A critical assessment of the system of rice intensification (SRI)

The system of rice intensification (SRI) has been proposed as an integrated and agroecologically sound approach to rice (Oryza sativa L.) cultivation. It was mainly developed through participatory on-farm research conducted in Madagascar, but its evaluation is ongoing in Asia as well. This paper critically discusses some of the assumptions underlying the SRI and its scope for improving rice production in Asia. A review of cropping practices at known high-yield sites showed that techniques such as SRI are not necessary for growing rice near the yield potential. A move from permanent flooding to intermittent irrigation bears short- and long-term risks that are not well understood, but non-flooded conditions will generally favor rice growth on poor soils with potential for Fe toxicity. Deep root systems are associated with low input rice cropping and the intermittent water management practiced in SRI, but they are not a necessity for maximum rice performance, particularly in favorable environments with intensive cropping, short growth duration, and good water and nitrogen management. Approaches such as SRI may serve the important needs of resource-poor farmers in areas with poor soils, but are likely to have little potential for improving rice production in intensive irrigated systems on more favorable soils, where high yields can be achieved through implementation of more cost-efficient management practices. [Copyright &y& Elsevier]