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.
Yield and Income Effects of the Green Super Rice (GSR) Varieties: Evidence from a Fixed-Effects Model in the Philippines
With the increasing frequency of extreme climatic events, the new challenge is to develop rice varieties that are tolerant of drought, water submergence, and salinity. There are now new high yielding GSR cultivars developed at the International Rice Research Institute (IRRI) with increased tolerance of multiple abiotic stresses, such as drought, submergence, and salinity. But a clear understanding of the economic benefits of these varieties under farmers’ production environments is not yet fully understood. In this paper we assess the yield and income effects of GSR rice varieties using a two-year panel data from one province. We use the survey data and a fixed-effects model within a difference-in-difference (DID) framework to estimate the yield effects. The income effects were evaluated with a profit function using the parameter estimates from the yield/production function model. The results of the OLS and DID fixed-effects regressions both reveal significant and positive effects of GSR varieties on yield. The most important finding is that the benefits from these varieties are more strongly felt when there is flooding, which traditional varieties cannot withstand because of sensitivity to submergence. We also find that farmers who achieved higher yield through the use of GSR rice varieties in the presence of abiotic stresses, also obtained higher net farm income per hectare. These findings have very important implications for food security in the Philippines. With the dramatic climatic shifts, particularly in areas where rice production is dominant and extensive, the benefits that the GSR varieties could offer may be significant to secure more rice and alleviate poverty in the country.
The British Museum (Natural History) — University of London Joint Palæontological Expedition to Northern Rhodesia and Tanganyika, 1963
The British Museum (Natural History) — University of London Joint Palaeontological Expedition to Northern Rhodesia and Tanganyika, 1963