Farmer Moghanraj Yadav inspects a field of SRI rice in Tamil Nadu. (Photo: Moghanraj Yadav/courtesy of Norman Uphoff)
When Indian farmer Sumant Kumar harvested a record-breaking yield of 22.4 metric tons of rice per hectare from his one acre plot, instead of his usual yield of 4 or 5 tons per hectare, it was an achievement that created international headlines in the popular press. [Tons per hectare is the international standard for reporting rice yields. A hectare of land is about 2.471 acres.]
For a large part of the world's population, rice is the most widely consumed staple food. So any increase in rice yields is a very big deal indeed.
A radical alternative to input-dependent agriculture
What made Kumar’s yields so notable, however, is that he achieved these results using less than half of the usual applications of nitrogen fertilizer, and only standard applications of phosphorous and potassium.
In fact, the yields reported by Kumar — and which are backed up by higher-than-average reported yields from farmers across the globe — are being attributed to the system of rice intensification (SRI), an interrelated set of farming principles that rely on fewer seeds, less water and a partial or complete shift from inorganic fertilizers to organic manures and compost.
Perhaps unsurprisingly, SRI has proven divisive. It has spread globally through a network of farmers, extension agents, researchers and NGOs who saw the potential for increasing yields without resorting to expensive inputs of fertilizers or machinery. Meanwhile elements of the agribusiness establishment, which has long been pushing improved crop varieties and increased mechanization as the primary path to progress, has been critical of a concept that did not fit neatly within the dominant paradigm.
SRI farmers level paddy soil to ensure that water is used as efficiently and sparingly as possible. (Photo: SRI-Rice)
The concept of SRI was crystallized in the 1980s in Madagascar when Henri de Laulanie, a priest and agronomist, assembled a set of recommendations based on cultivation practices he had developed with lowland rice farmers during the preceding two decades. These recommendations included carefully transplanting seedlings at much wider spacing than is typically practiced; an end to the practice of keeping rice paddies constantly flooded; a focus on both passive and active aeration of the soil; and the measured use of (preferably) organic manures and fertilizers.
Norman Uphoff, senior adviser to the SRI International Network and Resources Center (SRI-Rice), and former director of Cornell International Institute for Food, Agriculture and Development, is the person often credited with bringing Laulanie’s work to the attention of the wider world. But even he remembers being decidedly skeptical when he was told about the benefits of SRI:
“When I learned about SRI from the NGO Tefy Saina, I didn’t believe its report that with SRI methods, farmers could get yields of 10 or 15 tons per hectare, without buying new improved seeds and without applying chemical fertilizer or pesticides. I remember telling Tefy Saina that we should not talk or think in terms of 10 or 15 tons because nobody at Cornell would believe this; if we could just raise farmers’ low yields of 2 tons per hectare to 3 or 4 tons, I would be satisfied.”
Over time Uphoff realized that something remarkable really was happening in fields where SRI was being practiced, and he has since dedicated his career to figuring out what that “something” is. How could farmers raise their paddy yields from 2 tons to an average of 8 tons per hectare? Without utilizing new “improved” seeds, and without buying and applying chemical fertilizers? With less water? And without providing agrochemical crop protection?
Uphoff is the first to admit that we don’t yet fully know all the details, but as the peer-reviewed literature on SRI grows, a clearer picture is beginning to emerge:
“There is no secret and no magic with SRI. Its results are and must be explainable with solid and scientifically validated knowledge. From what we know so far, SRI management practices succeed in large part because they promote better growth and health of plant roots, and increase the abundance, diversity and activity of beneficial soil organisms.”
These benefits, Uphoff suggests, point to a fundamental rethink of our mechanistic approach to agriculture. Rather than increasing production by simply improving crop genomes, or applying more chemical fertilizer, we have to learn to think in terms of whole systems and the relationships they are part of. The added benefit of such a worldview, says Uphoff, is that it opens up the potential for making improvements at every level of the farming system, optimizing everything from plant varieties and support of soil organisms to the mechanical and cultural systems that we evolve to cultivate them.
Farmers prepare paddy plots for cultivation. (Photo: SRI-Rice)
SRI also, Uphoff says, has profound socioeconomic implications, creating opportunities for some of the world’s poorest farmers — farmers who have not benefited from the shift toward mechanization and increased chemical inputs during the latter half of the 20th century:
“The most intractable problems of poverty and food insecurity are in agricultural areas where households have access only to small amounts of low-fertility land. They do not have the cash income needed to purchase the kinds of inputs that were essential for the Green Revolution.”
Farmers as innovators
SRI farmers are not, however, simply passive recipients of expert knowledge. Unlike the development of industrial agriculture, which followed a “top-down” model for disseminating new methodologies from research institutions to farms, the growth of the SRI movement is notable for its heavy reliance on farmer knowledge and willingness to experiment as an integral part of the development process.
SRI farmers in Kenya compare rice phenotypes using SRI and conventional management practices. (Photo: Dr. Bancy Mati, Jomo Kenyatta University of Agriculture and Technology/courtesy of Norman Uphoff)
This farmer-focused model of innovation should not be mistaken for the notion — much touted in some sustainable agriculture circles — that farmer knowledge is the only knowledge that matters. Much like the growth in citizen science, or the rise of open source computing and research, SRI serves as a reminder that true innovation is rarely about any one entity, individual or institution, but rather the interrelationships and interactions between them. As agronomist Willem Stoop argues in a forthcoming issue of Farming Matters magazine, SRI demonstrates that traditional rice farming practices were far from optimal:
“... although built on farmers’ experiences, SRI also challenges the idea that the knowledge of farmers by itself can provide a foundation for further agricultural advances. The emergence of SRI shows that, for thousands of years, farmers have not been growing rice in the optimal way. SRI has come about through farmers’ willingness to experiment with different approaches in co-operation with researchers and the results show the benefits of such experimentation.”
Criticisms of SRI diminish
The established rice research institutions have been slow to accept SRI. Criticisms have ranged from its being considered too labor-intensive to the argument that the benefits have yet to be quantified and reported in rigorous terms in peer-reviewed studies. But as the body of academic research has grown, Uphoff says, the critics have gradually become less vocal:
“A number of critical articles were published in the mid-2000s, but the push-back against SRI has been diminishing as more and more agricultural scientists have taken an interest in SRI, particularly in China and India, documenting the effects of SRI management and the merits of its component practices. There are now almost 400 published scientific articles on SRI.”
SRI fields in Iraq. (Photo: SRI-Rice)
The future of SRI
Interest in SRI continues to grow, and with that interest comes increased attention and further experimentation and research. Having seen favorable results with rice, farmers are now developing SRI-inspired principles for the cultivation of a whole range of crops, including wheat, legumes, sugar cane and vegetables.
Farmers inspect a wheat crop grown using SWI (System of Wheat Intensification) management principles. (Photo: SRI-Rice)
Some farmers also see potential for technological innovation based specifically on SRI principles, further challenging the notion of SRI being necessarily labor-intensive. Pakistani farmer and philanthropist Asif Sharif has been working toward a mechanized version of SRI which involves the laser-leveling of fields, the building of permanent raised beds, and mechanized precision planting, weeding and fertilizing of rice plants. He is combining SRI with conservation (no-till) agriculture and with an effort to move production toward fully organic management. Early trials suggest a 70 percent reduction in water use over conventional methods, as well as yields of 12 tons per hectare. In a technical report in the journal Paddy and Water Environment, Sharif describes his best-of-both-worlds approach as “paradoxical agriculture,” embracing both natural principles and the potential for technological innovation:
“Paradoxical agriculture is not simply ‘natural agriculture’ because it accepts the use of improved modern varieties and utilizes the boon of mechanical farm power applied to soil, water and cropping system management. It recognizes that existing genetic potentials can be exploited more productively than at present, with lower economic cost, less negative environmental impacts, and with greater contribution to human and ecosystem health.”
As science learns more about the hidden worlds of microbiology, it makes sense for the direction of agricultural innovation to shift from focusing on plant genomes or on chemical and mechanical inputs in isolation to an understanding of plants, soils, soil life and the farmers who cultivate them not just as separate entities, but as interconnected and interdependent components of a complete, living ecosystem.
The rapid growth of SRI is one sign of the benefits that such a systems-based approach might bring. With climate change and population growth continuing to raise significant questions about the viability of mainstream agriculture, pursuing such innovation has never been more urgent.
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