Compatibility between Conservation Agriculture and the System of Rice Intensification

Conservation Agriculture (CA) and the System of Rice Intensification (SRI) are both agroecologically-oriented production systems that support more productive, sustainable, and resource-conserving farming, with synergies arising from their respective assemblages of reinforcing agronomic methods. This review article examines the compatibility between CA and SRI, considering examples of their being utilized in complementary ways. The application of CA principles enhances the growth, yield, and performance of the crops grown under the cropping system as well as the health and resilience of the whole ecosystem. SRI practices create more favorable conditions for the development of crop plants below- and above-ground, including conditions that can be enhanced by CA management. SRI practices such as reduced plant density m-2 can elicit a better phenotypic expression of the genetic potentials of crops grown with CA. For these two agronomic systems to converge at the field level, some of their respective practices for plant, soil, water, and nutrient management need to be modified or aligned. One such adaptation is to practice SRI in CA systems on permanent, no-till, mulch-covered raised beds, with rainfall or irrigation water in the furrows between the beds furnishing and controlling water and providing weed suppression and improved nutrient recycling. SRI rice cropping can benefit from the CA practices of no-tillage, mulch soil cover, and diversified cropping, both in paddies and on raised beds. Several examples have shown that this convergence of cropping systems is feasible for smallholding farmers as well as for larger-scale producers and also that SRI practices within a CA system are amenable to considerable mechanization. Further research and experimentation are needed to identify and assess appropriate practices for capitalizing upon their synergies.