The System of Rice Intensification, or SRI, is an agroecological approach that allows rice farmers to increase yields while at the same time decreasing inputs such as water, chemical fertilizers, herbicides and pesticides. The SRI methodology works largely with resources farmers have on hand, and can be applied with all local or improved varieties. While the SRI methodology was initially developed with irrigated rice, it has also been adapted to rainfed lowland and upland rice systems. Although the practices can change depending on the local conditions, the core principles of SRI under rainfed or irrigated systems remain the same. These four core principles of SRI can help farmers and technicians implement SRI, while at the same time adapting it to their local conditions:
When these principles are used together, they allow the rice plants to express their genetic potential much better than when planted with conventional rice production systems. As rice plants are less crowded with SRI, and established at a young age in soil enriched with organic matter, each plant develops more productive tillers and a much larger root systems. This allows the plants to have a greater tolerance to adverse weather (drought, strong winds, etc.) and disease/pest attacks, mature 1-2 weeks earlier than under conventional practices, and have larger panicles, with better grain filling and larger grains.
Because of these changes in how the individual plants grow, SRI can increase yields substantially (50% or more), while using only 5-15% as much seed as conventional practices, and up to 50% less water than irrigated rice production.