The value chain extension strategy of Sasakawa Africa Association focuses on improving the capacity of national agricultural extension systems and follows various thematic areas along the value chain to address key challenges accountable for low income households and poverty in Africa. Farmer learning platform is a model designed to increase crop productivity and encompasses demonstration plots where technological packages demonstrated significantly outperformed other technology plots in crop productivity and average profit margins. Enterprise-oriented production, postharvest and trading centers are value adding models designed to improve the effectiveness of extension and adoption of postharvest and agricultural processing technologies by producers. The use of the above along with necessary capacity building has facilitated the development of profitable business linkages of smallholder farmers with financial institutions and reliable market opportunities. The community association trader-trainer model is a market-oriented business approach applied in combination with other extension models. In 2018, 297 community-based commodity association trader-trainers were mobilized and capacitated to improve farmer group dynamics and developed collective input and output access and cluster aggregation centers at community level where various agricultural produces were mobilized and collectively aggregated, and valued at about 3.9 million USD. The supervised enterprise project model is an innovative agricultural extension model developed along with above models for capacity development of extension agents and transfer of technologies to smallholder farmers. Over 6000 supervised enterprise projects have been introduced into 27 universities in 12 African countries for training front-line extension officers and extension delivery to farming communities.
Sustainable intensification is a key component of agricultural development in Africa, urgently needed to wean the continent off foreign food supply and to limit agricultural farmland expansion. It is expected that a relatively small fraction of farmers will adopt fertilizer technology, as profits in current economic settings are relatively small while risks are considerable with varying prices and uncertain yield responses. Many smallholders depend on off-farm income and local markets for food supply. Structural adjustments are therefore needed to allow management of larger units of land by trained farmers willing to take this opportunity, while recognizing land right sensitivities. There are large opportunities for African commodity crops to improve food security, including cassava and East African highland banana that strongly respond to fertilizer with limited environmental risks under good management. This requires investments in better functioning markets, local fertilizer production facilities that can produce regional crop blends and cost-efficient distribution networks, providing balanced fertilizers for African farmers.
Phosphorus is a key nutrient element involved in energy transfer for cellular metabolism, respiration and photosynthesis and its supply at low levels can affect legume nodulation, N2 fixation, and C assimilation. A two-year field study was conducted in Ethiopia in 2012 and 2013 to evaluate the effects of P supply on growth, symbiotic N2 nutrition, grain yield and water-use efficiency of three groundnut genotypes. Supplying P to the genotypes significantly increased their shoot biomass, symbiotic performance, grain yield, and C accumulation. There was, however, no effect on shoot δ13C values in either year. Compared to the zero-P control, supplying 40 kg·ha−1 P markedly increased shoot biomass by 77% and 66% in 2012 and 2013, respectively. In both years, groundnut grain yields were much higher at 20 and 30 kg·ha−1 P. Phosphorus supply markedly reduced shoot δ15N values and increased the %Ndfa and amount of N-fixed, indicating the direct involvement of P in promoting N2 fixation in nodulated groundnut. The three genotypes differed significantly in δ15N, %Ndfa, N-fixed, grain yield, C concentration, and δ13C. The phosphorus × genotype interaction was also significant for shoot DM, N content, N-fixed and soil N uptake.
Africa has experienced increasing aridity and higher frequency of droughts due to climate change during the half past century with possible adverse effects on agricultural production, especially in dry areas with low rainfall. Under the auspices of the Africa Water Action Program between the Chinese Ministry of Science and Technology (MOST) and the United Nations Environment Program (UNEP), the Institute of Agricultural Environment and Resources, Shanxi Academy of Agricultural Sciences (SAAS-IAER) has worked closely with domestic and overseas partners on technology transfer in Morocco, Zambia, Egypt, Niger and Ethiopia from 2008 to 2013. A drought early warning system has been established and validated, and drought adaptation technologies have been trialed, modified, demonstrated and extended in African countries, and this shows great potential to increase crop production, water and fertilizer use efficiency and desert control in rainfed areas of Africa. The project has continued for six years and is a successful case of technology transfer and capacity building in Africa. The knowledge and experience gained will be useful to researchers, technicians, aid agencies and policy makers who work on agricultural technology transfer for in dry areas of Africa.
Africa in facing numerous challenges in the 21st century in feeding its rapidly increasing population. Land resources have become limited due to urbanization and industrialization. The existing agricultural land has been degraded and soil fertility has declined due to unsustainable farming practices. Despite of progress made in the past several decades, hunger and malnutrition in Africa still hinder health, human development and economic growth, which will become even worse in the future if proper measures are not taken. Sustainable intensification is the only solution to tackling both environmental sustainability including climate change and malnutrition, i.e., to produce more foods in terms of nutrients human body needs with less natural resources and carbon emissions. To achieve this vision, innovations in technologies, policies and institutions are essential. The Chinese experience in Agricultural Green Development (AGD) can be shared with Africans when the region is pursuing its sustainable intensification strategy.
Across the African continent efforts to intensify agriculture have been limited to specific commodities, locations or particular production schemes. The causes for the widespread failure to overcome low land and labor productivity while maintaining ecosystem services have often be analyzed but remain poorly understood. A social-ecological system approach may help to better understand the complex nature of ecological disadvantages, postcolonial structures, limited connect between producers and consumer markets, low off-farm livelihood opportunities, partial underpopulation and lacking experience with the concept of sustainable production as a major impediment for sustainable intensification of the agricultural sector. Nevertheless, recent success stories in agro-pastoral systems as well as urban vegetable and animal production and associated value chains in West Africa, and in intensive mixed-cropping systems of the Great Lakes Region show the potential of stakeholder-driven agricultural intensification. Proper interpretation of these cases may provide lessons for a more widespread eco-intensification of smallholder agriculture in sub-Saharan Africa.
Knowledge of evapotranspiration (ET) and energy partitioning is useful for optimizing water management, especially in areas where water is scarce. A study was undertaken in a furrow-irrigated vineyard (2015) and a drip-irrigated vineyard (2017) in an arid region of north-west China to compare vineyard ET and energy partitioning and their responses to soil water content (SWC) and leaf area index (LAI). ET and soil evaporation (E) and transpiration (T) were determined using eddy covariance, microlysimeters, and sap flow. Seasonal average E/ET, T/ET, crop coefficient (Kc), evaporation coefficient (Ke), and basal crop coefficient (Kcb) were 0.50, 0.50, 0.67, 0.35, and 0.29, respectively, in the furrow-irrigated vineyard and 0.42, 0.58, 0.57, 0.29, and 0.43 in the drip-irrigated vineyard. The seasonal average partitioning of net radiation (Rn) into the latent heat flux (LE), sensible heat flux (H) and soil heat flux (G) (LE/Rn, H/Rn, and G/Rn), evaporative fraction (EF) and Bowen ratio (β) were 0.57, 0.26, 0.17, 0.69 and 0.63, respectively, in the furrow-irrigated vineyard and 0.46, 0.36, 0.17, 0.57 and 0.97 in the drip-irrigated vineyard. The LE/Rn, H/Rn, EF, and β were linearly correlated with LAI. The E, Kc, Ke, E/ET, LE/Rn, LEs/Rn (ratio of LE by soil E to Rn), H/Rn, EF and β were closely correlated with topsoil SWC (10 cm depth). Responses of ET and energy partitioning to the LAI and SWC differed under the two irrigation methods. Drip irrigation reduced seasonal average E/ET and increased average T/ET. From the perspective of energy partitioning, seasonal average H/Rn increased whereas LE/Rn, especially LEs/Rn, decreased. Compared with furrow irrigation, drip irrigation decreased the proportion of unproductive water consumption thereby contributing to enhanced water use efficiency and accumulation of dry matter.