Improving farmers’ livelihood in rainfed rice-based lowlands of Asia

About one billion people depend on rainfed lowland rice grown on 46 million hectares in South and Southeast Asia. Farmers in these environments are among the poorest in Asia. Rainfed rice faces various biophysical stresses resulting in low and unstable yields, averaging about 2 t ha-1 versus 5 t ha-1 in irrigated systems. The most important abiotic constraints to production are frequent droughts, submergence, and unfavorable soil conditions. Our objectives are to present some important characteristics, changes, and developments in this system, and to assess possible consequences for natural resource management and impact-oriented research. Contrary to developments in irrigated systems, the successful introduction of modern rice varieties is rather recent in rainfed environments. Their main advantages are higher yields, better fertilizer response, lower disease susceptibility, and shorter duration. Further varietal improvement for abiotic stress tolerance can be expected as a result of an increased focus on breeding for stress tolerance, including the use of recently discovered major quantitative trait loci. These developments as well as socioeconomic and production technology changes offer considerable opportunities for intensification of rainfed systems. They can also contribute to reduced production risk and provide options for diversification. But, to reach these goals, the variety-driven changes must be accompanied by improved and adapted crop and natural resource management options. Only integrated germplasm-crop management solutions adapted to the production environment can achieve stable production increases and maintain the sustainability of rainfed lowlands. We conclude that rainfed lowlands offer substantial potential for increased productivity. This would not only improve farmers’ livelihood, but could also contribute an important share to the rice production increases needed in the near future to compensate for high population growth rates and the loss of prime farmland.

SM Haefele, G Atlin, SP Kam, DE Johnson