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

Small holder farmers' perceptions, host plant suitability and natural enemies of the groundnut leafminer, Aproaerema modicella (Lepidoptera: Gelechiidae) in South Africa / Anchen van der Walt

Van der Walt, Anchen January 2007 (has links)
Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
2

Small holder farmers' perceptions, host plant suitability and natural enemies of the groundnut leafminer, Aproaerema modicella (Lepidoptera: Gelechiidae) in South Africa / Anchen van der Walt

Van der Walt, Anchen January 2007 (has links)
Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
3

Small holder farmers' perceptions, host plant suitability and natural enemies of the groundnut leafminer, Aproaerema modicella (Lepidoptera: Gelechiidae) in South Africa / Anchen van der Walt

Van der Walt, Anchen January 2007 (has links)
Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2008.
4

Smallholder farmers' perceptions on climate variability in relation to climatological evidence in the Molemole Municipality (Limpopo Province) South Africa

Rapholo, Maropene Tebello Dinah January 2018 (has links)
Thesis (MSc. (Geography)) -- University of Limpopo, 2018 / In spite of the widespread scientific debate on the impacts of climate variability, not much is known about smallholder farmers’ perceptions towards climate variability and the impacts thereof on their agricultural practices. This is especially true for smallholder farmers in Sub-Saharan Africa in general and South Africa in particular. Literature contends that an understanding of the farmers’ perceptions of climate change and variability is indispensable for effective policy formulations and adaptive strategies. This current study posits that discrepancies between farmer perceptions and climatological evidence will negatively impact on farmer adaptation options and outcomes. The objectives of the study were to; (1) assess climate variability in Molemole Local Municipality, Limpopo Province, (2) investigate farmers’ perceptions of climate variability, (3) compare farmers’ perceptions of climate variability with climatological data and (4) appraise farmers’ adaptive strategies to climate variability. A total of 125 farmers from Botlokwa Village participated in the study. The village was selected because it is the largest village in the municipality and it comprises mainly of rural farmers that are involved in rain-fed subsistence agriculture. In addition, the village receives limited government intervention and is in close proximity to a functional climate station (Polokwane Airport Weather Station). Based on purposive sampling, focus group discussions and a three-part closed ended questionnaire was administered to the farmers. Mean annual temperature and rainfall data (30 years) was used to assess climate variability in the study area. Farmers’ perceptions to climate variability was assessed using descriptive statistics based on summary counts of the responses with Statistical Package for Social Science (SPSS) program. Logistic regression analysis was used to compare differences in perception (mean responses). Comparison of farmers’ perceptions of climate variability against climatological evidence was restricted to mean annual temperature and rainfall data over the past 5 – 10 years). To appraise farmers’ adaptive strategies, the Adaptation Strategy Index (ASI) and the Weighted Average Index (WAI) were employed. vi Farmers’ perceptions of climate variability were consistent with recorded meteorological data. Based on the ASI and WAI computations, use of indigenous knowledge systems (IKS) and crop management approaches were highly important adaptation strategies while the use of insurance and subsidies were least employed by the farmers. The results from the study also showed that the age of the household head, gender, level of education, farming experience and access to information on climate variability were crucial factors in influencing the likelihood of farmers to perceive climate variability. Given the overwhelming dependence on IKS for weather forecast, and adaptation to climate variability, it is recommended that IKS take centre stage in government initiatives and policies on climate change and variability, especially for smallholder farmers in rural settings. Sensitisation on the use of technology such as cellular phones to receive weather forecast is also recommended.
5

Market participation of smallholder sunflower farmers in Sekhukhune District of Limpopo Province, South Africa

Mathagu, Hangwelani Tshilidzi January 2016 (has links)
Thesis (MSc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2016 / The study focused on the market participation of the smallholder sunflower farmers of Sekhukhune District in Limpopo Province of South Africa. A total of 100 smallholder sunflower farmers of Sekhukhune were randomly selected for the study. Data was gathered through the use of structured questionnaires with open-ended questions. The data was analysed using the Logistic Regression model on SPSS 26.0 (statistical package for social sciences). The probability of the smallholder sunflower farmers participating in markets was determined significantly by gender of household head, farm size, level of education, marketing experience, distance to the market, ownership of vehicle and stakeholder availability. Recommendations were made with regard to that of training, monitoring, funding, Government support, access to production land and the involvement of organizations with the smallholder sunflower farmers. Training should be provided for the smallholder sunflower farmers because farmers are always faced with new technology and market changes, there should be a budget that is put aside for the funding of the smallholder farmers, monitoring programs should be implemented in order to monitor the progress of the smallholder farmers, increased access to production land for farming, government support through financial and input support, smallholder farmers should get involved with organizations that can help them with training and funding, and the government should implement policies that are commodity based. Key words: smallholder farmers, market participation, Logistic Regression Model, sunflower, Limpopo province
6

Risk and vulnerability analysis of dryland agriculture under projected climate changes : adaptive response in South African summer rainfall areas

Kephe, Priscilla, Ntuchu January 2020 (has links)
Thesis (Ph.D. (Geography)) -- University of Limpopo, 2020 / Agriculture in South Africa, particularly in the summer rainfall areas, faces the challenge of optimal crop production in the face of climate change. Climate change scenarios for South Africa have been predicted to have a negative impact on agriculture particularly in the summer rainfall areas because of its dependence on climate variables. Within the context of the South African agricultural sector, it has become important to identify who and what is most vulnerable to impacts of climate change, so that support for adaptation can be targeted appropriately. The aim of this study was to assess the hazard of climate change in relation to the production of selected dryland crops, namely: sunflower, soybean, and groundnut in the summer rainfall areas and to model their vulnerability and response to climate change as well as to develop coping and adaptation strategies. A survey of 800 farmers was carried out in three agro-ecological zones of Limpopo and Free State. The population was purposively selected and were present for focus group discussions and questionnaire administration. Questions on agronomic practices, cost of production, climate change impact on productivity, coping and adaptation methods used in the face of climate change were asked. The response showed that farm production was not at the optimum, not only because of the influence of climate but as a result of the poor agronomic practices by the farmers. Following a factor analysis, 70% of the decline in crop yield was attributed to poor farming decisions. A further look at climatic factors affecting farmers indicated that frost with a 0.989 loading was the most climate extreme affecting most of the farmers. In order to buffer the effects of climate change, the farmers undertook various changes in their farm management and also received some support from the various governmental and non-governmental institutions. It was however, found that though there were policies in place for farmer support, such supports were not administered in a timely fashion and some support types were not adequate for the farmers. A correlation between the number of supports received and yields showed an increase in yield for farmers who received more than one type of support and with such variations evident across the agroecological zones. Physical modelling was conducted to model crop suitability based on downscaled data from the Special Report on Emissions Scenarios A2, (SRES A2) for the time periods centred on 2020, 2050 and 2080. The results showed areas which were not suitable for either soybean, sunflower or groundnut production in the future over time with some areas gaining and losing under different farm input regimes. To establish the effects of climate change on yield, a field experiment was carried out for two consecutive seasons and the results obtained were used to feed the AquaCrop crop simulation model to model the effects of climate change on yield under different management conditions.The results obtained from the survey, field experiments and climate indices guided the development of vulnerability indicators in a spatial manner. Using the socioeconomic and biophysical results, the vulnerability of the summer rainfall area was calculated. The results showed that areas in Limpopo, North West, Eastern Cape, and Northern Cape were the most vulnerable. Based on the types of adaptation options employed by farmers which included a change in planting dates, employing support from institutions, other sources of income, farming practices and recommendations for future adaptation, various scenarios were run in a crop simulation model to determine the cropping regimes suitable for the study area. Options included technology, on-farm management, out of farm management, human and social factors. The results indicated that coping and adaptation measures are place specific and the effects of a climate extreme are felt differently by different farming communities and farmers in the same community. It is hence recommended that the government in its policies towards alleviating the risk of farmers to climate change should look at site-specific options and not a one model fits all. Farmers should also play a role in enhancing their adaptive capacity as well. It is only when barriers are bridged and a proper network of communication established alongside resource provision, will there be a change in farmer’s attitude toward implementing suggested adaptation options. / University of Limpopo VLIR-IUC
7

DENSIDADE DE PLANTAS, COMPONENTES DO RENDIMENTO E QUALIDADE DE SEMENTES DE VARIEDADES CRIOULAS E COMERCIAIS DE MILHO

Wutzki, Raquel Márcia Modena 14 February 2014 (has links)
Made available in DSpace on 2017-07-25T19:30:46Z (GMT). No. of bitstreams: 1 Raquel M Modena Wutzki.pdf: 1108265 bytes, checksum: 95460fc6833be7f87bfb57b0ddae51e7 (MD5) Previous issue date: 2014-02-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Considering the actual tendency of increasing plant densities in corn crops and the lack of information about this issue on varieties used by smallholder farmers, in this research was assessed variations in plant density of corn and seed quality. The experiment was located in Imbaú, PR, trasition climate zone Cfa/Cfb, on crop season 2011/2012, using the landrace varieties Nutricional, Caiano, MPA and Composto and the commercial varieties BRS Sol da manhã® and BRS Missões®, on plant densities of 30, 40, 50, 60 and 70 thousand plants ha-1. Stem diameter of plants, ear height of corn, number of seed lines per ear, number of seeds in lines of the ear, number of seeds per ear, mass of a thousand grains and yield were determined in the assessments, besides seed germination, vigor and seed quality. There was interaction between varieties and cultivars for mass of a thousand seeds, seed germination and vigor and seed sanity. For most of varieties, plant densities of 30 and 40 thousand plants favored increasing of stem diameter, yield components and seed germination and decreased incidence of Penicillium spp e Fusarium spp. With the increasing of plant densities starting at 50 thousand plants ha-1, for all varieties, there were decreasing on stem diameter and increasing of lodging plants rate, with consequent increasing of incidence of diseases and decreasing of seed germination. On Caiano and Composto varieties, decreasing of seed germination may be related to the incidence of Fusarium spp. It is possible to conclude that increasing corn’s plant density causes decreasing of yield components, yield and seed quality for most of varieties and cultivars assessed, especially to plant densities of more than 30 thousand plants ha-1. For physiological parameter, the ideal is the utilization of 30 thousand plants ha-1 for variety Composto and cultivar BRS Misssões®, 40 thousand plants ha-1 for varieties Caiano and Nutricional and 50 thousand plants ha-1 for variety MPA and cultivar BRS Sol da Manhã®. Plant densities of 30 thousand to 50 thousand plants ha-1 present less incidence of Penicillium spp e Fusarium spp in all varieties and cultivars. / Considerando a tendência atual do aumento da densidade de plantas para o cultivo do milho e a restrição de informação sobre essa variável em variedades utilizadas pelo agricultor familiar, nessa pesquisa foram avaliadas variações da densidade das plantas de milho e a qualidade das sementes. O experimento foi conduzido em Imbaú, PR, zona de transição climática Cfa/Cfb, na safra 2011/12, utilizando as variedades crioulas de milho: Nutricional, Caiano, MPA e Composto e as variedades comerciais: BRS Sol da Manhã® e BRS Missões®, nas densidades de 30, 40, 50, 60 e 70 mil plantas ha-1. Para as avaliações foram determinados o diâmetro do colmo das plantas, a altura de inserção da espiga, os números de fileira por espiga, de sementes por fileira e de sementes por espiga, a massa de mil sementes e o rendimento, além da germinação, do vigor e da sanidade das sementes. Houve interação entre as variedades de milho para a massa de mil sementes, a germinação, o vigor e a sanidade das sementes. Para a maioria das variedades, as populações de 30 e 40 mil plantas favoreceram o aumento do diâmetro do colmo, dos componentes de rendimento e da germinação das sementes e reduziram as incidências de Penicillium spp e Fusarium spp. Para todas as variedades, com o aumento da densidade a partir de 50 mil plantas ha-1, houve a redução do diâmetro do colmo e o aumento da taxa de acamamento de plantas, com consequente aumento da incidência de doenças e redução da germinação das sementes. Nas variedades Caiano e Composto, a redução da germinação das sementes pode estar relacionada à incidência de Fusarium spp. É possível concluir que o aumento da densidade das plantas de milho causa redução dos componentes de rendimento, do rendimento e da qualidade das sementes, para a maioria das variedades avaliadas, especialmente para densidades superiores a 30 mil plantas ha-1. Em termos fisiológicos o ideal é a utilização de 30 mil plantas ha-1 para a variedade crioula Composto e a variedade comercial BRS Missões®, de 40 mil plantas ha-1 para as variedades crioulas Caiano e Nutricional e de 50 mil plantas ha-1 para a variedade crioula MPA e para a variedade comercial BRS Sol da Manhã®. Populações de 30 mil até 50 mil plantas ha-1 apresentam as menores incidências de Penicillium spp e Fusarium spp para todas as variedades.
8

Organic manure effects on selected soil properties, water use efficiency and grain yield of sunflower

Mokgolo, Matome Josphinos January 2016 (has links)
MSCAGR (Soil Science) / Department of Soil Science / The application of organic manures as alternatives to reduce the use of mineral fertilizers is considered a good agricultural practice for smallholder farmers. However, the effect of organic manure on soil properties and crop yield depends upon its application rate and chemical composition. Climatic seasonal variability within the study area could adversely affect crop production. The amount of rainfall and temperature are among the most important factors that determines crop production. This field experiment was carried out during the 2013/2014 and 2014/2015 cropping seasons at the University of Venda experimental farm which is located about 2 km west of Thohoyandou town in the Vhembe District, Limpopo Province. The main objective of this study was to determine the effect of three types of organic manure (cattle, poultry and their combination (1:1)) on yield and water use efficiency of sunflower (Helianthus annuus L.) and selected soil physical and chemical properties under rainfed conditions. The experiment was a randomized complete block design (RCBD) with four treatments and four replications (control (C0), cattle manure (CM), poultry manure (PM) and their combination (CM + PM)). All organic manures were applied 21 days before planting at a rate equivalent to 20 t ha-1. The manures were incorporated in the soil using a hoe to an approximate depth of 10 cm. Crop water use (WU) and water use efficiency (WUE) were determined using the water balance equation. Rainfall was measured using three standard rain gauges installed on the experimental site. Change in soil moisture storage was determined by monitoring soil moisture content weekly using a neutron water meter (NWM), calibrated on the experimental site. Data on sunflower dry matter and leaf area index (LAI) was collected at flower bud stage, flowering stage and at grain maturity stage. Plant height and stem girth were also determined at the same developmental stages. Grain yield was measured at physiological maturity. xv Analysis of variance (ANOVA) was carried out using SPSS software. Due to seasonal variability encountered during the two cropping seasons, particularly in terms of rainfall, further analysis of two factors (viz. cropping season and organic manure) and their interaction were performed. The differences between treatment means were separated using the least significant differences (LSD) procedure. The results showed that organic manure application had no significant effect on soil physical properties. Poultry manure application resulted in lowest bulk density (BD) with a decrease of 32% in the top layer (0 – 20 cm) compared to control. Cattle manure + PM and CM application decreased BD in the top layer by 14% and 9% compared to control, respectively. Poultry manure and CM recorded almost the highest similar stable aggregate fractions at all soil depths. Poultry manure recorded the highest final infiltration rate and cumulative infiltration followed by CM and CM + PM. The control treatment retained the highest mean water content compared to other treatments at both field capacity (FC) and wilting point (WP). Cattle manure + PM and PM recorded the least mean water content among others at FC and WP respectively. This could be as a result of increased micropores by organic manure application on a clayey soil which allowed an ease movement of water that control treatment which had no manure application. Total N, Ca, and Zn were significantly different between treatments in the first cropping season while K, Na, CEC and Zn were significantly different in second cropping season. pH recorded no significant difference in all treatments in both cropping seasons. CM + PM recorded the highest OC at top layer (0 – 20 cm) in both cropping seasons compared to other treatments. Dry matter yield and LAI at flower bud, flowering and maturity stages increased with the application of different manures compared to the C0. Organic manure application showed a significant (p<0.05) effect on dry matter at all growth stages in the second cropping season. Organic manure had a significant effect on LAI only at flower bud stage of the first cropping season, with PM and CM + PM recording the highest similar value of 1.31. The manure xvi application also showed a significant (P<0.05) effect on plant height and stem girth at all growing stages in the second cropping season, whereas in the first cropping season the significant effect was only in the flower bud stage for both parameters. Grain yield was significantly affected by the manure application in the second cropping season. Manure application in the second cropping season resulted in an increase in the grain yield compared to the first cropping season, except for PM where the grain yield decreased significantly by 167.92% from the first cropping season. Then high grain yield in the second cropping season could be as a result of high WUE reported. The manure application had a significant effect (p<0.05) on water use efficiency (WUE) in the second cropping season. The WUE recorded the highest values under CM and CM + PM treatments in second cropping season than in first cropping season, while PM recorded the highest WUE value in the first cropping season. Generally, organic manures used obtained higher grain yield and WUE compared to control. Keywords: Organic manure, smallholder farmers, sunflower and water use efficiency
9

DEVELOPMENT OF DESIGN CRITERIA AND OPTIONS FOR PROMOTING LAKE RESTORATION OF LAKE BOSOMTWE AND IMPROVED LIVELIHOODS FOR SMALLER-HOLDER FARMERS NEAR LAKE BOSOMTWE - GHANA, WEST AFRICA

Grace L Baldwin (7847804) 12 November 2019 (has links)
<p>The Lake Bosomtwe impact crater is located in the Ashanti region of Ghana, West Africa. The impact crater diameter from rim to rim is approximately 10.5 km wide with a lake located at the center. Three different districts touch the lake containing 155,000 hectacres of land. There are approximately 7,500 people from 24 villages, and 12 of those villages reside within walking distance of the lake shore. Within the last ten years, the lake has been subjected to overfishing and environmental degradation. The health of the lake has declined due to overfishing and algae blooms caused by improper fertilization rates. Because of these factors, residents of the area have been forced to transition to subsidence farming as their main vocation. According to the Ghana Statistical Service group, 97.6% of the population participates in some form of rural crop farming (Ghana Statistical Service, 2010). Experience with common practices such as crop rotation, fertilizer use, and erosion control is extremely limited. The lake has not been recommended for recreational use due to the excess runoff in the form of agrochemicals, liquid, and organic waste. Caged aquaculture and traditional fishing within Lake Bosomtwe is currently illegal.</p><p><br></p><p>A comprehensive Institutional Review Board (IRB) survey was developed for the six primary research questions to be examined. From these six research questions, 147 specific questions were developed. Three of the 147 questions were to obtain Global Positioning System (GPS) data for community households, pit latrines, and water wells or boreholes. This study sought to interview 10-15 farmers per village, for each of the 12 villages located along the shore of Lake Bosomtwe of their perspective on land use change/cover in the Lake Bosomtwe area, current farming practices, current water sanitation and hygiene practices, and current fishing practices. These surveys were collected in the form of oral responses, for which 118 small-holder farmers were interviewed. Of the participants surveyed, 66% were qualified to answer all questions, and 100% of participants completed the survey.</p><p><br></p><p>Some specific statistical tests were conducted based of market assessment survey. It was determined that no association between gender and level of education existed. Meaning, that female participants interviewed have just as many opportunities as male participants to pursue education beyond Junior High School (JHS). Yield averages between the villages on the north side of the lake with road access and villages on the southern portion of the lake with limited to no road access were determined to be significantly different. It was determined that road access does affect village yield. When comparing average usable yields between villages located on the northern side of the lake with road access or between villages on the southern side of the lake with limited to no road access, these results were not statistically significant. No significant difference in the scores for villages with road access on the northern side of the lake and villages with limited to no road access on the southern side of the lake existed. Therefore, road access does not affect village usable yield. Through statistical analysis an association was determined between people who practice bathing and washing in the lake and those who practice fishing as a form of livelihood.</p><p><br></p><p>Four decision matrices were created to prioritize the following items: Farm Components, technologies to showcase at an appropriate technology center, improved farming practices to showcase through Demonstration Plots, and extension outreach topics. The top three results for the Farm Components were: Appropriate Technology Center (ATC), Demonstration Plots, and a Micro-Credit Union. The top three technologies to showcase as part of the ATC are: PICS Bags, Moisture Meters, and Above-Ground Aquaculture. The three demonstration plots recommended terracing/erosion control, crop rotation, and cover crops. The highest priority extension outreach topics were: basic home/farm finance, improving health through washing stations, and post-harvest loss prevention. The top three priorities of each decision matrix will be the focus of further study, so that these topics can be developed and programs focusing on these needs can be implemented in collaboration with the community partners.</p>

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