Rapid expansion of groundwater use for irrigation for dry season rice production in Bangladesh has led to overuse, deterioration of groundwater quality, increased cost of irrigation, and higher greenhouse gas emissions. The divergence between marginal private and social cost of irrigation due to market failures in the presence of these externalities, has resulted in excessive use of groundwater. A combination of policy reforms and improvements in irrigation practices are hence needed to reduce irrigation water use. The paper analyses why an improved irrigation practice, known as “alternate wetting and drying (AWD)” that can potentially reduce irrigation water use substantially, has failed to scale despite widespread testing and promotion in Bangladesh for over a decade. The main reason for this failure to scale is the lack of economic incentives to save water as pricing is based on per unit area irrigated, not on the amount of water used. This paper highlights the dynamics of the water market and pricing in Bangladesh, along with biophysical and social constraints to farmer adoption of AWD. It also proposes changes in policy incentives, new directions for crop and water management research, and institutional reforms for wider adoption of AWD and other water-saving practices.

Higher-yielding rice varieties adapted to the upland conditions of Yunnan were developed and disseminated during the late 1990s. Using cross-sectional farm-level data of 448 households collected from five prefectures in Southern Yunnan, this paper carries out an econometric analysis of the determinants of variations in the adoption of improved varieties among households and assesses the impact of adoption on rice income and total household income. The two major determinants of adoption were found to be the government programs for extension of improved upland rice varieties and for terracing of sloping fields. The presence of government programs for extension and for terracing contributed to increased adoption of improved varieties. Household-specific factors such as land and labor endowments were less important as these variables had a statistically insignificant impact on adoption. The adoption of improved rice varieties increased both rice income and the average household income. About half of the household income difference observed between the full adopters and non-adopters of improved rice varieties with comparable household characteristics can be attributed directly to the adoption. The results imply that increased investments in promoting improved rice varieties and terracing will generate additional income growth in the uplands of Yunnan.