A major advantage of SRI is that it gives low-income farm families a basket of benefits that enables them to improve their quality of life and economic status. SRI helps improve food security and requires less water and fewer seeds. It favours organic fertilisation, results in plants that are stronger, more resilient to extreme weather and more resistant to pests and disease. As a knowledge-based system, it also costs nothing to adopt.
In addition, and key factors in the work of SRI4Women, the impacts of SRI include improved health and nutrition, especially for women, diversified farms, improved incomes, a lighter workload for women and the preservation of rice biodiversity. The methodology also has important implications for adapting to and even mitigating climate change.
Improved Food Security
SRI produces higher yields, at least between 20% and 50%, and often yields of 100% or more. As this works with all kind of rice varieties, old and new, it allows farmers more options and profitable opportunities for the use of heirloom varieties, thereby preserving them and making greater biodiversity profitable. With higher yields from rice, farmers not only improve their food supply and income but they are often able to take some land out of rice and use it to grow higher value cash crops or diversify their production with fruits and vegetables, which improve nutrition. With more income from reduced production costs and/or income from selling rice families can also enhance their diets with higher quality foods, especially proteins.
SRI plants can thrive with 30-50% less water than is recommended and applied with conventional production methods, which keep rice plants constantly flooded. Water savings with SRI as much as 84% have been recorded (2).
With SRI management farmers use 70-90% fewer seeds. This can result in a major cost savings if they are purchasing seed in the market, and a major reduction in labour, as it takes less time to manage the fewer seeds, from sowing to transplanting. Also, since so many fewer seeds are required, this leaves more rice for the family to consume. These are significant benefits that have real impact on the lives of people who sometimes cannot grow enough food for the entire year and who struggle to earn enough to achieve even a basic standard of living.
Organic vs Chemical Fertilisation
While organic fertilisation gives better agronomic and economic results with the practice of SRI, it is not an essential requirement. Nonetheless, it is highly recommended to enrich the soil biota and produce the nutrients and soil conditions that plants need to thrive. Healthy soils are also more effective at retaining water. Over-use of synthetic fertilizers in agriculture is leading to degradation of soils and water quality worldwide, and runoff from fields can create dead zones in water bodies and devastate fish and aquatic life.
SRI plants have stronger root systems. The reduced competition among plants, together with the aerated and organic matter-enriched soils creates stronger plants above and below ground with larger, deeper root systems that can resist drought and extreme temperatures better. Also, increases in beneficial microbial activity and processes have been recorded in the SRI plant-soil environment, which are key for improved plant performance and productivity. Due to the deeper and larger root systems, SRI plants have greater resistance to damage from storms, being less likely to lodge (fall over) than conventionally grown rice. Lodging and storm damage can devastate a family’s food supply and income source.
Pest & Disease Resistance
Stronger and healthier rice plants are less susceptible to pest and disease attacks. Given the much lower plant density with SRI, less humidity builds up within the plant canopy as air can circulate more easily among the plants. This provides pest and diseases with a less favourable environment compared to densely-planted and continually-flooded conventional rice paddies (Karthikeyan et al. 2010; Kumar et al. 2007; Visalakshmi et al. 2014). This eliminates the need for costly pesticides, which can be harzardous to people and the environment. Many farmers implementing SRI have seen fish and frogs return to streams and canals after they stop using synthetic pesticides.
SRI practices require no purchased inputs or resources not readily available in communities. The knowledge is open source. Thus the method is easily shared farmer to farmer. Once farmers understand the principles behind SRI they can and have adapted it to many other crops, such as wheat, tef, sugarcane, mustard, potatoes, and millet.
Potential Challenges & Disadvantages
SRI is not without its challenges. Developed for irrigated environments, it has spread rapidly in rainfed areas where water control is not good and farmers tend to be poorer. Aerobic versus flooded conditions can also result in more weeds.
In conventional rice growing, part of the reason paddy fields are flooded is to suppress weeds. SRI’s aerobic-soil approach eliminates the use of excess water, which has positive implications for the environment and local ecosystems. However, aerobic soil conditions are good for weeds as well as rice plants. SRI cultivation thus requires more weed control, for which SRI farmers are encouraged to use a simple mechanical weeder. This further improves the aerobic properties of the soil and enhances both root growth and the life in the soil. But even simple weeders can be unaffordable for some families, which means more time doing manual weeding. For those who can or must employ labourers, this cost needs to be weighed against a potentially bigger harvest. For agricultural labourers, most often women, however, weeding can create remunerative employment.
When all the principles of SRI are applied, water is controlled and applied in small amounts so that paddy fields are sequentially flooded and drained throughout the growing cycle. Where fields are served by irrigation systems, alternate wetting and drying is easier to do, achieving significant savings in water usage, a very real advantage particularly in areas that find their water levels in the soil dropping. In rice-growing areas that do not have the advantage of irrigation systems, investments in infrastructure and organisation to provide smaller but reliable supplies of water will make SRI more feasible, but such investments become more economical as the value of water increases due to its scarcity and alternative uses. SRI methods have been adapted by several million farmers to rainfed cultivation, but with climate change, the arrival and quantity of rain are becoming increasingly unpredictable. The best protective action in any case is to grow rice plants with longer, deeper root systems, as promoted by SRI practices. Farmers have found that with the hardier SRI plants adaptation to climate change is less of a challenge.
Change is Difficult
SRI practices overturn generations of “how things were done,” which can lead to initial resistance to adoption. The idea that one can get a higher yield with less seed and water is also counter-intuitive for farmers. SRI also requires more carefully handling of seedlings and attention to where and how they are planted. This can require more time and focus in the beginning as people become accustomed to the process. More careful land preparation may also be required to ensure a more level field and more even distribution of water. If a push-weeder is not available manual removal of weeds may be require more labour than under flooded conditions, creating a disincentive for farmers who already do not have enough labour, or who can’t afford to pay for help. Generally, however, once people get used to the new planting technique families are able to manage the work without having to hire outside help. The negative side of this is that it can lead to less work for landless labourers.
SRI as an innovation comes at an opportune time as we must reconsider strategic directions and redirections for agriculture in our new century. By raising dramatically the productivity of land and water, so that more output can be produced with less of these inputs, SRI counters some basic constraints. Also, given recent and expected increases in energy costs, it is going to be difficult to sustain many so-called ‘modern’ technologies. (2)