National Research Institutions

Water is the main factor affecting crop production in sub-Saharan Africa. It was hypothesized that intercropping sorghum (S) with either cowpea (C) or bottle gourd (B) would result in better productivity and water use efficiency (WUE). This was evaluated using a split-plot design with sub-plots arranged in a randomised complete block manner within the main plot, replicated thrice. Water regimes [full irrigation (FI), deficit irrigation (DI) and rainfed (RF)] were allocated to the main plots. Sub-plots comprised intercrop combinations, SS (sole), C (sole), B (sole), SC (intercrop) and SB (intercrop). Data collected included soil water content (SWC), plant height (PH)/vine length, leaf number (LN), tillering (T)/branching, leaf area index (LAI), relative leaf water content (RWC), stomatal conductance (gs) and chlorophyll content index (CCI) as well as biomass accumulation and partitioning. Yield and yield components, water use (WU) and WUE for grain (WUEg) were calculated at harvest. Land equivalent ratio (LER) was used to evaluate productivity of the intercrop. Sorghum canopy size decreased (P < 0.05) (−6.7%, −10.6%, −89% and −79% for PH, LN, T and LAI, respectively) with decreasing water availability. Sorghum growth and development were unaffected by intercropping. Intercropping sorghum with cowpea improved gs (23%) and CCI (6.56%) of sorghum under low water availability. Productivity of sorghum across varying water regimes and cropping systems was stable with final biomass, yield and harvest index of 2.4 t ha−1, 0.98 t ha−1 and 35%, respectively. Overall, LER showed a 46% increase in productivity across all intercrop systems. Intercropping marginally increased WU (5.64%). Improvements of WUEg were observed under SC and SB (54.65% and 46.98%, respectively) relative to SS. Intercropping sorghum with cowpea is recommended for semi-and arid environments since it promoted efficient use of water.

Farmers who still cultivate bambara groundnut (Vigna subterranea) rely on landraces and seed retained from previous harvests. Given that the crop is typically cultivated in semi-arid regions, seed quality of farmers’ retained seed might be compromised due to water stress experienced by maternal plants during production. The aim of this study was to determine the effect of water stress on maternal plants on subsequent seed quality of bambara groundnut. A single bambara groundnut landrace was characterised into four distinct selections based on seed coat and speckling colour. Initial seed quality (viability and vigour) was evaluated prior to planting seed in a field trial under irrigated and rainfed conditions. Final yield and yield components were determined at harvest. Thereafter, seed quality (viability and vigour) of progeny of different landrace selections was evaluated. Yield was lower under rainfed than irrigated conditions. Overall, subsequent seed quality showed improvement from initial seed quality of the original seedlot. Seed viability was higher in seeds produced under irrigated than rainfed conditions. Seed quality of bambara groundnut may be reduced underwater-limited production conditions. Seed enhancement practices such as priming may assist farmers to achieve better emergence. In the long term, seed production should be done under optimum conditions in order to achieve high-seed quality.

Climate Smart Agriculture (CSA) is crop and livestock production that sustainably increases productivity, resilience (adaptation), reduces/removes greenhouse gases (mitigation), and enhances achievement of national food security and development goals. CSA encourages the use of all available and applicable climate change solutions in a pragmatic and impact-focused manner. The Food Agriculture and Natural Resources Policy Analysis Network (FANRPAN) commissioned this scoping study on CSA with the overall objective of creating a policy environment that increase agricultural productivity and strengthen the resilience of vulnerable smallholder farmers to the impacts of climate change.

Amaranthus cruentus, Corchorus olitorius and Vigna unguiculata are traditional leafy vegetables with potential to improve nutritional security of vulnerable people. The promotion of these crops is partly hindered by the lack of agronomic information. The effect of plant spacing on growth, physiology and yield of these three leafy vegetables was evaluated under commercial-scale production at Roodeplaat, Pretoria over two summer seasons, 2011/12 and 2012/13. A randomised complete block design was used with plant density (100 000, 66 666 and 50 000 plants ha−1) as a factor. Chlorophyll content index (CCI), chlorophyll fluorescence, stomatal conductance, leaf number, leaf area index (LAI) and biomass were measured in situ. Planting at 100 000 plants ha−1 resulted in lower (P < 0.05) LAI, CCI and biomass per plant for A. cruentus and C. olitorius. Total yield of A. cruentus, C. olitorius andV. unguiculata was higher (P < 0.05) at 100 000 plants ha−1 relative to 50 000 and 66 666 plants ha−1. For A. cruentus and C. olitorius, higher leaf attributes (CCI, plant height, leaf number, biomass per plant and LAI) were obtained and this indicated that traditional leafy vegetables can be produced commercially under lower densities using a drip irrigation system. Using 66 666 plants ha−1 is suitable for commercial production of A. cruentus and C. olitorius, whereas 50 000 plants ha−1 may be recommended under low water availability. For V. unguiculata 100 000 plants ha−1 is recommended.

The project mainstreams the climate risk considerations in the Land Rehabilitation Programme of Lesotho for improved ecosystem resilience and reduced vulnerability of livelihoods to climate shocks.

Bambara groundnut (Vigna subterranea L.) is an underutilised African legume that fits the same ecological niche as Arachis hypogea. It is still cultivated using landraces and little is known about their seed quality. The current study evaluated seed quality characteristics (viability and vigour) of a local landrace on the basis of seed coat and speckling colour (plain red, plain cream, black speckles and brown speckles). Standard germination and electrolyte conductivity (EC) tests were used to evaluate viability and vigour. Seed imbibition rate was evaluated using two imbibition methods (seed-testing water bath and seed soaking). For each method, seeds were weighed at intervals and their water activity determined. Electron microscopy was used to determine seed coat thickness. There were highly significant differences (P < 0.001) among landrace selections with respect to germination, EC as well as imbibition and water activity. Black-speckled landraces had the highest germination (87%) and the plain cream landrace selections had the lowest final germination (67%). Brown-speckled and plain cream seeds had the highest (1 400 µs g-1) and lowest EC (36 µs g-1), respectively. Imbibition rate and water activity showed much fluctuation. Electron microscopy revealed that brown-speckled seeds had the thickest (116 µm) and plain cream seeds had the thinnest (107.9 µm) seed coats. The study concluded that seed quality in bambara groundnut was associated with seed coat and speckling colour.

Promotion of taro, a neglected underutilised crop, as a possible future crop under water-limited conditions hinges on availability of information describing its yield responses to water. Therefore, AquaCrop was calibrated and validated for the first time for an eddoe type taro landrace from South Africa, using data from pot, field and rain shelter experiments conducted over two seasons (2010/11 and 2011/12) at two locations (Pretoria and Pietermaritzburg) representative of semi-arid climates. Observed weather and soil physical parameters for specific sites together with measured crop parameters from optimum experiments conducted during 2010/11, were used to develop climate, soil and crop files in AquaCrop and to calibrate the model. Observations from the 2011/12 growing season and independent data were used to validate the model. Model calibration showed a good fit (R2 = 0.789; d-index = 0.920; RMSE = 2.380%) for canopy cover (CC) as well as good prediction for final biomass (RMSE = 1.350 t ha−1) and yield (RMSE = 1.205 t ha−1). Model validation showed good simulation for CC under irrigated conditions (R2 = 0.844; d-index = 0.998; RMSE = 1.852%). However, the model underestimated CC under rainfed (R2 = 0.018; d-index = 0.645; RMSE = 20.170%) conditions. The model predicted biomass (R2 = 0.898; d-index = 0.875; RMSE = 5.741 t ha−1) and yield (R2 = 0.964; d-index = 0.987; RMSE = 1.425 t ha−1) reasonably well for pooled data [field (RF and FI) and rain shelter (100, 60 and 30% ETa)]. The model also predicted biomass (R2 = 0.996; d-index = 0.986; RMSE = 1.745 t ha−1) and yield (R2 = 0.980; d-index = 0.991; RMSE = 1.266 t ha−1) well for the independent data set.

Taro [Colocasia esculenta (L.) Schott] is an underutilised crop in sub-Saharan Africa due to lack of agronomic research on it. There is no information describing water-use and drought tolerance of local taro landraces. Therefore, the objective of this study was to evaluate growth, yield and water-use of three South African landraces of taro under varying water regimes. Three taro landraces [Dumbe Lomfula (DL), KwaNgwanase (KW) and Umbumbulu (UM)] were planted in a rainshelter (14, October, 2010 and 8, September, 2011) at Roodeplaat, Pretoria, South Africa. Three levels of irrigation [30%, 60% and 100% crop water requirement (ETa)] were applied three times a week using drip irrigation. Emergence, plant height, leaf number, leaf area index (LAI) and stomatal conductance were measured in situ. Root length, fresh and dry mass were obtained by destructive sampling. Yield, yield components and water-use efficiency were determined at harvest. Taro landraces showed slow and uneven emergence. Stomatal conductance was respectively, 4% and 23% lower at 60% and 30% ETa relative to 100% ETa. Such a decline was clearer in the UM landrace, suggesting greater stomatal regulation in the UM landrace compared with KW and DL landraces. Plant growth parameters (plant height, leaf number and LAI) were shown to decrease by between 5% and 19% at 60% and 30% ETa, respectively, evapotranspiration relative to 100% ETa. The KW and DL landraces were shown to decrease the most while the UM landrace had moderate reductions in growth. Taro yield was 15% and 46% higher at optimum irrigation relative to 60% ETa and 30% ETa, respectively. Water-use efficiency was relatively unchanged (0.22–0.24 kg m−3) across varying water regimes. On average, the UM landrace had 113% higher WUE than the KW landrace. These findings can be used to differentiate the landraces on the basis of potential drought tolerance.

We, the African Member States and Parties to the United Nations Convention to Combat Desertification (UNCCD), Ministers, Heads of Delegation and Experts, attending the High Level Meeting of the first African Drought Conference (ADC);

Having met in Windhoek, Namibia from the 15 – 19 August 2016;

Congratulate the Government of Namibia and the UNCCD Secretariat for coordinating and organizing the first African Drought Conference, and thanking in particular NEPAD and all sponsors of the ADC.

Recognizing the alarming impacts of the recent 2015/2016 El Nino events as one of the most severe in recent decades
across Africa.

In Namibia, agriculture and forestry contributes 5.1% to the Gross Domestic Product (GDP) and livestock alone contributes 3.5% which is a contribution of 68.63 % to the Agricultural GDP (Namibia Statistical Agency’s, 2012).

In addition, agriculture plays a critical role in the formal and informal economy supporting 70% of the population directly or indirectly through employment and income generation (Ministry of Environment and Tourism, 2015).

Crop production activities in Namibia are limited, mainly due to the arid climate and low rainfall patterns. Small-scale farmers use traditional methods of production that are characterised by low productivity (Ministry of Foreign Afairs of Finland, 2015).

This weakens the food security of the population and the dependence on rain-fed agriculture increases the vulnerability of farming systems and predisposes rural households to food insecurity and poverty.

It is projected that the reduction in crop yields will have devastating impacts on food security at both national and household levels. Under the current conditions, the agriculture sector in Namibia needs to grow by 4% a year to meet the food requirements for the expanding population (Ministry of Foreign Afairs of Finland, 2015).

In light of these challenges, Namibia needs to adapt its agricultural practices and increase the resilience of livelihoods to be able to withstand the challenges posed by Climate Change to sustain development and growth of the country. This is why Climate Smart Agriculture (CSA) is an important topic for discussion at all levels of the society.