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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.
221

An investigation of the antiviral effect of several Arizona plant extracts on influenza virus A in mice

Fried, Mary Lakritz, 1925- January 1954 (has links)
No description available.
222

Anticancer Structure-Activity Relationships of Semi-Synthetic Analogs of Nordihydroguaiaretic Acid

Meyers, Ross Owen January 2005 (has links)
Nordihydroguaiaretic Acid (NDGA) is a polyphenol, antioxidant, natural product lignan isolated from the creosote bush (Larrea tridentata). The in vivo and in vitro Pharmacology and Toxicology of NDGA has been continuously studied for more than 36 years. The Pharmacology of NDGA has been studied in Diabetes, Alzheimer's disease and Amyotrophic Sclerosis. Most of the research on NDGA has been in anticancer and cancer prevention models. Toxicology studies reveal NDGA-mediated hepatotoxicity and nephrotoxicity. This data has influenced a recent interest in semi-synthetic derivatives of NDGA focused on modifying the phenolic groups which are responsible for in vivo toxicity. The tetra-methylether of NDGA (M4N) has shown reduction in toxicity and enhanced anti-melanoma activity when compared to NDGA.The specific aim of this project was to increase the number of NDGA analogs with anti-melanoma activity and explore a novel synthetic approach by binding the ortho-phenols together by one atom, creating a 5-membered ring as opposed to the prior work which involved tetra-substituted phenolic hydroxyl group modifications.Eleven new analogs were synthesized, characterized and evaluated for their anti-melanoma activity. The anti-melanoma activity was evaluated by 5-day colorimetric-based, and DNA, RNA and protein synthesis inhibition-based cytotoxicity assays. The cytotoxicity assays were compared to NDGA and M4N in terms of structure and activity. Selected analogs were evaluated in an in vivo, mouse, tumor growth inhibition model. In the first in vivo model, tetra acetyl NDGA (TA-NDGA) and ortho-cyclic carbonate NDGA (OCC-NDGA) were evaluated at two dose-levels, 100 mg/kg and 200 mg/kg. They both showed dose-dependent, but moderate tumor growth inhibition at the 200 mg/kg dose-level. An ortho-cyclic sulfate of NDGA showed in vivo toxicity at 100 mg/kg. In the second in vivo model, the dose was escalated to 300 mg/kg, TA-NDGA showed moderate tumor growth inhibition, but OCC-NDGA-mediated tumor growth inhibition was not repeated. However, in the second study an ortho-difluoromethylene NDGA analog did show moderate tumor growth inhibition.Structure-activity relationships indicated that the ortho-cyclic analogs are inferior to the tetra-substituted phenolic group-modified analogs in terms of anti-melanoma activity and therefore future synthesis' should be focused on generating more tetra-substituted phenolic group analogs of NDGA.
223

Propagation of Camptotheca acuminata

Maxwell, Douglas Wayne 30 September 2004 (has links)
Research was undertaken to optimize propagation of the southern China native Camptotheca acuminata Decaisne, source of the medicinal compound camptothecin that is used in the treatment of multiple forms of cancer and other diseases. The study focused on cutting propagation, micropropagation, and seed storage. Softwood cuttings of C. acuminata rooted readily in intermittent mist (4 sec on every 6 min.) in coarse vermiculite when treated with K-IBA (indolebutyric acid, potassium salt) quick dips ranging from 4.14 mM to 37.3 mM, with a 29.0 mM quick dip (5 sec.) promoting 82% rooting with little foliar damage. Actively growing shoot tip explants were tissue cultured on media containing Murashige and Skoog, Gamborg's B5, and Woody Plant Medium (WPM) salts in factorial combinations with BA (benzyladenine). WPM containing 4.44 μM BA promoted excellent shoot proliferation; microcuttings were rooted, acclimated, and grown in the greenhouse. Seeds stored in polyethylene bags in a refrigerator (4°C) or freezer (-20°C) maintained good germination (81% and 80%, respectively) while seeds stored at room temperature (25°C) in polyethylene bags lost germination ability quickly (58%) after one year of storage. C. acuminata is readily adaptable to modern nursery techniques for either vegetative or seed propagation.
224

Vaistinių dekoratyvinių augalų populiarumas ir gyventojų požiūris į juos / Popularity of medicinal ornamental plants and residents’ attitude towards them

Jankauskaitė, Indrė 03 September 2010 (has links)
Darbo tikslas – surinkti ir aptarti duomenis apie vaistinius dekoratyvinius augalus, nustatyti ir pateikti jų auginimo dėsningumus Kirnaičių kaime. Darbo uždaviniai: 1. Išsiaiškinti kokius vaistinius augalus žmonės naudoja gydydamiesi. 2. Išsiaiškinti kaip žmonės vertina vaistinių augalų dekoratyvumą. 3. Įvertinti kokie vaistiniai augalai auginami, kaip ir kur jie išsodinti. 4. Pateikti rekomenduojamų auginti augalų sąrašą. Darbo objektu pasirinkta 50 Kirnaičių kaimo sodybų ir juose esantys gėlynai. Tyrimas buvo atliktas naudojant apklausos anketas ir dvi gėlynų tyrimo lenteles. Buvo išdalinta 100 apklausos anketų, siekiant išsiaiškinti žmonių nuomonę apie vaistinių augalų dekoratyvias savybes. Kol sodybų gyventojai pildydavo anketas, taip pat buvo pildomos dvi lentelės apžiūrint gėlynus. Viena lentele buvo siekiama išsiaiškinti kaip dažnai vieni ar kiti vaistiniai augalai yra auginami, o kita kokiu išsodinimo būdu jie dažniausiai yra auginami. Analizuojant apklausos anketos gautus rezultatus, nustatyta, kad didžioji dalis Kirnaičių kaimo gyventojų domisi vaistiniais augalais. Vaistiniai augalai jų gėlynuose sudaro trečdalį visų auginamų gėlių, iš to galima spręsti, kad yra vertinamas jų dekoratyvumas. Iš anketos gautų duomenų taip pat nustatyta, kad kuo daugiau naudojami vaistiniai augalai, tuo didesnę dalį jie sudaro gėlyne auginamų augalų. Išanalizavus pildytas lenteles nustatyti dažniausiai auginami vaistiniai augalai: Hepatica nobelis Mill., Viola tricolor L., Ruta... [toliau žr. visą tekstą] / The objective of the paper is to collect and discuss data about medicinal decorative plants, to establish and present the regularities of growing thereof in Kirnaičiai Village. The tasks of the study: 1. To ascertain, which medicinal plants are used by people for treatment. 2. To ascertain, how people evaluate the decorativeness of medicinal plants. 3. To assess, which medicinal plants are grown, how and where are they planted. 4. To present the list of plants recommended to grow. 50 homesteads of Kirnaičiai Village and the parterres thereof were selected as the object of the research. The research was performed using questionnaire surveys and two tables of research of the parterres. 100 questionnaire surveys were distributed in order to ascertain the peoples’ opinion about decorative qualities of medicinal plants. While the residents of the homesteads were filling the surveys, the two tables were filled too reviewing the parterres. One table was designated to ascertain how often these or that medicinal plants were grown, ant the other one – to ascertain the most usual method of growing thereof. Analysing the received results of the questionnaire survey, it was established that the most part of the residents of Kirnaičiai Village were interested in medicinal plants. The medicinal plants make one third of grown flowers in their parterres, it allows to conclude that the decorativeness thereof is appreciated. It was also established from the data received in the survey... [to full text]
225

In vitro studies and phytocompound analysis in Lessertia frutescens (Fabaceae)

Shaik, Shakira. January 2011 (has links)
The cancer bush (Lessertia frutescens L.) is an important leguminous perennial native to southern Africa and has been used for centuries in traditional medicine by the continent’s diverse cultural groups. Like many other legumes, the seeds of this species exhibit dormancy. Moreover, woody plants are typically difficult to propagate in in vitro culture systems. But in vitro shoot cultures are valuable in providing an alternative means of deriving desired secondary metabolites or phytocompounds, under controlled conditions. This study describes novel protocols for breaking seed dormancy, rapid and efficient in vitro propagation, bioreactor culture, and comprehensive phytochemical data following screening and analysis of in vitro and field extracts of L. frutescens. Experiments using physical, mechanical and chemical pre-sowing treatments were conducted to determine the germination response of this species. The results indicated that seeds of L. frutescens exhibited exogenous dormancy due to the inhibitory effect of the hard coat on germination. Seed dormancy was released by mechanical scarification in which 100 % germination was achieved. In vitro propagation studies using single node explants in Murashige and Skoog (MS) medium supplemented with combinations of different concentrations of benzyladenine and naphthaleneacetic acid revealed a maximum number of 10 shoots per explant in solid medium, and 12.9 shoots per explant in liquid medium inside a temporary immersion bioreactor. Indirect shoot organogenesis and plant regeneration using rachis and stem segments was achieved with the highest percentage of explants forming shoots (88.8 %) from rachis explants cultured onto MS medium supplemented with thidiazuron. Direct shoot organogenesis from hypocotyl and cotyledon segments was also achieved in L. frutescens. The highest shoot regeneration using hypocotyls (83 %) was obtained in MS medium supplemented with kinetin whilst the highest shoot regeneration using cotyledons (46 %) was obtained in MS medium supplemented with kinetin in combination with benzyladenine. Successful rooting (up to 80 %) and acclimatization (up to 90 % survival rate) was attained. Spectrophotometric and gravimetric methods indicated that saponins were the most abundant, followed by phenolics, flavonoids and then alkaloids in in vitro leaf extracts then in field leaf extracts and seed extracts, respectively. After qualitative analysis these extracts were also found to contain tannins, phlobatannins and cardiac glycosides of medicinal interest. By using gas and liquid chromatography the presence of the medicinally important L-canavanine, gamma amino-butyric acid and D-pinitol was verified in in vitro leaf, field leaf and seed extracts. In vitro leaves had higher quantities of all compounds, except for D-pinitol. Phytocompound analysis of shoots derived from several of the cytokinin-enhanced media showed that these organs contained higher quantities of L-canavanine compared to the control. This study, therefore, highlights the potential techno-economic production of medicinal phytocompounds from in vitro leaves of L. frutescens following large scale production using the protocols described in this study. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2011.
226

Synthesis and analysis of Eriosema isoflavonoids and derivatives thereof.

Selepe, Mamoalosi Alix-Maria. January 2011 (has links)
Kraussianone 1 and kraussianone 2 were previously isolated as active compounds from the roots of Eriosema kraussianum Meisn., a plant used for the treatment of male impotence and urinary complaints in KwaZulu-Natal. The objectives of this study were firstly, to develop a method for the analysis of metabolites from E. kraussianum and other Eriosema plants that are used for erectile dysfunction and secondly, to develop synthetic methods for kraussianone 1 and structurally related compounds. A reversed-phase HPLC-PDA method was developed for the analysis of the extracts of plants from different sources, two of which were authentic E. kraussianum collected from the Drakensberg and Pietermaritzburg. The roots of other Eriosema species called ubangalala and uqonsi in Isizulu were also analysed. These plants were bought from the local herbal traders. The extracts of the two E. kraussianum plants and one uqonsi sample showed a similar chemical profile, even though there were variations in the relative concentrations of the metabolites within each plant. In these three plants, kraussianone 1, the most active metabolite of E. kraussianum, occurred in relatively low quantities, whereas kraussianone 2 was one of the major constituents. The other commercial plants that were analysed contained different compounds from those found in E. kraussianum. The HPLC method developed herein facilitates rapid identification and relative quantification of metabolites from E. kraussianum. Strategies based on semi-synthesis and total synthesis were employed for the preparation of kraussianone 1. The semi-synthetic route was based on the transformation of the prenyl side chain of kraussianone 2 into a linear dimethylpyran scaffold fused to the A-ring. Two routes were investigated for the semi-synthesis of kraussianone 1 from kraussianone 2. In the first route, the dimethylchromene ring was to be prepared by the acid-catalysed cyclisation of the prenyl group of kraussianone 2, followed by dehydrogenation of the resulting dimethylchroman chromophore. This route was abandoned due to poor regioselectivity of the cyclisation reaction and the difficulty of oxidising the dimethylchroman scaffold on the phloroglucinol moiety into a dimethylchromene. The second strategy involved selective protection of the OH-2', followed by DDQ-mediated oxidative cyclisation of the prenyl group to OH-7. This was the most viable route and kraussianone 1 was prepared in an overall yield of 54% from kraussianone 2. The total synthesis of kraussianone 1, on the other hand, employed the Suzuki-Miyaura reaction for the construction of the isoflavone nucleus and the regioselective introduction of the dimethylpyran scaffolds to the A- and B-rings. The key precursors in this synthesis were 3-iodo-5,7-dimethoxymethoxychromone and a boronic acid coupling partner, 7- benzyloxy-2,2-dimethylchromene-6-boronic acid, already bearing the prerequisite chromene scaffold attached to the B-ring. The isoflavones genistein, 2-hydroxygenistein, eriosemaone D and a geranyl analogue of kraussianone 1 were prepared via the route developed for the total synthesis of kraussianone 1 by structural modifications of rings A and B. Furthermore, this synthetic approach was expanded to the synthesis of the coumarochromones lupinalbin A and lupinalbin H. The development of the feasible semi-synthetic and total synthetic routes described herein for kraussianone 1 is of importance for the production of material for an in depth study of the pharmacological activities and the structure-activity relationship studies of kraussianone 1 and related compounds. / Thesis (Ph.D.)-University of KwaZulu-Natal, 2011.
227

Structure and synthesis of Gunnera perpensa secondary metabolites.

Peter, Xolani Kevin. January 2007 (has links)
The project focused on the isolation, characterization and synthesis of secondary metabolites of Gunnera perpensa L. (Gunneraceae), a South African medicinal plant used by many South African women to induce or augment labour and as an antenatal medication to tone the uterus. From the methanol extracts of the rhizomes we have isolated the compounds Z-venusol, methyl lespedezate, 4-6>-/?-D-glucopyranosyl-3,3',4'-tri-0- methylellagic acid and punicallagin. Structural elucidation of the compounds was performed using NMR spectroscopy. The presence of ellagic acid derivatives and hydrolysable tannins have not previously been reported from the family Gunneraceae. The study also focuses on the development of an HPLC analytical method to fingerprint the crude extracts of G perpensa. This method was used to determine the chemical composition of the rhizomes of the G. perpensa collected in different parts of South Africa. It is clear from the HPLC study that the rhizomes contain large concentrations of the hydrolysable tannin punicalagin and the second most abundant metabolite was Z-venusol. However, it was observed from plants collected in different regions that the ratio between punicalagin and Z-venusol differs substantially in the different extracts. An ellagic acid derivative isolated from G. perpensa contains a biaryl structure derived from gallic acid. The synthesis described in this thesis focused on reaction methods to access unsymmetrical biaryls and two synthetic routes were investigated - one that relies on the Ullmann reaction and the second that uses the Heck coupling reaction. Success of this coupling reaction towards the formation of ellagic acid derivatives was accomplished by the Heck coupling reaction method. One of the most important considerations towards the synthesis was the manipulation of hydroxyl groups of gallic acid by selective protection reactions that provide entry to the aforementioned preparation of unsymmetrical ellagic acid derivatives. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
228

The micromorphological and essential oil status of the foliar secretory structures of Ocimum obovatum E. Mey. ex Benth. subsp. obovatum (Lamiaceae)

Kasim, Nazeera. January 2011 (has links)
Ocimum obovatum E. Mey ex Benth. var. obovatum is a traditionally used medicinal plant that grows along the KwaZulu-Natal coast and the western Cape of South Africa. The plant is noted for its hair restoration properties, remedy for infantile abdominal pain and cramps and its use as an enema to treat epigastric conditions in children. The aims of this study were to document the micromorphology and ultrastructure of the foliar secretory structures responsible for the production and secretion of the essential oils and chemical composition of the secretion, which gives the plant a distinct aroma. It is believed that these oils contain the active ingredients that contribute to the medicinal properties of the plant. A variety of microscopic methods and histochemical and phytochemical tests were used to achieve this. Leaves in all stages of development were pubescent and gland dots, characteristic of plants in the genus, were found on both adaxial and abaxial surfaces. Three types of trichomes were found on both leaf surfaces across all stages of development; non-glandular trichomes and two types of glandular trichomes. Non-glandular trichomes are single, multicellular and uniseriate with microornamentation and a supportive cellular pedestal. The glandular trichomes consisted of peltate and capitate trichomes. Peltate trichomes are made up of four head cells and a very small basal cell that gives the glands the appearance of being sessile. The capitate trichomes were further divided into two types based on the morphology of the glands. Type I capitate trichomes are smaller than the larger peltate trichomes and are composed of one basal cell and a head consisting of two broad head cells. Type II capitate trichomes consisted of one basal cell, one stalk cell and a single oval head cell. Histochemical tests showed that peltate and Type I capitate trichomes have cutinized or suberized walls in the stalk cell to prevent the apoplastic flow of secretory material into neighbouring mesophyll tissue. The histochemical stains also showed that the secretory material present in the glandular trichomes are lipid in nature and essential oils are present. Ultrastructural studies showed polymorphic leucoplasts, few Golgi bodies, numerous vesicles and mini vacuoles, mitochondria and short profiles of endoplasmic reticulum cisternae. Phytochemical tests revealed the presence of essential oils that are terpene-rich. Flavonoids, tannins, saponins, terpenoids, fixed oils and fat, phenolics and cardiac glycosides were also detected in a crude ethanolic extract of the leaves. These chemical compounds appear to be responsible for the medicinal properties for which the plant is traditionally exploited. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2011.
229

Storage of frequently used traditional South African medicinal plants.

Stafford, Gary Ivan. January 2003 (has links)
The post-harvest physiology of nine frequently used indigenous southern African medicinal plants was investigated, in particular the effects of storage time and accelerated ageing on the biological activity and chemical constituents of these plants. Water, ethanol and hexane extracts of fresh plant material as well as material that had been stored in dry form in paper bags at room temperature for 90 days (short-term) were tested. Three bioassays, the COX-1 anti-inflammatory assay, nematode anthelmintic assay and minimum inhibitory concentration anti-bacterial assay, were used to determine biological activity. Thin layer chromatography of all the plant extracts were used to determine changes in chemical composition. The plants tested were Alepidea amatymbica Eckl. & Zeyh., Leonotis leonurus (L.) R. Br., Drimia robusta Bak., Vernonia colorata (Willd.) Drake, Scilla natalensis Planch., Eucomis autumnalis (Mill.) Chitt. subsp. autumnalis, Bowiea volubilis Harv. ex Hook. f., Helichrysum cymosum (L.) D. Don and Siphonochilus aethiopicus (Schweinf.) B. L. Burtt. Only those plants, which are known to exhibit a particular biological activity either traditionally or scientifically, were tested in the relevant bioassays. Of the plant extracts tested for anthelmintic activity only the water extracts showed activity and very little change in activity was observed after storage. Of the plant extracts tested for anti-inflammatory activity the ethanol extracts generally yielded highest activity. S. natalensis and B. volubilis both showed an increase in cyclooxygenase inhibition (anti-inflammatory) activity after storage whereas S. aethiopicus, H. cymosum, D. robusta and V. colorata showed a loss in activity after storage. The anti-inflammatory activity of E. autumnalis did not change. The water extracts of plants tested for antibacterial activity showed no activity, whereas the ethanol extracts generally showed an increase in activity. The TLC fingerprints indicated that there was chemical break-down during storage in certain species. These corresponded to the changes in biological activity. Alepidea amatymbica, Eucomis autumnalis, Helichrysum cymosum, Leonotis leonurus, Siphonochilus aethiopicus and Vernonia colorata were investigated further as to the effect of one year's storage (long-term storage) on their chemical composition and biological activity. Similar trends to that of the 90-day storage were observed. Activity gained in plants that were stored for 90 days was retained after a year of storage. Elevated temperature and humidity (55 C and 100% relative humidity) were used to accelerate the ageing process of Alepidea amatymbica, Leonotis leonurus and Vernonia colorata plant material. Again changes in the chemical composition and biological activity were observed, and the extent of these changes was greater than those in the stored material. The compounds responsible for the cyclooxygenase inhibition in the ethanolic extracts of Alepidea amatymbica leaf material appear to be stable and were not affected by the conditions of the accelerated ageing procedure (55 C and 100% humidity for seven days), but the root material lost activity, as did the leaf material of Leonotis leonurus. The leaf material of Vernonia colorata showed a slight (8%) increase in cyclooxygenase inhibition activity. The response of the plant material to accelerated ageing with respect to antibacterial activity varied with plant species. Alepidea amatymbica root material and Vernonia colorata leaf material appear to be stable whereas the other plant materials lost activity after prolonged (25 days) ageing. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
230

Response of the endangered medicinal plant : Siphonochilus aethiopicus (Schweif) B.L. Burt. to agronomic practices.

Hartzell, James Francis. January 2011 (has links)
This study examines field cropping constraints for domestication of an endangered, wild medicinal plant, Siphonochilus aethiopicus, (Schweif.) B.L. Burt. Extensive literature review and careful observations of plant growth behavior during two years of crop trials overturned several long-held but erroneous claims that have consistently appeared in the scholarly literature, and revealed previously undocumented plant growth characteristics. S. aethiopicus (Schweif.) B.L. Burt. is a rhizomatous corm, not a rhizome. Field growth observations demonstrated clearly that the false stem and leaves grow continuously from emergence in September to senescence in April-May; the corm retains its tuberous roots during winter senescence, and is genetically preprogrammed to shoot in September. Flowers may emerge throughout the growing season (not only initially prior to shoot emergence), typical leaf count is 11-15, not 6-8 as previously reported, numbers that remain constant even when the plant height increases by 20-30% under shade, and leaf distichy is independent of the sun’s course and is unaffected by mother corm orientation. S. aethiopicus proved to be unusually resistant to common field diseases and pests, and resilient to severe hail. The responses of S. aethiopicus were tested in a series of field trials to the effects of levels of compost, field spacing, size of planting material, addition of biocontrol agents, different degrees of shading, and factorials of the macronutrients Nitrogen, Phosphorous and Potassium. Spacing-Composted chicken litter combinations were tested in 2005-2006 in factorial combination with Spacing at 15 cm-4.5 kg ha-1, 20 cm-7.5 kg ha-1, 30 cm-10 kg ha-1, and 40 cm-15.5 kg ha-1, and these treatments were randomized with 4 Corm planting sizes (height by base diameter in mm): Small (S, 12.38 mm x 12.6 mm), Medium Small (MS, 29.65 mm x 27.93 mm), Medium Large (ML, 38.48 mm x 37.78 mm) and Large (L, 52.37 mm x 44.10 mm). 2005-2006 ANOVA tests showed significant differences between Spacing-Compost and Corm Size for the total harvest biomass measure, with 30 cm and 40 cm spaces better than 15 cm spacing, and Corm Size MS, ML and L all better than S, and ML better than MS. Total Corms harvested per block and ii Survival Percentage were similarly significant for Corm Size, but not Spacing. Corms smaller than the Small criteria were raised separately, under optimal conditions in a nursery. In a separate 2005-2006 Compost-only trial ANOVA tests did not find significant differences between compost levels. In 2006-2007 we tested Spacing separately at 5, 10, 15, 20, 30 and 40 cm between planted corms in each plot. We tested Compost levels separately, with 0, 5, 10 and 15 kg ha-1 compost per plot. In 2006-2007 only the ML and L sizes were used in an even mix. There were no significant differences between treatments due to high experimental error, but measurement across all production parameters showed a clear trend towards best performance at spacing between 20 and 40 cm. Overall the results from the Spacing, Compost-level and Corm Size trials suggest that 30 cm is perhaps the optimal field spacing, higher compost levels tend to give better results, and the ML and L corm sizes perform better in open-sun field trials. These parameters are recommended for further field studies and production. The effects of two commercial strains of Trichoderma spp were tested at recommended doses applied to S. aethiopicus. T. harzianum Strain B77 was used as a drench at planting in comparison with a Control and a fungicide in 2005-2006. There were no significant differences between treatments for Harvested Biomass or Survival Percentage. B77 did perform significantly better than the Fungicide in the Total Corm measurement, but neither treatment was significantly different from the Control. In sum, there was a weak trend towards a greater number of output corms as a result of the application of the biocontrol agent. In both 2005-2006 and 2006-2007 we tested T. harzianum Strain kd applied as a drench at planting, with a second drench at 4 weeks. In 2006-2007 there were no significant differences between treatments, but the trend was towards better performance as a result of the drench at planting only. In 2005-2006 open field trials had shown that S. aethiopicus is susceptible to sunburn and Erwinia soft rot when grown in the full sun. Therefore, we tested the effect of various shadecloth densities and colours on production performance in 2006-2007. Treatments were Control (full sun), 40% White (TiO2) (23% shade), 40% Grey (28-30% shade), Light Black (40%), Medium Black (50%), Dark Black (80%), and Red (40%). There were no significant differences between treatments, but the trends indicated that the Control (full sun) and Dark Black (80% shade) performed the worst. Colour of shade did not appear to be important, and plants under all the shadecloths with 40-50% shade grew best. In a factorial trial different levels of Nitrogen, Phosphorous, and Potassium (NPK)were tested, over two seasons. Four levels of each input were used: N at 0 (Control), 40 kg ha-1 (N1), 80 kg ha-1 (N1), and 120 kg ha-1 (N3). P levels were 0 (Control) 60 kg ha-1 (P1) ,120 kg ha-1 (P2) and 200 kg ha-1 (P3). K levels were 0 (Control), 100 kg ha-1 (K1), 200 kg ha-1 (K2), and 400 kg ha-1 (K3). In 2005-2006 there were no significant differences between treatments. In 2006-2007 data there were significant results for Nitrogen only within each repetition. However, significance disappeared when combining across repetitions. We then ran a Bootstrap re-sampling analysis of both 2005-2006 and 2006-2007 data (data were analyzed separately because of different plot sizes and corm numbers in the two years), looking at the optimal level of each macronutrient tested against all combinations of the other two. Though significant results were obtained for each individual level of each macronutrient against the others in combination, the difference between the confidence intervals was not significant. However, there was a clear trend: the optimum N levels were between 40 and 80 kg ha-1; optimum P level was 0 (the Control) and optimum K levels were between 100 and 200 kg ha-1. Tests of handling during harvest, storage, and planting yielded additional useful information for small scale commercial farmers. The optimal harvest time is May, when the false stem and leaves are senescing and yellow, but still upright and visible. Harvest is facilitated by moistening the soil to minimize breaking off of tuberous roots, with simple field washing to remove compacted soil highly recommended. Harvested corms and tuberous roots should be stored under air-restricted, cool conditions because the tuberous roots contain high moisture and will shrivel quickly when left exposed to air, and excessively dried corms will eventually die. Senesced mother corms should be discarded at harvest. Corms are genetically preprogrammed to shoot, so should be planted in September in soft soil, with 1-2 cm of soil coverage. The studies provide a framework for developing the basic agronomy for the domestication and commercial crop production of an endangered medicinal plant species. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

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