Permeability changes in membranes of Protea neriifloia leaves during senescence were investigated. A complete preservative consisting of a-hydroxyquinoline sulphate (8-HQS), silver nitrate (AgN03), citric acid and sucrose was formulated by using different concentrations of the components. The % browning of the leaves, change in mass of the inflorescence and their water uptake over a period of 20 days was used as a measurement to determine the most effective concentrations. The results lead to the formulating of an effective preservative which can be used commercially. The preservative consists of 100 mg 8-HQS, 5 mg AgNo3, 100 mg citric acid. and 10 g sucrose, made up to 1 litre with distilled water. Scanning electron microscopy was used to investigate the effects of a complete preservative on protea leaves. The respiratory rate and water content of leaves from inflorescence in preservative and distilled water was determined and compared. The respiratory rate of leaves of inflorescence in preservative was considerably higher than that of the control. The preservative also resulted in the leaves having a better retention of their water...

Magister Artium - MA / This mini-thesis seeks to interrogate the interplay between memory and documentation in the process of exhibition-making by a looking at the preparation for and mounting of the exhibition, Museum. This will be achieved by looking at the institutional methodologies employed by the Museum in dealing with ex-residents of District Six, their memories and artefacts in the heritage practice of a Museum as a forum. This practice was put into effect as the District Six Museum engaged ex-residents of other locations of removal.

M.Sc. (Botany) / Please refer to full text to view abstract

Thesis (MScAgric)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Protea cut flowers are exported worldwide but the vase life of some species and cultivars is considerably shortened by post-harvest leaf blackening. Research has established carbohydrate depletion to be positively correlated with this disorder. Consequently, a study had been made of the carbohydrate status of various species and cultivars, as well as the effect of supplemental glucose (pre and post-storage) on leaf blackening. Glucose, fructose, sucrose and starch concentrations of various Protea species and cultivars held in water were measured at harvest, and again at leaf blackening initiation. All measured carbohydrates declined significantly in 'Carnival', 'Pink Ice' and 'Sheila'. In 'Cardinal' all carbohydrate concentrations decreased significantly, except the sucrose concentration in the inflorescence. 'Susara' and 'Ivy' had very high initial carbohydrate concentrations in the leaves which decreased significantly. The very high initial carbohydrate concentrations in the inflorescence of 'Ivy' declined significantly. 'Brenda' differed from the other cultivars and species in that glucose concentrations increased over time. Carbohydrate concentrations of most of the tested proteas declined significantly from harvest to the initiation of leaf blackening. This highlighted the dependence of the leaves and inflorescence on the carbohydrate reserves, further substantiating the carbohydrate depletion theory. The inflorescences were characterized by high fructose and glucose concentrations and low sucrose concentrations when compared to the leaves. It was hypothesized that glucose pulsing and cold storage at 1°C for three weeks would significantly reduce leaf blackening. 'Brenda', 'Cardinal', 'Carnival', 'Pink Ice', 'Susara ' and 'Sylvia' had significantly less leaf blackening with glucose treatments of 4 and 10%. Leaf blackening of 'Sheila', P. cynaroides and P. grandiceps was not significantly reduced by glucose pulsing. P. magnifica showed a small, but significant, reduction in leaf blackening in response to the 3, 6 and 9% treatments after 10 days only, but despite this, leaf blackening was unacceptably high. 'Pink Ice' harvested at the soft tip stage had less leaf blackening than those harvested open or closed. Toxicity symptoms on the leaves, and in some instances flowers, were observed at higher glucose concentrations (8 and 10%) onP. grandiceps, P. cynaroides, 'Cardinal' and 'Sheila'. All glucose treatments resulted in toxicity symptoms on P. magnifica. A decrease in nonstructural carbohydrates post-harvest apparently occurs in all proteas but it appears that only members of the Ligulatae respond to glucose. Glucose pulsing followed by cold storage at 1°C for three weeks in combination with post-storage glucose vase solutions, significantly reduced leaf blackening of some Protea cultivars. Glucose (1 and 2%), with hypochlorite, significantly delayed leaf blackening in 'Cardinal' and 'Sylvia' after seven days. Leaf blackening of 'Brenda', 'Carnival', 'Pink Ice' and 'Susara' was not significantly reduced by the glucose vase solutions. Other disinfectants, in combination with the sugar treatments, need to be evaluated since the hypochlorite treatment had a dehydrating effect on all the cultivars and resulted in increased leaf blackening. Carbohydrate supplementation of protea flowers with glucose, pre and post-storage, will help meet the post-harvest carbohydrate requirements of certain Protea cultivars and species to an extent. Glucose treatments must be seen in conjunction with maintaining the cold chain and when combined with cold chain maintenance, can extend the storage and vase life. / AFRIKAANSE OPSOMMING: Protea snyblomme word wêreldwyd uitgevoer alhoewel die vaasleeftyd van sommige spesies en kultivars beduidend verkort word deur na-oes loof verbruining. Navorsing het koolhidraatverbruik positief gekorreleer met hierdie probleem. Gevolglik is 'n studie gemaak van die koolhidraatstatus van verskeie spesies en kultivars asook die effek van addisionele glukose (voor en na opberging) op loofverbruining. Glukose, fruktose, sukrose en stysel konsentrasies van verskeie Protea spesies en kultivars wat in water gehou is, is bepaal met oes en weer met die eerste tekens van loofverbruining. Al die gemete koolhidraatkonsentrasies het beduidend afgeneem in 'Carnival', 'Pink Ice' en 'Sheila'. In 'Cardinal' het al die koolhidraatkonsentrasies beduidend afgeneem, behalwe vir die sukrosekonsentrasie in die blom. 'Susara' en 'Ivy' het baie hoë begin koolhidraatkonsentrasies in die blare wat beduidend afneem. Die baie hoë inisiële koolhidraatkonsentrasies in die blom van 'Ivy' neem beduidend af met tyd. 'Brenda' verskil van die ander kultivars en spesies deurdat die glukosekonsentrasies toeneem met tyd. Koolhidraatkonsentrasies van die meeste getoetste proteas neem beduidend af vanaf oes totdat die eerste tekens van loofverbruining verskyn. Dit het die afhanklikheid van die blare en blom op die koolhidraatreserwes beklemtoon en daardeur verder die koolhidraatteorie ondersteun. Die blomme is gekarakteriseer deur hoë fruktose- en glukosekonsentrasies en lae sukrosekonsentrasies wanneer dit met die blare vergelyk is.Die hipotese is gestel dat die voorsiening van glukose, vir 'n aantal ure, gekombineerd met koue opberging by 1°C vir drie weke loofverbruining beduidend sal verminder. 'Brenda', 'Cardinal', 'Carnival', 'Pink lee', 'Susara' en 'Sylvia' het beduidend minder loofverbruining met glukose behandelings tussen 4 en 10%. Loofverbruining van 'Sheila', P. cynaroides en P. grandiceps is nie beduidend verminder deur glukose behandelings nie. P. magnifica het 'n klein, maar beduidende verlaging in loofverbruining getoon met die 3, 6 en 9% behandelings na 10 dae, maar ten spyte hiervan was loofverbruining onaanvaarbaar hoog. 'Pink lee' is geoes by die sagte punt stadium en het minder loofverbruining gehad as blomme wat oop of toe geoes is. Toksisiteitsimptome op die blare, en in sommige gevalle blomme, is waargeneem met hoër glukose konsentrasies (8 en 10%) op P. grandiceps, P. cynaroides, 'Cardinal' en 'Sheila'. Alle glukosebehandelings het toksisiteitsimptome tot gevolg gehad op P. magnifica. 'n Afname in nie-strukturele koolhidrate na oes kom waarskynlik voor in alle proteas maar dit wil voorkom of slegs lede van die Ligulatae positief reageer op glukose. Glukosebehandeling gevolg deur koue opberging by 1°C vir drie weke in kombinasie met na-stoor glukose vaasoplossings het loofverbruining van sommige Protea kultivars beduidend verminder. Glukose (l en 2%), saam met hipoehloriet, het loofverbruining beduidend verminder in 'Cardinal' en 'Sylvia' na sewe dae. Loofverbruining van 'Brenda', 'Carnival', 'Pink lee' en 'Susara' is nie beduidend verminder deur die glukose vaasoplossings nie. Ander ontsmettingsmiddels in kombinasie met die suikerbehandelings moet geëvalueer word aangesien die hipoehlorietbehandeling 'n dehidrerende effek op al die kultivars gehad het en 'n toename in loofverbruining tot gevolg gehad het. Byvoeging van glukose by proteablomme, voor en na opberging, sal tot 'n mate help om in die na-oes koolhidraatbehoeftes van sekere Protea kultivars en spesies te voorsien. Glukosebehandelings moet saam met die beheer van die koueketting gesien word en wanneer gekombineerd met koueketting beheer kan dit opberg en vaasleeftyd verleng.

M.Sc. (Botany) / The purpose of this investigation was to determine the following: (i) The effect of water loss by transpiration on the browning of foliage of Protea neriifolia. (ii) Microscopic characteristics of leaves and stems of different P. neriifolia variants. (iii) A comparison of the vase and postharvest life of several P. neriifolia variants. (iv) The concentration of leuco-anthocyanins (brow= ning components) in individual leaves situated on different locations on peduncles of diffe= rent P. neriifolia variants. Protea repens was included in some investigations since this species is less subjected to browning of foliage.

Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2016. / This study focused on optimising four types of in-vitro conservation methods, namely: 1), micropropagation, 2) in-vitro slow growth, 3) seed germination and 4) cryopreservation for selected endangered plant species indigenous to the Cape Floristic Region. It is one of the targets set by United Nations millennium development goals, to integrate different conservation measures in order to preserve plant diversity and mitigate losses of genetic diversity. Therefore this study uses Phalaenopsis hybrids as a trial species that can be studied for the conservation of endangered Disa and Eulophia species through micropropagation and in vitro slow growth. Also conservation attempts on Leucadendron and Mimetes species that occur in the Cape Floristic Region were attemted to increase population densities by increasing germination percentages using smoke. Furthermore, the study attempted to store seeds by assessing different cooling rates for optimising cryopreservation measures for effective conservation. The use of tissue culture to increase propagules especially critically endangered species in South African has proven to be feasible. For the trial hybrids, shoot and protocorm explants of Phalaenopsis Psychosis Pink X P. No. 1; P. Large white X P. Large pink; P. No. 1 X P. Large pink; P. Mini pink X Brighton belle; and the P. aphrodite formed clusters of protocorms and shoots when cultured on ½ strength MS media supplemented with 10, 20 and 30gL-1 banana extract or ½ strength Murashige and Skoog, (1962) (MS) media supplemented with peptone. Continuous protocorms formation could therefore be obtained by culturing endangered Disa and Eulophia shoots and protocorms on banana containing media. Plantlet conversion from somatic embryos produced on 10gL-1 banana extract enriched media was successfully achieved on ½ strength MS supplemented with 20gL-1 sucrose and no plant growth regulators in the medium. However, optimum rooting was achieved on ½ strength MS supplemented with 30gL-1 of banana extract and this medium yielded the highest survival percentages for plantlet acclimatisation. Furthermore, ½ strength MS supplemented with 1gL-1 of peptone served as a stimulant for shoot development and protocorm formation. When coupled with banana extract at all stages of development, regeneration and rooting were enhanced.

The family Proteaceae is distributed predominantly in the south-western Cape Province of South Africa and south-western and south-eastern Australia, areas which fall within the climate term mediterranean ecosystems. A major characteristic of these areas is the low level of total nutrients in the soil, particularly nitrogen and phosphorus. In their natural habitat, therefore, Proteaceae occur on well-drained and highly leached soils of low nutrient status. Efficient nutrient cycling processes, combined with morphological adaptations designed to facilitate maximum absorption of available nutrients (for example, proteoid roots in the Proteaceae), conserve the limited nutrients available, allowing for the continued growth of these shrubs under conditions of low nutrient availability. In recent years, flowers of certain species of Proteaceae have become popular as cut-flowers. As a result, many species of Proteaceae are currently cultivated worldwide, under conditions that match as closely as possible those found in mediterranean ecosystems. Traditionally, the shrubs are cultivated on nutrient poor soils and of concern is the loss of nutrients through the removal of flowers for commercial sale. Therefore, the aim of the present study was to evaluate growth and mineral cycling in the proteaceaous shrub, Protea neriifolia R.Br., cultivated in a summer rainfall area in South Africa. Nutrient loss through flower removal and its effect on nutrient cycling was quantified. Optimum levels of ammonium nitrogen, phosphorus and potassium for the growth of P. neriifolia seedlings was determined and this formed the basis for the fertilization of mature P. neriijolia shrubs. The effects of inorganic fertilizers on growth and mineral cycling in mature P. neriijolia shrubs was monitored and the effectiveness of inorganic fertilizers, applied to redress nutrient loss, assessed. The primary response of seedlings of P. neriifolia to applied ammonium nitrogen, phosphorus and potassium was to ammonium nitrogen, with increased growth with increasing levels of applied ammonium nitrogen, to a maximum of 7 mM applied as 60 ml per week. Seedling response to applied phosphorus and potassium became noticeable only at higher levels of ammonium nitrogen supply, and at these levels seedlings were observed to respond favourably to relatively high phosphorus (0.65 mM) and potassium (1.25 mM) levels, also applied as 60 ml per week. Since nitrate nitrogen has been shown to be toxic to certain Proteaceae it was not tested in this investigation. However, results from the nursery trial suggested favourable P. neriijolia growth with a non-nitrate inorganic fertilizer with an NPK ratio of approximately 5: 1:3 (mass basis) and this was used as a basis for testing the effects of inorganic fertilizers on growth and nutrient cycling in mature P. neriijolia shrubs. Growth and nutrient cycling was monitored in mature P. neriijolia shrubs for four years: two years prior to the application of inorganic fertilizers and two years with the application of inorganic fertilizers, including unfertilized control shrubs. Two inorganic fertilizer preparations were tested. Both had as their base the commercial slow-release urea based fertilizer, Plantosan, which has an NPK ratio of 5: 1:3. This was supplemented with either ammonium sulphate or urea at a rate of 80 g per running metre every three months. Whole shrub dimensions showed similar growth of P. neriijolia shrubs cultivated in a summer rainfall area to the growth of the species in its natural habitat. Applied fertilizers did appear to increase growth, although these results became apparent only after 18 months. As recorded in other Proteaceae, the stem length of all shrubs decreased with increasing age of the shrubs although this decrease was less in shrubs receiving inorganic fertilizers. Branching did not appear to be affected by shrub age or the application of inorganic fertilizers. However, shrub reproductive productivity did increase with age, with greater increases in fertilized shrubs. Furthermore, flowers from fertilized shrubs were larger than those from unfertilized shrubs, although this phenomenon also only became apparent after 18 months. There was also a change in nutrient allocation patterns with those shrubs growing on soils of lowest nutrient availability directing more resources to root growth. This appeared to occur at the expense of stem material which, in each case, accounted for more than 50% of the total shrub biomass.Although shrub age and the application of fertilizers did influence total shrub growth, the timing of growth events were not affected. They were, however, not synchronous to growth events in P. neriijolia growing in its natural habitat. Vegetative growth showed a peak in early spring (September) and the peak reproductive period was in autumn (March, April and May). Maximum litter production (comprising more than 90% leaf litter) occurred in late autumn to early summer (May to December) and this, too, was not affected by shrub age or the application of inorganic fertilizers. Proteoid root occurrence was greatest in late winter/spring (August to November), co-incident with peak above-ground vegetative growth. There are two models that have been developed to describe the growth of overstorey shrubs in mediterranean ecosystems. In the first, the availability of nutrients is described as being of over-riding importance in determining growth events, while in the second model, soil moisture and temperature are regarded as primary growth detenninants. Neither model could adequately explain the shift in phenophase observed in P. neriifolia cultivated in a summer rainfall area. However, soil moisture and temperature do appear more important in determining phenophase events, particularly since the application of inorganic fertilizers did not appear to alter the timing of these growth events. Nevertheless, the importance of nutrients cannot be ignored as growth can occur only provided sufficient nutrients are available. Seasonal variations in nutrient concentrations of leaf, stem, floret and bract material were observed both prior to and after the application of inorganic fertilizers. However, of importance is that only shrubs receiving Plantosan plus ammonium sulphate retained comparable nutrient levels in tissue types compared with nutrient levels in the corresponding tissue types prior to the application of inorganic fertilizers. Shrubs receiving Plantosan plus urea and unfertilized shrubs had lower nutrient levels suggesting growth at the expense of previously absorbed nutrients. This was supported by a change in nutrient allocation patterns, particularly more nutrients in below-ground biomass in shrubs of the latter two treatments. The cycling of nitrogen, phosphorus and potassium was measured prior to and after the application of inorganic fertilizers. During nutrient cycling, the amount of nitrogen circulated was larger than the amount of potassium which, in turn, was larger than the amount of phosphorus. Three nutrient pools, in the above- and below-ground biomass and the soil, were measured and these comprise the plant/soil system. Inputs into the plant/soil system measured were from rainfall and inorganic fertilizers. Nutrient flows within the plant/soil system measured were leaching, due to rainfall, from the shrub onto the soil, litter production and decomposition, and nutrient uptake by the shrubs, into above- and below-ground nutrient pools. Losses from the plant/soil system recorded in this study were losses from the soil through stream-water, and the largest loss, loss through the removal of flowers for commercial sale. In the absence of flower harvesting the flow of nutrients in the plant/soil system, combined with inputs from rainfall, appeared adequate for the continued growth of the shrubs. However, in the presence of flower harvesting there appeared to be a nutrient budget deficit. This deficit appeared to worsen with increasing shrub age and increasing reproductive productivity in the absence of inorganic fertilizer applications. This was confirmed by nutrient depletion from the soil available nutrient pool. Although inorganic fertilizers did not dramatically alter soil total nutrient pools, soil levels of soluble nitrogen and available phosphorus did show slight increases but not in accordance with the levels of fertilizers applied. It is likely that a high proportion of the applied fertilizers was lost to the plant/soil system before becoming available to the system. This could have occurred through leaching through the soil profile although this was not measured in this study. Nevertheless, inorganic fertilizers did appear to compensate for nutrient loss through the removal of flowers for commercial sale, and the ammonium sulphate supplemented preparation resulted in the most favourable response. Due to a number of cultivation practices which affected the growth of the P. neriifolia shrubs, results are not always strictly comparable with natural systems. However, a number of results obtained in this invegstigation do have horticultural implications and these are briefly discussed with regard to the cultivation of the Proteaceae, particularly P. neriifolia cultivation. / Thesis (Ph.D.)-University of Natal, Durban, 1991.

This study was conducted to determine if, and how, over storey proteoid shrubs affect the species richness of a southern Cape mountain fynbos community. Protea eximia, P. lorifolia and P. repens were the dominant overstorey shrubs in the community studied. The percentage canopy cover and density of overstorey protea shrubs before a fire were regressed against the a-diversity of understorey species after a fire, for spatial scales ranging from 1 - 100m². High canopy cover percentages (≥ 50%) and high densities (≥ 30 plants per 100m²) of overstorey proteas before a fire enriched the a-diversity levels of understorey species after a fire. The spatial scale at which α-diversity was measured affected results. The number of understorey species at a site, where overstorey proteas were absent for several fire-cycles, was compared with those where overstorey proteas persisted. The number of understorey species was least where the overstorey proteas were lacking for several fire-cycles, but results also depended on the spatial scale at which α-diversity was measured. The basal cover percentage and density of sprouting understorey species of two sites, burned at several short (6 year) fire-cycles and where overstorey proteas were lacking, were compared with those of an adjacent site which was not burned for 28 years and where the overstorey proteas persisted. Where several short fire-cycles eliminated the overstorey proteas, the basal cover percentage of understorey sprouters was approximately 32% higher than where the overstorey shrubs persisted. The number of understorey species in dense clumps of understorey sprouters was contrasted against those on 0.25m² quadrats located in the open and under burned skeletons of overstorey protease In dense clumps of sprouters the mean number of understorey species was less than half of that for quadrats located in the open, or for quadrats located under the burned protea skeletons. Species specific competitive interactions amongst overstorey protea and understorey sprouter species were examined for several pyric successional stages. Competitive interactions between overstorey proteas and understorey sprouters were evident in all pyric successional stages. Results indicate that the overstorey proteoid shrubs are important to restrain the competitive ability of understorey sprouters, to prevent homogeneity in post-fire regeneration niches and to amplify within-community patchiness of understorey species, which ultimately enhances the species richness of fynbos communities. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1996.

Dissertation (PhD)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

Ph.D. / Please refer to full text to view abstract