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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.
21

Synergistic potententials and isolation of bioactive compounds from the extracts of two helichrysum species indigenous to the Eastern Cape province

Aiyegoro, Olayinka Ayobami January 2010 (has links)
Helichrysum longifolium and H. pedunculatum belong to the Astereceae family and are used extensively in folkloric medicine in South Africa to manage stress-related ailments and as dressings for wounds normally encountered in circumcision rites, bruises, cuts and sores. The in vitro antibacterial time-kill studies, the synergistic potentials, the phytochemical screenings and antioxidant potentials as well as the isolation of the bioactive compounds from the extracts of these two plants were carried out in this study. The in vitro antibacterial activities and time kill regimes of crude extracts of H. pedunculatum was assessed. The extracts was active against both Gram positive and Gram negative bacteria tested at a concentration of 10 mg/ml. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.1 – 35 mg/ml. The average log reduction in viable cell count in time kill assay ranged between 0.17 Log10 to 6.37 Log10 cfu/ml after 6 h of interaction, and between 0.14 Log10 and 6.99 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC of the extract. The effect of the aqueous extract was only bacteriostatic on both reference and environmental strains and the clinical isolates were outrightly resistant to aqueous extract. This is worrisome and this could be one reason why, there is an incidence of high death rate resulting from circumcision wounds infection even after treating such wounds with H. pedunculatum leaf. In vitro antibacterial time kill studies of extracts of H. longifolium was assessed. All test bacteria were susceptible to the methanol extract, while none was susceptible to the aqueous extract. Two of the test bacteria were susceptible to the ethyl acetate extract, while ten and seven were susceptible to the acetone and chloroform extracts respectively at the test concentration of 5 mg/ml. The minimum inhibitory concentrations (MICs) ranged between 0.1 and 5.0 mg/ml, while minimum bactericidal concentrations (MBCs) ranged between 1.0 and >5 mg/ml for all the extracts. Average log reductions in viable cell counts for all the extracts ranged between 0.1 Log10 and 7.5 Log10 cfu/ml after 12 h interaction at 1 × MIC and 2 × MIC. Most of the extracts were rapidly bactericidal at 2 × MIC achieving a complete elimination of most of the test organisms within 12 h exposure time. The effect of combinations of the crude extracts of H. pedunculatum leaves and eight antibiotics was investigated by means of checkerboard and time-kill methods. In the checkerboard method, synergies of between 45.83-56.81 percent were observed and this is independent of Gram reaction, with combinations in the aqueous extract yielding largely antagonistic interactions (18.75 percent). The time kill assay also detected synergy that is independent of Gram reaction with a ≥ 3Log10 potentiation of the bactericidal activity of the test antibiotics. We conclude that the crude leaf extracts of H. pedunculatum could be potential source of broad spectrum antibiotics resistance modulating compounds. The interactions between crude extracts of H. longifolium in combination with six first-line antibiotics using both the time-kill and the checkerboard methods were carried out. The time-kill method revealed the highest bactericidal activity exemplified by a 6.7 Log10 reduction in cell density against Salmonella sp. when the extract and Penicillin G are combined at ½ × MIC. Synergistic response constituted about 65 percent, while indifference and antagonism constituted about 28.33 percent and 6.67 percent in the time kill assay, respectively. The checkerboard method also revealed that the extracts improved bactericidal effects of the antibiotics. About 61.67 percent of all the interactions were synergistic, while indifference interactions constituted about 26.67 percent and antagonistic interactions was observed in approximately 11.66 percent. The in vitro antioxidant property and phytochemical constituents of the aqueous crude leaf extracts of H. longifolium and H. pedunculatum was investigated. The scavenging activity on superoxide anions, DPPH, H2O2, NO and ABTS; and the reducing power were determined, as well as the flavonoid, proanthocyanidin and phenolic contents of the extracts. The extracts exhibited scavenging activity in all radicals tested due to the presence of relatively high total phenol and flavonoids contents in the extracts. Our findings suggest that H. longifolium and H. pedunculatum are endowed with antioxidant phytochemicals and could serve as a base for future drugs. Bioactivity-guided fractionation of the leaves of H. longifolium and H. pedunculatum yielded two known compounds. From the n-hexane fraction of H. longifolium a compound was isolated (Stigmasterol) and from the ethyl acetate fraction of H. pedunculatum another compound (β-sitosterol) was isolated. The compounds were isolated and identified using various techniques. The antimicrobial, anti-inflammatory, antioxidant, analgesic and anti-pyretic activities of these compounds have been reported in literatures. In general, the experiments and tests conducted in this study appear to have justified the folkloric medicinal uses of H. longifolium and H. pedunculatum for the treatment of stress related ailments and wound infections and make a substantial contribution to the knowledge base of the use of herbal medicine for the treatment of the microbial infections.
22

The ecophysiology of selected coastal dune pioneer plants of the Eastern Cape

Ripley, B S January 2002 (has links)
Understanding the mechanisms and adaptations that allow only certain species to thrive in the potentially stressful foredune environment requires a knowledge of the basic ecophysiology of foredune species. Ecophysiological measurements were conducted on the foredune pioneer species Arctotheca populifolia (Berg.) Norl., Ipomoea pes-caprae(L.) R. Br. and Scaevola plumieri (L.) Vahl. and showed significant differences among species with respect to the physiology associated with biomass production, water and nutrient relations. Differences related to CO₂ assimilation included differences in photosynthetic and respiratory rates, susceptibility to light stress and leaf and stem non-structural carbohydrate concentrations. These resulted in differences in primary production rates of shoots. Mechanisms leading to the differences in CO₂ assimilation among species included differences in stomatal behaviour, carboxylation efficiencies, efficiencies of utilisation of incident photosynthetic photon flux density (PPFD) and rates of ribulose-1,6-bisphosphate (RuBP) regeneration. Correlated with differences in photosynthetic capacity were differences in chlorophyll contents but not differences in leaf nitrogen content. Differences in interspecific stomatal behaviour resulted in significantly different transpiration rates which in combination with differences in assimilation rates resulted in differences in water-use efficiency. The absolute amounts of water transpired, although significantly different among species, were moderate to high in comparison with species from other ecosystems and were typical of mesophytes. Transpiration rates in combination with plant hydraulic conductances and soil water availability resulted in leaf water potentials that were not very negative and none of the investigated species showed evidence of osmotic adjustment. The volume of water transpired by each of the species per unit land surface area was estimated from the relationship between abiotic factors and plant water loss. These relationships varied among species and had varying degrees of predictability as a result of differences in stomatal behaviour between the three species. The water requirements of A. populifolia and S. plumieri were adequately met by the water supplied by rainfall and the water stored in the dune sands. It was therefore not necessary to invoke the utilisation of ground water or the process of internal dew formation to supply sufficient water to meet the requirements. However, I. pes-caprae despite its lower transpiration rates and due to its higher biomass, lost greater volumes of water per unit dune surface area than either A. populifolia or S. plumieri. This resulted in periods of potential water limitation for I. pes-caprae. Incident light was the most important determinant of leaf photosynthetic CO₂ assimilation and transpiration, particularly as a linear relationship between incident PPFD and atmospheric vapour pressure deficit (VPD) could be demonstrated. Whole plant photosynthetic production by S. plumieri was shown to be light limited as a result of mutual shading despite high incident and reflected PPFD occurring in the foredune environment. The leaf hair-layer of A. populifolia was shown to be important in reducing transmitted UV and hence reducing photoinhibition but it also caused reduced transpiration rates because of the thicker boundary layer and thus increased leaf temperatures. The nutrient content of above-ground plant parts of the investigated species were typical of higher plants despite the low nutrient content measured for the dune soils. With the possible exception of nitrogen the nutrient demand created by above-ground production was adequately met by the supply of nutrients either from sand-water or from aquifer-water transpired by the plants. Differences in the volumes of water transpired, and hence the quantity of nutrients potentially taken up via the transpiration stream, resulted in interspecific differences in above-ground plant macronutrient content. The reallocation patterns of nutrients differed both between the various nutrients measured and interspecifically. Standing biomass and the density of plants per unit land area was low in comparison to that of other ecosystems and was different among investigated species. This may be important in maintaining the adequate supply of resources (water, nutrients and light). As a result of the interspecific differences in biomass when production was expressed per unit land surface area the resultant productivity was not dissimilar among species. Productivity was high when comparisons were made with species from other ecosystems. No single resource (water, nutrients or light) could be identified as the controlling factor in the foredune environment and a combination of both resource stress and environmental disturbance are likely to be involved. Physiology, production, growth and growth characteristics conveyed certain adaptive advantages to these species in respect to both resource stress and environmental disturbance. Interspecific differences in these adaptations can be used to offer explanations for the observed microhabitat preferences of the three investigated species. Furthermore features common to all three species offer some explanations as to why these species and not others are able to inhabit the foredunes.
23

Modelling plant water use of the grassland and thicket biomes in the eastern cape, South Africa: towards an improved understanding of the impact of invasive alien plants on soil chemistry, biomass production and evapotranspiration

Gwate, Onalenna January 2018 (has links)
It is imperative to understand the strong coupling between the carbon capture process and water use to sustainably manage rangelands. Woody encroachment is undermining rangelands grass production. Evapotranspiration (ET) highlights the links between ecosystem carbon capture process and water use. It forms the biggest flux of the hydrological cycle after precipitation yet it is not well understood. The Grassland and the Albany Thicket (AT) biomes in the Eastern Cape, South Africa, provide an interesting space to study the dynamics in rangelands biomass production and the associated water use. Therefore, the main purpose of this study was to contribute towards management of rangelands by understanding the dynamics in rangeland grass production and water use. To achieve this aim, the impact of Acacia mearnsii, an invasive alien plant, on soil chemical properties and rangelands grass production was investigated. This was achieved by analysing the biophysical attributes of A. mearnsii as they related to grass production. Secondly, selected soil variables that could be used as a prognosis for landscape recovery or deterioration were evaluated. In addition, aboveground grass biomass was measured in areas cleared of A. mearnsii and regression equations were prepared to help model aboveground grass biomass in areas cleared of A. mearnsi. The thesis also explored dynamics in water vapour and energy fluxes in these two biomes using an eddy covariance system. Consequently, water vapour and energy fluxes were evaluated in order to understand landscape water use and energy partitioning in the landscape. The study also tested the application of Penman-Monteith equation based algorithms for estimating ET with micrometeorological techniques used for validation. Pursuant to this, the Penman- Monteith-Leuning (PML) and Penman-Monteith-Palmer (PMP) equations were applied. In addition, some effort was devoted to improving the estimates of ET from the PMP by incorporating a direct soil evaporation component. Finally, the influence of local changes in catchment characteristics on ET was explored through the application of a variant of the Budyko framework and investigating dynamics in the evaporative index as well as applying tests for trends and shifts on ET and rainfall data to detect changes in mean quaternary catchment rainfall and ET. Results revealed that A. mearnsii affected soil chemical properties and impaired grass production in rangelands. Hence, thinning of canopies provided an optimal solution for enhanced landscape water use to sequestrate carbon, provide shade, grazing, and also wood fuel. It was also shown that across sites, ET was water limited since differences between reference ET and actual ET were large. ET was largely sensitive to vapour pressure deficit and surface conductance than to net radiation, indicating that the canopies were strongly coupled with the boundary layer. Rangeland ET was successfully simulated and evaporation from the soil was the dominant flux, hence there is scope for reducing the so-called ‘unproductive’ water use. Further, it was shown that the PML was better able to simulate ET compared to the PMP model as revealed by different model evaluation metrics such as the root mean square error, absolute mean square error and the root mean square observations standard deviation ratio. The incorporation of a soil evaporation component in the PMP model improved estimates of ET as revealed by the root mean square error. The results also indicated that both the catchment parameter (w) and the evaporative index were important in highlighting the impacts of land cover change on ET. It was also shown that, despite changes in the local environment such as catchment characteristics, global forces also affected ET at a local scale. Overall, the study demonstrated that combining remote sensing and ground based observations was important to better understand rangeland grass production and water use dynamics.
24

The effect of geography, cultivation and harvest technique on the umckalin concentration and growth of pelargonium sidoides (Geraniaceae)

White, Andrew Graeme January 2007 (has links)
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.
25

Generating guidance on public preferences for the location of wind turbine farms in the Eastern Cape

Hosking, Jessica Lee January 2012 (has links)
There is consensus that Eskom, South Africa’s main energy supplier, needs to expand its energy generating capacity in order to satisfy the growing demand for electricity, but there is less agreement on how it should do this. The existing supply is heavily reliant on thermal generation using coal, but the combustion of fossil fuels for electricity generation may contribute to climate change because it causes harmful greenhouse gases to be emitted into the atmosphere. This emission is something South Africa has committed itself to reducing. One way of achieving this is by the adoption of cleaner technologies for energy generation. One of these technologies is harnessing wind energy. The problem with harnessing wind energy is where to locate the turbines to harness the wind because these turbines ‘industrialise’ the environment in which they are located. They are a source of increased noise, a visual disturbance, cause increased instances of bird and bat mortality and the destruction of flora or the naturalness of the landscape in the areas in which they are located. The residents located near wind farm developments are most negatively affected and bear the greatest cost in this regard. A proper social appraisal of wind turbine projects would have to take this cost into account. Before such developments are approved there should be an assessment made of the impact on the residents, these impacts should be incorporated into the cost-benefit analysis. The negatively affected residents should also be compensated. The objective of this study was not to undertake a cost-benefit analysis of such a wind farm proposal, but to estimate the negative external cost imposed on nearby residents of such an industry, and thereby calculate appropriate compensation to be paid to these residents. Quantifying preferences for proposed, but not-yet developed, wind farms may be done by applying non-market valuation techniques, e.g. through one of the stated preference methodologies, such as a discrete choice experiment. The selected study site for providing guidance was one where Red Cap Investments Pty (Ltd) has proposed the development of a wind farm - in the Kouga local municipality. The basis for drawing conclusions was the analysis of the response samples of two groups of Kouga residents, distinguished by socio economic status; 270 from each group, 540 in total. The methodology applied to analyse the responses was a discrete choice experiment. The questionnaire administered included attitude, knowledge and demographic questions as well as a choice experiment section. The choice experiment section of the questionnaire required that the respondents choose between two different hypothetical onshore wind energy development scenarios and a status quo option. The hypothetical scenarios comprised different levels of wind farm attributes. The attributes included in the experiment were determined by international studies and focus group meetings. These attributes were: distance between the wind turbines and residential area, clustering of the turbines (job opportunities created by the wind farm development for underprivileged respondent group), number of turbines and subsidy allocated to each household. Three different choice experiment models were estimated for each socio-economic group: a conditional logit (CL), nested logit (NL) and a random parameters logit (RPL) model. It was found that, in the affluent respondent group, the simpler CL model provided the best fit. In the underprivileged respondent group, the RPL model, with the number of jobs created by the wind farm project as a random parameter1, explained by the gender of the respondent, provided the best fit. The estimated models identified distance as an important factor in both sampled respondent groups. Both respondent groups preferred that the wind farm be located further away from their residential areas. In addition to distance, the underprivileged respondent group also valued new job opportunities as an important determinant of choice. The affluent respondent group were very sensitive to densely clustered turbines but were almost indifferent between two of the effects coded levels of the clustering attribute “moderately close together” and “widely spaced apart”. Welfare estimates for the significant attributes in each socio-economic group were computed from the best fit models. Table 1 shows the resulting willingness to accept (WTA) compensation measures for distance in both socio-economic respondent groups.
26

Investigation of antidiabetic properties, mechanisms of action and toxicology of Strychnos Henningsii (GILG) bark

Oyewole, Oyedemi Sunday January 2011 (has links)
The apparent reversal of trend from modern drugs to herbal medicine is partly due to the fact that synthetic drugs have always shown adverse reactions and other undesirable side effects. Hence, the use of medicinal plants for the treatment of diseases such as diabetes is very common especially in the rural areas. Majority of these plants are used based on the experience and indigenous knowledge without identification of the therapeutic agents. There is enormous wealth of medicinal plants in the world yet many of them have not been discovered or studied scientifically to substantiate their ethno-medicinal usages. Ethnobotanical study has been the method often used to search for locally important plant species for the discovery of crude drugs with low side effects. An ethnobotanical survey was conducted on the medicinal plants commonly used for the management of diabetes mellitus in Nkonkobe Municipality, Eastern Cape of South Africa. Information was obtained through structured questionnaire administered to traditional healers and herbalists in the region. The study revealed 15 species of plants belonging to 13 families. Strychnos henningsii and Leonotis leonorus among others were repeatedly mentioned by the traditional healers as the two mostly used plants for the management of diabetes mellitus. The infusion and decoction of the roots, leaves and barks of these plants are the methods of preparation. The antioxidant potential of aqueous bark extract of S. henningsii was investigated both in vivo and in vitro using spectroscopic method. The antioxidant activity of the extract against hydrogen peroxide (H2O2), 2,2′-azinobis[3-ethylbenzothiazoline6-sulfonic acid] diammonium salt (ABTS), as well as reducing power was concentration dependent. The extract exhibited lower and average scavenging activities against 1,1diphenyl2picrylhydrazyl (DPPH) and nitric oxide (NO) radicals with IC50 value of 0.739 and 0.49 mg/ml respectively. The administration of the plant extract at 250, 500 and 1000 mg/kg significantly increased the activities of the antioxidant enzymes in the hepatotoxic rats induced with carbon tetrachloride. On the other hand, the stem bark extract had lower effect on lipid peroxidation level except at the dose of 250 mg/kg. The effect of oral administration of S. henningsii extract was evaluated in normal Wistar rats for 28 days. The observed result indicated non- toxic effect of sub-acute administration of plant extract to the animals except at certain doses. This is because, there was no apparent damage to some haematological and biochemical parameters used in assessing organ specific toxicity. However, the alterations observed on platelet, white blood cells and its differentials imply parameter and dose selective toxicity when repeatedly consumed on daily basis at the doses investigated. This study also investigated the antidiabetic activities of the extract at the doses of 125, 250 and 500 mg/kg body weight in diabetic rats induced with streptozotocin -nicotinamide for 15 days. The extract appreciably (P <0.05) reduced the blood glucose level, feed and water intake while the best result was obtained at 250 mg/kg. Similarly, the level of triacylglycerol at the three doses investigated was significantly decreased. In addition, the glucose tolerance was reduced to near normal level after 90 min at certain doses. The clinical significance of the extract on some biochemical and haematological parameters lessen both hepatic and renal damages. Anaemic condition in diabetic animals was also improved after plant extract administration. However, no significant effect was observed in white blood cells and some of its differentials. The extract demonstrated strong glucose utilization in 3T3-L1 cells with a response of 278.63 percent of the control at 12.5μg/ml while that of Chang liver cells was 103.54 percent. The cytotoxicity result revealed non toxic effects of the extract to both cell lines. Treatment of 3T3 L1 cells with the extract did not reduce lipid accumulation. The extract inhibited the activity of α- glucosidase and α- amylase in a concentration dependent manner with IC50 values of 38 μg/ml and 60.9 μg/ml respectively. The percentage protein antiglycation of S. henningsii was 18.4, 38.2 and 61.2 perceent for 0.25, 0.5 and 1 mg/ml respectively while aminoguanidine a known inhibitor of protein glycation was 87.2 percent at 1 mg/ml. The FRAP assay values of the extract was 357.05 μmol Fe (II)/g. The findings from this study support the folkloric usage of this plant for the management of diabetes mellitus in the region.
27

Assessment of plants used for the treatment of cattle wounds and myiasis in Amatola Basin, Eastern Cape Province, South Africa

Soyelu, Oluseyi Temitope January 2010 (has links)
No description available.
28

Prevalence and pathogenicity of vibrios in treated final effluents of selected wastewater treatment plants in the Amathole District Municipality of Eastern Cape Province of South Africa

Badela, Andiswa Unathi January 2014 (has links)
Waterborne diarrhoeal infections continue to be a major health setback in developing countries, especially in rural areas which lack adequate supply of portable water and sanitation facilities. Globally, waterborne diarrhoeal infections occur with an estimated mortality rate of 10–25 million deaths per year, 95% of which are children under the age of 5 years. The Vibrio species is one of the major groups of enteric pathogens that are responsible for diarrhoeal infections. Many strains of these bacterial species continue to cause epidemics of diarrhoea throughout the world. In this study, the prevalence of Vibrio pathogens in wastewater final effluents was assessed. Wastewater final effluent and discharge point samples were collected monthly between September 2012 and August 2013. All samples were collected aseptically using sterile 1 L Nalgene bottles containing 0.5 ml of sterile sodium thiosulphate solution and transported on ice to the laboratory for analyses within 6 h of collection. The membrane filtration method was used for enumeration of presumptive Vibrio densities on thiosulfate citrate bile salt (TCBS) agar plates. Polymerase chain reaction (PCR) was then used to confirm the identities of the presumptive Vibrio species using the species-specific primers. The confirmed isolates were further subjected to molecular characterization to confirm their respective pathotypes. Presumptive Vibrio densities varied from 0 to 2.11 × 102 cfu/100 ml. Out of 300 confirmed Vibrio isolates; 13.3% (40/300) were Vibrio fluvialis, 22% (66/300) were confirmed to be Vibrio parahaemolyticus, and 24.7% (74/300) proved to be Vibrio vulnificus, and 40% (120/300) were other Vibrio species which were not assessed for in this study. The strains of Vibrio fluvialis were found to exhibit 100% resistance to Polymixin and Tetracycline. However, Gentamicin was active against all the three Vibrio species selected for the purpose of this research. The recovery of Vibrio species in the discharged effluents throughout the sampling period even in adequately disinfected effluents is not acceptable considering the fact that Vibrio is a pathogenic bacterium. The findings of this study underline the need for constant monitoring of the microbiological qualities of discharged effluents and might also be suggestive for a review of the disinfection methods used at the treatment works.
29

Studies in the plant ecology of Fern Kloof near Grahamstown

Seagrief, S C January 1950 (has links)
The area studied at Fern Kloof, near Grahamstown, consists of a strip of vegetation approximately 260 yds. long and 50 yds. wide, in which there are two communities: 1) indigenous forest 2) exotic Pine forest (which has only one tree species Pinus pinaster). Throughout the thesis this species is referred to as the pine. The object of the investigation has been to determine whether these communities are natural or not. This has involved a study of the floristic composition, the life forms and the structure of the plant communities. In addition, various soil and environmental factors have been studied.
30

Botanical inventory and phenology in relation to foraging behaviour of the Cape honeybees (Apis Mellifera Capensis) at a site in the Eastern Cape, South Africa / The ecology of honey plants in the Eastern Cape

Merti, Admassu Addi January 2003 (has links)
From an apicultural point of view the Cape fynbos is under-utilised and our knowledge of its utilization by the Cape honeybees is incomplete. The key aim of this study was to test the hypothesis that the Cape honeybees utilize the fynbos species as the preferred source of nectar and pollen. Subsidiary aims included distinguishing vegetation communities in the area, identifying pollen and nectar sources, the relationship between brood population and seasonal pollen collection patterns, examining the effect of meteorological factors on pollen collection. The study site was on Rivendell Farm within the Eastern Cape Albany district: an area of high species richness. A checklist of vascular plant species was produced revealing 97 families, 271 genera and 448 species. A classification by two-way indicator species (TWINSPAN) recognized seven vegetation communities: Forest, Bush clumps, Acacia savanna, Grassland, Grassy fynbos, Fynbos and Shrubland. Direct field observations of the foraging of Cape honeybees identified 54 nectar and pollen source plant species. Honeybee pollen loads trapped from four colonies of hives identified 37 pollen source plants of which Metalasia muricata, Eucalyptus grandis, Eucalyptus camaldulensis, Erica chamissonis, Helichrysum odoratissimum, Helichrysum anomalum, Crassula cultrata and Acacia longifolia were the predominant pollen source plants. It was also found that 60% of pollen yield derived from fynbos vegetation. The pollen source plants came from both Cape endemic and from nonendemic species. Thus we reject the hypothesis that Cape honeybees selectively forage fynbos species as a preferred source of pollen and nectar. The examination of the effect of temperature, wind-speed and temperature on pollen collection activity of honeybees revealed that: a temperature range of between 14°C to 26°C was optimal for pollen collection; wind speeds of up to 4m/s were conducive for pollen collection; relative humidity was found to have no significant influence on pollen collection. Pollen collection and brood rearing patterns are positively correlated with flowering intensities, but we found in our Eastern Cape study site that brood rearing was not limited to the spring flowering season but did extend to the end of summer. In order to determine the available nectar yield of common plant species hourly secretion of nectar volumes was measured for 24 hours to determine the variation of available nectar during different times of the day. In all nectar producing species the nectar volume was high in the early morning and declined as the day progressed. We found that the volume of available nectar was affected by prevailing temperature and humidity around the flowers.

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