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Drought tolerance and water-use of selected South African landraces of Taro (Colocasia esculenta L. schott) and Bambara groundnut (Vigna subterranea L. Verdc)Mabhaudhi, Tafadzwanashe. 18 November 2013 (has links)
Issues surrounding water scarcity will become topical in future as global fresh water resources
become more limited thus threaten crop production. Predicted climate change and increasing
population growth will place more pressure on agriculture to produce more food using less
water. As such, efforts have now shifted to identifying previously neglected underutilised
species (NUS) as possible crops that could be used to bridge the food gap in future. Taro
(Colocasia esculenta L. Schott) and bambara groundnut (Vigna subterranea L. Verdc)
currently occupy low levels of utilisation in South Africa. Both crops are cultivated using
landraces with no improved varieties available. Information describing their agronomy and
water–use is limited and remains a bottleneck to their promotion. The aim of this study was to
determine the drought tolerance and water–use of selected landraces of taro and bambara
groundnut from KwaZulu-Natal, South Africa.
In order to meet the specific objectives for taro and bambara groundnut management, an
approach involving conventional and modelling techniques was used.
Three taro landraces [Dumbe Lomfula (DL), KwaNgwanase (KW) and Umbumbulu
(UM)] were collected from the North Coast and midlands of KwaZulu-Natal, South Africa, in
2010. The UM landrace was classified as Eddoe type taro (C. esculenta var. antiquorum)
characterised by a central corm and edible side cormels. The DL and KW landraces were
classified as Dasheen (C. esculenta var. esculenta), characterised by a large edible main corm
and smaller side cormels. A bambara groundnut landrace was collected from Jozini, KwaZulu-
Natal, and characterised into three selections (‘Red’, ‘Light-brown’ and ‘Brown’) based on
seed coat colour. Seed colour was hypothesised to have an effect on seed quality. Field and
rainshelter experiments were conducted for both taro and bambara landraces at Roodeplaat in
Pretoria and Ukulinga Research Farm in Pietermaritzburg, over two growing seasons (2010/11
and 2011/12).
The objective of the field trials for taro and bambara groundnut was to determine
mechanisms associated with drought tolerance in taro and bambara groundnut landraces.
Experiments were laid out in a split-plot design where irrigation [fully irrigated (FI) and
rainfed (RF)] was the main factor and landraces (3 landraces of either taro or bambara
groundnut) were sub-factors. Treatments were arranged in a randomised complete block
design (RCBD), replicated three times. Rainfed trials were established with irrigation to allow
for maximum crop stand. Thereafter, irrigation was withdrawn. Whilst experimental designs
and layouts for taro and bambara groundnut were similar, differences existed with regards to
plot sizes and plant spacing. Trials were planted on a total land area of 500 m2 and 144 m2, for
taro and bambara groundnut, respectively. Plant spacing was 1 m x 1 m for taro and 0.3 m x
0.3 m for bambara groundnut. Irrigation scheduling in the FI treatment was based on ETo and
Kc and was applied using sprinkler irrigation system.
Separate rainshelter experiments were conducted for taro and bambara groundnut
landraces at Roodeplaat, to evaluate growth, yield and water-use of taro and bambara
groundnut landraces under a range of water regimes. The experimental design was similar for
both crops, a RCBD with two treatment factors: irrigation level [30, 60 and 100% crop water
requirement (ETa)] and landrace (3 landraces), replicated three times. Irrigation water was
applied using drip irrigation system based on ETo and Kc.
Data collection in field and rainshelter trials included time to emergence, plant height, leaf
number, leaf area index (LAI), stomatal conductance and chlorophyll content index (CCI). For
taro field trials, vegetative growth index (VGI) was also determined. Yield and yield
components (harvest index, biomass, corm number and mass) as well as water–use efficiency
(WUE) were determined at harvest.
Intercropping of taro and bambara groundnut was evaluated under dryland conditions
using farmers’ fields at Umbumbulu, KwaZulu–Natal, South Africa. The experimental design
was a RCBD replicated three times. Intercrop combinations included taro and bambara
groundnut sole crops, a 1:1 (one row taro to one row bambara groundnut) and 1:2 intercrop
combinations. The taro UM landrace and ‘Red’ bambara groundnut landrace selection were
used in the intercropping study.
Lastly, data collected from field and rainshelter experiments were used to develop crop
parameters to calibrate and validate the FAO’s AquaCrop model for taro and bambara
groundnut landraces. The UM landrace was used for taro while the ‘Red’ landrace selection
was used for bambara groundnut. AquaCrop was calibrated using observed data from
optimum (FI) experiments conducted during 2010/11. Model validation was done using
observations from field and rainshelter experiments conducted during 2011/12 as well as
independent data.
Results showed that all taro landraces were slow to emerge (≈ 49 days after planting).
Stomatal conductance declined under conditions of limited water availability (RF, 60% and
30% ETa). The UM landrace showed better stomatal regulation compared with KW and DL
landraces under conditions of limited water availability. Plant growth (plant height, leaf
number, LAI and CCI) of taro landraces was lower under conditions of limited water
availability (RF, 60% and 30% ETa) relative to optimum conditions (FI and 100% ETa). The
UM landrace showed moderate reductions in growth compared with the DL and KW
landraces, suggesting greater adaptability to water limited conditions. The VGI showed a large
reduction in growth under RF conditions and confirmed the UM landrace’s adaptability to
limited water availability. Limited water availability (RF, 60% and 30% ETa) resulted in
lower biomass, HI, and final yield in taro landraces relative to optimum conditions (FI and
100% ETa). For all trials, the DL landrace failed to produce any yield. WUE of taro landraces
was consistent for the three irrigation levels (30, 60 and 100% ETa); however, on average, the
UM landrace was shown to have a higher WUE than the KW landrace.
Bambara groundnut landraces were slow to emerge (up to 35 days after planting). ‘Red’
and ‘Brown’ landrace selections emerged better than the ‘Light-brown’ landrace selection,
confirming the effect of seed colour on early establishment performance. Plant growth
(stomatal conductance, CCI, plant height, leaf number, LAI and biomass accumulation) was
lower under conditions of limited water availability (RF, 60% and 30% ETa) relative to
optimum conditions (FI and 100% ETa). The ‘Red’ landrace selection showed better
adaptation to stress. Limited water availability resulted in early flowering and reduced
flowering duration as well as early senescence and maturity of bambara groundnut landrace
selections. The ‘Red’ landrace selection showed delayed leaf senescence under conditions of
limited water availability. Yield reductions of up to 50% were observed under water limited
conditions (RF, 60% and 30% ETa) relative to optimum conditions (FI and 100% ETa). Water
use efficiency increased at 60% and 30% ETa, respectively, relative to 100% ETa, implying
adaptability to limited water availability. The ‘Red’ landrace selection showed better yield
stability and WUE compared with the ‘Brown’ and ‘Light-brown’ landrace selections
suggesting that seed colour may be used as a selection criterion for drought tolerance in
bambara groundnut landraces.
The intercropping study showed that intercropping, as an alternative cropping system, had
more potential than monocropping. Evaluation of growth parameters showed that taro plant
height was generally unaffected by intercropping but lower leaf number was observed as
compared with the sole crop. Bambara groundnut plants were taller and had more leaves under
intercropping relative to the sole crop. Although not statistically significant, yield was
generally lower in the intercrops compared with the sole crops. Evaluation of intercrop
productivity using the land equivalent ratio (LER) showed that intercropping taro and bambara
groundnut at a ratio of 1:1 was more productive (LER = 1.53) than intercropping at a ratio of
1:2 (LER = 1.23).
The FAO’s AquaCrop model was then calibrated for the taro UM landrace and ‘Red’
bambara groundnut landrace selection. This was based on observations from previous
experiments that suggested them to be drought tolerant and stable. Calibration results for taro
and bambara groundnut landraces showed an excellent fit between predicted and observed
parameters for canopy cover (CC), biomass and yield. Model validation for bambara
groundnut showed good model performance under field (FI and RF) conditions. Model
performance was satisfactory for rainshelters. Validation results for taro showed good model
performance under all conditions (field and rainshelters), although the model over-estimated
CC for the declining stage of canopy growth under RF conditions. Model verification using
independent data for taro showed equally good model performance.
In conclusion, the taro UM landrace and ‘Red’ bambara groundnut landrace selection were
shown to be drought tolerant and adapted to low levels of water–use. The mechanisms
responsible for drought tolerance in the taro UM landrace and ‘Red’ bambara groundnut
landrace selection were described as drought avoidance and escape. The taro UM landrace and
‘Red’ bambara groundnut landraces avoided stress through stomatal regulation, energy
dissipation (loss of chlorophyll) as well as reducing canopy size (plant height, leaf number and
LAI), which translates to minimised transpirational water losses. This indicated landrace
adaptability to low levels of water–use. The ‘Red’ bambara groundnut landrace selection
showed phenological plasticity and escaped drought by flowering early, delaying leaf
senescence, and maturing early under conditions of limited water availability. Performance of
the ‘Red’ landrace selection lends credence to the use of seed coat colour as a possible
selection criterion for drought tolerance in bambara groundnut, and possibly for other
landraces with variegated seed. The taro UM landrace escaped drought by maturing early
under conditions of limited water availability. The FAO’s AquaCrop model was successfully
calibrated and validated for taro UM and ‘Red’ bambara groundnut landraces. The calibration
and validation of AquaCrop for taro is the first such attempt and represents progress in the
modelling of neglected underutilised crops. The calibration and validation of AquaCrop for
taro requires further fine-tuning while that for bambara groundnut still needs to be tested for
more diverse landraces. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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Drought tolerance and water-use of selected South African landraces of Taro (Colocasia esculenta L. schott) and Bambara groundnut (Vigna subterranea L. Verdc)Mabhaudhi, Tafadzwanashe. 14 November 2013 (has links)
Issues surrounding water scarcity will become topical in future as global fresh water resources
become more limited thus threaten crop production. Predicted climate change and increasing
population growth will place more pressure on agriculture to produce more food using less
water. As such, efforts have now shifted to identifying previously neglected underutilised
species (NUS) as possible crops that could be used to bridge the food gap in future. Taro
(Colocasia esculenta L. Schott) and bambara groundnut (Vigna subterranea L. Verdc)
currently occupy low levels of utilisation in South Africa. Both crops are cultivated using
landraces with no improved varieties available. Information describing their agronomy and
water–use is limited and remains a bottleneck to their promotion. The aim of this study was to
determine the drought tolerance and water–use of selected landraces of taro and bambara
groundnut from KwaZulu-Natal, South Africa.
In order to meet the specific objectives for taro and bambara groundnut management, an
approach involving conventional and modelling techniques was used.
Three taro landraces [Dumbe Lomfula (DL), KwaNgwanase (KW) and Umbumbulu
(UM)] were collected from the North Coast and midlands of KwaZulu-Natal, South Africa, in
2010. The UM landrace was classified as Eddoe type taro (C. esculenta var. antiquorum)
characterised by a central corm and edible side cormels. The DL and KW landraces were
classified as Dasheen (C. esculenta var. esculenta), characterised by a large edible main corm
and smaller side cormels. A bambara groundnut landrace was collected from Jozini, KwaZulu-
Natal, and characterised into three selections (‘Red’, ‘Light-brown’ and ‘Brown’) based on
seed coat colour. Seed colour was hypothesised to have an effect on seed quality. Field and
rainshelter experiments were conducted for both taro and bambara landraces at Roodeplaat in
Pretoria and Ukulinga Research Farm in Pietermaritzburg, over two growing seasons (2010/11
and 2011/12).
The objective of the field trials for taro and bambara groundnut was to determine
mechanisms associated with drought tolerance in taro and bambara groundnut landraces.
Experiments were laid out in a split-plot design where irrigation [fully irrigated (FI) and rainfed (RF)] was the main factor and landraces (3 landraces of either taro or bambara
groundnut) were sub-factors. Treatments were arranged in a randomised complete block
design (RCBD), replicated three times. Rainfed trials were established with irrigation to allow
for maximum crop stand. Thereafter, irrigation was withdrawn. Whilst experimental designs
and layouts for taro and bambara groundnut were similar, differences existed with regards to
plot sizes and plant spacing. Trials were planted on a total land area of 500 m2 and 144 m2, for
taro and bambara groundnut, respectively. Plant spacing was 1 m x 1 m for taro and 0.3 m x
0.3 m for bambara groundnut. Irrigation scheduling in the FI treatment was based on ETo and
Kc and was applied using sprinkler irrigation system.
Separate rainshelter experiments were conducted for taro and bambara groundnut
landraces at Roodeplaat, to evaluate growth, yield and water-use of taro and bambara
groundnut landraces under a range of water regimes. The experimental design was similar for
both crops, a RCBD with two treatment factors: irrigation level [30, 60 and 100% crop water
requirement (ETa)] and landrace (3 landraces), replicated three times. Irrigation water was
applied using drip irrigation system based on ETo and Kc.
Data collection in field and rainshelter trials included time to emergence, plant height, leaf
number, leaf area index (LAI), stomatal conductance and chlorophyll content index (CCI). For
taro field trials, vegetative growth index (VGI) was also determined. Yield and yield
components (harvest index, biomass, corm number and mass) as well as water–use efficiency
(WUE) were determined at harvest.Intercropping of taro and bambara groundnut was evaluated under dryland conditions
using farmers’ fields at Umbumbulu, KwaZulu–Natal, South Africa. The experimental design
was a RCBD replicated three times. Intercrop combinations included taro and bambara
groundnut sole crops, a 1:1 (one row taro to one row bambara groundnut) and 1:2 intercrop
combinations. The taro UM landrace and ‘Red’ bambara groundnut landrace selection were
used in the intercropping study.
Lastly, data collected from field and rainshelter experiments were used to develop crop
parameters to calibrate and validate the FAO’s AquaCrop model for taro and bambara
groundnut landraces. The UM landrace was used for taro while the ‘Red’ landrace selection was used for bambara groundnut. AquaCrop was calibrated using observed data from
optimum (FI) experiments conducted during 2010/11. Model validation was done using
observations from field and rainshelter experiments conducted during 2011/12 as well as
independent data. Results showed that all taro landraces were slow to emerge (≈ 49 days after planting).
Stomatal conductance declined under conditions of limited water availability (RF, 60% and
30% ETa). The UM landrace showed better stomatal regulation compared with KW and DL
landraces under conditions of limited water availability. Plant growth (plant height, leaf
number, LAI and CCI) of taro landraces was lower under conditions of limited water
availability (RF, 60% and 30% ETa) relative to optimum conditions (FI and 100% ETa). The
UM landrace showed moderate reductions in growth compared with the DL and KW
landraces, suggesting greater adaptability to water limited conditions. The VGI showed a large
reduction in growth under RF conditions and confirmed the UM landrace’s adaptability to
limited water availability. Limited water availability (RF, 60% and 30% ETa) resulted in
lower biomass, HI, and final yield in taro landraces relative to optimum conditions (FI and
100% ETa). For all trials, the DL landrace failed to produce any yield. WUE of taro landraces
was consistent for the three irrigation levels (30, 60 and 100% ETa); however, on average, the
UM landrace was shown to have a higher WUE than the KW landrace.
Bambara groundnut landraces were slow to emerge (up to 35 days after planting). ‘Red’
and ‘Brown’ landrace selections emerged better than the ‘Light-brown’ landrace selection,
confirming the effect of seed colour on early establishment performance. Plant growth
(stomatal conductance, CCI, plant height, leaf number, LAI and biomass accumulation) was
lower under conditions of limited water availability (RF, 60% and 30% ETa) relative to
optimum conditions (FI and 100% ETa). The ‘Red’ landrace selection showed better
adaptation to stress. Limited water availability resulted in early flowering and reduced
flowering duration as well as early senescence and maturity of bambara groundnut landrace
selections. The ‘Red’ landrace selection showed delayed leaf senescence under conditions of
limited water availability. Yield reductions of up to 50% were observed under water limited
conditions (RF, 60% and 30% ETa) relative to optimum conditions (FI and 100% ETa). Water
use efficiency increased at 60% and 30% ETa, respectively, relative to 100% ETa, implying
adaptabilityto limited water availability. The ‘Red’ landrace selection showed better yield
stability and WUE compared with the ‘Brown’ and ‘Light-brown’ landrace selections
suggesting that seed colour may be used as a selection criterion for drought tolerance in
bambara groundnut landraces.
The intercropping study showed that intercropping, as an alternative cropping system, had
more potential than monocropping. Evaluation of growth parameters showed that taro plant
height was generally unaffected by intercropping but lower leaf number was observed as
compared with the sole crop. Bambara groundnut plants were taller and had more leaves under
intercropping relative to the sole crop. Although not statistically significant, yield was
generally lower in the intercrops compared with the sole crops. Evaluation of intercrop
productivity using the land equivalent ratio (LER) showed that intercropping taro and bambara
groundnut at a ratio of 1:1 was more productive (LER = 1.53) than intercropping at a ratio of
1:2 (LER = 1.23).
The FAO’s AquaCrop model was then calibrated for the taro UM landrace and ‘Red’
bambara groundnut landrace selection. This was based on observations from previous
experiments that suggested them to be drought tolerant and stable. Calibration results for taro
and bambara groundnut landraces showed an excellent fit between predicted and observed parameters for canopy cover (CC), biomass and yield. Model validation for bambara
groundnut showed good model performance under field (FI and RF) conditions. Model
performance was satisfactory for rainshelters. Validation results for taro showed good model
performance under all conditions (field and rainshelters), although the model over-estimated
CC for the declining stage of canopy growth under RF conditions. Model verification using
independent data for taro showed equally good model performance.
In conclusion, the taro UM landrace and ‘Red’ bambara groundnut landrace selection were
shown to be drought tolerant and adapted to low levels of water–use. The mechanisms
responsible for drought tolerance in the taro UM landrace and ‘Red’ bambara groundnut
landrace selection were described as drought avoidance and escape. The taro UM landrace and
‘Red’ bambara groundnut landraces avoided stress through stomatal regulation, energy
dissipation (loss of chlorophyll) as well as reducing canopy size (plant height, leaf number and
LAI), which translates to minimised transpirational water losses. This indicated landrace
viii
adaptability to low levels of water–use. The ‘Red’ bambara groundnut landrace selection showed phenological plasticity and escaped drought by flowering early, delaying leaf
senescence, and maturing early under conditions of limited water availability. Performance of
the ‘Red’ landrace selection lends credence to the use of seed coat colour as a possible
selection criterion for drought tolerance in bambara groundnut, and possibly for other
landraces with variegated seed. The taro UM landrace escaped drought by maturing early
under conditions of limited water availability. The FAO’s AquaCrop model was successfully
calibrated and validated for taro UM and ‘Red’ bambara groundnut landraces. The calibration
and validation of AquaCrop for taro is the first such attempt and represents progress in the
modelling of neglected underutilised crops. The calibration and validation of AquaCrop for
taro requires further fine-tuning while that for bambara groundnut still needs to be tested for
more diverse landraces. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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Die Wortklassen des Bambara: Bestand und AbgrenzungBrauner, Siegmund 28 May 2024 (has links)
Wie bei der traditionellen Beschreibung der meisten afrikanischen Sprachen dominierten
auch bei der des Bambara lange Zeit Vorstellungen von den Wortarten in den
(indo-)europäischen Sprachen. Erst neuere Arbeiten zu den Mande-Sprachen, so
u. a. das Kleine Wörterbuch der Bambara-Sprache von E. Ebermann (Wien 1986) und
das Dictionnaire Bambara-Français von G. D umestre (Paris, ab 1981), gehen hier
neue Wege. Auch ich habe in dem Lehrbuch des Bambara (Leipzig 1974) Vorschläge zur
Neubewertung der Wortarten bzw. der Wortklassen des Bambara unterbreitet, die
hier präzisiert und in einigen Fällen auch korrigiert werden sollen.
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Techniques agroforestières au féminin : analyse sociologique entourant la haie vive améliorée en milieu rural au Mali /Dion, Jennifer. January 2008 (has links) (PDF)
Thèse (M.A.)--Université Laval, 2008. / Bibliogr.: f. 129-137. Publié aussi en version électronique dans la Collection Mémoires et thèses électroniques.
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THE AFRONOGRAPHIC NARRATIVE: A LITERARY PRACTICE OF CULTURAL IDENTITY AND THE PRESERVATION OF MA’ATClarkson, Octavia J 08 1900 (has links)
Using Afrocentric methodologies, this dissertation argues that the Afronography, content analysis, and literally analysis of the interviews, the lives and works of Black women writers, specifically, Toni Cade Bambara, Mari Evans, Nikki Giovanni and Sonia Sanchez (BEGS), provide a model for increasing African cultural identity and ethics. As writers within this cultural movement, the Blacks Arts Movement (1965-1975) allowed BEGS to tell their stories, providing tools for their communities to build, examine and interrogate what it meant to have an African consciousness and ritualistic practice toward liberation. BEGS empowered the community in their roles as educators, mothers, and sisters, through their written literature. Additionally, they uniquely utilized their craft to promote truth, which prioritized the African principle of Maat. Thus, this study provides highlights the ways their participation within a movement holds impact and led African Americans to a practice of new rituals in America, that serves as an African continuity extending from Kemet. This inquiry defines Afrocentric Ìgbaradì, the Afronographic Narrative and extrapolates themes of Black womanhood to establish poignant aspects of the foundation established by these writers. Their influence imagined a future intellect where African art creates a narrative and regains its value to be praised through the hands of its creator rather than stolen legacies. / Africology and African American Studies
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Bambara groundnut response to controlled environment and planting date associated water stress.Sinefu, Fikile. January 2011 (has links)
Bambara groundnut is a protein-rich legume, with food security potential in drought-prone regions. It has been grown for many centuries and has remained an important crop to most African subsistence farmers. However, despite its high nutritional status and yield advantages in poor soils, it remains one of the neglected crops by science. There have now been recent efforts to study underutilised crops, with the aim of promoting them as healthy alternatives for people facing resource and environmental challenges and to contribute to food security. In order to do this, there needs to be information that can be used to advise farmers on the agronomic aspects of producing the crop. The overall aim of the study was to evaluate the response of bambara groundnut landraces to drought under controlled environment and field conditions.
Seeds were initially collected from subsistence farmers in Jozini, KwaZulu-Natal, and characterised into three seed lots distinguished by seed coat colour: red, white and brown. In the initial study (Chapter 2) seed quality of bambara groundnuts was evaluated. Seed lots were used for standard germination (SG) and cold test (CT). Seeds were germinated under two conditions, 25°C for 8 days (SG) and 4°C for 7 days followed by 8 days at 25°C (CT). Germination percentage, seedling size and mass were determined. Desiccation tolerance was evaluated by suspending 30 seeds of each seed lot over saturated salt solutions of NaCl, LiCl, KNO3 and H2O (control) for 0, 2, 4, 8, 24 and 48 hours. Five seeds were sampled at each interval and stored at -21°C for 7 days. Samples were ground and analysed for proline content.
In addition, early establishment performance of bambara groundnut was evaluated under controlled environment conditions in seedling trays using two water regimes (Chapter 2). The experimental design had three factors: seed lot (colour), priming (NaCl, LiCl, KNO3, H2O and control) and water regimes [25% and 75% Field Capacity (F.C.)]. The experiment was replicated three times. Seedling emergence was determined daily for 21 days. Seedling height and leaf number were determined weekly for three weeks, thereafter, seedling leaf area, root and shoot mass (fresh and dry), root and shoot lengths and root to shoot ratio were also determined. Seedlings were later transplanted in 90 pots for a pot trial in order to evaluate growth responses of bambara groundnut to water stress; plant height, leaf number and yield components were determined (Chapter 3).
Lastly, the use of planting date selection as a management strategy for managing the occurrence of water stress under field conditions was evaluated in field trials. The experimental design was a split-split-plot design with planting date as main factor (early, optimum and late), irrigation and rainfed as sub-main factor, and seed colour as sub-plots (brown, red and white) arranged in a randomised complete block design (RCBD), with three replications. There were three planting dates: 7 September (early planting), 24 November (optimum planting) and 19 January (late planting).
Results from Chapter 2 showed that the brown seed lot had the highest germination across treatments, followed by red and white seeds, respectively. There were significant differences between seed lots (P < 0.05) and salt solutions (P < 0.05) with respect to proline content. Seed proline content increased from 0 to 8 hours and later declined; NaCl was associated with the highest proline accumulation. There were highly significant differences (P < 0.001) between seed colours, priming treatments and F.C., as well as their interaction, with respect to seedling emergence. White seeds had the highest emergence, followed by brown and red, respectively. Priming seeds improved their emergence compared to the control, with highest emergence being observed in seeds treated with LiCl. Priming also improved emergence under water stress; 25% F.C. had the highest emergence compared to 75% F.C.
Results from Chapter 3 showed that, seeds primed with NaCl and KNO3 resulted in tallest plants with the highest number of leaves per plant. However, NaCl and KNO3 were also the most affected under water stress. Priming was shown to improve germination and early crop establishment of bambara groundnut landraces under water stress. However, yield per plant did not improve in response to either halo- or hydro-priming.
Results from field trials showed that in terms of the measured plant growth parameters (plant height, leaf number and LAI), bambara groundnut landraces were sensitive water stress. Water
stress decreased yield components, and hence yield. However, selection of planting dates was shown to be a useful management tool for managing water stress under water limited field conditions. Choice of planting date significantly affected both plant growth and yield. The optimum planting date resulted in the best crop growth for all measured plant growth parameters followed by late and early planting dates, respectively.
Seed quality was shown to be associated with seed lot colour. Darker coloured (red and brown) seeds performed better than light (white) seeds with respect to germination. Priming was also shown to improve germination and early crop establishment of bambara groundnut landraces under water stress. However, yield per plant did not improve following priming. Growth of bambara groundnut landraces was shown to be sensitive to water stress. Water stress decreased yield components and hence yield under both controlled and field conditions. Choice of planting date significantly affected both plant growth and yield. The optimum planting date was shown to be the best performing planting date.
The findings of this study suggest that bambara groundnut seed performance in terms of germination, stand establishment and productivity is associated with seed lot colour. Seed priming improves seed performance and enhances crop capacity to withstand water stress. If the optimum planting date for groundnuts (late spring to early summer) is missed, better crop performance and yield are obtained from late planting (late summer to early spring) compared with early planting (early spring). Bambara groundnut has a potential for production under water stress conditions in controlled and field environments. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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The beauty of her survival : being Black and female in Meridian, The salt eaters, Kindred, and The bluest eye /Ullrich-Ferguson, Loretta N., January 2008 (has links) (PDF)
Thesis (M.A.)--Eastern Illinois University, 2008. / Includes bibliographical references (leaves 95-103).
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Race, gender and desire narrative strategies and the production of ideology in the fiction of Toni Cade Bambara, Toni Morrison and Alice Walker /Butler-Evans, Elliott, January 1987 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 1987. / Typescript. Includes bibliographical references (leaves 284-292).
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Indigenous approaches to forecasting rainfall for adaptation of Bambara nuts (vigna subterranea) production practices in selected villages of Vhembe DistrictHlaiseka, Amukelani Eulendor 18 May 2019 (has links)
MRDV / Institute for Rural Development / This study originated from the realisation that non-conventional crops such as Bambara nuts (Vigna subterranea) were becoming increasingly important in addressing food insecurity and malnutrition in the smallholder farming sector of countries in sub-Saharan Africa. Moreover, some of the smallholder crop farmers were observed to be continuing to rely on indigenous techniques to forecast rainfall and adapt agricultural activities in response to climate variability. However, it was not clear how climate change influenced the productivity of V. subterranea. Nor were the indigenous approaches that farmers used to forecast rainfall on this phenomenon well understood. Thus, a study was carried out to identify and document indigenous approaches that smallholder farmers used to forecast rainfall and adaptation practices relating to V. subterranea. The study was conducted in Xigalo and Lambani villages located in Collins Chabane Local Municipality of Vhembe District in Limpopo Province. The villages served as case study areas that helped to compare the native approaches that the Va-Tsonga and Vha-Venda used to forecast rainfall in the course of producing V. subterranea.
A multi-case study research design, which was exploratory in nature was adopted. Convenience and snowball sampling techniques were used to identify and select respondents. The triangulation of participatory methods, techniques and tools guided the collection of qualitative data. Key informant interviews, learning circles, photovoice, one-on-one interviews and narrative inquiry techniques were applied during data collection. Smallholder farmers and the elderly members of communities were the respondents. Nine key informants in Xigalo and Lambani villages were interviewed. One retired and two currently serving government extension officers were also interviewed. Separate learning circles comprising mainly elderly men and women were also organised. Each learning circle was made up of 7-10 respondents.
Atlas.ti version 7.5.7 software was used to analyse the qualitative data following the thematic content analysis approach. It was observed that the respondents were aware of climate variability events that affected V. subterranea. Some of the events were shifts in rainfall patterns, heavy rainfall, extreme temperatures, scarcity of summer rainfall, the disappearance of lunar signs and the seasonal cycle variations. Eighteen types of phenological signs used to predict rainfall were identified. The most common signs included the Milky Way Galaxy of stars, musical sounds of birds and frogs, moon shapes, cumulus and cumulonimbus cloud types. A close relationship between conservation of V. subterranea and adaptation strategies was said to exist. It was evident that most commonly used conservation strategies were rainmaking ceremonies, planting after the summer rains, hoeing weeds, soaking seeds before planting, hilling or earthing up around the
base of the V. subterranea plant and storing the legumes in traditional vessels and sacks. The need for integrating western scientific knowledge with native forecasts to inform the production of V. subterranea was uncovered. In addition to this, the needs of Tsonga and Venda communities should inform local policy interventions. Lastly, adaptation strategies that address food insecurity with V. subterranea being part of the agro-ecosystem deserve attention in scientific investigation and policymaking. / NRF
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Knowledge of chronic complications amongst diabetic patients in the Vhembe District of Limpopo Province, South AfricaMotsharine, Selina 18 May 2018 (has links)
MCur / Department of Advanced Nursing Science / Diabetes mellitus is a global health issue affecting people of all ages. It is
defined as a non-communicable chronic disease caused by abnormal insulin
production, impaired insulin utilization or both. Its prevalence and
complications is increasing rapidly. The aim of this study was to assess
knowledge of Diabetes mellitus chronic complications among diabetic
patients in the Vhembe district of the Limpopo Province, South Africa. The
study objectives were: to assess the knowledge of Diabetes mellitus chronic
complications amongst diabetic patients; to determine the knowledge of
diabetic patients regarding self-care practice, control and management of
diabetes in the Vhembe District, and to identify challenges faced by diabetic
patients regarding chronic complications of Diabetes mellitus in the Vhembe
District
A quantitative descriptive design was used. The study population was
diabetic patients who were visiting the selected 4 hospitals, 2 health centers
and 2 clinics were in Thulamela Municipality. Convenient sampling was used
to sample 259 respondents (184(71%) females and 75(29%) males) and to
select the 8 health care services. A structured, closed-ended selfadministered
questionnaire in Tshivenda was used to collect data on the day
that diabetic patients were coming for follow-up treatment, and after they had
been attended to by the health care providers. Data were analyzed using the / NRF
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