How does the Adoption of Modern Variety increase Productivity and Income?: A Case of the Rice Sector in Tanzania
Although high yielding modern rice varieties (MVs) have been gradually disseminating over Sub-Saharan Africa, little is known on how the adoption of MVs influences agriculture productivity and household income. To fill this research gap, we analyze two kinds of data sets in Tanzania: a national representative cross section data and a two-year panel data of irrigated farmers in one district. The most important finding is strong complementary relationship between MVs and water control; high yield is achieved when MVs are grown with improved bund in paddy fields in irrigated area. We also find that the use of chemical fertilizer and the practice of transplanting in rows increase yield and income of both the adopters and non-adopters of MVs in the irrigated area. In rain-fed area, we observe limited impact of MVs. These findings suggest that introducing MVs as a package of technologies including other agronomic practices is effective in order to fully achieve their potential. In the long run, development of irrigation would be important to realize a rice Green Revolution in Sub-Saharan Africa.
On the transferability of the Asian rice green revolution to rainfed areas in sub-Saharan Africa: an assessment of technology intervention in Northern Ghana
This article investigates the impact of technical intervention on the adoption of a set of improved rice production technologies, as well as on productivity and profit for smallholders in rainfed lowland areas in Northern Ghana. The key finding is that productivity and profit are significantly enhanced when modern varieties (MVs) and chemical fertilizer are adopted, coupled with water control techniques. This is essentially the transfer of the Asian Green Revolution to sub-Saharan Africa. Such transfer, however, is not truly successful unless information about the use of MVs and fertilizer is directly disseminated by extension activities.
The Possibility of a Rice Green Revolution in Large-Scale Irrigation Schemes in Sub-Saharan Africa
This paper investigates the potential of and constraints to a rice Green Revolution in Sub-Saharan Africa's large-scale irrigation schemes, using data from Uganda, Mozambique, Burkina Faso, Mali, Niger, and Senegal. The authors find that adequate irrigation, chemical fertilizer, and labor inputs are the key to high productivity. Chemical fertilizer is expensive in Uganda and Mozambique and is barely used. This is aggravated when water access is limited because of the complementarities between fertilizer and irrigation. Meanwhile, in the schemes located in four countries in West Africa's Sahel region, where water access is generally good and institutional support for chemical fertilizer exists, rice farmers achieve attractive yields. Some countries' wage rate is high and thus mechanization could be one solution for this constraint. Improvement of credit access also facilitates the purchase of expensive fertilizer or the employment of hired labor.