Evaluating summer cover crop species and management strategies for rainfed maize based cropping systems in the central region of the Eastern Cape Province of South Africa
- Authors: Ganyani, Lloyd Munashe
- Date: 2011
- Subjects: No-tillage , Sustainable agriculture -- South Africa -- Eastern Cape , Rain and rainfall -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Crop Science)
- Identifier: vital:11865 , http://hdl.handle.net/10353/373 , No-tillage , Sustainable agriculture -- South Africa -- Eastern Cape , Rain and rainfall -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Agricultural systems -- South Africa -- Eastern Cape
- Description: The overall objective of the whole study was to assess whether conservation agriculture (CA) systems can work in the Eastern Cape Province (EC). The CA systems were engaged through cover cropping to address land degradation problems by emphasizing high biomass production in order to realize short term benefits such as moisture conservation, weed suppression and soil fertility benefits under rainfed conditions in the central region of the Eastern Cape province. Since rainfall is the most limiting factor to crop production in the EC, a within season rainfall distribution analysis was conducted to expose the quality of the season (onset, end and duration) and hence the feasibility of CA systems to guide agronomic decisions by farmers in EC. To assess season parameters, thirty four years of daily rainfall was collected from the University of Fort Hare Research station and used to conduct the rainy pentad (5 day rainfall totals) analysis and the daily rainfall analysis using INSTAT software programme. Based on the pentad analysis, results showed that Alice does not have a rainy season in 1 out of 2 years (50% probability) but has one in 1 out of 4 years (25% probability level). This criterion proved to be harsher and conservative when compared to the daily rainfall approach which is more precise in measuring trends on season parameters. The daily rainfall analysis indicated a 65% feasibility for the dry land cropping systems in the EC. The pentad analysis however was effective in illustrating seasonality and it showed that the wet season begins on the 1st of November, ending on the 22nd of March lasting for 140 days. Though the season duration appeared too long, the existence of dry spells during critical growth stages adversely affects the quality of the season. The daily rainfall analysis also managed to derive a signal which can guide planting decisions. For planting to be successful, this analysis determined that 20 mm of rain should be received in two consecutive days after the 1st of November. A screening trial for cover crop biomass production and weed suppression was conducted on-station Fort Hare Research Farm (32°46' S and 26° 50' E), and Msobombvu village (MSBV) (32°44' S, and 26° 55' E) over two seasons (2007/08 and 2008/09). Six summer cover crops i.e. cowpea (Vigna unguiculata), dolichos lablab (Dolichos argenteus), sunnhemp (Crotalaria juncea), buckwheat (Fagopyrum sagittatum), forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were evaluated for biomass yield, and weed suppression. Decomposition rates, moisture conservation and residual effects of these cover crops on the succeeding main crop were also evaluated under dryland conditions. The screening trial was laid in randomized complete block design replicated three times. Forage sorghum (Sorghum bicolor) and sunflower (Helianthus annus) were identified as high biomass producers and their dry matter yields ranged from 8 -12 t ha-1. These cover crops can be useful in generating high biomass in rainfed cropping systems in the EC. Other cover crops produced 3 - 4 t ha-1 of biomass which fell short of the 6 t ha-1 expected benchmark. However, these biomass yields were important in weed management since all cover crop species showed a similar degree of weed suppression which surpassed the weed fallow treatment. As dead mulches, the cover crops failed to show residual moisture conservation and weed control benefits for the succeeding maize crop mainly because of poor residue persistence, and low harvestable fallow rainfall. Buckwheat (Fagopyrum esculentum), was selected for further investigations in a follow up trial on station in 2008/09 season because of its weed smothering qualities, suitability to short cycle rotations, and possible allelopathic properties. The trial aimed at finding weed and cost effective management options of buckwheat that are none detrimental to the succeeding maize crop. Results showed that cropping systems where buckwheat is followed by a main crop may not work as they are unprofitable with respect to R100 rand invested. Though perceived to have allelopathic properties, buckwheat failed to demonstrate the possibilities of allelopathic action against weeds. Intercropping trial was conducted on-station in 2007/8-2008/09 seasons to try and find better ways of fitting legume cover crops into maize based cropping systems without compromising production of staple cereals on limited landholdings. The trials evaluated three factors in factorial combination, cover crop planting date, intercropping strategy, and cover crop species. The trial was laid as 2 x 2 x 3 factorial arranged in a split-split plot design. The main plot factor was cover crop planting date, cover crops simultaneously planted with maize and cover crop planted two weeks after planting maize (DKC 61-25). The sub-plot factor was intercropping strategy, strip intercropping and betweenrow intercropping. The sub-sub-plot factor was cover crop species, Dolichos lablab (Dolichos argenteus (Highworth), and Cowpea Vigna ungiculata (Agrinawa) plus control plots of sole maize. Results showed that same time planting of leguminous cover crops with maize using the in-between row intercropping patterns can derive appreciable system biomass (maize/cover crop) yields, utilize land efficiently whilst getting favourable maize grain yield. Based on the rainfall analysis, results showed that the probability of success when relay seeding cover crops after two weeks into standing maize is low (15% chances of success). This suggests that relay intercropping strategies would not work due to the unavailability of a good quality season.
- Full Text:
- Date Issued: 2011
An exploration into the challenges faced by rural communities in the effective use of land for subsistence agriculture for poverty alleviation: a case study of the Mpongo and Twecwana communities in the Eastern Cape
- Authors: Mlonyeni, Xolani
- Date: 2011
- Subjects: Land use -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Community Development)
- Identifier: vital:11844 , http://hdl.handle.net/10353/d1005645 , Land use -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape
- Description: The escalation of poverty simultaneously with the decline of small-scale agriculture in the rural areas of the Eastern Cape in particular, raises serious concerns within the government circles in South Africa and among researchers. Of the nine provinces of South Africa, the rate of poverty in the Eastern Cape is a pathetic one and is the largest contributor to poverty statistics in the whole of South Africa. Machete (2004) stresses that high levels of poverty are visible in the rural areas and the large proportions of the people who are poor in South Africa are found in the rural areas. It is widely accepted that small-scale agriculture plays a vital role in and contributes substantially to socio-economic life of people living in the rural areas and is one of the strategies most suited to combat poverty for the majority of the people in the rural areas. This study explored the challenges that limit the effective use of land for subsistence agriculture as a strategy for poverty alleviation at Mpongo and Twecwana villages in Tsholomnqa. The study adopted a qualitative approach in order to get in-depth understanding of the challenges as experienced by the participants. The sample comprised of fifteen (15) subsistence farmers and three (3) extension officers from the department of agriculture. The data was collected from the participants through the focus group technique with an interview schedule containing open ended questions. The findings of the study indicated that the communities lack capital such as money, machinery, labour and other resources needed to pursue agricultural livelihoods. The findings also showed that agricultural infrastructure such as dams, rivers, fencing have deteriorated. Machete (2004, p.8) concurring with Pote (2008) says “inadequate physical infrastructure in the rural areas, particular in the former homeland areas remains a major obstacle to smallholder agricultural growth in South Africa”. In the two villages the situation is worsened by a total lack of irrigation scheme development. These communities rely entirely on seasonal and natural rainfall for their crops to be cultivated and grown. It was also found that the introduction of state grants contributed for the rural communities to do way with their traditional socio-economic agricultural livelihoods. The end results were for food production from gardens and communal fields come to a total collapse in many communities in the rural areas. The findings also show that youth is less interested to participate and pursue agricultural based activities in the rural areas. Williams et al (2008) claim that young people are unwilling to pursue agricultural studies as career of choice because of negative image attached to it. Many youths regard agriculture as an activity which belongs to adult and ordinary people. Drought was also cited as the worst natural disaster that has threatened the already disadvantaged small scale agriculture in these rural areas. These deficiencies have rendered subsistence agricultural centred activities to a total collapse.
- Full Text:
- Date Issued: 2011