also increased the diversity of microorganisms. Mycorrhizal fungal spores were not affected by the presence of Bt maize residues. Growing Bt maize had no effect on the soil microbial diversity in the rhizosphere.
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18

O'Kennedy, Kim. "Characterisation of zein from South African maize of varying endosperm texture." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6784.

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Thesis (MSc Food Sc)--University of Stellenbosch, 2011.
Includes bibliography.
ENGLISH ABSTRACT: Maize is an important crop for both human and animal consumption. Maize kernel texture (kernel hardness) is an important quality trait for many sectors in the South African maize industry, where a harder texture is desired. Both total protein content and the main storage proteins, zein, have been associated with kernel texture. The zein profiles of South African white maize hybrids, from a breeding program, grown at three localities together with their respective inbred parent lines were evaluated to determine the difference in zein expression. For only the hybrids, total protein content, zein content and degree of hardness (kernel texture) was determined to establish possible relationships. Zein consists of four main classes, α-, β-, γ-, and δ-zein, which can further be divided into sub-classes. Zein was characterised using matrix-assisted laser desorption ionisation time-offlight mass spectrometry (MALDI-TOF MS) after optimisation of the zein extraction and matrix preparation procedures. Two matrices [2-(4-hydroxyphenylazo)benzoic acid (HABA) and α- cyano-4-hydroxy-cinammic acid (CHCA)] and three pH levels (<1.5, 1.7 and 2.9) for matrix solutions were investigated. Two solvent concentrations (50% and 70% acetonitrile (ACN) were also investigated. Parallel to this investigation, a zein extraction procedure was optimised. Zein was extracted from non-defatted (NDF) and defatted (DF) maize meal at ambient temperature and 60°C and meal with different particle size distributions. Particle size of maize meal did not influence the quality of spectra. Regardless of matrix conditions used, zein extracted at 60°C from NDF meal produced spectra with a low signal-to-noise (S/N) ratio. When only HABA was included (pH<1.5), not all γ-zein sub-classes were observed. This was also true for zein extracted at ambient temperature from NDF and DF meal. Good S/N ratios for all zein classes were obtained when zein was extracted from NDF meal at ambient temperature using a matrix solution containing both matrices in 70% ACN at pH 2.9. MALDI-TOF MS provided accurate detection and good profile resolution for zein characterisation. Spectral profiles of hybrids were a combination of their respective inbred parent lines. Zein proteins were quantified using reverse-phase high performance liquid chromatography (RP-HPLC). Total protein content was determined and kernel texture assessed using a particle size (PSI) method. Significant (P<0.01) differences were observed for total protein content and degree of hardness between certain hybrids as well as average values for localities. Correlations and principal component analysis indicated that hybrids with a higher protein and total zein content had a harder kernel texture. The β- and γ-zein contents also correlated positively with kernel hardness. However, when expressed as percentage of total zein the opposite was observed. Collectively the α-zeins and most individual α-zeins correlated positively with hardness. Scanning electron microscopy micrographs showed differences between the floury endosperm of harder and softer maize kernels; illustrating starch types (amylose and amylopectin) should also be analysed in future hardness studies. The correlations obtained were not strong (r<0.6) and the variation explained by first two principal components was low. Other maize constituents, more hardness measurements should be considered in future studies to improve this.
AFRIKAANSE OPSOMMING: Mielies is a belangrike gewas vir beide mens- en dierlike inname. Mieliepittekstuur (pithardheid) is ‘n belangrike kwaliteitseienskap vir baie sektore in die Suid Afrikaanse mielieindustrie, waar ‘n harder tekstuur verlang word. Beide totale proteïeninhoud en die hoof opbergingsproteïen, zein, is al geassosieer met pittekstuur. Die zein profiele van Suid- Afrikaanse witmielie basters, van ‘n teel program, wat by drie lokaliteite verbou is sowel as hul onderskeie ingeteelde ouerlyne is geevalueer om verskille in zein uitdrukking te bepaal. Die totale proteïeninhoud, zeininhoud en graad van hardheid is bepaal om verhoudings vas te stel. Zein bestaan uit vier hoof klasse, α-, β-, γ-, en δ-zein, wat verder onderverdeel word in subklasse. Zein is gekarakteriseer met matriks-ondersteunende laser desorpsie ionisasie tyd-vanvlug massa spektrometrie (MBLDI-TVV MS) na die zein ekstraksie en matriks voorbereidingprosedures geoptimaliseer is. Twee matrikse [2-(4-hydroksiephenylazo)benzoë suur (HABA) en α-cyano-4-hydroksie-kaneelsuur (CHCA)] en drie pH vlakke (<1.5, 1.7 and 2.9) vir matriksoplossings was ondersoek. Twee oplossingkonsentrasies [50% and 70% asetonitriel (ACN)] is ook ondersoek. Zein ekstraksie kondisies is ook geoptimiseer. Zein is geëkstraheer van nie-ontvette (NOV) en ontvette (OV) mieliemeel by omgewings temperatuur en 60°C. Die partikelgrootte van die mieliemeel het nie die kwaliteit van spektra beïnvloed nie. Ongeag watter matrikskondisies gebruik is het zein wat van NGV meel by 60°C ge-ekstraheer is, spektra met ‘n lae sein-tot-geraas (S/G) verhouding geproduseer. As die HABA alleenlik gebruik (by pH<1.5) is, is nie alle γ-zein klasse waargeneem nie. Dit was ook waar vir zein wat by omgewings temperatuur van NGV en OV mieliemeel ge-ekstraheer is. Goeie S/G verhoudings is waargeneem met zein, ge-ekstraheer van NGV mieliemeel by omringende temperatuur, met die bebruik van beide matrikse in 70% ACN by pH 2.9. (MBLDI-TVV MS) het akkurate en goeie resolusie van profiele vir zein karateriseering verksaf. Spektrale profiele van basters was ’n kombinasie van hul onderskeie ouer lyne. Zeinproteïene is met omgekeerde-fase hoë prestasie vloeistofchromatografie gekwantifiseer. Totale proteïeninhoud is bepaal en die hardheidsgraad was bepaal met ‘n partikelgroote indeks (PGI) metode. Beduidende verskille tussen proteïeninhoud en hardheidsgraad is waargeneem tussen sekere basters sowel as gemiddelde waardes by die verskeie lokalieteite. Korrelasies en hoofkomponent analise het aangedui dat basters met ‘n hoër proteïeninhoud en totale zein ‘n harder tekstuur gehad het. Die β- en γ-zeininhoud het ook positief gekorreleer met hardheid. Alhoewel, wanneer die proteïene as persentasie van totale zein uitgedruk is, is die teenoorgestelde waargeneem. Gesamentelik het α-zein asook die meeste indivduele α-zeins positief gekorreleer met hardheid. Skandeer elektron mikroskopie mikrograwe het verskille tussen die meelerige endosperm van harder en sagter pitte aangedui; meer proteïenliggame was aanwesig in die harder pitte en die stysel was digter gepak. Dus moet stysel tipes ook in ag geneem word in toekomstige hardheidsstudies. Korrelasies wat verkry is, was nie hoog (r<0.6) nie en die variasie verduidelik deur die eerste twee hoofkomponente was laag. Ander miielie samestellende dele as ook meer hardheidsmetings moet in toekomstige studies in ag geneem word om dit te verbeter.
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19

Mofokeng, Maine Jonas. "Factors affecting the hedging decision of farmers : the case of maize farmers in Gauteng province." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71750.

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Thesis (MScAgric)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Maize is the most important field crop in South Africa. It is used for both animal feeds and human consumption. It is also used by many industries as an input, is a source of foreign exchange and of employment opportunities for many people in the country. It is an important component of the agricultural sector, plays an important role in the economy and presents opportunities in terms of agricultural investment and employment creation. The maize industry in South Africa has long history of government intervention where the price of maize was set by government through the office of the Minister of Agriculture. This was fuelled by the two Marketing Acts (of 1937 and 1968). During the period of these Acts, farmers were not exposed to international markets. However after the introduction of the Marketing of Agricultural Products Act (Act 47 of 1996), farmers have been exposed to international maize prices, i.e. to the forces of supply and demand. Farmers are no longer guaranteed a maize price during the beginning of the production season, and now have to use different methods to protect their income against a volatile maize price. Through forward contracting (hedging) their maize, farmers can minimize the price risk that they are facing. A number of instruments have been developed to assist farmers to protect themselves against price risk. In South Africa, SAFEX is used to reflect the expected future price of maize and it can be used by farmers as a reference for the expected price. Different factors affect the hedging decisions of farmers. The main objective of this study was to identify factors affecting the hedging decision of maize farmers in Gauteng, and hence their rate of adoption of hedging strategies. The study employed a number of methods in an effort to answer this question. Data analysis relating to factors affecting the hedging decision of the farmers was carried out using Excel and the SPSS statistical package and took the form of multiple cross tabulation. A Probit regression equation was estimated using the SPSS 20 statistical software package. In the case of the adoption rate of hedging by maize farmers in Gauteng, it was found that only 35 per cent of the maize farmers forward contract their maize against price risk. This implies that they are not protecting their income against price volatility through forward contracting. The results show that the factors that have the most influence on the decision whether to hedge are: the gender, age, and agricultural qualification of the principal decision maker; whether the decision maker is a member of a grain association and the size of that grain association; the length of period that the decision maker has been producing grain; the size of the farm; whether the farmer rents in land; the proportion of off-farm income earned and whether the farmer takes out insurance. These variables are all statistically significant at the 5 per cent level.
AFRIKAANSE OPSOMMING: Mielies is die belangrikste akkerbougewas in Suid-Afrika. Dit word gebruik vir beide dierevoere en menslike verbruik. Dit word ook in baie bedrywe as ’n inset gebruik, vorm ’n bron van buitelandse valuta en verskaf werksgeleenthede aan baie mense in die land. Dit is ’n belangrike komponent van die landbousektor, speel ’n belangrike rol in die ekonomie en verskaf geleenthede in terme van landboubelegging en werkskepping. Die mieliebedryf in Suid-Afrika het ’n lang geskiedenis van regeringsingryping waardeur die prys van mielies deur die regering, by name van die kantoor van die Minister van Landbou, vasgestel is. Dit is aangevuur deur twee Bemarkingswette (van 1937 en 1968). Gedurende die tydperk van hierdie wette is boere nie aan internasionale markte blootgestel nie. Met die aanvang van die Wet op die Bemarking van Landbouprodukte (Wet 47 van 1996) is boere aan internasionale mieliepryse blootgestel, m.a.w. aan die kragte van vraag en aanbod. Boere word nie meer aan die begin van die produksieseisoen ’n mielieprys gewaarborg nie, en moet nou ander maniere vind om hulle inkomste teen ’n onbestendige mielieprys te beskerm. Deur die koop van termynkontrakte op hulle mielies (verskansing) kan boere die prysrisiko’s wat hulle in die gesig staar, minimaliseer. ’n Aantal instrumente is ontwikkel om boere te help om hulleself teen prysrisiko te beskerm. In Suid-Afrika word SAFEX gebruik om die verwagte toekomstige prys van mielies te weerspieël en dit kan deur boere as ’n verwysing na die verwagte prys gebruik word. Verskeie faktore beïnvloed die verskansingsbesluite van boere. Die belangrikste doelwit van hierdie studie was om faktore te identifiseer wat die verskansingsbesluit van mielieboere in Gauteng beïnvloed, en dus die tempo waarteen hulle verskansingstrategieë in gebruik neem. Die studie het ’n aantal metodes gebruik in ’n poging om hierdie vraag te beantwoord. Data-analise m.b.t. die faktore wat die verskansingsbesluit van die boere beïnvloed, is met Excel en die SPSS statistiese pakket uitgevoer en het die vorm van meervoudige kruistabellering aangeneem. ’n Probitregressievergelyking is met behulp van SPSS 20 statistiese sagteware beraam. In die geval van die tempo van aanneming van verskansing deur mielieboere in Gauteng is daar gevind dat net 35 persent van die mielieboere termynkontrakte op hulle mielies gebruik om hulle teen prysrisiko te beskerm. Dit impliseer dat hulle nie hulle inkomste teen onbestendige pryse beskerm nie. Die resultate toon dat die faktore wat die grootste invloed het op die besluit om te verskans die volgende is: die geslag, ouderdom en landboukwalifikasie van die hoof besluitnemer; of die besluitnemer ’n lid van ’n graanvereniging is, en die grootte van dié graanvereniging; hoe lank die besluitnemer reeds graan produseer; die grootte van die plaas; of die boer grond inhuur; die proporsie van inkomste wat weg van die plaas af verdien word; en of die boer versekering uitneem. Hierdie veranderlikes is almal statisties betekenisvol by die 5 persent vlak.
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20

White, Andrew Graeme. "The effect of geography, cultivation and harvest technique on the umckalin concentration and growth of pelargonium sidoides (Geraniaceae)." Thesis, Rhodes University, 2007. http://hdl.handle.net/10962/d1003803.

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Pelargonium sidoides DC. (Geraniaceae) root extracts are used in the Eastern Cape Province of South Africa as a traditional medicine for the treatment of respiratory tract and gastro-intestinal infections. Ethanolic extracts are used globally as herbal treatments for bronchitis, asthma and as an immune system booster. Despite documented exploitation of wild populations by illegal harvesters, this species has not been awarded a protected status. The high level of harvest in the years preceding this study prompted this investigation of the prospects for sustainable root harvest through wild harvest and greenhouse cultivation. A novel method was developed for the purification of umckalin, a bioactive constituent in root extracts, such that the root umckalin concentrations of wild and cultivated plants could be quantified by HPLC. As part of the cultivation experiments, the concentration of umckalin in roots was measured for plants across part of the species’ distribution range in the Eastern Cape Province. This survey revealed that root umckalin concentrations were inversely related to the average annual rainfall of the collection site (r² = 0.94, p = 0.007) and directly related to soil pH (r² = 0.97, p = 0.002). Thus, the possibility of inducing high umckalin concentrations in greenhouse-cultivated plants was investigated by subjecting plants to rapid and prolonged water stress treatments. Two leaf applied hormone treatments (cytokinin and gibberellin) and a root competition treatment with a fast growing annual (Conyza albida) were also investigated based on the potential function of umckalin in P. sidoides plants. These five treatments did not significantly affect root umckalin concentrations compared to well-watered controls. The results of further experiments suggested that umckalin production may have been influenced by the geographical origin and genetics of plants rather than environmental variation. Following wild harvest experiments, the regrowth of replanted shoots from which a standard proportion of the root was harvested showed that water availability affected shoot survival but not root regrowth rate. Regrowth rates were low, questioning the viability of wild harvest. In contrast, greenhouse cultivated plants showed ca. six times greater growth rates, supporting the cultivation of roots to supply future market demand.
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21

Tafa, Sanelise. "Farm level cost-benefit analysis of conservation agriculture for maize smallholder farners in Okhahlamba Municipality in Kwa-Zulu Natal Province, South Africa." Thesis, University of Fort Hare, 2017. http://hdl.handle.net/10353/2809.

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Land degradation is a serious problem that many poor communities face and this worsens their vulnerability and therefore, poses a threat to food security, as it reduces yield, forces farmers to use more inputs, and disproportionately affect the smallholder farmers in remote communities that also suffer diverse infrastructure disadvantages. In response to that, the international development agencies, donors, and Non-Governmental Organizations (NGOs), especially faith-based organizations have turned towards sustainable farming approaches. Much attention has been paid to a combination of sustainable farming measures which are packaged under the “Conservation Agriculture” (CA) banner. The previous work in the KZN Province and elsewhere has demonstrated that CA has the potential to improve the soil structure, thereby reversing the effect of soil degradation. Consequently, many of the farmers in the areas in which these demonstrations have been conducted appreciate the ecological and economic value of adopting CA. However, the on-farm financial benefits of adopting a CA specific tillage practice are not as well known or thought to be as pronounced. By means of integrating field survey, reviewed literature, and econometric analysis, this study assessed the farm level cost-benefit analysis of conservation agriculture for smallholder maize farmers in OLM, specifically in one demonstration village of Bergville town. The analysis is based on the case study of the NGO’s work in which they had selected a community and participating households who received assistance in a number of ways such as maize seed, soil preparation, and CA planters. To analyse the farm level cost-benefit analysis, descriptive, linear regression, gross margin (GM) and appraisal indicators such as Net Present Value (NPV), Benefit Cost Ratio (BCR) and Internal Rate of Return (IRR) were used. The descriptive analysis, used to analyse the factors affecting the extent of adoption of CA revealed that socio-economic characteristics have the influence on the level to which a farmer responds to incentives. Linear regression model used in this study showed that years in farming, involvement in joint farmer’s group, and use of cover crops have the significant effect on the extent of adoption of CA. Moreover, the calculated gross margins of the two tillage systems were different, revealing higher Gross Margins for CA plots than for conventional plots. The major cause of the difference was found to be differences in the variable costs. When using appraisal indicators (NPV, BCR, and IRR) the study projected a 10-year period at 8% and 10.5% discount rates. The study also revealed positive NPVs for both CA and conventional agriculture. The positive sign implies that there are positive pay-offs for investing in both trial and control plots. However, trial plots have larger NPVs compared to control plots, meaning that there are less additional returns for investing in control plots compared to trial plots. Results also reveal that with 10.5% discount rate, the NPVs are lower than with 8% discount rate, showing that lower discount rates are consistent with higher performance over the long term. This therefore means that at lower discount rate, it is more viable to produce maize using CA than using conventional tillage system. In the case of BRC presented in the study, it was revealed that at both low and high discount rates, the trial plots were more viable than the control plots. Finally, the IRR presented in the study reveal that the trial plots would be able to pay their way much faster than the control plots. Overall, the study found that there are incentives to adoption of CA compared to conventional farming. The message from the different results arising from the use of different discount rates is that farmers should receive assistance at low cost of capital in order for their operations to be viable and this works out well over the long term as shown by the 10-year period projections.
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22

Daniëls, Christiaan Winston. "A Study of the Propagation and Cultivation of Gethyllis multifolia and G. villosa." Thesis, Cape Peninsula University of Technology, 2007. http://hdl.handle.net/20.500.11838/2614.

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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2007.
Gethyllis multifo/ia and Gethyl/is villose (Family: AMARYLLIDACEAE) are indigenous geophytes, growing naturally in the Worcester area, Western Cape. G. muliiiolie falls in the Vulnerable category of the Red Data List of Southern African Plants while G. vil/osa is not threatened at all. Both these species are winter growers and start their growing phase between March and April. These bulbs start their dormant phase between September and October when their leaves start to die down. Flowers of both species are short-lived and borne towards the end of November and early December when no leaves are present. The leaves and berries are simultaneously pushed above ground at the onset of the new growing phase. The fruit of some Gethyl/is species is sweet, juicy, pleasantly aromatic and good to eat and has medicinal properties for the cure of various ailments. The genus is difficult to propagate asexually and very little is known about its propagation and cultivation. The fragrance and medicinal value of the fruit of G. multifolia necessitates future research in the commercial production of this species. A habitat observation study of the two species was conducted to assess the vulnerable status of G. multitolie. Asexual propagation experiments were conducted to find ways of reproducing these two species successfully. A hydro culture study was also conducted to ascertain whether this method of cultivation could be incorporated in the general cultivation of the two species. Finally an in vitro propagation study was conducted to look at faster methods of reproducing these two species. This is of extreme importance in the conservation of the vulnerable G. multitolie. Leaf, root and basal plate cuttings were unsuccessful with no rooting in both species. G. mulfifo/ia bulbs were propagated successfully using twin scaling, bulb cuttings, scooping and scoring propagation techniques with between 80% and 100% rooting success. G. vil/osa was unsuccessful using the above propagation techniques with a 0 - 40% rooting rate. Although Gefhyl/is species in general are sensitive to over-watering, the hydro culture experiment with the sub-irrigation system and leca pellet medium proved to be an effective method of cultivating both species throughout the growing phase. G. mulfifo/ia proved to be unsuccessful during the initial in vitro propagation experiments with no surviving explants during the initiation phase. Results improved with an increased number of trials. It is possible to grow both species by means of in vitro propagation, but more emphasis in future research, should be placed on the multiplication aspect of G. mu/tifo/ia, since not many new buibiets were produced. It was observed through this study that grazing domestic livestock, urban expansion (this includes agricultural extension) and in some cases the lack of interest shown in our indigenous plant species, are some of the main factors influencing the decline in numbers of this species. It is also recommended that more emphasis be placed on the conservation of South Africa's indigenous flora and that the vulnerable status of G. multifolia according to The Red Data List of Southern African Plants, be changed to the "Endangered category" as the factors causing its decline continue to increase.
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23

Mqadi, Lwandle. "Production function analysis of the sensitivity of maize production to climate change in South Africa." Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02132006-083959.

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24

Johnston, Peter. "The uptake and utility of seasonal forecasting products for commercial maize farmers in South Africa." Doctoral thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/4766.

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25

Regier, Gregory. "Impact of genetically modified maize on risk, output, and cost among smallholders in South Africa." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13884.

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Master of Science
Department of Agricultural Economics
Timothy Dalton
Previous research in low-income countries reveals that genetically modified (GM) maize has the potential to increase yield and reduce labor use; however, other issues, especially regarding Roundup Ready (RR) maize, remain mostly unexplored. This research examines the impact of GM maize on yield, cost, and risk among 184 smallholders during the 2009-10 maize production season in two regions in KwaZulu-Natal, South Africa; Hlabisa and Simdlangetsha. Two hybrid maize varieties; Pannar and Carnia, and three GM varieties; Bt, RR, and BR (stacked with Bt and RR) are produced. In both regions, producers of RR and BR maize pay 47% more per kilogram of seed and use 44% less labor per hectare compared to other varieties. Due to low labor costs, net returns from RR and BR varieties are 25% and 40% higher than other varieties in Hlabisa and Simdlangetsha, respectively. Stochastic dominance analysis is used to compare net returns of all five varieties in both regions. RR maize is second-degree stochastic dominant to all other varieties in Simdlangetsha, while no variety is stochastically dominant in Hlabisa. Stochastic efficiency with respect to a function (SERF) analysis indicates that RR maize is the preferred variety for producers over the entire range of risk preferences in both regions. While average maize gross returns are $713 per hectare, risk premiums between $18 and $221 must be paid to RR maize producers, depending on region and farmer risk preference, to persuade them to switch to the second-most preferred variety. Econometric analysis indicates significant yield gains of at least 8% from RR maize, although the yield gain varies greatly when input endogeneity is taken into account. Elasticities of output with respect to labor are 0.41 and 0.82 for RR and non-RR maize respectively, and 0.61 and 0.33 with respect to land. A cost function analysis indicates that RR maize has 19% lower costs per maize plot, which increases to at least a 35% advantage when controlling for selectivity bias. Nonparametric kernel density estimation also reveals consistently lower total and average costs of RR maize at most levels of output, suggesting technological benefits to smallholder farmers from RR maize not available through conventionally-bred hybrids.
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26

Ngqaka, Andiswa Tenjiwe. "The acceptability of selected maize meal types in Mthatha in the Eastern Cape Province in South Africa." Diss., Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-01302009-142136.

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27

Nkohla, Siviwe. "Factors that influence smallholder farmers maize varietal choice :the case of Mhlontlo Local Municipality Eastern Cape." Thesis, University of Fort Hare, 2016. http://hdl.handle.net/10353/3121.

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In South Africa, maize is grown all over the country under various environments including both dry and irrigated agriculture. The majority of maize farmers are smallholders farming on small pieces of land with low input technologies. Additionally, South Africa`s smallholder maize farmers are characterised by low maize productivity, this is despite of the availability of many improved maize varieties on the market. It is clear that professional maize breeders are continuously developing many superior maize varieties with traits more suitable for the commercial farming sector than the smallholder sector. Against this background, this study used a descriptive statistics approach to find out maize varieties and traits preferred by smallholder farmers. The study also evaluated factors that influence smallholder farmers` maize varietal selection choice using descriptive statistics and multinomial regression. The data used for the empirical analysis was obtained from a survey of 200 smallholder farmers in Mhlontlo Local Municipality, in the Eastern Cape Province of South Africa.
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28

Solontsi, Mhlangabezi. "The response of maize to selected ratios of organic fertilizers mixed with inorganic fertilizers in Ndlambe Local Municipality, Eastern Cape, South Africa." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020902.

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The majority of small-scale farmers in the Eastern Cape apply inadequate quantities of manure, inorganic (NPK) fertilizer and Gromor as lone fertilizers or tend to mix manure or Gromor with chemical fertilizers for crops, without any scientific basis (Mkile, 2001). Hence this study – aimed at achieving effective and efficient use of chemical fertilizers, manure and Gromor, either as lone fertilizers or mixed with one another, in maize production – was established. A three-year dry land field experiment, arranged in a RCBD with 3 replicates where cattle manure, chemical fertilizer and Gromor were mixed at different ratios – as treatments FM1 (10 percent fertilizer + 90 percent manure); FM2 (25 percent fertilizer + 75 percent manure); FM3 (50 percent fertilizer + 50 percent manure); MAP (100 percent fertilizer); M (100 percent cattle manure); FG1 (10 percent fertilizer + 90 percent Gromor); FG2 (25 percent fertilizer + 75 percent Gromor); FG3 (50 percent fertilizer + 50 percent Gromor); G (100 percent Gromor) and a control (with nothing applied) – was conducted at the Nolukhanyo agricultural project at Bathurst in the Ndlambe Local Municipality. Maize cultivars PAN 6480 and Sahara were used as test crops. Manure, Gromor and soil were analyzed for their nutrient composition. Data recorded involving number of kernels per cob-1, grain and dry matter (DM) yields for the 2010-11, 2011-12 and 2012-13 seasons, and leaf area index (LAI) – were subjected to Genstat Version 14.1 for statistical analysis. Grain yields of PAN 6480 and Sahara recorded in seasons 2010-11, 2011-12 and 2012-13 were significantly higher (p≤0.05) than those of the controls. In 2012-13, PAN 6480 on treatments FG3 and FG1 produced the highest grain yields (5 327 and 5 107kg ha-1) respectively, while in 2010-11 the highest yield was 3 780kg ha-1. In the 2012-13 season, Sahara on F treatment was the highest with 4 553kg ha-1 whilst there were no significant differences in F and M treatments. Dry matter yields of Sahara were higher than those of PAN 6480 in all seasons. The highest Sahara LAI obtained on FM2 was 5.85 in the 2012-13 season, whereas PAN 6480 had LAI of 4.77 on F treatment, followed by FG3 with 4.72 LAI. PAN 6480 number of leaves for 6 plants in m2 and LAI in week 8 of the 2012-13 season had a positive correlation, r2=0.84. PAN 6480 number of kernels and cob length in the same area correlated quite well (r2 =0.91). Chemical fertilizer corrects the imbalances of nutrients inherent in organic manures and increases both maize grain yields and dry matter yields, and also influences number of leaves and LAI. Treatments FG1, FG3 and FM1 of PAN 6480 resulted in high maize grain yields when planted 13 in late November of the 2012-13 growing season and when water in the soil profile was conserved as a result of good rains received prior to planting. Treatments FG1 (10 percent fertilizer + 90 percent Gromor), FG3 (50 percent fertilizer + 50 percent Gromor) of PAN 6480 produced the highest grain yields (5 107kg ha-1 and 5 327kg ha-1 respectively) in the 2012-13 season, whilst FM1 (10 percent fertilizer + 90 percent manure) gave the highest grain yield (of 4 277kg ha-1) for the same cultivar in the 2010-11 season.
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29

Brooks, Haydn. "The role of field and garden cultivation for food security under a changing climate: the case of Fairbairn and Ntloko villages, Eastern Cape." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/58013.

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The world is becoming more complex due to the increasing occurrence of social-ecological change. This is particularly evident in the developing world, especially on the African continent, where existing vulnerabilities (i.e. endemic poverty, weak governance, overpopulation and HIV/AIDS) are being exacerbated by the impact of climate change. Climate change poses a very real threat to millions of Africans, especially those who rely on the natural world for their livelihoods. The increasing variability of climate and rainfall patterns are said to have dire consequences on agricultural production which is the main livelihood activity of rural dwellers across the continent. The impacts of such change and variability include, changes in the frequency and intensity of droughts, flooding and heavy storms, leading to worsening soil conditions, desertification as well as disease and pest out-breaks which will likely result in reduced crop and livestock yields. A reduction in agricultural production will likely have a negative effect on the food security of millions of people. This study was conducted in the Eastern Cape of South Africa, in two rural villages, Fairbairn and Ntloko located in the former Ciskei homeland, with the purpose of exploring the nexus between climate change, cultivation and food security. This study combined social-ecological thinking with that of political ecology to create a robust lens, in which to analyse the complex interactions between humans and the environment. A mixed methods approach was used to gather the data which consisted of a household survey, using a structured questionnaire as well as semi-structured interviews with various respondents. Quantitative data were analysed using Excel and Statistica 13, whilst coding was used for qualitative data. The main aim of the study was to explore the extent and characteristics of cultivation in the two study sites, the role of household food production in food security as well as the challenges that local cultivator’s face with regards to climate change. In recent decades, there has been a decline in rural agricultural production with many fields that were previously cultivated, lying vacant and unused. However, as this study found, cultivation is still important as over 50% of sampled households cultivated a small area within the homestead. This was mainly done to supplement household food expenditure in order to save cash incomes. The results also found that although participants had perceived negative changes in climate and rainfall (amount, onset, duration), it was not considered the most important challenge for own production. Rather, lack of fencing and capital were seen as major hindrances to efficient own production. Understanding the complexity of own production and food security under a changing climate can help form better and more resilient policies and strategies for rural development, in addition to strengthening future livelihoods of rural people in an ever changing world.
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30

Ndokwana, Ayanda Lawrence. "Techno-economic evaluation of using maize for bioethanol production compared to exporting it from South Africa." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2543.

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Thesis ( MTech (Business Administration))--Cape Peninsula University of Technology, 2016.
Capital investment in bioethanol production requires sound economic feasibility studies. This study investigated the economic feasibility of using maize as a feedstock to produce bioethanol in South Africa. There is a huge opportunity to use dedicated underutilised arable land to grow maize which can be used for both consumption and bioethanol production. The study used 200 000 ton/year of maize that could have been exported to SADC countries to size a plant that produces 80 million litres per year of bioethanol. An advanced bioethanol processing technology that separates the fibre/bran which is burnt in a steam boiler to produce process steam was selected owing to advantages such as low energy consumption and capital expenditure on fermentation and distillation equipment. This study employed a combination of qualitative and quantitative methods to gather data. The findings from a qualitative instrument indicated that a majority of respondents were in favour of the decision of excluding maize made by the South African government. Putting security of food at risk and uncertainty in the profitability of a maize-fed bioethanol plant in the South African context, were two of the primary reasons the respondents opted for an explicit exclusion of maize as a feedstock. Findings from quantitative analysis revealed that the profitability of the bioethanol plant was largely influenced by the prices of feedstock and bioethanol. The 2016 fiscal year indicated the worst case scenario in terms of economic viability of the bioethanol. The astronomically high price of maize due to drought (R5000/ton) rendered the project unprofitable as all of the economic indicators were negative. In the same marketing year, however, the trade balance of maize was positive, indicating a surplus. The study recommended that all of the surplus maize should be exported because it is not economically viable to build a bioethanol plant. The 2011 fiscal year indicated the best case scenario in terms of the economics of the project. This was due to the decrease in price of maize (R1726/ton) and a slight increase in the price of bioethanol. All of the economic indicators were positive, suggesting the benefits of investing in bioethanol production. It was recommended that under normal conditions of maize production in South Africa, a bioethanol plant can be operated simultaneous to maize exportation to other countries without compromising food security, because a maize-fed bioethanol plant uses only a small proportion of maize (14.3%) from the total volume of maize that is exported. Furthermore, it generates more revenue (99.9%) compared to the maize export revenue. It was recommended that sensitivity analysis should be conducted in a holistic manner whereby all variables in the economic model must be adjusted to assess the impact of each on the overall project profitability.
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31

Baloi, Rebecca Tshilambilu. "Technical efficiency in maize production by small-scale farmers in Ga-Mothiba, Limpopo Province, South Africa." Thesis, University of Limpopo, 2011. http://hdl.handle.net/10386/486.

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Thesis (MSc. (Agriculture)) --University of Limpopo, 2011
Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse environments. The study only focuses on the technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. Technical efficiency is the ability of a farmer to obtain output from a given set of physical inputs. Farmers have a tendency of under and/or overutilising the factors of production. The main aim of this study was to analyse the technical efficiency of small-scale maize producers in Ga-Mothiba rural community of Limpopo Province. The objective of the study was to determine the level of technical efficiency of smallscale maize producers and to identify the socio-economic characteristics that influence technical efficiency of small-scale maize producers in Ga-Mothiba. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. Cobb-Douglas production function was used to determine the level of technical efficiency and Logistic regression model was used to analyse the variables that have influence the technical efficiency of maize production. Cobb-Douglas results reveal that small-scale farmers in Ga-Mothiba are experiencing technical inefficiency in maize production due to the decreasing return to scale, which means they are over-utilising factors of production. Logistic regression results indicate that out of 13 variables included in the analysis as socio-economic factors, 10 of them (level of education, income of the household on monthly basis, farmer`s farming experience, farm size, cost of tractor hours, fertiliser application, purchased hybrid maize seeds, membership to farmers` organisation, is maize profitable) were found to be significant and 3 (gender, age and hired labour) are non-significant. However, farm size was found to be the vi most significant variable at 99% level, showing a positive relationship to smallscale maize producer`s technical efficiency. Therefore, it is recommended that government should do the on-farm training since farmers mainly depend on trial and error and farmers` should have access to enough arable land and tractor services. However, farmers need to be trained on matters relating to fertiliser application, on the amount of seeds a farmer should apply per ha, and the importance of using hybrid seed.
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32

Baloyi, Rebecca Tshilambilu. "Technical effeciency in maize production by small-scale farmers in Ga-Mothiba, Limpopo Province, South Africa." Thesis, University of Limpopo (Turfloop Campus), 2011. http://hdl.handle.net/10386/1253.

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Thesis (M.Agric. (Agricultural Economics)) --University of Limpopo, 2011
Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse environments. The study only focuses on the technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. Technical efficiency is the ability of a farmer to obtain output from a given set of physical inputs. Farmers have a tendency of under and/or over- utilising the factors of production. The main aim of this study was to analyse the technical efficiency of small-scale maize producers in Ga-Mothiba rural community of Limpopo Province. The objective of the study was to determine the level of technical efficiency of small- scale maize producers and to identify the socio-economic characteristics that influence technical efficiency of small-scale maize producers in Ga-Mothiba. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. Cobb-Douglas production function was used to determine the level of technical efficiency and Logistic regression model was used to analyse the variables that have influence the technical efficiency of maize production. Cobb-Douglas results reveal that small-scale farmers in Ga-Mothiba are experiencing technical inefficiency in maize production due to the decreasing return to scale, which means they are over-utilising factors of production. Logistic regression results indicate that out of 13 variables included in the analysis as socio-economic factors, 10 of them (level of education, income of the household on monthly basis, farmer`s farming experience, farm size, cost of tractor hours, fertiliser application, purchased hybrid maize seeds, membership to farmers` organisation, is maize profitable) were found to be significant and 3 (gender, age and hired labour) are non-significant. However, farm size was found to be the most significant variable at 99% level, showing a positive relationship to small- scale maize producer`s technical efficiency.Therefore, it is recommended that government should do the on-farm training since farmers mainly depend on trial and error and farmers` should have access to enough arable land and tractor services. However, farmers need to be trained on matters relating to fertiliser application, on the amount of seeds a farmer should apply per ha, and the importance of using hybrid seed.
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33

Baloyi, Rebecca Tshelambilu. "Technical effeciency in maize production by small-scale farmers in Ga-Mothiba, Limpopo Province, South Africa." Thesis, University of Limpopo (Turfloop Campus), 2011. http://hdl.handle.net/10386/882.

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Thesis (M.Sc. Agric.) --University of Limpopo, 2011
Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse environments. The study only focuses on the technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. Technical efficiency is the ability of a farmer to obtain output from a given set of physical inputs. Farmers have a tendency of under and/or over- utilising the factors of production. The main aim of this study was to analyse the technical efficiency of small-scale maize producers in Ga-Mothiba rural community of Limpopo Province. The objective of the study was to determine the level of technical efficiency of small- scale maize producers and to identify the socio-economic characteristics that influence technical efficiency of small-scale maize producers in Ga-Mothiba. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. Cobb-Douglas production function was used to determine the level of technical efficiency and Logistic regression model was used to analyse the variables that have influence the technical efficiency of maize production. Cobb-Douglas results reveal that small-scale farmers in Ga-Mothiba are experiencing technical inefficiency in maize production due to the decreasing return to scale, which means they are over-utilising factors of production. Logistic regression results indicate that out of 13 variables included in the analysis as socio-economic factors, 10 of them (level of education, income of the household on monthly basis, farmer`s farming experience, farm size, cost of tractor hours, fertiliser application, purchased hybrid maize seeds, membership to farmers` organisation, is maize profitable) were found to be significant and 3 (gender, age and hired labour) are non-significant. However, farm size was found to be the most significant variable at 99% level, showing a positive relationship to small- scale maize producer`s technical efficiency. Therefore, it is recommended that government should do the on-farm training since farmers mainly depend on trial and error and farmers` should have access to enough arable land and tractor services. However, farmers need to be trained on matters relating to fertiliser application, on the amount of seeds a farmer should apply per ha, and the importance of using hybrid seed.
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34

Murungu, Farayi Solomon. "Evaluation and management of cover crop species and their effects on weed dynamics, soil fertility and maize (Zea mays L.) productivity under irrigation in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/335.

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The current interest in conservation agriculture (CA) technologies is a result of the need to reduce excessive land degradation in most crop producing areas as well as to enhance sustainable food production. Cover crops that are usually grown under CA to provide soil cover, may offer secondary benefits, depending on the farming system. The concept of growing cover crops is a relatively new phenomenon to smallholder farmers. Production of large biomass yields and weed suppression from cover crops were major challenges affecting success and uptake of CA technologies by smallholder irrigation farmers. Coupled with this, low soil fertility limit maize productivity and reduce water use efficiency on smallholder irrigation schemes in what is largely a water strained agro-ecology in South Africa. While cover cropping can increase maize productivity, benefits of different types of mulch are not well understood, leading to challenges in selecting the most appropriate cover crop species to grow in the Eastern Cape Province (EC) of South Africa (SA) which has a warm temperate climate. With respect to any new technology, smallholder farmers are more interested in the economic benefits. Cover crops have been defined as leguminous or non-leguminous plants used for ground cover in various temporal and special configurations used in crop or animal production systems. The purpose of these cover crops is to improve on or more of the following: soil erosion, availability and cycling of N, P, K, Ca and other nutrients, soil moisture and water infiltration, and weed or pest control (Eilitta et al., 2004).. Improvement of animal or human diet may be additional goals. This definition accommodates diverse systems which may include intercrop and sole-cropping systems. In the Eastern Cape Province of South Africa, a government initiative has promoted the growing of winter cover crops in smallholder irrigation schemes (Allwood, 2006). In other parts of Africa, legume food crops have been simultaneously grown with cereal staples to improve both soil cover and human diet (Eilitta et al., 2004). Winter experiments were undertaken in 2007 and 2008 to evaluate biomass accumulation, C and N uptake, weed suppression and response to fertilization. Winter cover crops planted included; oats (Avena sativa), grazing vetch (Vicia dasycarpa), faba bean (Vicia faba), forage peas (Pisum sativum) and lupin (Lupinus angustifolius). After cover crops were terminated, the effects of residues on weeds, fertility, moisture conservation and maize productivity were undertaken in the 2007/08 and 2008/09 summer seasons. Field studies were also done in the 2007/08 and 2008/09 summer seasons to investigate effects of strip intercropping patterns (3:2; 4:2; and 6:2 patterns) of maize (cv. PAN 6479) with mucuna (Mucuna pruriens) or sunnhemp (Crotalaria juncea) on maize productivity and summer cover crop biomass production. In a separate experiment effects of relay intercropping sunnhemp, mucuna and sorghum (Sorghum bicolor) on biomass accumulation and maize productivity were investigated. Decomposition, N and P release from both winter cover crops and summer cover crops were also assessed in laboratory incubation experiments. Oats, grazing vetch and forage peas cover crops produced mean dry mass of 13873 kg/ha, 8945.5 kg/ha and 11073 kg/ha, respectively, while lupin had the lowest dry mass of 1226 kg/ha over the two seasons. Oats responded to fertilization while, there was little or no response from the other winter cover crops. Oats and grazing vetch also reduced weed density by 90 % and 80 % respectively while lupin only reduced weed density by 23 % in relation to the control plots. Nitrogen uptake was 254 kg N/ha for oats while it was 346 kg N /ha for grazing vetch. In the subsequent summer season, grazing vetch and forage pea residues significantly (P < 0.01) improved soil inorganic N. Oat and grazing vetch residues significantly (P < 0.05) reduced weed dry masss and weed species diversity compared to plots with lupin residues and the control. Lack of maize fertilization tended to reduce maize yields but not for maize grown on grazing vetch residues. From an economic perspective, grazing vetch resulted in the highest returns. Decomposition of winter cover crops was much faster for grazing vetch followed by forage peas and lastly oats. Oats had 40 % ash free dry mass remaining after 124 days while grazing vetch and forage peas had 7 % and 16 % respectively. Maximum net mineralized N and P were greater for grazing vetch (84.8 mg N/kg; 3.6 mg P/kg) compared to forage peas (66.3 mg N/kg; 2.7 mg P/ha) and oats (13.7 mg N/kg; 2.8 mg P/kg). In the strip intercropping trials, sunnhemp achieved the highest biomass yield of 4576 kg/ha in the 3:2 pattern while mucuna achieved 1897 kg/ha for the same strip pattern. The 3:2 strip intercropping pattern slightly depressed yields, however, yield reduction was more pronounced in the first season where water stress was experienced. Growing maize on previous cover crop strips failed to increase maize productivity probably due to weed growth during the fallow reducing mineral N in these strips. Decomposition was faster in sunnhemp leaves and mucuna compared to sunnhemp stems. Sunnhemp stems had about 65 % of ash free dry mass remaining after the end of the experiment at 132 days while just over 10 % of mucuna and sunnhemp leaves still remained. Mucuna mineralized 60 mg N/kg and 3.2 mg P/kg and sunnhemp mineralized 45 mg N/kg and 3.5 mg P/kg. Relay intercropping did not significantly (P > 0.05) affect maize biomass and grain yield. Sorghum experienced the largest drop in biomass when relay-intercropped with maize. Mucuna resulted in the highest N uptake (271 kg N/ha) in sole cropping while sorghum had the lowest (88 kg N/ha). Grazing vetch results in high biomass yields with minimal fertilizer application in a warm-temperate climate. Grazing vetch mulch is also the most cost effective mulch for better early weed control, improving soil mineral N status, water conservation and ultimately enhanced maize productivity in smallholder irrigation maize-based systems. The 3:2 pattern maximizes summer cover crop biomass yields compared to the 6:2 and 4:2 patterns. However, the 3:2 pattern may slightly depress yields in a water stressed environment. Relay intercropping mucuna, sunnhemp and sorghum into a maize crop at 42 days after maize sowing has no effect on maize productivity while cover crop biomass yields are low. Having a long winter fallow period after maize harvesting, a common practice in the study area, reduces the positive impact of legume cover crops on soil mineral N. Results suggest that winter cover crops may result in weed control, soil fertility and maize yield improvement benefits while a long fallow period may cancel-out these benefits for summer cover crops. Grazing vetch is a cost effective cover crop that produces high maize yields with minimal fertilizer input. Maize growing on oat mulch requires more fertilizer application than crops growing on grazing vetch mulch. Conservation agriculture systems in which summer cover crops are grown alongside the maize crop with a long winter fallow period do not produce the intended CA benefits.
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35

Swart, Jacobus Johannes. "The impact of the logistical process on food safety and quality for maize export in South Africa." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/1235.

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To be submitted in fulfilment of the requirements for the degree MASTER OF TECHNOLOGIAE: In Quality In the Faculty of Engineering AT THE CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012
Over the last decades, due to the lack of safety concern and inadequate quality management in logistical process, it caused unsafe and poor quality of maize products. Thus, this study looks into the key factors that affect maize exports from South Africa in order to improve the logistical processes and reduce the risks involved in the process. The main risks associated with poor traceability and logistical chain management of maize export, as well as issues pertaining to non-conformance to the different food safety standards were explored. Data were collected a group of food business operators (FBO) (n1=127) and food business inspectors (n2=20) through a number of interviews and a self-administered questionnaire. Data were then analysed by using the SPSS-V19 programme to generate descriptive statistical results to determine the specific needs and gaps within the current system as well as providing recommendations on the specific food safety changes pertaining to the maize export industry. The results showed that there is a lack of understanding among role-players regarding FBO legislation. In the comparison of many large companies, there is only a few small role-players adhere to the legislation pertaining to food safety and traceability. This has impacted on the quality of maize products negatively. This strongly suggested that all role-players that handle maize for export must be registered for FBO codes with Department of Agriculture, Forestry and Fisheries. The study also recommended that the Perishable Products Export Control Board (PPECB) should inspect and confirm the legitimacy of the FBO codes that appears on the maize export documentation. Keywords: Quality, food safety, food business operator, maize export, logistical processes, and traceability.
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36

Ramoroka, Mokgadi Mizen. "Grain yield, gravimetric moisture content, dry matter accumulation and chlorophyll production in maize-legume intercrop under minimum and conventional tillage systems." Thesis, University of Limpopo (Turfloop Campus), 2008. http://hdl.handle.net/10386/639.

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Thesis (M.Sc. (Agriculture)) --University of Limpopo, 2008
Maize is a dominant crop in smallholder farming systems in the Limpopo province of South Africa, generally cultivated as intercrop with grain legumes. The major constraint in this cropping system is inadequate soil moisture during the growing season, which also limits nutrient availability to the component crops. The minimum tillage system has been reported to improve soil moisture availability on farmers’ fields but this has not yet been verified in an intercropping system in the province. The objective of this study was to quantify grain yield and chlorophyll production of intercropped maize, and to assess seasonal moisture availability under minimum tillage (MT) and conventional tillage (CT) systems. Dryland field experiments were conducted at two locations in the province namely, farmer’s field at Dalmada in 2002/2003 and 2003/2004 growing seasons and at the University of Limpopo Experimental farm at Syferkuil during the 2003/2004. The experimental design was a randomized complete block in split plot arrangement at all locations and seasons. Tillage systems consisting of conventional tillage and minimum tillage were the main plot treatments, whereas five different cropping systems namely, sole maize, and maize intercrop with cowpea (variety, Bechuana White), cowpea (variety, Agripers), Lablab bean (variety, Rongai) and Velvet bean were assigned as sub-plot treatments. Maize grain yield in 2002/2003 at Dalmada was significantly lower (357 kg/ha) under CT relative to 755kg/ha under MT. In 2003/2004 at Dalmada, grain yields under the two systems were similar, where as at Syferkuil, 15% higher grain yield results was obtained under MT. Minimum tillage systems resulted in higher number of maize cobs per plant at Dalmada in both growing seasons and weight per cob was higher under MT at both locations and seasons. At Dalmada, significantly higher soil moisture was recorded under the MT relative to the CT depending on depth and sampling dates. Chlorophyll content of the youngest fully expanded leaves of maize was generally higher under MT than CT, but this was observed only at the later stages of plant growth. The results also showed that the rate of senescence (reduced chlorophyll content in older leaves) was higher in maize plants grown under CT relative to those under MT. The minimum tillage system has shown the potential of being a superior system for dryland maize production, but further research involving additional locations is required to ascertain this fact.
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37

Musunda, Bothwell Zvidzai. "Evaluation of cover crop species for biomass production, weed suppression and maize yields under irrigation in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/347.

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Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.
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38

Miller, David. "Outdoor cultivation of Gracilaria in pond and raceway systems at Jacobsbaai Sea Products (Pty) Ltd., South Africa." Thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/26643.

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39

Louw, Melissa. "The social practices of cultivation and gathering of medicinal plants in Ebenhaezer, Matzikama, Western Cape, South Africa." Thesis, University of the Western Cape, 2016. http://hdl.handle.net/11394/5533.

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Magister Artium - MA
This study aims to investigate the extent to which the increasing demand for medicinal plant and the resulting pressure on local cultivators to meet the demand impact upon cultivation and gathering practices of such plants. The specific focus is on the social practices of cultivation and gathering of medicinal plants in Ebenhaezer, a small-scale peri-urban town in Matzikama in the Western Cape Province in South Africa. This study will utilize survey and in-depth interviews techniques complemented with a focus group discussion on observed cultivation and gathering practices.
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Nxumalo, Bongiwe Goodness. "The analysis of the economic impact of climate change on maize production under different farming systems: the case of smallholder Farmers in Jozini Municipality, KwaZulu Natal Province, South Africa." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1021277.

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Maize is the most grown crop by the farmers in Jozini. Therefore, the main objective of the study was to assess the economic impact of climate change on maize production under different farming systems in Jozini Municipality in KwaZulu Natal (KZN). The study was looking at the smallholder farmers producing maize under dryland and irrigation system. A total of 100 farmers were selected for the study (40 from dry-land and 60 from irrigating farmers). Cluster and random sampling procedures were used to select the sample. Questionnaires were used for the collection of primary data, from the respondents (maize farmers). Data was analysed using descriptive statistics (frequency, percentages), gross margin, regression analysis and the Ricardian model. Data for computing gross margins and net revenue was taken from the on-farm trials. Gross margin was used on regression analysis and the net revenue was used on the Ricardian modelThe results of the regression analysis indicated that land size, farmer’s experience to farming, level of education, use of fertiliser, use of irrigation and the yield obtained were significant and have a positive relationship with farmers gross margin. The results of the Ricardian model indicated that climate change affects both farming systems, but farmers that are producing under dryland are the most affected farmers because they rely more on climate variables especially rainfall for their production. So a change in climate variables affects maize farmers’ productivity and thus affecting farmers’ gross margin and net revenue. The study recommends that the farmers must use irrigation in order to support maize production even in the absence of rainfall. Farmers must also adapt to the short growing season so that they will be able to produce even in the presence of climate change.
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Ganyani, Lloyd Munashe. "Evaluating summer cover crop species and management strategies for rainfed maize based cropping systems in the central region of the Eastern Cape Province of South Africa." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/373.

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The overall objective of the whole study was to assess whether conservation agriculture (CA) systems can work in the Eastern Cape Province (EC). The CA systems were engaged through cover cropping to address land degradation problems by emphasizing high biomass production in order to realize short term benefits such as moisture conservation, weed suppression and soil fertility benefits under rainfed conditions in the central region of the Eastern Cape province. Since rainfall is the most limiting factor to crop production in the EC, a within season rainfall distribution analysis was conducted to expose the quality of the season (onset, end and duration) and hence the feasibility of CA systems to guide agronomic decisions by farmers in EC. To assess season parameters, thirty four years of daily rainfall was collected from the University of Fort Hare Research station and used to conduct the rainy pentad (5 day rainfall totals) analysis and the daily rainfall analysis using INSTAT software programme. Based on the pentad analysis, results showed that Alice does not have a rainy season in 1 out of 2 years (50% probability) but has one in 1 out of 4 years (25% probability level). This criterion proved to be harsher and conservative when compared to the daily rainfall approach which is more precise in measuring trends on season parameters. The daily rainfall analysis indicated a 65% feasibility for the dry land cropping systems in the EC. The pentad analysis however was effective in illustrating seasonality and it showed that the wet season begins on the 1st of November, ending on the 22nd of March lasting for 140 days. Though the season duration appeared too long, the existence of dry spells during critical growth stages adversely affects the quality of the season. The daily rainfall analysis also managed to derive a signal which can guide planting decisions. For planting to be successful, this analysis determined that 20 mm of rain should be received in two consecutive days after the 1st of November. A screening trial for cover crop biomass production and weed suppression was conducted on-station Fort Hare Research Farm (32°46' S and 26° 50' E), and Msobombvu village (MSBV) (32°44' S, and 26° 55' E) over two seasons (2007/08 and 2008/09). Six summer cover crops i.e. cowpea (Vigna unguiculata), dolichos lablab (Dolichos argenteus), sunnhemp (Crotalaria juncea), buckwheat (Fagopyrum sagittatum), forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were evaluated for biomass yield, and weed suppression. Decomposition rates, moisture conservation and residual effects of these cover crops on the succeeding main crop were also evaluated under dryland conditions. The screening trial was laid in randomized complete block design replicated three times. Forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were identified as high biomass producers and their dry matter yields ranged from 8 -12 t ha-1. These cover crops can be useful in generating high biomass in rainfed cropping systems in the EC. Other cover crops produced 3 - 4 t ha-1 of biomass which fell short of the 6 t ha-1 expected benchmark. However, these biomass yields were important in weed management since all cover crop species showed a similar degree of weed suppression which surpassed the weed fallow treatment. As dead mulches, the cover crops failed to show residual moisture conservation and weed control benefits for the succeeding maize crop mainly because of poor residue persistence, and low harvestable fallow rainfall. Buckwheat (Fagopyrum esculentum), was selected for further investigations in a follow up trial on station in 2008/09 season because of its weed smothering qualities, suitability to short cycle rotations, and possible allelopathic properties. The trial aimed at finding weed and cost effective management options of buckwheat that are none detrimental to the succeeding maize crop. Results showed that cropping systems where buckwheat is followed by a main crop may not work as they are unprofitable with respect to R100 rand invested. Though perceived to have allelopathic properties, buckwheat failed to demonstrate the possibilities of allelopathic action against weeds. Intercropping trial was conducted on-station in 2007/8-2008/09 seasons to try and find better ways of fitting legume cover crops into maize based cropping systems without compromising production of staple cereals on limited landholdings. The trials evaluated three factors in factorial combination, cover crop planting date, intercropping strategy, and cover crop species. The trial was laid as 2 x 2 x 3 factorial arranged in a split-split plot design. The main plot factor was cover crop planting date, cover crops simultaneously planted with maize and cover crop planted two weeks after planting maize (DKC 61-25). The sub-plot factor was intercropping strategy, strip intercropping and betweenrow intercropping. The sub-sub-plot factor was cover crop species, Dolichos lablab (Dolichos argenteus (Highworth), and Cowpea Vigna ungiculata (Agrinawa) plus control plots of sole maize. Results showed that same time planting of leguminous cover crops with maize using the in-between row intercropping patterns can derive appreciable system biomass (maize/cover crop) yields, utilize land efficiently whilst getting favourable maize grain yield. Based on the rainfall analysis, results showed that the probability of success when relay seeding cover crops after two weeks into standing maize is low (15% chances of success). This suggests that relay intercropping strategies would not work due to the unavailability of a good quality season.
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42

Avuletey, Richard. "Analysis of technical efficiency of small-scale maize producers: a case study in Tsolo magisterial district in O.R Tambo district in the Eastern Cape of South Africa." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1016191.

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Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse conditions and in diverse environments. The study only focuses on technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. In such a setting, increased output will depend more on efficiency improvements and assessing the scope for such efficiency improvements within the system is a crucial need. The objective of the study was to determine the level of technical efficiency and to identify the socio-economic and institutional characteristics as well as the entrepreneurial spirit that influence the technical efficiency of small-scale maize producers in the Tsolo magisterial district. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. The stochastic frontier model was used to determine the level of technical efficiency. The Multivariate OLS was used to analyze the socio-economic factors and institutional characteristics that have influenced the technical efficiency of maize production. A similar linear regression model was used to estimate the influence of positive psychological capital and entrepreneurial spirit on the technical efficiency of maize production. The stochastic results revealed that small-scale farmers in Tsolo are technically efficient at 98 percent in maize production and experience increasing return to scale (1.37), which means that increase in the use of inputs, will as well increase their productivity and efficiency. The inefficiency model results indicated that age, years in farming, household size and extension contact significant and 3 variables, namely, as years in farming, extension contact and farm size are significant in the OLS model. Lastly the results of the linear regression indicated that, out of the 4 variables estimated in the entrepreneurial spirit, self-efficacy and resilience were significant with respect to its responsiveness to total maize output.
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Mahlase, Mankurwana H. "Exploring the uptake of genetically modified white maize by smallholder farmers: the case of Hlabisa, South Africa." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/24452.

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The use of genetically modified (GM) crops to resolve food security and poverty issues has been met with controversy and scepticism. The rationale for this research was to highlight the nuanced reasons as to why smallholder farmers are motivated to use agricultural biotechnology. The aim of this study was to explore the uptake of GM maize by South African smallholder farmers in order to contribute towards understanding the implications of agricultural biotechnology in smallholder agriculture. Using the case studies of Hlabisa in KwaZulu-Natal, the objectives were; (i) to investigate the perceived benefits and problems associated with the uptake of GM maize. (ii) to identify which institutional, political, social, and environmental factors influence the choices and decisions made by smallholder farmers to grow GM maize and (iii) to assess how GM maize has affected the well-being of farmers, including social cohesion in the farming communities. The reason Hlabisa was selected for the case study is that it represents one of the few areas in South Africa where GM crops (white GM maize in particular) has been cultivated on a long term basis by smallholder farmers. The necessary information was obtained through the means of a survey in which a number of farmers in the Hlabisa area participated in this regard the participants were; 40 farmers who used white GM maize that possessed the herbicide tolerant and insect resistant traits; seven farmers who used white insect resistant maize and 11 non-GM maize farmers. In addition, five key informant interviews and three focus group discussions were used to collect data. The history of agriculture in the area reveals that modern maize varieties were introduced when agricultural extension officers started operating in the area, beginning with maize seed hybrids in the 1970s. Maize hybrids were framed as better varieties compared to traditional maize in terms of performance. Later, in the 2000s, the seed company Monsanto, and the local department of agriculture introduced various GM maize varieties through farmers' days. This marked the addition of another institution providing so-called expert knowledge about maize farming in Hlabisa. It was argued that relationships between the local department of agriculture, farmers' associations and seed companies were instrumental in encouraging the uptake of GM maize seeds. It is also posited that the GM maize farmers in this study received pseudo-extension and advisory services. These had the agenda of promoting GM maize varieties over traditional varieties, relaying inappropriate agricultural knowledge in the process. There was also a lack of transparency in communicating the potential health and environmental risks associated with GM maize farming. Farmers were unaware that they were legally not allowed to save and exchange the patented GM maize seeds and had to plant refugia to prevent insect resistance. The uptake of GM maize has not significantly affected the seed saving and exchange practices of farmers. Fifty-two percent (24) of the 47 respondents no longer exchanged or saved any of their maize seeds in the study. A chi-squared test for independence indicated that the GM maize farmers were less likely to save and exchange seeds. The non-GM maize farmers were deterred from planting GM crops by the expensive input costs. The issue of affordability of the GM technology also extended to GM farmers, most of whom used social grants to purchase their GM maize seeds. Forty-nine percent of these farmers were in debt due to their uptake of the GM maize. Despite this debt, 74% of respondents claimed that they had perceived an improvement in their quality of life after using white GM maize, as they harvested enough maize to last them to the next planting season and were able to sell surplus maize. However, they only made marginal profits to cover household expenses. There are several conclusions that can be drawn from this study. First, there is a noticeable shift from farmers relying on their own knowledge and experience to using that of seed companies and agricultural extension officers. Second, Seed companies are beginning to fill the gaps left by public extension and advisory institutions and farmers are vulnerable to making uninformed decisions as they are not given relevant information. It is recommended that farmers are given agency through the provision of transparent information. This should be the responsibility of the government and not seed companies with vested interests. The government should try to move away from the idea that farmers need to scale up production through using modern varieties. A better approach would be the strengthening of appropriate support and extension services for South African smallholder farmers who use various maize systems. Lastly there is a need to raise awareness about the social, economic and environmental implications to farmers who elect to use GM seeds.
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44

Funke, Thomas Bernhard. "From farm to retail : costs and margins of selected food industries in South Africa." Diss., University of Pretoria, 2006. http://hdl.handle.net/2263/27973.

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This dissertation highlights the need for a formal methodology to be developed in order to unpack complicated supply chains and to publish information that explains how the farm value or farm to retail price spread of certain products can be calculated and how these results are to be analysed. It is for this reason that the study reviews and applies the methodology used for the calculation of price spreads and farm values. It applies the methodology to five food supply chains of maize, fresh milk, beef, poultry and sugar. The analysis of farm values and spread has already been developed in an international context but it has not of yet been applied in the South African context. It is therefore the aim of this dissertation to illustrate how this methodology can be applied here and how this can be done on a continuous basis. The main objectives of the study are:
  • To review and apply the methodology used for the calculation of price spreads and farm value, as well as to analyse trends of five agricultural commodities in the food sector.
  • To understand not so much on what is behind the previous rise in food prices, but rather on why; when the farm or producer prices fall, do retail prices on certain goods not fall by the same margin? The question that needs to be asked is who or what is responsible for this? A detailed analysis of the supply chain of various products could prove invaluable in the process of understanding price movements.
  • To investigate the degree of transparency of information in the South African food sector is investigated by looking at the market share that the various supermarket chains hold. Since competition and concentration of role players within this sector of the economy plays such a vital role in the determination of the market’s fairness, it is important that the size and the percentage of market share that the retailers hold in the market is researched and understood. A special section focuses on the market share that some retailers hold as a percentage share of the entire supermarket retail sector.
  • To discuss the estimation of the specific cost incurred, at various levels,within the maize-to-maize meal and beef-to-beef products supply chains, in detail. This involves designing a framework for the continuous analysis of food prices and costs contained within these two supply chains and understanding the costs incurred by the different role players.
In applying the methodology to estimate farm value and farm to retail price spread it is determined some of the commodities such as beef, milk and sugar experienced a slight widening of the farm to retail price spread, while the opposite occurred with the price spread of maize meal and broiler meat. A widening farm to retail price spread shows that farmers’ share in terms of the retail price is declining and as a result their share of the final product has become less. Farmers in the beef, milk and sugar sectors experienced this while maize and chicken farmers experienced the opposite, in other words a narrowing spread and as a result they are earning more of the final product. In applying the various econometric tests in order to test for asymmetric price behaviour in the various supply chains it was found that in four of the five supply chains the transmission of increases in producer prices where not smoothly and timely transmitted to the retail price. The models that fared worst in the analyses were those of the sugar, beef, fresh milk and a part of the maize supply chain. The inabilities of the models to show any form of significance, even when tested economic theory is applied indicate that something is amiss within the supply chains. Asymmetric price transmissions, a lack of accurate data or unjust market behaviour by role players within the supply are some of the factors that could be responsible for this. The analysis in chapter 5 is based on these findings. A proposed framework for an in depth analysis of such a supply chain is documented there. The detailed analysis of costs and margins in the maize to maize meal and beef supply chains, have shown that there are many stages along the supply chain, where various costs and profits can have severe influences. In chapter 5 a detailed analysis has been done on this with the objective of developing a framework that can be applied to an industry. This chapter lends specific detail as to where the influences of such costs can be the greatest. The results point out that, of the five supply chains, only two of them, namely chicken and maize (from farm gate to miller), adhered to some form of economic theory, whereas the other three either suffered from insignificant/unrepresentative data or actual price transmission asymmetry. On the basis of this, the supply chains of both super maize meal and the five selected beef cuts were unpacked with the profit margin and the role player’s cost of formation at the different levels within the value chains. A conclusion can be made that parts of the maize supply chain (milldoor to retailer), the beef supply chain, the sugar supply chain and the dairy supply chain all suffer from asymmetric price transmissions or alternatively, a data discrepancy. This conclusion is drawn from the fact that the Error Correction Models ECMs for these specific industries failed most of the diagnostic tests and contained some insignificant variables. The diagnostic tests did not only test for misspecification but included a standard procedure, using the Jarque Bera test for normality, the ARCH LM test for heteroscedasticity, the White test for heteroscedasticity as well as the Breusch Godfrey test for serial correlation. The fact that the ECMs of these supply chains had these problems does give rise to a concern as to the transmission of prices within some of the supply chains within the South African food industry. The applied methodology used in unpacking of the supply chains, was applied with the aim of developing a framework that can be adapted and used for similar analyses in future. The aim of this methodology was solely on developing and applying a methodology to two of the five supply chains, partly based on the results in chapter 4 but also on the importance of the commodities in the South African food industry, and to illustrate, by using real data, how this framework can benefit future research.
Dissertation (MCom(Agric Economics))--University of Pretoria, 2006.
Agricultural Economics, Extension and Rural Development
unrestricted
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45

Gericke, Maria Catharina. "Aspects of amphibian chytrid infections in South Africa / M.C. Gericke." Thesis, North-West University, 2008. http://hdl.handle.net/10394/3713.

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The waterborne pathogen Batrachochytrium dendrobatidis (Bd), amphibian chytrid, is implicated as being the causative agent for global amphibian declines. The fungus attacks the keratinized skin of adult and postmetamorphic animals and the keratinized mouthparts of tadpoles. Postmetamorphic animals seem to be more susceptible to Bd than tadpoles and adult frogs. Hypotheses exist that the origin of the fungus is in Africa. During the study different aspects of Bd infections in South African frogs were examined including the distribution of Bd, cultivation of Bd, preservation of cultures, the morphology of Bd as an infection as well as in culture and finally differences in host defense. Positive and negative localities for Bd were identified through surveys conducted in South Africa. These data will be contributed to the Bd Mapping Project and the African Bd Database in order to determine whether chytrid has any environmental preferences. Cultures obtained from the positive localities were maintained and cryopreserved for use in numerous experiments. In a future study, DNA extractions from the cultures will be analyzed using multilocus sequence typing in order to determine the sequence type of South African strains in comparison with global strains. This will provide important epidemiological information concerning the origin and control of Bd. The morphology of Bd was also examined using scanning electron microscopy and laser scanning confocal microscopy. Damage due to Bd infections was more severe on the larval mouthparts of Amietia vertebralis than that of Hadromophryne natalensis. The adverse effect of Bd is therefore not limited to postmetamorphic animals. Confocal microscopy uses fluorescent stains and lasers to examine specific structures within organisms. An especially effective stain used during confocal microscopy on Bd is Calcofluor White M2R. Due to its specificity this stain can be used as an effective screening tool for Bd in tissue. The role of antimicrobial skin peptides as a defense against Bd was also examined. A. vertebralis experiences die-offs due to chytrid, while H. natalensis does not experience the same effect in the presence of Bd. H. natalensis possess more antimicrobial skin peptides against Bd with a higher effectiveness than peptides extracted from A. vertebralis. This may explain the observed susceptibility of A. vertebralis to Bd. The relevance of this study is in order to identify areas in South Africa in which the probability of finding Bd is high. This will help in the surveillance of Bd and in the identification of susceptible species to be monitored and protected against the fungus. The effect of Bd on frog species can also be determined by means of exposure experiment using cultures isolated during this study. Through the identification of peptides effective against Bd, predictions can be made with regard to the susceptibility of different frogs to Bd, improving our ability to protect the amphibian biodiversity in South Africa. With the use of confocal microscopy in the examination of Bd, we became the first group to use the method. By the identification of a stain with a high potential as a screening tool, we also contributed to the more efficient identification of Bd in tissue. Keywords: Batrachochytrium dendrobatidis, Bd, amphibian chytrid, distribution, cultivation, antimicrobial skin peptides, laser scanning confocal microscopy, Amietia vertebralis, Hadromophryne natalensis, South Africa
Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2009.
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Spriggs, Amy Clare. "Symbiotic N² fixation in cyclopia vent. spp. (honeybush) : towards sustainable cultivation in the Western Cape of South Africa." Doctoral thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/6215.

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Includes bibliographical references.
An indigenous cash crop, called honeybush (Cyclopia spp., Fabaceae), has recently gained popularity in the Western Cape of South Africa and its potential for cultivation is being investigated. The crop is an N²-fixing legume and its yields would therefore be improved by enhancing its N²-fixing capacity. This would allow increased tea yields without the need for chemical fertilizers, promoting the crop's status as an organically farmed health product, limiting the environmental degradation associated with N fertilizer use and benefiting small-scale farmers in the region who cannot afford chemical fertilizers.
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47

Da, Serra Maria Fatima. "Fungal and substrate-associated factors affecting lignocellulolytic mushroom cultivation on wood sources available in South African [i.e. Africa]." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1004080.

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Vast- quantities of lignocellulosic materials, representing potential substrates for the cultivation of speciality mushrooms, are produced annually in South Africa. A number of these materials are derived as waste products of the timber and agricultural industries, e.g. Maranti (Shorea spp.) and Port Jackson Willow (Acacia longifolia) respectively. The screening of various wood-degrading fungi, which are cultivated worldwide for their production of speciality mushrooms, indicated that under the environmental conditions considered, certain species were adapted to cultivation on these lignocellulosic wastes (Pleurotus species) whereas others were not (Lentinus edodes and Flammulina velutipes). Furthermore, intra- and interspecies specific differences in the growth and production potential of the various lignocellulolytic fungi investigated on synthetic and natural medium were discovered. Biochemical and genetical investigations of these strains indicated differences between and within species which were often significant. Species varied qualitatively and quantitatively in the lignocellulolytic enzymes produced, which was loosely correlated with productivity on the different media investigated. Genetical studies, using RAPD fingerprinting, indicated that the Pleurotus genus is highly variable which supports the observed differences in growth, yield and enzymatic activity between different strains and species.
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48

Neno, Thembisile Wiseman. "Attitudes of rural men towards the advancement of rural women : a study of Thandanani and Umngazi maize producing projects." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/2905.

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Thesis (MPhil (Sociology and Social Anthropology))--University of Stellenbosch, 2007.
The South African woman, due to political and social change, has a totally new role to play in the workplace. The study focused on attitudes by men towards black rural women who are participating in the upper echelons of rural economic development and have to display their full potential in positions previously and traditionally reserved for rural men. The research was conducted in the Port St John’s irrigation maize producing projects of Thandanani and Umngazi. The study develops and investigates the hypothesis that rural men have negative attitudes to the advancement of rural women. The researcher uses the theory of social closure, that originated from Max Weber, within which rural women’s upward mobility and resistance of men thereto can be placed. Social closure refers to the phenomenon that a hierarchical or stratified social system tends to develop in which an elite group seeks to maximize rewards by restricting access to resources to a limited circle of the eligible. In this a top-down process of exclusion and the limitation of opportunities, originating from rural men, is assumed. In contrast, rural women may attempt to gain access to opportunities enjoyed by rural men through a process of usurpation. In order to investigate these possibilities a social attitude survey was conducted among 45 male members of the Thandanani and Umngazi maize producing projects. Questionnaires in Xhosa language and based on summated rating scales were used. The rural men’s attitudes towards women were found to be differentiated. On the one hand, positive attitudes were found that support the advancement of women, accept equal opportunities and their creativity and helpfulness. On the other hand, sexist attitudes were observed that perceive women to be less capable and inherently inferior to men. Men, as the resourceful in-group, believe and think themselves as superior to women as the inferior out-group who as a result occupies lower positions of wealth and power. Men perpetuate their advantageous position and pass it to their offspring. These findings are borne out by literature where it is stated that men undermine cooperation between men and women in decision-making (Colclough 1999), regard women as minors (Cross et al 1988; Lessing 1994), and do not see them as relevant and worthy (Epstein 1970). Men are seen to have a desire to protect their advantage and create rules of distribution of resources to their own favour (Nel 2003). Development projects towards the advancement of women, who are believed to be inferior and incapable, are therefore deemed to fail. It is recommended that all agencies should adopt and implement equal opportunity programmes, feminists need to explore possibilities and give attention to how and in what areas men can be approached to enlist support in the struggle for women’s opportunities and rights; and cooperatives be established to break gender stereotypes through training and removal of boundaries that created occupational segregation between the genders.
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49

Rudolph, Nicole. "Efficacy of selected rhizobacterial isolates for biocontrol of Rhizoctonia solani and growth promotion of maize in South Africa." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/79181.

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Abstract:
Plant growth promoting rhizobacteria (PGPR) are bacteria that colonize the volume of soil surrounding plant roots (known as the rhizosphere) which, when in association with a suitable host plant, promote plant growth. The growing demand for sustainable crop production strategies has placed increasing emphasis on PGPR and their potential use in agriculture. The current study therefore focused on the beneficial effects of PGPR isolates (selected from the PGPR culture collection at the University of Pretoria) on maize (Zea mays L.) and the ability of these isolates to control Rhizoctonia solani Kühn. The seed quality and vigour of two maize cultivars (PAN 6236B and PAN 6Q-308B) was determined using the standard germination, moisture and various vigour tests. PAN 6Q-308B was found to have lower vigour and was selected for use in the remainder of the tests performed in the study. In a modified seed germination bioassay the percentage germination, seedling mass, shoot and root length of PAN 6Q-308B was increased by selected PGPR isolates. The vigour index (VI) of PAN 6Q-308B was also increased by five isolates (S6, S7, T19, T29 and A32) which were then selected for evaluation in the greenhouse. In the greenhouse pot trial isolates T19, S7 and T29 gave the most promising results in terms of increasing the dry mass of maize seedlings. These isolates were evaluated in a formulation efficacy trial where they were applied individually and in combination as a soil drench, seed treatment and liquid suspension or powder formulation applied to a pelletised compost carrier. The four most effective treatments at increasing the dry root mass of maize included a soil drench application of either isolate T29 or T19, a soil drench application of the consortium of isolates T19, T29 and S7, and a powder formulation of isolate T29 applied onto the compost pellet carrier. Isolates A08, A07 and T19 were the most effective at reducing the disease symptoms of R. solani Kühn and increasing dry root matter above that of the R. solani inoculated control in a seedling tray trial. Pot trials were conducted to assess the efficacy of isolates A08, A07 and T19 for control of R. solani, when applied as a seed treatment or soil drench. All three isolates failed to control the pathogen when applied as a seed treatment but a soil drench of isolate T19 was found to be very effective. A six month shelf-life study was conducted to determine the survival of the PGPR isolates T19, S7 and T29 applied to a novel carrier comprising pelletised composted chicken manure. The isolates were individually applied to the pellets in a liquid or powder form. The latter was found to be the most suitable for supporting the survival of the PGPR isolates up to six months at 25˚C. The study revealed that the viability of the isolates decreased more rapidly at a temperature of 35˚C as opposed to 25˚C, and that the cell numbers of isolate T19 remained the most stable throughout the six months incubation period in comparison with the other isolates.
Dissertation (MSc)--University of Pretoria, 2014.
Microbilogy and Plant pathology
MSc
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50

Njaimwe, Arnold Ngare. "Tillage and crop rotation impacts on soil, quality parameters and maize yield in Zanyokwe Irrigation Scheme, South Africa." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/460.

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Abstract:
Intensive tillage and monoculture cropping practices reduce soil C accumulation hence increasing soil vulnerability to chemical, physical and biological degradation. This study focussed on enhancing biomass production of wheat and oat winter cover crops as a means of increasing C sequestration in the low organic C soils of the central part of Eastern Cape Province. The specific objectives were (i) to evaluate the short-term effects of no till and cereal-fallow based crop rotations on; soil organic matter related parameters, pH and electrical conductivity, (ii) soil bulk density, water retention and aggregate stability, (iii) soil microbial biomass C and N, mineralizable N, soil respiration, and dehydrogenase enzyme activity, (iv) grain yield, soil nutrient concentration (N, P and K) and their uptake by maize, and (v) to identify soil parameters with high sensitivity to tillage under maize-fallow-maize, maize-wheat-maize and maize-oat-maize rotational cover cropping practices. The experiment was laid out as a split-plot arrangement in a randomized complete block design with 4 replicates. Tillage treatments (CT and NT) were applied on the main plots which measured 8 × 18 m while crop rotation treatments were applied in the subplots which measured 8 × 6 m. The rotation treatments were maize-fallow-maize (MFM), maize-wheat-maize (MWM) and maize-oat-maize (MOM). Weed control in NT plots involved preplant application of glyphosate to control mainly the grass weeds while post emergence weed management was done using Atrazine (485 atrazine and 15 g l-1 triazines). Initial weed control in CT plots was achieved through ploughing to a depth of 20 cm followed by disking while post emergence weed iii management was done by hand hoeing. Soil parameters measured were; (i) particulate organic matter (POM), soil organic carbon (SOC), total nitrogen (TN), pH and electrical conductivity (EC), (ii) soil bulk density (b), moisture at field capacity (FC), aggregate mean weight diameter (MWD) determined by fast wetting (FW), slow wetting (SW), mechanical breakdown by shaking (MB) and the stability index (SI), (iii) soil microbial biomass C (MBC) and N (MBN), mineralizable N (MN), soil respiration (SR), and dehydrogenase enzyme activity (DHEA). No-till increased POM and TN compared to CT in Lenye and Burnshill, respectively. The MWM and the MOM rotations increased TN relative to the MFM rotation in Lenye. The MWM and MOM rotations enhanced SOC relative to MFM in all sampled soil depths at Burnshill and similar observations were made under MOM rotation in the 5-20 cm depth in Lenye. The MWM and MOM rotations tended to depress soil pH relative to the MFM rotation in both sampled soil depths in Lenye while NT reduced soil pH relative to CT on the surface soil layer in Burnshill. Soil EC and pH varied with depth across tillage practices but both parameters remained within the ideal range for successful crop production over the study period. Soil stability index (SI) and aggregate MWD determined by FW, SW and MB were higher in Lenye compared to Burnshill. The MOM rotation enhanced the SI relative to MFM and MWM rotations at both sites. Scanning electron microscope (SEM) showed that more organic C was incorporated into the soil under NT and MOM rotation compared to CT and MFM rotation which had few organic coatings on the soil particles. Microbial properties varied with plant biomass input as influenced by tillage and type of rotational cover crop at both sites. Like in other past studies, NT showed higher levels of MBC, MBN, NM and SR at the soil surface layer compared to CT in Burnshill. No till increased MN iv relative to CT in both sampled soil depths in Lenye and resulted in higher DHEA compared to CT in Burnshill. The MOM rotation increased MBC, MBN, MN relative to MFM rotation especially within surface soil layer. Similar observations were made with respect to MN and SR in both sampled soil layers at Lenye. By contrast, the DHEA was higher under the MFM relative to the MWM and MOM rotations in Lenye but similar under the MFM and MOM rotations in Burnshill. Maize grain yield was not affected by both tillage and crop rotations but varied with cropping season. Comparable grain yields observed under the two tillage practices with similar fertilizer application rates indicated the advantage of NT over CT in saving on labour costs in maize production without compromising yields. High plant biomass retention under NT relative to CT contributed to high soil N and P levels under the former compared to the latter tillage practice especially on soil surface layer at both study sites. Principal component analysis (PCA) revealed that soil chemical and biological parameters closely linked to organic matter, namely SOC, MN, MBC and MBN showed the highest sensitivity to tillage and crop rotation treatments. Soil aggregate MWD determined by SW and b were the physical parameters which were highly altered by agronomic management practice. The MWM and MOM rotations were clustered together and clearly separated from the MFM rotation and this observed trend only applied to the 0-5 and 5-20 cm depths in Lenye site only. No till, MWM and MOM rotations enhanced POM, SOC and TN relative to CT and MFM rotation suggesting these practices have greater potential to improve soil chemical properties compared to intensive tillage and maize monoculture based production practices. Reduced soil b under MOM rotation and improved SI under NT compared to MFM and CT, respectively v indicate that these practices have the potential to improve degraded soils. Although not significantly different, NT values for MBC, MBN, MN, SR and DHEA were higher compared to CT indicating the potential of the practice to improve soil biotic activity relative to conventional tillage practices. No till enhanced surface soil nitrate N and extractable P compared to CT at both sites revealing the long-term potential of NT in improving the supply of these essential plant nutrients compared to CT. Principal component analysis showed that SOC, MN, K, P, MBC, MBN, soil aggregate MWD determined by SW and b were the most sensitive parameters to tillage and crop rotations. Therefore, these parameters could constitute the minimum data set for assessments of the impact of selected CA practices on soil quality attributes.
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