Animal manure is a key input for soil fertility management among small-scale crop farmers in Sout... more Animal manure is a key input for soil fertility management among small-scale crop farmers in South Africa. However, one of the misgivings that farmers have about the use of fresh animal manure in crop fields is that it encourages growth and proliferation of diverse weed species. Cattle, goat and sheep manure was aerobically composted in windrows over a 10-week period and the emergence and species diversity of weeds were compared with that of un-composted manure. Composting reduced the total number of weeds by an average of 66.3%, 85.1% and 84.2% in cattle, goat and sheep manure, respectively. There were on average six broadleaved weeds to one grass weed emerging in the composted manure. Composting reduced the diversity of weed species by 62% across the three manure types. The highest reduction in species composition was observed in sheep (75%) and goat (67%) manures compared to cattle (40%) manure. There were no grass weed species in the composted goat and sheep manures. The study c...
African Journal of Agricultural Research, Aug 18, 2011
The study quantified the salinity in profiles of urban agriculture soils irrigated using sprinkle... more The study quantified the salinity in profiles of urban agriculture soils irrigated using sprinkler, basin and drip methods for 15 years compared with rainfed conditions. The ANOVA showed significant influence (p < 0.05) of both irrigation methods and soil depth on the amount of soluble salts, pH and electrical conductivity (ECe) of the soils. Irrigation methods significantly increased (p < 0.05) the salt concentration (mg/kg) within the profile compared to the control for Ca 2+ (792 vs 464), Mg 2+ (398 vs 196), K + (274 vs 164), Na + (19.3 vs 9.8), pH (7.13 vs 6.3) and ECe (22.1 vs 7.9 dS/m). Except for Na, the concentrations of Ca, Mg and K were higher in the top than subsoil layers while pH and ECe were not significantly different. Basin irrigation had consistently accumulated highest amounts of Ca, Mg, K and Na followed by drip and sprinkler method. The pattern for pH and EC was basin > drip > sprinkler > control. Sprinkler irrigation was the only method which showed increased pH and ECe at 10 to 20 cm compared to 0 to 10 cm depth. It was concluded that irrigation was increasing salinity in the soils and points to the need for adherence to sound irrigation water management practices especially appropriate irrigation scheduling.
African indigenous leafy vegetables have the important role of providing essential minerals, vita... more African indigenous leafy vegetables have the important role of providing essential minerals, vitamins and amino acids in diets of poor smallholder farmer households in sub-Saharan Africa. A study was conducted to quantify the influence of applying cattle and goat manure on the biomass yields and crude protein content of two commonly used African leafy vegetables (Cleome gynandra and Amaranthus hybridus) when subjected to varying leaf cutting management. Treatments for each vegetable consisted of a combination of three manures (control, cattle and goat) and three cutting regimes (cutting edible leaves, all harvestable leaves and cut only at the end) utilised in randomised block design. The results showed significant increase in leaf biomass yields and crude protein content of both vegetables due to manure application. Goat manure was superior to cattle manure due to its higher quality in terms of nutrient content and lower C:N ratio. Cutting the edible leaves more frequently, every f...
The effects of Aloe ferox, Agave sisalana and Gunnera perpensa on haematological and biochemical ... more The effects of Aloe ferox, Agave sisalana and Gunnera perpensa on haematological and biochemical parameters of village chickens naturally infected with Heterakis gallinarum were evaluated. One hundred and twelve mature village chickens were randomly allotted into 14 groups of 8 chickens. Group 1 and 2 were orally administered 1 mL distilled water for 4 consecutive days and 1 mL mebendazole (once), respectively. Groups 3-6 received 1 mL orally of aqueous leaf extract of A. ferox for 4 consecutive days, groups 7-10 A. sisalana and 11-14 G. perpensa in graded doses of 50, 100, 200 and 400 mg/kg, respectively. Blood was collected into vacutainers in triplicate, from the wing veins on day 0, 7 and 14. Data was analysed using general linear model of statistical analyses system. Chickens offered A. sisalana (200 mg/kg) had highest alanine transaminase (ALT) value (P < 0.05; 7.50 ± 0.406 U/l) on day 0. On day 7 and 14, there was no difference in ALT values (P >0.05). Significant diffe...
Ridge-tillage is a traditional method of seedbed preparation in Malawi and is performed annually ... more Ridge-tillage is a traditional method of seedbed preparation in Malawi and is performed annually by manual operation with a hand hoe. A 3-year field experiment was conducted to evaluate the effects of minimum (MT) and conventional (CT) ridge-tillage systems on soil strength and maize (Zen mays L.) growth. Minimum tillage consisted of planting maize on ridges made in the previous year(s) while in CT it was grown on new ridges constructed at the beginning of each season. The soil was an Oxic Rhodustalf. Results indicated that a distinct hard and compact layer had developed below the ridges (about 2.5 cm depth) in both CT and MT. Soil on ridges of CT had consistently lower penetration resistance than did MT. Bulk density and penetration resistance of soil on the ridges were less under CT than under MT. Penetration resistance in both tillage treatments was strongly related to soil water content, which depended on the amount of rainfall. Consequently, the pattern in changes of penetration resistance in thq soil during the season generally mirrored that of rainfall. The presence of compacted subsurface soil layers in both treatments and the significantly higher (P I 0.05) penetration resistance in the MT affected root penetration and distribution. The MT had significantly lower root length density in the O-20 cm depth and roots were concentrated near the surface compared with those of CT. Maize grain yields, however, were not affected by the tillage system in the first two seasons of the study but were significantly reduced by MT in the third season. The average grain yields over the three seasons were 4812 and 4644 kg ha-' for CT and MT, respectively. Use of MT resulted in remarkable reductions of working time and energy requirement for maize production compared
Depth of sowing can affect early crop establishment due to poor seedling emergence. A glasshouse ... more Depth of sowing can affect early crop establishment due to poor seedling emergence. A glasshouse study was conducted to investigate the effects of sowing depths (1.5, 3.5, 7, 10, 15, 20, 25, 30 mm) on emergence and early seedling development of two each of African indigenous (Amaranthus hybridus & Cleome gynandra) and exotic (Spinacia oleracea & Brassica napus) leafy vegetables. A split plot design with four replicates was used. Exotic vegetables had significantly higher (p<0.05) seedling emergence (95%) than the indigenous ones (60%). Among the indigenous species, Cleome gynandra had a higher emergence (70%) than Amaranthus hybridus (61%). However, there were no significant differences on emergence amongst the exotic vegetables. Exotic vegetables also had significantly higher (p<0.05) mean plant height (8.6 cm) than indigenous vegetables (1.01 cm). In all the vegetable species, both emergence and plant height decreased with deeper sowing due to higher soil strength. The biomass yields of the seedlings were reduced with deeper sowing although the differences were not significant. There were however significant differences (p<0.05) among the biomass yields of the vegetable species at different sowing depths. Generally, significantly higher biomass yields (6.4 g/plant) were obtained in exotic species compared with indigenous ones (0.2 g/plant). The results suggest that seeds of African indigenous leafy vegetables were more sensitive than the exotic ones to deeper (>5 mm) sowing and their emergence was more adversely affected by soil strength at this depth. It is concluded that seeds of African indigenous vegetables should be sown at shallower depths (1-5 mm) in order to ensure rapid emergence and early establishment of seedlings if sown directly into the soil.
SUMMARYChicken manure is a potential source of plant available phosphorous (P) and this field stu... more SUMMARYChicken manure is a potential source of plant available phosphorous (P) and this field study explored its use for dry land maize production in a soil with very low inherent P levels. The treatments consisted of applying 0, 20, 40 and 80 kg P ha−1 each from chicken manure (2.3% P), inorganic fertilizer (single super phosphate, 10.5% P) and a combination of manure and fertilizer. The treatments were replicated four times in a randomized complete block design over two crop seasons. The results revealed that maize growth and yield responded to the P from both manure and fertilizer compared to the control. There were significantly (p < 0.05) taller plants and yield (grain and biomass) in maize supplied with P than control. At each level of P application however, the response was higher for fertilizer than manure. The combination of manure and inorganic fertilizer produced results that were in the middle. There were strong indications that application of chicken manure was assoc...
Communications in Soil Science and Plant Analysis, 2002
The study was conducted to determine the effects of applying wood-ash to two soils amended with p... more The study was conducted to determine the effects of applying wood-ash to two soils amended with partially-decomposed cattle and chicken manure on the uptake of nutrients, early growth and dry matter yields of maize (Zea mays L.). A clay and silty loam soil was used. Manure was applied to each soil in pots at rates equivalent to 0, 5, and
Partnerships between government, the private sector and civil society are critical for any sustai... more Partnerships between government, the private sector and civil society are critical for any sustainable development agenda. However, experience in Africa has shown that participation by local communities in development projects is rarely interactive or empowering. The crux of community engagement and partnership is that it should be inclusive, responsive, equitable and ethical. This chapter argues that indigenous communities of practice (iCoPs) provide a platform where the voices, rights, knowledge and experiences of local communities could be heard, respected and negotiated in development agendas. An indigenous community of practice is developed, acquired and owned by a close group of people who are usually ethnically or culturally linked and use indigenous knowledge to address problems in order to survive. iCoPs are largely products of local indigenous knowledge and governance systems. The chapter uses a thematic analysis of two South African iCoPs to illustrate how the principles,...
The majority of rural population in Sub-Saharan Africa (SSA) rely on smallholder agriculture to w... more The majority of rural population in Sub-Saharan Africa (SSA) rely on smallholder agriculture to wade off hunger, food insecurity and undernourishment. Sustainable agriculture focusses on producing crops and livestock on a long-term basis while having minimal effects on the environment. This chapter argues that African Indigenous Knowledge systems (AIKS) affords the knowledge, practices, innovation and technologies that can contribute to the sustainability of agriculture. It is generally acknowledged that all indigenous knowledges have an inherent organic sustainability norms as they have sustained communities over many years. This chapter highlights some features of AIKS which gives it salient relevance to sustainable agriculture. It examines cases and experiences from AIKS to elucidate that components of sustainability in food production such as resilience, genetic diversity and yield stability are present in the traditional agricultural systems. Examples of indigenous ways of know...
Woody plant encroachment is recognised as one of the major threats to biodiversity in ecosystems.... more Woody plant encroachment is recognised as one of the major threats to biodiversity in ecosystems. In many arid and semiarid areas of South Africa, indigenous encroacher species are proliferating, but the factors that favor their abundance are poorly understood. This study investigated the effect of encroaching woody species on soil properties. The effects of two encroaching species, Senegalia mellifera and Dichrostachys cinerea, on soil nutrients and chemical properties were investigated in 8 communally managed grazing sites and compared to the effects of the non-encroacher, Vachellia karroo, in two non-encroached benchmark sites. Three belt transects were laid out to determine woody plant density. Three soil samples (0-20 cm deep) per belt were sampled to determine soil properties. Senegalia mellifera was the most abundant with a mean density of 5907 TE ha−1. Soil properties in the benchmark sites had no significant differences (p > 0.05) than soil under encroaching D. cinerea regarding organic C, total N, C:N, exchangeable Na, CEC, EC, ESP, SAR and soil texture. Plant influence on soil differed among encroaching species and between encroaching and non-encroaching species. Plant diversity explain the variation of soil properties and prove the important specific role of each species in the ecosystem.
The use of medicinal plants for contraception remains a common practice among South African ethni... more The use of medicinal plants for contraception remains a common practice among South African ethnic groups. The present study assessed the phytochemical profile, cytotoxicity, acute oral toxicity and efficacy of a herbal mixture used for contraception by the Batswana of South Africa. An aqueous extract was prepared from equal quantities (in terms of weight) of Bulbine frutescens (roots), Helichrysum caespititium (leaves) and Teucrium trifidum (leaves) based on a recipe used by traditional health practitioners. The phytochemical profiles of the freeze-dried herbal mixture were analyzed using gas chromatography–mass spectrometry (GC-MS). In addition, cytotoxicity was determined using an MTT assay on Vero cells and in vivo contraceptive efficacy was evaluated using seven Sprague Dawley rats per control and treatment groups. The control group received distilled water while test groups received 5, 50 and 300 mg/kg of the herbal mixture, which was administered orally once a day for three c...
Abstract: The study was conducted to compare the influence of seed size and soil strength on germ... more Abstract: The study was conducted to compare the influence of seed size and soil strength on germination and emergence of cereal and legume seedlings in a hardsetting soil. The seed weights (g 100 -1 seeds) of the plant species were 45.5 (maize), 4.5 (wheat), 2.5 (sorghum), 3.1 (oats), 0.54 (millet), 46.95 (bambaranut), 19.82 (cowpea), 3.13 (peas) and 45.14 (groundnut). Seedlings of each of the crop species were exposed to soil strengths of 1.2 and 2.4 kg /cm 2 . This was achieved by sowing seeds at depths of 2.5 and 5.0 cm for 1.2 and 2.4 kg/cm 2 respectively. Emergence of seedlings was generally high in cereals (96%) than in legumes (56%). The emergence was in the order: sorghum (99.2%) > oats (96.7%) > millet (96.7%) > wheat (95.8%) > maize (87.5%) > cowpea (56.7%) > bambaranut (54.0%) > groundnut (34.2%) > pea (20.0%). The mean emergence percentage for the two soil strength levels were 88.0% and 52.5% for soil strengths of 1.2 kg/cm 2 and 2.4 kg/cm 2 resp...
Improved food crop production is the central strategy for achieving household food security in ma... more Improved food crop production is the central strategy for achieving household food security in many countries of the Sub-Saharan Africa. Leaf litter biomass, especially from leguminous plants is commonly used in smallholder farmers’ agroforestry systems to improve and maintain soil fertility. In this study leaf litter from three fruit trees commonly found in the sub-tropical environment of South Africa was used to quantify the uptake of nutrients by maize grown in soil amended with the litter. Leaf litter from trees of avocado (Persea americana L.), mango (Mangifera indica L.) and litchi (Litchi chinensis L.) was applied at rates equivalent to 0, 1.6 and 3.3 t ha -1 and incubated for periods of 0, 6 and 12 months before planting. Dry matter yields of maize were significantly (p<0.01) higher in soil amended with 3.3 t ha -1 of P. americana leaf litter while the lowest yields were obtained in soils amended with M. indica leaf litter. The uptake of P was higher in shoots than roots ...
Being the case with many other countries in sub-Saharan Africa, crop production among small scale... more Being the case with many other countries in sub-Saharan Africa, crop production among small scale farmers, especially those in semi-arid regions of South Africa, is hampered by predominance of extreme climate (low, irregular and erratic rainfall), low inherent soil fertility and low use of mineral fertilizers. However, small-scale farmers have developed a range of indigenous knowledge and practices which have played a pivotal role in the management of soil fertility for sustaining crop productivity. This study sought to establish and document these strategies in four farming districts located in semi-arid areas of the country. It was found that farmers use locally adaptable and cost effective strategies including animal manure, ash from veld fire, agroforestry, fallow, termitaria and earthworm castings to manage soil fertility. Some of these strategies were applied in specific niche locations and soils, times and crops. Furthermore, farmers have developed local knowledge and criteri...
A total of 150 farmers were interviewed using a str uctured questionnaire to collect information ... more A total of 150 farmers were interviewed using a str uctured questionnaire to collect information on the ir socio-economic profiles and how it influenced the u tilization of leaf litter biomass from sub-tropical fruit trees for maintaining soil fertility. Descriptive s tatistics and dichotomous binary logit models were used to analyse data. The results showed that 95% of the farmers use leaf litter for maintaining soil ferti lity on their fields. About 70% of the respondent farmer s mixed leaf litter with amendments such as kraal and chicken manure in order to improve its nutrient content quality. Composting was also used by the farmers as a technique to improve the quality of le af litter. The results of the logit model correctly classified 83% of the farmers that used leaf litter for maintaining soil fertility. The estimates of t he maximum likelihood for leaf litter biomass utilizat ion by farmers were increased in the order of land tenure (1.35ns) > labour (1.15ns) > age (0...
Animal manure is a key input for soil fertility management among small-scale crop farmers in Sout... more Animal manure is a key input for soil fertility management among small-scale crop farmers in South Africa. However, one of the misgivings that farmers have about the use of fresh animal manure in crop fields is that it encourages growth and proliferation of diverse weed species. Cattle, goat and sheep manure was aerobically composted in windrows over a 10-week period and the emergence and species diversity of weeds were compared with that of un-composted manure. Composting reduced the total number of weeds by an average of 66.3%, 85.1% and 84.2% in cattle, goat and sheep manure, respectively. There were on average six broadleaved weeds to one grass weed emerging in the composted manure. Composting reduced the diversity of weed species by 62% across the three manure types. The highest reduction in species composition was observed in sheep (75%) and goat (67%) manures compared to cattle (40%) manure. There were no grass weed species in the composted goat and sheep manures. The study c...
African Journal of Agricultural Research, Aug 18, 2011
The study quantified the salinity in profiles of urban agriculture soils irrigated using sprinkle... more The study quantified the salinity in profiles of urban agriculture soils irrigated using sprinkler, basin and drip methods for 15 years compared with rainfed conditions. The ANOVA showed significant influence (p < 0.05) of both irrigation methods and soil depth on the amount of soluble salts, pH and electrical conductivity (ECe) of the soils. Irrigation methods significantly increased (p < 0.05) the salt concentration (mg/kg) within the profile compared to the control for Ca 2+ (792 vs 464), Mg 2+ (398 vs 196), K + (274 vs 164), Na + (19.3 vs 9.8), pH (7.13 vs 6.3) and ECe (22.1 vs 7.9 dS/m). Except for Na, the concentrations of Ca, Mg and K were higher in the top than subsoil layers while pH and ECe were not significantly different. Basin irrigation had consistently accumulated highest amounts of Ca, Mg, K and Na followed by drip and sprinkler method. The pattern for pH and EC was basin > drip > sprinkler > control. Sprinkler irrigation was the only method which showed increased pH and ECe at 10 to 20 cm compared to 0 to 10 cm depth. It was concluded that irrigation was increasing salinity in the soils and points to the need for adherence to sound irrigation water management practices especially appropriate irrigation scheduling.
African indigenous leafy vegetables have the important role of providing essential minerals, vita... more African indigenous leafy vegetables have the important role of providing essential minerals, vitamins and amino acids in diets of poor smallholder farmer households in sub-Saharan Africa. A study was conducted to quantify the influence of applying cattle and goat manure on the biomass yields and crude protein content of two commonly used African leafy vegetables (Cleome gynandra and Amaranthus hybridus) when subjected to varying leaf cutting management. Treatments for each vegetable consisted of a combination of three manures (control, cattle and goat) and three cutting regimes (cutting edible leaves, all harvestable leaves and cut only at the end) utilised in randomised block design. The results showed significant increase in leaf biomass yields and crude protein content of both vegetables due to manure application. Goat manure was superior to cattle manure due to its higher quality in terms of nutrient content and lower C:N ratio. Cutting the edible leaves more frequently, every f...
The effects of Aloe ferox, Agave sisalana and Gunnera perpensa on haematological and biochemical ... more The effects of Aloe ferox, Agave sisalana and Gunnera perpensa on haematological and biochemical parameters of village chickens naturally infected with Heterakis gallinarum were evaluated. One hundred and twelve mature village chickens were randomly allotted into 14 groups of 8 chickens. Group 1 and 2 were orally administered 1 mL distilled water for 4 consecutive days and 1 mL mebendazole (once), respectively. Groups 3-6 received 1 mL orally of aqueous leaf extract of A. ferox for 4 consecutive days, groups 7-10 A. sisalana and 11-14 G. perpensa in graded doses of 50, 100, 200 and 400 mg/kg, respectively. Blood was collected into vacutainers in triplicate, from the wing veins on day 0, 7 and 14. Data was analysed using general linear model of statistical analyses system. Chickens offered A. sisalana (200 mg/kg) had highest alanine transaminase (ALT) value (P < 0.05; 7.50 ± 0.406 U/l) on day 0. On day 7 and 14, there was no difference in ALT values (P >0.05). Significant diffe...
Ridge-tillage is a traditional method of seedbed preparation in Malawi and is performed annually ... more Ridge-tillage is a traditional method of seedbed preparation in Malawi and is performed annually by manual operation with a hand hoe. A 3-year field experiment was conducted to evaluate the effects of minimum (MT) and conventional (CT) ridge-tillage systems on soil strength and maize (Zen mays L.) growth. Minimum tillage consisted of planting maize on ridges made in the previous year(s) while in CT it was grown on new ridges constructed at the beginning of each season. The soil was an Oxic Rhodustalf. Results indicated that a distinct hard and compact layer had developed below the ridges (about 2.5 cm depth) in both CT and MT. Soil on ridges of CT had consistently lower penetration resistance than did MT. Bulk density and penetration resistance of soil on the ridges were less under CT than under MT. Penetration resistance in both tillage treatments was strongly related to soil water content, which depended on the amount of rainfall. Consequently, the pattern in changes of penetration resistance in thq soil during the season generally mirrored that of rainfall. The presence of compacted subsurface soil layers in both treatments and the significantly higher (P I 0.05) penetration resistance in the MT affected root penetration and distribution. The MT had significantly lower root length density in the O-20 cm depth and roots were concentrated near the surface compared with those of CT. Maize grain yields, however, were not affected by the tillage system in the first two seasons of the study but were significantly reduced by MT in the third season. The average grain yields over the three seasons were 4812 and 4644 kg ha-' for CT and MT, respectively. Use of MT resulted in remarkable reductions of working time and energy requirement for maize production compared
Depth of sowing can affect early crop establishment due to poor seedling emergence. A glasshouse ... more Depth of sowing can affect early crop establishment due to poor seedling emergence. A glasshouse study was conducted to investigate the effects of sowing depths (1.5, 3.5, 7, 10, 15, 20, 25, 30 mm) on emergence and early seedling development of two each of African indigenous (Amaranthus hybridus & Cleome gynandra) and exotic (Spinacia oleracea & Brassica napus) leafy vegetables. A split plot design with four replicates was used. Exotic vegetables had significantly higher (p<0.05) seedling emergence (95%) than the indigenous ones (60%). Among the indigenous species, Cleome gynandra had a higher emergence (70%) than Amaranthus hybridus (61%). However, there were no significant differences on emergence amongst the exotic vegetables. Exotic vegetables also had significantly higher (p<0.05) mean plant height (8.6 cm) than indigenous vegetables (1.01 cm). In all the vegetable species, both emergence and plant height decreased with deeper sowing due to higher soil strength. The biomass yields of the seedlings were reduced with deeper sowing although the differences were not significant. There were however significant differences (p<0.05) among the biomass yields of the vegetable species at different sowing depths. Generally, significantly higher biomass yields (6.4 g/plant) were obtained in exotic species compared with indigenous ones (0.2 g/plant). The results suggest that seeds of African indigenous leafy vegetables were more sensitive than the exotic ones to deeper (>5 mm) sowing and their emergence was more adversely affected by soil strength at this depth. It is concluded that seeds of African indigenous vegetables should be sown at shallower depths (1-5 mm) in order to ensure rapid emergence and early establishment of seedlings if sown directly into the soil.
SUMMARYChicken manure is a potential source of plant available phosphorous (P) and this field stu... more SUMMARYChicken manure is a potential source of plant available phosphorous (P) and this field study explored its use for dry land maize production in a soil with very low inherent P levels. The treatments consisted of applying 0, 20, 40 and 80 kg P ha−1 each from chicken manure (2.3% P), inorganic fertilizer (single super phosphate, 10.5% P) and a combination of manure and fertilizer. The treatments were replicated four times in a randomized complete block design over two crop seasons. The results revealed that maize growth and yield responded to the P from both manure and fertilizer compared to the control. There were significantly (p < 0.05) taller plants and yield (grain and biomass) in maize supplied with P than control. At each level of P application however, the response was higher for fertilizer than manure. The combination of manure and inorganic fertilizer produced results that were in the middle. There were strong indications that application of chicken manure was assoc...
Communications in Soil Science and Plant Analysis, 2002
The study was conducted to determine the effects of applying wood-ash to two soils amended with p... more The study was conducted to determine the effects of applying wood-ash to two soils amended with partially-decomposed cattle and chicken manure on the uptake of nutrients, early growth and dry matter yields of maize (Zea mays L.). A clay and silty loam soil was used. Manure was applied to each soil in pots at rates equivalent to 0, 5, and
Partnerships between government, the private sector and civil society are critical for any sustai... more Partnerships between government, the private sector and civil society are critical for any sustainable development agenda. However, experience in Africa has shown that participation by local communities in development projects is rarely interactive or empowering. The crux of community engagement and partnership is that it should be inclusive, responsive, equitable and ethical. This chapter argues that indigenous communities of practice (iCoPs) provide a platform where the voices, rights, knowledge and experiences of local communities could be heard, respected and negotiated in development agendas. An indigenous community of practice is developed, acquired and owned by a close group of people who are usually ethnically or culturally linked and use indigenous knowledge to address problems in order to survive. iCoPs are largely products of local indigenous knowledge and governance systems. The chapter uses a thematic analysis of two South African iCoPs to illustrate how the principles,...
The majority of rural population in Sub-Saharan Africa (SSA) rely on smallholder agriculture to w... more The majority of rural population in Sub-Saharan Africa (SSA) rely on smallholder agriculture to wade off hunger, food insecurity and undernourishment. Sustainable agriculture focusses on producing crops and livestock on a long-term basis while having minimal effects on the environment. This chapter argues that African Indigenous Knowledge systems (AIKS) affords the knowledge, practices, innovation and technologies that can contribute to the sustainability of agriculture. It is generally acknowledged that all indigenous knowledges have an inherent organic sustainability norms as they have sustained communities over many years. This chapter highlights some features of AIKS which gives it salient relevance to sustainable agriculture. It examines cases and experiences from AIKS to elucidate that components of sustainability in food production such as resilience, genetic diversity and yield stability are present in the traditional agricultural systems. Examples of indigenous ways of know...
Woody plant encroachment is recognised as one of the major threats to biodiversity in ecosystems.... more Woody plant encroachment is recognised as one of the major threats to biodiversity in ecosystems. In many arid and semiarid areas of South Africa, indigenous encroacher species are proliferating, but the factors that favor their abundance are poorly understood. This study investigated the effect of encroaching woody species on soil properties. The effects of two encroaching species, Senegalia mellifera and Dichrostachys cinerea, on soil nutrients and chemical properties were investigated in 8 communally managed grazing sites and compared to the effects of the non-encroacher, Vachellia karroo, in two non-encroached benchmark sites. Three belt transects were laid out to determine woody plant density. Three soil samples (0-20 cm deep) per belt were sampled to determine soil properties. Senegalia mellifera was the most abundant with a mean density of 5907 TE ha−1. Soil properties in the benchmark sites had no significant differences (p > 0.05) than soil under encroaching D. cinerea regarding organic C, total N, C:N, exchangeable Na, CEC, EC, ESP, SAR and soil texture. Plant influence on soil differed among encroaching species and between encroaching and non-encroaching species. Plant diversity explain the variation of soil properties and prove the important specific role of each species in the ecosystem.
The use of medicinal plants for contraception remains a common practice among South African ethni... more The use of medicinal plants for contraception remains a common practice among South African ethnic groups. The present study assessed the phytochemical profile, cytotoxicity, acute oral toxicity and efficacy of a herbal mixture used for contraception by the Batswana of South Africa. An aqueous extract was prepared from equal quantities (in terms of weight) of Bulbine frutescens (roots), Helichrysum caespititium (leaves) and Teucrium trifidum (leaves) based on a recipe used by traditional health practitioners. The phytochemical profiles of the freeze-dried herbal mixture were analyzed using gas chromatography–mass spectrometry (GC-MS). In addition, cytotoxicity was determined using an MTT assay on Vero cells and in vivo contraceptive efficacy was evaluated using seven Sprague Dawley rats per control and treatment groups. The control group received distilled water while test groups received 5, 50 and 300 mg/kg of the herbal mixture, which was administered orally once a day for three c...
Abstract: The study was conducted to compare the influence of seed size and soil strength on germ... more Abstract: The study was conducted to compare the influence of seed size and soil strength on germination and emergence of cereal and legume seedlings in a hardsetting soil. The seed weights (g 100 -1 seeds) of the plant species were 45.5 (maize), 4.5 (wheat), 2.5 (sorghum), 3.1 (oats), 0.54 (millet), 46.95 (bambaranut), 19.82 (cowpea), 3.13 (peas) and 45.14 (groundnut). Seedlings of each of the crop species were exposed to soil strengths of 1.2 and 2.4 kg /cm 2 . This was achieved by sowing seeds at depths of 2.5 and 5.0 cm for 1.2 and 2.4 kg/cm 2 respectively. Emergence of seedlings was generally high in cereals (96%) than in legumes (56%). The emergence was in the order: sorghum (99.2%) > oats (96.7%) > millet (96.7%) > wheat (95.8%) > maize (87.5%) > cowpea (56.7%) > bambaranut (54.0%) > groundnut (34.2%) > pea (20.0%). The mean emergence percentage for the two soil strength levels were 88.0% and 52.5% for soil strengths of 1.2 kg/cm 2 and 2.4 kg/cm 2 resp...
Improved food crop production is the central strategy for achieving household food security in ma... more Improved food crop production is the central strategy for achieving household food security in many countries of the Sub-Saharan Africa. Leaf litter biomass, especially from leguminous plants is commonly used in smallholder farmers’ agroforestry systems to improve and maintain soil fertility. In this study leaf litter from three fruit trees commonly found in the sub-tropical environment of South Africa was used to quantify the uptake of nutrients by maize grown in soil amended with the litter. Leaf litter from trees of avocado (Persea americana L.), mango (Mangifera indica L.) and litchi (Litchi chinensis L.) was applied at rates equivalent to 0, 1.6 and 3.3 t ha -1 and incubated for periods of 0, 6 and 12 months before planting. Dry matter yields of maize were significantly (p<0.01) higher in soil amended with 3.3 t ha -1 of P. americana leaf litter while the lowest yields were obtained in soils amended with M. indica leaf litter. The uptake of P was higher in shoots than roots ...
Being the case with many other countries in sub-Saharan Africa, crop production among small scale... more Being the case with many other countries in sub-Saharan Africa, crop production among small scale farmers, especially those in semi-arid regions of South Africa, is hampered by predominance of extreme climate (low, irregular and erratic rainfall), low inherent soil fertility and low use of mineral fertilizers. However, small-scale farmers have developed a range of indigenous knowledge and practices which have played a pivotal role in the management of soil fertility for sustaining crop productivity. This study sought to establish and document these strategies in four farming districts located in semi-arid areas of the country. It was found that farmers use locally adaptable and cost effective strategies including animal manure, ash from veld fire, agroforestry, fallow, termitaria and earthworm castings to manage soil fertility. Some of these strategies were applied in specific niche locations and soils, times and crops. Furthermore, farmers have developed local knowledge and criteri...
A total of 150 farmers were interviewed using a str uctured questionnaire to collect information ... more A total of 150 farmers were interviewed using a str uctured questionnaire to collect information on the ir socio-economic profiles and how it influenced the u tilization of leaf litter biomass from sub-tropical fruit trees for maintaining soil fertility. Descriptive s tatistics and dichotomous binary logit models were used to analyse data. The results showed that 95% of the farmers use leaf litter for maintaining soil ferti lity on their fields. About 70% of the respondent farmer s mixed leaf litter with amendments such as kraal and chicken manure in order to improve its nutrient content quality. Composting was also used by the farmers as a technique to improve the quality of le af litter. The results of the logit model correctly classified 83% of the farmers that used leaf litter for maintaining soil fertility. The estimates of t he maximum likelihood for leaf litter biomass utilizat ion by farmers were increased in the order of land tenure (1.35ns) > labour (1.15ns) > age (0...
Uploads
Papers by S. Materechera