The purpose of this study is to design the strategy to transform agriculture in SSA by means of generation and diffusion of modern agricultural technology. Following new statistical evidence and a critical review of the empirical literature, the study also attempts to identify the promising crops, required technologies to realize major productivity gains, and desirable government policies.
In this the paper, the fundamental source of agricultural transformation is technological change or innovation, which accompanies the introduction of modern agricultural technology and improved cultivation practices in the context of developing countries, such as countries in sub-Saharan Africa (SSA). Usually markets fail to generate and disseminate modern agricultural technology in a socially optimum manner because technological knowledge is often a public good. Thus, appropriate government intervention is necessary to achieve desirable technological change in agriculture.
According to the paper, while there can be many possible explanations for the failure to realize a Green Revolution in SSA, the following three are potentially most important:
- Lack of superior variety: Available improved variety is not sufficiently fertilizer-responsive and high-yielding, so that most farmers are largely indifferent between improved and traditional varieties. Furthermore, the demand for fertilizer is inexistent or small, as the marginal product of fertilizer is low.
- Ignorance about improved management practices: While improved rice production requires not only improved high-yielding varieties and ample application of chemical fertilizer but also the adoption of improved agronomic practices, such as bunding, leveling, and straight-row planting (Otsuka and Larson 2016), improved maize and other upland crop production requires rotation of crops including leguminous crops with capacity to fix nitrogen and application of manure, compost, and crop residues as well as improved variety and modern inputs (Kajisa and Palanichamy 2013; Otsuka and Muraoka 2015). The yield function shifts upward with the introduction of the improved management practices, as is illustrated by the upper curve in Figure 1. Since marginal product of modern input is high, its application will also increase, e.g., from point A or B to point C.
- Exorbitant prices of fertilizer and other modern inputs and low product prices: Prices of chemical fertilizer and other chemical inputs are much higher than the value of marginal product of fertilizer, particularly when traditional variety is adopted, so that it is perfectly rational for farmers not to apply any fertilizer. Even if farmers know that crop production can be increased by increased fertilizer application, they do not want to do so because the product market is so underdeveloped that the product price is low and increased outputs cannot be easily sold (Matsumoto and Yamano 2011).
The paper argues that to identify which crops are promising to realize a Green Revolution in SSA, it will be instructive to (1) confirm the extent to which the Green Revolution has taken place in the production of various grains in tropical Asia (focus on India in this paper), (2) measure the yield gap per hectare between tropical Asia and SSA, and (3) inquire if the Green Revolution has already taken place in the advanced regions in SSA, including South Africa. If Green Revolution did not take place in the production of certain crops in Asia, which is endowed with much better infrastructure and research and extension systems and more favorable policy environments than in SSA, it is probably difficult to realize a Green Revolution in such crops. Furthermore, if we do not observe significant yield gap between the two continents, the opportunity for technology transfer from Asia to SSA will be limited. If Green Revolution already took place in some crops in some advanced regions in SSA, such crops are likely to be promising. In this case, there is a possibility of scaling up Green Revolution by inter-regional technology transfer within SSA. Similarly, to the extent that South Africa is technologically advanced, we should consider technology transfer from this country to the rest of countries in SSA.
This paper examined the yields of five major grains; paddy rice, maize, wheat, millet, and sorghum. Except for wheat, these crops are grown mainly by smallholders, in which the inverse relationship between crop yield and farm size is observed, indicating that smallholders are not inefficient producers (Larson et al. 2014; Njagi et al. 2016; Sheahan and Barrett 2014). To represent tropical Asia, the paper uses India, as its climate is not far different from SSA (Tsusaka and Otsuka 2013). In fact, millet and sorghum, which are widely grown in SSA, are grown primarily in India in tropical Asia. To represent advanced regions in SSA, the top 10 countries in terms of average yield for each crop from 1961 to 2012, as well as South Africa selected. Apart from grains, the paper also contains a short discussion of high-value crops within the context of contract farming.
After analysis of data from the crops above, the paper concluded that rice was a promising crop for a Green Revolution in SSA. Unfortunately judging from the relatively stagnant yield, realizing a maize Green Revolution in SSA may look a daunting task, even though transfer of technology from South Africa is an option. Interestingly, unlike rice and maize, cultivators of wheat are not smallholders but large-scale farmers. Yet, there is no question that wheat Green Revolution has taken place in many parts of SSA, if we follow the definition of Green Revolution as the adoption of semi-dwarf varieties coupled with the increased application of chemical fertilizer. Limitation of wheat in SSA is that it is primarily grown in highlands endowed with cool climate, which are not abundant.
The paper notes that Green Revolution in millet and sorghum did not take place in India, as evidenced by slow yield growth and low yield level as of now. It seems that it is scientifically difficult to develop high-yielding varieties of these crops even in India. Another important observation is that the average yield of these crops in SSA is comparable to, and the average of top 10 countries is even higher than the yield in India, which indicates that there is not much room for transfer of technology from India to SSA. Yet, as far as sorghum is concerned, the yield in South Africa is distinctively high, so that some of its technology may be transferred to other countries in SSA. The tentative conclusion is that major research efforts are required to develop yield-enhancing technologies for these crops particularly suitable for agro-climate in many regions in SSA.
Theodore W. Schultz (1964) noted, just on the eve of the Green Revolution in Asia, that “farmers are efficient but poor,” because of the lack of technological change or innovation to use a preferred term. While the paper believes that Schultz’ thesis is valid in SSA, it argues that “appropriate innovations” are different for different crops and, hence, they need to be identified before designing effective strategy to transform African agriculture. For this purpose, it is useful to distinguish among new technology (e.g., new high-yielding varieties), improved management practices, and improved marketing (e.g., branding, establishment of reputation of high-quality producers, and direct sales from farmers or farmers’ groups to retailers and consumers). In identifying the critically important innovation, it is important to recognize that the three types of innovations are complementary: the productivity impact of new variety is limited without proper management (as is illustrated by Figure 1 in the paper and reproduced below), whereas marketing becomes more important when both the demand for modern inputs and supply of outputs increase owing to the improvements in technology and management practices. This implies that productive technology and improved management practices must be developed first, which should be followed by extension activities and improvements in marketing.
According to this paper, with the use of improved high-yielding seed varieties, correct application of fertilizer, and improved management practices (such as bunding), and farmer education rice yields in Africa can approach those of Asia. The paper therefore argues for investment in capacity building for the extension of modern rice technology and management practices to realize the rice green revolution. The paper argues, the rice green revolution could then provide a model that could be refined to promote green revolutions in other crops. Regarding maize, along with rice two of the most important food staples, the paper identifies a promising intensive intercropping farming system involving maize, legumes, and dairy on smallholder farms in Kenya, but proposes more research to refine and optimize it before promoting it through extension. Regarding high-value products in the context of contract farming, the paper identifies the real issues as neither technological nor managerial, as the contractor seems to know improved technology, management practices, and useful inputs. In order to expand contract farming, it seems best to reduce transaction costs in contracting between contractors and farmers. For this purpose, it is likely that improvement of entrepreneurial human capital of farmers is critically important. In reiterated the observation by Schultz (1975) that, “poor small farmers cannot move out of poverty, unless they acquire the ability to deal with disequilibria or to make appropriate production, marketing, and technology decisions in a dynamic setting”. Promoting the acquisition of such ability by farmers ought to be the fundamental strategy to expand the production of high-value products by smallholders in SSA.
 South Africa is not included in the top 10 countries.