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.
The determinants of technology adoption: a case of the rice sector in Tanzania
Using an extensive household-level data set collected in Tanzania, this paper investigates the determinants of technology adoption in rice cultivation by focusing on the role of credit. We find that credit enhances fertilizer use and the adoption of labor-intensive agronomic practices such as transplanting in rows, for which monitoring of hired labor is easy. We also find that new technologies are adopted more widely in irrigated areas and small-scale farmers are not at a disadvantage. Based on these findings, we argue that with appropriate policies including credit, a rice Green Revolution can improve the productivity of small-scale farmers in Tanzania.
Variations in agronomic characteristics of irrigated rice varieties: Lessons from participatory trials in South Eastern Tanzania
The agronomic characteristics of thirteen improved rice varieties were compared with farmers' own varieties, in two villages of South-Eastern Tanzania. The aim was to provide farmers with new varieties and to try out the idea of shortening the process of releasing new varieties. The variation between the varieties could be reduced to three principal component axes (PCA) representing 83% of the original variation in the first village and 76% in the second village. These PCA correspond to structural plant characteristics, grain characteristics and yield. The differences in structural characteristics and grain characteristics were statistically significant, while this was not the case for the differences in yield. Nevertheless, farmers were quick at selecting varieties with many tillers and high grain qualities. If the conventional procedure for releasing varieties would have been followed, it is unlikely that breeders would have retained these varieties.Making varieties, or promising lines, available to farmers at an early stage not only shortens the release process but also ensures that farmers get varieties suiting their needs.