RESPONSES TO FREQUENTLY - ASKED QUESTIONS

ABOUT THE SYSTEM OF RICE INTENSIFICATION (SRI)

Norman Uphoff, CIIFAD, ntu1@cornell.edu

Visit us at http://ciifad.cornell.edu/sri/

 

1. What is SRI?

 

The System of Rice Intensification (SRI) was developed as a set of insights and practices that change the management of plants, soil, water and nutrients used in growing irrigated rice. These concepts and practices can be adapted for growing rice that is unirrigated or rainfed as well as other crops. SRI methods, by promoting growth of more productive and robust plants:

  • Give higher yield -- more tons of rice per hectare or per acre,
  • Require less seed and less water  -- because plant populations are reduced, and paddy fields are not kept continuously flooded,
  • Do not require purchase of external inputs  - - since chemical fertilizer or agrochemical protection are not necessary, although they can be used with the other practices, and
  • Do not require the purchase of new seeds  - - since practically all rice varieties give higher yield with these methods, though some high-yielding varieties respond better than others.

SRI methods are particularly accessible to and beneficial for the poor, who need to get the maximum benefit from their limited land, labor, water and capital. However, SRI concepts and practices can be adapted and used with any scale of production, from small-scale to large-scale. In an unprecedented way, SRI methods raise the productivity of land, of labor, of water and of capital all at the same time. SRI’s higher productivity is making more rice available, with prospectively lower prices and with widely distributed benefits. 

 

Basically, the management practices that are recommended in the name of SRI promote:

  • The growth and health of rice plant roots -- so that they grow larger and deeper, not degenerating for lack of oxygen in the soil, and

  • The abundance, diversity and activity of soil organisms -- bacteria, fungi, earthworms and other soil biota -- that improve soil fertility and contribute to plant growth and health

In practice, SRI involves some combination of the following changes in rice cultivation practices. These practices are summarized here and then elaborated below, being explained in response to Question # 6:

 

  • Transplant seedlings at a very young age – 8 to 12 days old, at most 15 days old, instead of the usual age for seedlings of 3-4 weeks or more.

  • Raise seedlings in unflooded nurseries, not planted densely and well-supplied with organic matter. There is an option of direct-seeding, but transplanting is most common.

  • Transplant seedlings quickly, carefully and shallow : taking care to have minimum trauma to roots, not inverting plant root tips upward which delays resumption of growth.

  • Transplant seedlings at wider distance and singly -- rather than in clumps of 3-4 plants  -- and in a square pattern, usually 25x25 cm, giving roots and leaves more space to grow.

  • Do not continuously flood the soil : soil saturation causes plant roots to degenerate and suppresses soil organisms that require oxygen; either apply small amounts of water daily, to keep soil moist but not saturated, or alternately flood and dry the soil.

  • Weed control is preferably done with a simple mechanical hand weeder. This aerates the soil as it eliminates weeds, giving better results than either hand weeding or herbicides.

  • Provide as much organic matter as possible to the soil – while chemical fertilizer gives positive results with SRI practices, the best yields will come with organic fertilization. This does more than feed the plant: it feeds the soil, so that the soil can feed the plant.

ELABORATION:

SRI methods were assembled about 25 years ago, as explained below. However, they only began to receive attention around the world after 2000.  SRI methods have been validated in 30 countries across a wide range of agroecosystems -- from the equator to temperate climates, and from sea level to 2700 meters above sea level. The number of countries where SRI has been proven and where it is expanding continues to increase. Countries recently ‘joining the SRI club’ include Bhutan, Brazil, Iran, Iraq, Afghanistan and Zambia. The greatest spread of SRI is in the Indian state of Tamil Nadu, where two years ago, the area under SRI was about 40,000 hectares (100,000 acres). In the 2007/08 season, according to the Minister of Agriculture, the rice area cultivated with SRI methods reached 430,000 hectares, i.e., over 1 million acres.

See article in the Indian national newspaper   The Hindu, 1/1/08  (http://www.thehindu.com/2008/01/01/stories/2008010153180300.htm)

  • SRI is considered as a methodology rather than as a technology since it consists of concepts and practices to be adapted by farmers to their local conditions for best results. SRI is not a fixed set of things that farmers ‘must’ do. Using SRI methods requires no material inputs beyond what farmers already have, just a change in thinking and practice.

    • Although SRI is commonly referred to as a thing (a noun), the term is better used as a description (an adjective). SRI refers to the use of specific practices that reflect key insights and principles for providing an optimum growing environment for rice plants.

    • All plants, indeed all organisms, are phenotypes. That is, they are the outcomes of interactive processes in which an initial genetic potential (genotype) through interaction with its environment produces a unique creature, or phenomenon (phenotype). This explains why even identical twins are never identical persons and personalities.

    • By altering plants’ environments, SRI practices create more productive phenotypes from any rice genotype, i.e., from any genetic potential. There is no magic in SRI. All of the effects of its practices can be explained in well-established scientific terms, often in terms of very simple and elementary relationships, like not crowding plants together.

    • Because some varieties (genotypes) respond to SRI practices better than others, it is clear that genetic potentials are important. As discussed below, many ‘traditional’ or ‘unimproved’ varieties give good responses to SRI methods and can be more profitable for farmers to grow because, being preferred by consumers, their market prices are higher. Thus ‘improved’ varieties are not necessary for productive and profitable rice cultivation.

    • Because SRI results depend on the unfolding of biological processes and potentials, the results with SRI can be quite variable, more variable than if results are due to a fixed genetic ‘blueprint’ -- or if outputs are primarily due to and thus proportional to external inputs such as agrochemicals. This variability is disconcerting to some persons, but it is this ‘plasticity’ that offers great opportunities to farmers who, through better management, can learn to capitalize on these potentials.

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1.1.  What are the Key Practices?

 

SRI is most easily visualized in terms of certain practices that are recommended to farmers for trying out on their own rice fields to improve the productivity of their rice crop. These practices are based upon important insights and principles that constitute SRI. The practices discussed below which are recommended for SRI are in effect the ‘signature’ of SRI.

 

SRI recommendations change what are often age-old methods for growing irrigated rice. This means that even though the practices are simple, they may not be readily adopted. It is important always to emphasize the reasons for making changes in practice: to promote bigger, healthier root systems that support larger, more productive plants that grow in more fertile soil systems.

  • When establishing a rice crop by transplanting, use very young seedlings -- less than 15 days old, and preferably 8-12 days old in tropical climates. The usual age of seedlings used now is 3-4 weeks, and up to 6-7 weeks in some places. Seedlings older than about 15 days lose much of their potential for profuse growth of roots and tillers (stalks).

    • Note that in colder climates, somewhat older seedlings, even up to 20 days, can be the physiological equivalent of ‘young seedlings’ because their grown will be slower.

    • Note further that farmers in several countries are experimenting successfully with direct seeding. This saves them labor. SRI will probably evolve in this direction; but for now, SRI focuses on reduction in seedlings’ age when transplanting, a familiar practice.

  • Seedlings for transplanting should be grown in an unflooded, garden-like nursery, watered by watering can, with a fairly low seeding rate, so that seedling roots have plenty of room to grow. Soil used should be very loose and rich in organic matter, for easy removal.

  • When taking seedlings out of the nursery, they should be removed very carefully, lifted with a trowel (unless being grown on trays for easy transport to the field). This will keep the seed sac attached to the root. Dirt should not be knocked off from the roots. Seedlings should be transplanted quickly after being removed from the nursery so that their roots do not dry out, and they should be transplanted in the soil very shallow, just 1-2 cm deep.

    • Seedlings should not be pushed down vertically into the soil. This inverts their root tips upward. This will delay resumption of growth after transplanting. Root tips that are inverted take a week or more to reorient themselves downward and start growing again

  • Seedlings should be transplanted into the field with wider spacing than usual: (a) putting single seedlings in each hill, instead of 3-6 plants together in a clump as is usually done, and (b) in a square pattern, 25x25 cm or even wider if or when soil fertility is very good due to biological activity. Square-pattern/grid planting permits weeding in perpendicular directions.

  • Paddy fields should not be kept continuously flooded as this creates oxygen-less (hypoxic) soil conditions that inhibit root growth and prevent the flourishing of aerobic soil organisms, ones that require oxygen. Small amounts of water should be applied daily to keep the soil moist but not saturated; or fields can be alternatively flooded and dried, which requires less work. Both serve the same purpose: keeping the soil moist but aerobic, i.e., oxygenated.

  • Whenever paddy soils are not kept flooded, weed growth becomes a greater problem. Weeds can be removed by hand or with herbicides, but for best SRI results, we recommend use of a simple mechanical weeding implement -- a rotating hoe or conoweeder -- starting 10-12 days after transplanting. Additional weedings are done every 10-12 days until rice plant growth inhibits further weeds. Active soil aeration enhances plant performance in many ways.

  • SRI was initially developed with use of chemical fertilizers to enhance soil nutrient supplies. But this requires a cash outlay from the farmer, and plant performance is even better with organic fertilization. We recommend application of compost of decomposed biomass, made from rice straw, weeds, crop residues, loppings from shrubs and trees, kitchen wastes, any available animal manure. Such organic matter is valuable not so only for its nutrient content but for what it can do to stimulate the growth and services of soil organisms. These services include improved soil structure, nutrient cycling, nitrogen fixation, phosphorus solubilization, better water absorption and retention, induced systemic resistance to soil pathogens, etc.

These practices are mutually reinforcing. They nurture the growth of roots and canopies (leaves and tillers), and they reinforce each other through better nutrient acquisition and photosynthesis.

 

There are a number of other practices that are beneficial when used together with any cultivation methods and thus complement SRI practices, including:

 

  • Land preparation:  Soil should be well worked and well-leveled so that there is good soil structure, and plant roots can grow easily. Correct leveling helps farmers to achieve uniform wetting of their soil through irrigation with a minimum application of water.

  • Varietal selection: Choose a variety, improved or traditional, that is well-suited to local conditions (soil, climate, drainage, etc.), being resistant to anticipated problems like pests or irregular water supply, and having desired grain characteristics.

  • Seed selection: Only the best seed, with good density and formation, should be used. Submerging the seed in a pail of water, with enough salt dissolved in it to make a salt solution in which an egg will float, enables farmers to separate and discard any light and inferior seeds as these will float. Just use the good seeds that sink to the pail’s bottom.

  • Seed priming: This practice of soaking seed before planting has been found to enhance the rate of germination and seedling emergence. Details on seed priming can be obtained on the web at:  http://www.gaia-movement.org/files/Booklet%2029%20Priming.pdf / http://www.decagon.com/literature/app_notes/SeedPriming.pdf

  • Nursery solarization: Where there are soil health problems, such as fungal pathogens or root-feeding nematodes, it will be beneficial to cover the nursery for seedlings for 2-8 weeks before sowing with clear plastic in order to raise the soil temperature by as much as 10oC. This can eliminate many organisms that have adverse impacts on young seedlings. It will enable the nursery to produce seedlings with greater health and vigor and this will improve subsequent crop performance (Banu et al., 2005).

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1.2.  Why is SRI Not Presented as a NEW TECHNOLOGY?

 

We refer to SRI as a system or as a methodology, a system of practices based on a coherent set of concepts and principles that produce desired results. Why not call SRI a ‘technology’? This term implies something that is fixed and final, something to be used as instructed -- rather than as something still evolving and improving, season by season, as more experience is gained and as more farmers, scientists and others apply their intelligence and insights to making rice production more efficient and sustainable. Indeed, Some Indian colleagues have suggested the SRI stand for ‘System of Rice Improvement.” SRI, we like to reiterate, is a work in progress.

 

When SRI is presented not as a technology, i.e., as something to be adopted, but instead as an innovation -- based on new thinking about how to provide rice plants with an optimal growing environment – this presents SRI as something they can and should contribute to. Further, it makes explicit that farmers are expected to make their own adaptations to their local conditions. It is expected also that they can make improvements in the system. Thus, farmers are encouraged to engage in participatory technology development, in contribute to a process of technological development, as active partners rather than as docile adopters.

 

Also, technology in most people’s minds is associated with something material – a new implement, a better seed, a specific fertilizer -- whereas SRI is something entirely in the mind. The name of the NGO which has given leadership to SRI development and promotion in Madagascar -- Association Tefy Saina -- means ‘to improve the mind.’ That there are no material requirements for practicing SRI puts it in a very different category from the kinds of technologies that currently dominate in the agricultural sector. This means that SRI’s benefits can be achieved simply by changing thinking and practice, not by buying things and using them.

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2.  Where Does SRI Come From?

 

SRI was developed in Madagascar through the efforts of Fr. Henri de Laulaniè, S.J., who spent 34 years of his life working with poor farmers there, to help them reduce their poverty and hunger by improving their production of rice, the source of more than half of Malagasies’ calories. He sought to rely on simple methods that would not require purchase of external inputs.

 

Laulaniè was born in France in 1920 and attended its leading agricultural college before World War II, at which time he decided to change careers and entered a Jesuit seminary in 1941. Upon graduation in 1945, he worked in France until 1961, when he was sent by the Jesuit order to Madagascar as an agricultural missionary. Although he knew little about rice, he understood a lot about agriculture in general and decided to focus on this crop.

 

Over the next two decades, he observed and experimented with various practices. Some SRI practices he learned from farmers who had departed from traditional cultivation methods. A few transplanted single seedlings instead of clumps of 3-6 seedlings, and some others did not keep rice fields continuously flooded, only moist enough to meet crop needs. Fr. Laulanié himself adopted the use of a rotating hoe that aerates the topsoil at the same time it eliminates weeds. (These can become a big problem when farmers do not keep their rice fields always flooded.)  He also introduced planting in a square pattern, 25x25cm, i.e., 10x10 inches, reducing plant populations by 80-90%. This radical change gives plants ample room for roots and above-ground parts to grow as they are better exposed to sunlight and air. Planting in a square pattern created opportunity for doing mechanical ‘weeding’ in perpendicular directions, enhancing soil aeration and plant growth, while at the same time reducing pest and disease problems.

 

The biggest single step toward the development of SRI was the accidental discovery in 1983-84 that transplanting very young seedlings, just 15 days after seeds had been sown in the nursery, could greatly enhance yield (Laulaniè, 1993). By using young seedlings, the plants’ potential for prolific growth of roots and tillers is preserved, as explained by understanding phyllochrons, discussed in FAQ #17. SRI was developed using chemical fertilizer, but when the government removed its fertilizer subsidy in the late 1980s, and small farmers could no longer afford it, Laulaniè modified SRI to utilize compost, which proved even more beneficial for plant growth.

 

In 1990, together with several close Malagasy friends and colleagues, Laulaniè formed a small NGO called Association TEFY SAINA. This Malagasy words ‘improve the mind,’ rather than ‘grow more rice.’ Association Tefy Saina has sought to promote broad-based agricultural and rural development in Madagascar (Laulaniè, 2003). In 1994, Tefy Saina began working with the Cornell International Institute for Food, Agriculture and Development (CIIFAD) on an integrated conservation and development project funded by USAID in and around Ranomafana National Park to protect rainforest ecosystems of the country’s central-eastern escarpment.

 

Over the next three cropping seasons, farmers trained by Tefy Saina field staff achieved average yields of 8 tons/hectare, where previously they had averaged only 2 tons/hectare. Some reached yields of 10, 12, even 14 tons. In 1997, CIIFAD began trying to get colleagues in other countries to try SRI methods for themselves. Sadly, Fr. de Laulaniè had died by this time, in June 1995 at age 75. It fell to Tefy Saina and CIIFAD to carry on his work, building on his insights and trying to share more widely the opportunities that his lifetime of selfless, innovative work had created.

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2.1. How Has SRI Spread Around the World?

 

Before drawing any conclusions about SRI’s efficacy, CIIFAD waited for three years of results, until 1997, following normal practice for agricultural science. It then took two years to get others outside Madagascar to take an interest in SRI -- because SRI seemed ‘too good to be true.’

 

In 1999-2000, researchers at Nanjing Agricultural University in China and at the Ministry of Agriculture’s Agency for Agricultural Research and Development (AARD) in Indonesia tried SRI methods. Their results, along with those of the China National Rice Research Institute, verified that more productive phenotypes of rice could be produced by using these alter-native methods (Wang et al., 2002; Gani et al., 2002; Zhu et al., 2002; Tao et al., 2002). The scientist known as ‘the father of hybrid rice,’ Prof. Yuan Longping, director of China National Hybrid Rice Research and Development Center, also validated SRI methods (Yuan, 2002).

 

In June 1999, the secretary of Tefy Saina, Justin Rabenandrasana, made a presentation on SRI to an NGO conference on rice in the Philippines. The editors of LEISA  magazine invited Justin to prepare an article on SRI for its worldwide readership, especially among NGOs (Rabenandrasana, 1999). (LEISA stands for ‘low external-input sustainable agriculture.’) In April 1999, Norman Uphoff, director of CIIFAD, presented a paper on SRI at a conference on agroecological alternatives held at the Rockefeller Foundation’s center in Bellagio, Italy, further publicizing the new methods (Uphoff, 1999), having made a presentation on SRI to the International Rice Research Institute (IRRI) at Los Baños the previous month. In October 2000, the president of Tefy Saina, Sebastien Rafaralahy, made a presentation on SRI to a symposium on sustainable agriculture in Baltimore MD, organized by the World Bank in conjunction with the Agronomy Society of America meetings that year. In January 2001, ECHO Development Notes published an article on SRI that further spread knowledge of the new system (Berkelaar, 2001) at the same time that Rafaralahy made a presentation on SRI at an international conference on sustainable agriculture convened at St. James’ Palace in London.

 

From these forums and from other contacts that CIIFAD and Tefy Saina were able to make, SRI trials and demonstrations began in Philippines, Cambodia, Sri Lanka, Sierra Leone, Gambia, India, Cuba, Bangladesh, Nepal, Laos, Myanmar and Thailand. In April 2002, an international conference for SRI assessment was convened in China, with support from the Rockefeller Foundation and CIIFAD. Participants from 15 countries shared initial SRI results and experience, with 60 Chinese participants. The conference was hosted by the China National Hybrid Rice Center with the China National Rice Research Institute, CIIFAD and Tefy Saina as co-sponsors. (The proceedings are available at: http://ciifad.cornell.edu/sri/proc1/index.html) 

 

Since the Sanya conference, another 15 countries have reported that SRI changes in managing plants, soil, water and nutrients can produce more productive and healthier rice plants: Afghanistan, Benin, Bhutan, Brazil, Burkina Faso, Guinea, Iran, Iraq, Mali, Mozambique, Pakistan, Peru, Senegal, Vietnam and Zambia. Of special interest have been areas where SRI was spread in conflict or post-conflict situations: Aceh province of Indonesia; Maoist-controlled areas in Nepal; the Batticaloa region of Sri Lanka; rural post-war Sierra Leone; and currently in southern Iraq, northern Afghanistan, and Timor Leste (formerly East Timor).

 

How this dissemination/diffusion of SRI has been accomplished is discussed under 16. below.

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3.  How Can SRI Benefit the Poor?

 

SRI was purposefully developed to benefit poor, resource-limited, food-insecure households who needed to get the most productivity attainable from the small amount of land they manage and from available supply of household labor, with less water if possible, and without having to buy external inputs (new seeds, fertilizer, agrochemicals) that can push them (further) into debt.

 

By raising the productivity of the land, labor, water and capital invested in the production of rice without requiring the purchase of external inputs, SRI is unique among contemporary agricultural innovations. It is accessible to poor households because they need only to change their thinking and modify familiar practices. SRI does not present the kind of barriers to adoption that have kept Green Revolution technologies from benefiting many of the world’s poor households. Presently, probably more than 400 million people in rice-producing areas of Asia, Africa and Latin America are afflicted with chronic hunger (Surridge, 2004).

 

How SRI can improve the lives of poor households has been reported from Cambodia:

  • In 2002-03, the NGO ADRA persuaded 100 farmers in a village near Siem Riep, whose average paddy yield was 1 t/ha, to try SRI with the guarantee that ADRA would compensate anyone whose yield fell below this average. According to Roland Bunch of World Neighbors, these farmers averaged 2.5 t/ha with SRI -- and not a single farmer needed any compensation (http://ciifad.cornell.edu/sri/countries/cambodia/cambadrepmay03.pdf).

  • In 2006-07, a Family Food Production project of the LDS Charities in Kampong Chhnang province got 146 farmers who had been averaging 1.06 t/ha to use SRI methods. Their average yield with SRI practices and reduced costs was 4.02 t/ha, and all exceeded their previous yield (Lyman et al., 2007). Such increases can transform the life chances of poor households (http://ciifad.cornell.edu/sri/countries/cambodia/camldsrpt07.pdf).

In India, the NGO PRADAN  introduced SRI into Purulia district of West Bengal state where just 4 farmers were willing to try the new methods in 2003. Next year, 150 farmers practiced SRI and almost 4,000 by 2007. A team from the India Programme of the International Water Management Institute (IWMI), evaluated SRI use in two villages in 2004, one of which had experienced severe drought. Even so, the average increase in yield was 32% (50% in the village with normal rainfall, and 11% in the drought-stricken one). Net income per hectare went up 67% on average, with 8% less labor required per hectare. One farmer had a 15 tons/hectare yield, as measured and weighed personally by the team leader. The IWMI report characterized SRI as a ‘pro-poor’ innovation (Sinha and Talati, 2007).

 

In northern Myanmar, the NGO Metta Development Foundation began introducing SRI in 2001 through farmer field school methods. Metta trained 5,000 men and women through FFS programs, providing hands-on training through each ‘school’ which lasted one season long. By the end of 2005, about 20,000 households were using SRI methods through farmer-to-farmer spread. On demonstration-learning fields (N=30) of 1 acre (0.4 ha) each, SRI yields averaged 6.5 t/ha, compared to farmers’ usual yield of 2 t/ha. On their own fields after training, even without using all the SRI methods, farmer yields averaged over 4 t/ha. Because their costs of production did not increase and rice production was little more than a break-even operation, farmers’ net income per hectare went up more than eight times, from 296 kg/ha to 2,585 kg/ha (Kabir and Uphoff, 2007). The number of SRI users in the region is now estimated at 50,000.

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3.1. Can SRI Also Benefit Larger Farmers?

 

Because SRI capitalizes upon potentials that already exist within rice plants and their seeds, there are no patents and no intellectual property rights limiting its use. The insights and practices of SRI are available to everyone, free of charge. Since the innovation is scale-neutral, anyone can utilize SRI methods -- small, middle and large farmers.

 

Initially, SRI was considered to be too labor-intensive -- requiring more labor input per hectare -- for richer farmers to be able or want to use the methods on large holdings. However, as discussed below, SRI is often labor-saving once farmers or laborers gain skill and confidence with the methods. The principles can be extrapolated and practices adapted for larger scale use. This complicates the assessment of SRI impacts on richer vs. poorer farmers.

 

With good instruction and supervision of laborers, giving them appropriate remuneration reflecting the contribution their skill makes to SRI results), and possibly with mechanization of some operations, SRI methods can be beneficial for larger, richer farmers as well as for smaller, poorer ones. To the extent that the gains from higher productivity and greater production have an impact on rice supply and lower rice prices over time -- making this staple food grain more freely and cheaply available -- this will benefit the poor, particularly in urban areas.

  • Already in 2004, one large progressive farmer operating in the Cauvery Delta of Andhra Pradesh state of India, has used SRI methods on >40 hectares (>100 acres). Though good training and supervision, he was able to attain a harvested yield of 11.15 t/ha, more than doubling the usual yield in the area.

  • In China in 2007, 110,000 hectares of SRI rice were cultivated in Zhejiang Province and 120,000 hectares in Sichuan Province. According to their Provincial Departments of Agriculture, larger farmers have been quicker to take up SRI than were smaller ones because they found that SRI could not only enable them to reduce seeds, water and costs, but also reduced labor. The latter consideration is particularly attractive to many Chinese farmers because industrial development is reducing the supply of labor for agriculture.

  • From the evidence available to date, we see SRI methods benefiting both rich and poor households in absolute terms. Because poor households have greater need and demand for income increments and for greater food and economic security, this means that relative benefits are greater for the poor. But opportunities exist for richer households also to benefit.

The net impact of SRI is complicated: To the extent that SRI can be more labor-intensive, requiring more labor input per hectare, this favors its use by smaller farmers who have relatively more labor than land. As a rule, large farmers shy away from labor-intensive production systems, preferring not to hire and supervise labor if they can mechanize production. Higher demand for labor benefits poor households in general by raising total income, in part from higher wages.

  • SRI need not be labor-intensive, however. Once farmers gain skill and confidence in the new methods, most find that they can reduce the amount of labor expended to grow their SRI crop, while also reducing seed, water and other inputs. This could work to the disadvantage of landless laborers, who would have less employment as hired workers to do transplanting or weeding, although probably more employment for harvesting.

  • A transition from labor-intensive to labor-saving production is particularly advantageous for small farmers, because this frees up time they previously had to devote to meeting their staple food needs, and they can put some of their labor to some other more remunerative use. (This was much appreciated by poor households in the Purulia district case reported above).

  • More important, smallholding households that are food-deficit, not producing enough of their basic food grain for an entire year’s consumption, benefit greatly from the higher yields of SRI because this can enable them to escape the cycle of indebtedness that keeps many of them in perpetual poverty.

    • Households that cannot feed themselves must borrow from moneylenders. They have to sell their rice harvest to these intermediaries at harvest time when the price is low to repay their high-interest debts. They later have to borrow money again when their basic food supply runs out, and the price of food is again high. SRI thus can help households break this kind of debt bondage.

  • To the extent that SRI can substantially increase total food supply, this will bring down the price of basic food grains for hundreds of millions of poor people. This would be the most pervasive and effective kind of anti-poverty intervention because the poor will then have more of their meager incomes to spend on other needs. To the extent that larger farmers utilize SRI methods to improve their production and raise their production, this contributes directly to alleviating the hunger and neediness of the urban poor.

  • We expect that over time, some of the key operations in SRI -- transplanting or other means of crop establishment, and weeding -- will become mechanized with small 2-wheel tractors. Direct-seeding is already being introduced with SRI methods, giving the same yield with a 40% reduction in labor requirements. A ridge-and-furrow system combined with direct-seeding is saving both water and labor. There will be many adjustments down the road, but we expect that improving basic-food production and freeing up land, water and other resources for other, more productive and remunerative operations will work broadly and sustainably to the benefit of poor households, both landless and with limited landholdings.

  • As discussed elsewhere, SRI concepts are being extrapolated and extended to other crops.  In particular, we note that the yields of finger millet (ragi, in India), one of the main crops for the poor in India and Africa, have been doubled, even tripled, with SRI concepts. If SRI concepts can improve the production of sorghum, maize and other crops, this will be a great boon to poor families. If richer farmers can also benefit from SRI, this does not subtract from the benefits that its concepts and methods can bring to the poor.

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3.2. How Does SRI Compare with ‘Best Management Practices’?

 

SRI was developed to benefit smaller, poorer farmers, to counter their problems of poverty, hunger, and environmental degradation. It was not conceived or presented as being in competition with what rice scientists call ‘best management practices’ (BMP). BMPs are heavily depending on purchased inputs and are thus beyond the reach of those rural households who are most in need of greater productivity and income.

 

However, when SRI practices are used to best effect, their results have matched or even surpassed those associated with ‘Green Revolution' technologies. This has ignited  considerable controversy, with some scientists defensively insisting that -- however beneficial SRI might be for poorer farmers -- these alternative practices are inferior to what can be achieved by using the results of modern plant breeding and inorganic soil amendments.

 

Critics have been particularly upset by the reports of occasional ‘super-yields’ with SRI methods as these are above what rice scientists have calculated to be ‘the biological maximum’ attainable from current rice genomes. Those who have worked with SRI in the field and with farmers who have used the methods (which critics have not) are persuaded that yields over 15 tons per hectare have been and can be attained with the methods, but they themselves do not consider such yields to be of much relevance. What count most are (a) differences in average yields; (b) comparisons with what farmers are currently producing; and (c) methods that are neither costly for farmers nor harmful for the environment.

 

Currently, scientists from Cornell University, Wageningen University in the Netherlands, and the International Rice Research Institute (IRRI) headquartered in the Philippines are undertaking a joint evaluation with agreed-upon protocols and methodologies to assess SRI methods in comparison with BMP in several countries over a three-year period. This should settle, once and for all, the scientific controversy surrounding SRI in comparison to BMP.

 

For the record, we note that in the Indian state of Tamil Nadu, where modern methods are currently widely used by a farming population that is well-trained and supported by extension services, the average paddy yield in Erode district is 7.4 tons per hectare. In the 2007-08 main season, the average yield with SRI methods was 10.75 tons per hectare, according to the state Department of Agriculture (http://www.hindu.com/2008/05/23/stories/2008052350990300.htm). In 2006-07, the new methods were used on only 500 hectares in that district; in 2007-08, the SRI area expanded to 13,000 hectares. For 2008-09, based on farmer enthusiasm over SRI results, the Department has projected a target SRI area of 40,000 hectares. In side-by-side comparisons, SRI produced 3.3 tons per hectare more than current modern agricultural methods, a 45% increase.

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4.  How Can SRI Benefit the Environment?

 

SRI methods are not only beneficial for people but also for the natural habitat and biodiversity.

  • The most direct benefit is through reductions in water requirements. Rice is the ‘thirstiest’ crop in the world, requiring several thousand liters of water to produce 1 kg of rice when using conventional rice-growing methods with continuous flooding. SRI alternative water management methods can reduce this by 25-50%, and sometimes by more.

    • The realization that rice does not require or produce its best when in standing water comes as quite a surprise to many persons, who have accepted the conventional wisdom. However, that belief is wrong, as shown by much research (Guerra et al., 1998).

  •  Because SRI methods do not require chemical fertilizer, they enable farmers to reduce their fertilizer applications, or eliminate them altogether, producing yields as good or better by use of compost. This can contribute to both better soil and water quality and to improved soil health and human health. Not all farmers are willing to change to fully organic sources of fertilization, but SRI training and experience encourage reduced use of chemical fertilizer.

  • An evaluation of 120 farmers in Cambodia who had used SRI methods for three years, with a doubling of yield, documented that farmers reduced their fertilizer use by 43%, and their use of agrochemicals by 80% (Tech, 2004).

  • When SRI was introduced to farmers in eastern Indonesia under a Japanese-funded project, farmers were advised to cut their applications of fertilizer (nitrogen, potassium and phosphorus) by 50% compared to what was recommended by the government. With this reduction in fertilizer use and a 40% reduction in water use, farmers’ yields increased by 78% (3.3 tons/hectare) on average. These data are from 12,133 on-farm comparison trials covering a total area of 9,429 hectares (Sato and Uphoff, 2007).

Where SRI can raise rice yields by reducing fertilizer use, this will improve soil and water quality. In some rice-growing areas of China, the levels of nitrate in the groundwater supply are now many times higher than the maximum acceptable level established by the U.S. EPA. In some communities, the nitrate level in ground water supply is 300 parts per million (ppm) and rising; EPA’s current allowable nitrate concentration in ground water is 50 ppm.

  • Because SRI methods increase rice plants’ resistance to pests and diseases, farmers find that they can reduce or even eliminate their use of agrochemicals, many of which have adverse effects on soil and water quality. An evaluation of SRI in Vietnam in 2005-06 by the Ministry of Agriculture’s National Integrated Pest Management (IPM) Program found that with SRI methods, the prevalence of major pests and disease was reduced by 40 to 80%.  The number of sprayings per crop was cut from 2.75 to 1.25 (Ngo, 2007).

 

 

Spring season

Summer season

SRI

Farmer

Difference

SRI

Farmer

Difference

Sheath blight *

6.7

18.1

63.0%

5.2

19.8

73.7%

Leaf blight *

--

--

--

8.6

36.3

76.5%

Small leaf folder **

63.4

107.7

41.1%

61.8

122.3

49.5%

Brown plant hopper **

542

1,440

62.4%

545

3,214

83.0%

Average

 

 

55.5%

 

 

70.7%

* Percentage of plants     **Insects/m2                      Source: NGO (2007).

  • SRI thus makes it possible for farmers to grow more and better crops by extracting less water from natural ecosystems and by reducing the application of chemical fertilizers and sprays. These environmental benefits can also contribute to better human health.

  • SRI methods can also contribute to the conservation of biodiversity. This is most direct and obvious with respect to the biodiversity of rice species, making traditional local varieties more productive, profitable, and thus competitive with high-yielding varieties and hybrids (see discussion under #8). The soil and water management practices of SRI, including the increase of soil organic matter, should have very positive impacts of biodiversity of the soil biota, a kind of biodiversity that receives little attention. SRI has been used in the peripheral zones of national parks and protected areas in Madagascar and Indonesia to help save rain forest ecosystems, giving farmers an attractive alternative to slash-and-burn cultivation, so that habitat can be preserved for much-admired endangered species: lemurs, orangutans, chameleons, and various endemic birds, reptiles and amphibians. By raising the productivity of farming systems in marginal areas, SRI can buffer the conflict between parks and people.

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4.1.  What Is the Impact of SRI on Greenhouse Gases?

 

This has not been evaluated systematically, so no claims are made about SRI’s net impact on the emission of greenhouse gases (GHG) that contribute to global warming. But there are reasons to expect that SRI will contribute to slowing the accumulation of GHG. This remains to be evaluated thoroughly and precisely, however.

  • Agriculture is one of the major contributors to the production and atmospheric accumulation of methane (CH4), which is produced by soil organisms (methanogens) that live under anaerobic conditions, i.e., in the absence of oxygen. The flooding of rice paddies to grow irrigated rice is one of the major sources of methane within the agricultural sector (Neue, 1993). Flooded rice paddies apparently account for between 6 and 29% of the methane for which human beings are responsible (http://www.ciesin.columbia.edu/TG/AG/ricecult.html).

  • The belief that rice requires continuous flooding for best results (DeDatta, 1981) is contradicted by SRI experience and scientific evaluations. That water stress reduces yields, well documented in the scientific literature, has been determined from evaluations of rice plants that were grown entirely with continuous flooding, so their roots are not well developed (as with SRI methods) and are, in fact, degenerating (Kar et al., 1974).

  • Rice plants perform better when they are not flooded continuously, and even better when the other SRI practices are followed. SRI demonstrations are already beginning to dissuade rice farmers from their long-held conviction that ‘the more water, the better.’ This is beneficial for the environment by reducing water applications to rice crops and it will also diminish methane emissions. SRI can make it profitable for farmers not to flood their rice fields.

  • Converting rice production from continuously-flooded to intermittently-flooded soil, or even to mostly aerobic soil conditions, will reduce methane production, so this is an environmental ‘plus’ for SRI. However, it is not known with any precision whether -- when rice soils are no longer kept anaerobic -- there will be an offsetting generation of nitrous oxide. This is an even more potent GHG that is produced by certain microbes under aerobic soil conditions. Because N2O molecules are many times more harmful than CH4 molecules in the atmosphere, we need to know whether and how much nitrous oxide is produced from SRI fields compared to the methane produced from conventionally-flooded fields.

  • Because SRI reduces or eliminates the use of chemical N fertilizers -- relying on organic matter as the main source of nitrogen for plant and soil microbial nutrition -- there is reason to expect that there will be little if any additional nitrous oxide produced as a by-product of SRI practices. Evaluating this systematically and scientifically should be a priority for all those who are concerned about abating the dynamics that are currently contributing to GHG accumulation and global warming.

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4.2. How does SRI Relate to Controversy about Genetically - Modified Organisms?

 

There is no direct connection between SRI practices and growing genetically-modified (GM) crops, since SRI practices could be used, probably beneficially, to grow such crops. SRI is not associated with any particular kind of rice because its methods give advantages with practically all varieties (genotypes).

  • However, it is already seen that the productivity gains with SRI methods are greater than the proposed gains from genetic modification of rice plants. This reduces the need for GM work to raise yields at some point in the future. Since SRI methods give greater resistance to pests and diseases, genetic modification appears less necessary to achieve crop protection than before the benefits of SRI management became known.

  • The development of GM crops is likely to be a long and protracted process, also very costly. It is not without risks to the environment (gene flow, impacts on biodiversity) and possibly to human health. Health risks have not been demonstrated, but neither is there sufficient evidence and experience to rule out their possibility. The ‘precautionary principle’ urges proceeding slowly where irreversible effects could be created.

  • With SRI available, there is no imperative to hurry the development and release of GM rice varieties. Moreover, the large cost of investing in GM is now less justifiable economically with the SRI option available. This implicit competition may be one reason why there has been so much opposition to SRI from some scientists. Villagers in northern India are already concluding that they do not need new rice varieties when SRI meets their needs more cheaply (http://groups.google.com/group/sriindia/browse_thread/thread/8676c5d8f8e68c82). (Unfortunately in this article there is confusion between  GM varieties and high-yielding varieties (HYVs) produced through conventional breeding methods.)

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5. What Are the Requirements for SRI?

 

SRI does not require any purchases or credit, although its results are significantly enhanced by having access to and using implements that aerate the soil at the same time that that they control weeds.

  • Water Control: The main requirement for SRI success is a sufficient degree of water control, to be able to apply small amounts of water regularly and reliably, or to be able to flood the field and then drain it after a few days, being sure to be able to re-flood it after a few more days. In some places, farmers’ access to water is too unreliable for them to be willing to operate with ‘a minimum of water,’ as Fr. de Laulanié recommended. Or they are cultivating where there is continuous inundation of fields from rainfall, such as in monsoon climates where there is poor general drainage. Or they may have low-lying fields and very heavy clay soils, so that it is difficult or impossible to evacuate the water and the fields are perpetually saturated. With saturated soil conditions (anaerobic or hypoxic), there will be less than the maximum benefit from SRI practices.

    • The most favorable circumstance for practicing SRI is where water is pumped from a groundwater source or from a river or reservoir. This gives a farmer both the means to control and limit water (turning the pump on or off) and the incentive (saving money for pump operation) -- provided that electricity supply, for example, is reliable.

    • Where water control is difficult, such as in the middle of a large irrigation system with other farmers practicing continuous flooding, digging drainage channels within the field and making raised beds can buffer the SRI plants from too much water in the root zone. While precise water control is ideal for SRI, farmers can adapt their soil, plant and water management practices to benefit from these methods under less-than-ideal conditions.

  • Labor: A second requirement is that the farmer has enough labor and time to invest more of both initially while learning the methods. Any new practice requires some investment of time and effort for learning. Farmers starting SRI may need 20-30% more labor the first season, although in some there is labor saving even with this first use, because there are so many fewer plants to raise and transplant. Mechanical hand weeding requires more labor at first, but farmers report that they offset this with labor saving from stopping chemical spraying. As discussed next, more labor is required for making and applying compost compared to buying and spreading chemical fertilizer; but the amount of time required depends very much on availability of biomass. Farmers starting out with SRI need to be prepared to invest more labor initially. This can be a barrier to adoption for poor households which lead a hand-to-mouth existence, not being able to afford such an investment even if it is (and they know it is) profitable for them to use the new practices (Moser and Barrett, 2003).

  • Biomass: A third requirement is supply of biomass, if farmers want to rely heavily or entirely on organic sources of soil fertility enhancement, rather than continue using chemical fertilizer ‘straight from the bag.’ The compost that can substitute for fertilizer can be made from any available biomass (rice straw, weeds, loppings, possibly manure, etc.), but this is sometimes in short supply, especially for farmers whose fields are large.

    • SRI does not require organic fertilization, but the yields are best when soil fertility is supported by organic inputs to the soil system. It would be very desirable to have better tools and implements for collecting, transporting, shredding, processing and applying decompose biomass (compost). Many these are currently of unimproved design and are not very efficient means for managing biomass in terms of the labor requirements.

    • Making SRI more accessible and productive will depend on developing better tools and implements to raise labor productivity in these processes, and on ways to grow or access more voluminous and convenient stocks of biomass. Little research and development has gone into these two requirements for efficient, relatively easy reliance on organic means of soil fertility enhancement.

  • Crop Protection: Where both plants and grain are increased, there is always potential need for more crop protection measures to protect against pests and diseases. In general, farmers’ reports and evaluations support the observation that the incidence of and damage from pests and diseases are less with SRI crops (see data on page 12). However, SRI farmers need to be prepared to deal with such hazards. Since SRI is not necessarily ‘organic’ in its practice, chemical protection is an available means, except for farmers committed for personal or economic reasons to ‘organic’ production.  The most difficult problems encountered so far have been with vertebrate pests (rats, or in one case in Peru, snakes). We recommend that farmers utilize integrated pest management (IPM) practices and strategies as much as possible.

  • Motivation and Experience: The most important requirement for SRI success is that farmers be motivated and willing to invest more labor and thought in their rice production -- if they can get sufficient payoff from this. If farmers already know how to grow rice, then learning SRI can be very quick, provided they are motivated to improve their production and are willing to make this happen. If a farmer does not yet know how to grow rice, it can take years for him or her to acquire the skills, knowledge, habits and insights, even reflexes, needed to grow rice successfully. Farming is truly a skilled occupation, drawing on a lot of tacit knowledge. If one already knows how to grow rice, then explanations for the reasons for making changes in past practices, as well as some exposure to the new practices, visiting existing SRI rice fields and/or talking with experienced SRI farmers, will suffice to empower farmers to use the new methods without extensive training or laborious learning.

  • Appropriate Inputs: As with all agricultural practice, various inputs are needed. Because SRI methods enhance the productivity of practically all rice varieties, farmers can usually continue using the same seed as before. If they can make and apply sufficient compost (even just 2 tons/ha can suffice to enhance supportive soil biological processes), chemical fertilizer need not be purchased. Usually agrochemical crop protection (pesticides, etc.) is unnecessary. So the main input recommended is a soil-aerating hand weeder. If this is not available or too expensive, hand weeding or herbicides can be used to control weeds.

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5.1. What Are the Limitations for SRI?

 

Following from the preceding review of requirements, the main limitations for SRI use will be:

  • Water Supply and Control: While SRI reduces water requirements, no plants can grow without water. So some supply of reliable water is needed. Also, there should be some means of draining off excess water, so that soil remains mostly aerobic, with a good supply of oxygen. Where no water is available, SRI is not possible. Where there is no control over water supply, or no drainage facilities if water is abundant, SRI would not be recommended.

  • Temperature: Plants also require warmth for their growth. If temperatures are very cold, SRI may not be feasible -- although it may be possible to practice SRI by starting with older transplants (15-20 days, or even 25 days under very cold conditions that do not freeze the plants). A version of SRI developed at Northeast Agricultural University in China, called 3-S, uses 45 days in a system that has expanded to tens of thousands of hectares in Heilungjiong Province adjoining Manchuria. Seedlings, started in plastic greenhouses while there is still a foot of snow on the ground, are planted singly, with wide spacing and reduced irrigation, using as much organic matter as possible, with much-improved yields.

  • Labor Constraints: If there is not enough labor available, or not enough patience to learn the new methods and to treat young seedlings carefully, SRI methods will not be successful. Initially there may be some resistance from hired laborers to using the new methods, but usually within a few days, they report that the methods of transplanting are easier, and even the weeding operations with the push-weeder are usually considered an improvement over weeding by hand.

  • Crop Pests: A pest problem that has been identified in northern Thailand is certain kinds of root-feeding nematodes, which become more abundant when the soil is not kept flooded all the time. This pest should be controllable by modifying the water management, flooding the fields for more time than would be recommended with SRI while still drying them enough to have some benefit of soil aeration.

    • In Southeast Asia, the golden snail is a major pest for many rice growers. One SRI farmer has worked out a water management schedule compatible with SRI where the soil is kept just flooded enough to keep snail eggs from hatching until the young SRI plants are 20 days old. Then he dries the field so that the snails hatch and begin feeding on all the young weeds that emerge. SRI rice plants are enough older and tougher by this time that the snails prefer the tender new weeds. With these practices, the farmer says he can get the snails to do his weeding for him.

These examples of pest control underscore a general statement about the use and spread of SRI. We do not look upon the dissemination of SRI as a matter of extension -- spreading a set technology to any and all farmers -- but as a matter of problem-solving -- where principles are applied and practices are adapted to local conditions. In America, we say that there are two kinds of lawyers: can’t-do lawyers and can-do lawyers. SRI calls for can-do agronomists, who know what things cannot or should not be done, but who figure out how to achieve crop production and protection goals with appropriate modifications in general rules and recommendations.

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6. What Are the Reasons for Changing Current Rice-Growing Practices?

Older seedlings, being larger, are easier to handle. However, once the plants have started their fourth phyllochron of growth, generally about the 15th day after seeds are sown in the nursery, as discussed under FAQ #14, they lose some of their potential for tillering and root growth. The older that seedlings become, the less of their original potential they retain. Young seedlings, when managed with the other SRI practices, can have 50 tillers and corresponding profuse root growth, or even up to 100 tillers or more, compared with the 5 to 10 or at most 20 tillers that ‘normal’ rice plants have, i.e., starting with seedlings 3 or 4 weeks old or even older.

With usual transplanting practices, older seedlings are removed from a nursery that has been flooded so the seedlings have start in a soil environment that lacks oxygen. Little care is taken to protect their roots, and once seedlings are removed, they often lie in the open for hours or even days before being transplanted into the field, with desiccated roots that have dried out. Seedlings are pushed down into flooded soil having little oxygen, with their root tips inverted upward from being are plunged into the soil. These practices cause what is called ‘transplant shock,’ a well-known effect that causes plants to languish for 7-10 days, or even longer, before growth resumes, and the plants can become yellowish for lack of nitrogen.

 

Growing seedlings in well-oxygenated nursery soil enhances performance (Mishra and Salokhe, 2008). SRI seedlings are carefully removed from their nursery, keeping soil and seed sacs attached to their roots. They are transplanted quickly and gently, and roots are not allowed to dry out in the sun. They are placed gently into aerobic soil, laid in horizontally and shallow (1-2 cm), so that plant growth is resumed almost immediately. This gains 7 to14 days of vegetative growth before flowering, which adds disproportionately to tiller number and root growth.

When rice plants are crowded together, within hills of 3-6 plants packed together in a clump, with little space between hills, this reduces the amount of sunlight that can reach the lower leaves. Measurements made in 2003 by Dr. Anischan Gani at the Indonesian Rice Research Institute at Sukamandi found that with typical close spacing of rice plants, not enough illumination reaches the lower leaves in the canopy to support photosynthesis. This means that these leaves, instead of contributing to the plant’s pool of energy, are taking energy from it, parasitically.

 

Moreover, we know that rice roots rely mostly on the plants’ lower leaves for their energy supply, to support their metabolism (Tanaka, 1958). So crowding plants together impedes whole-plant photosynthesis and undermines the growth and functioning of root systems. When there are fewer plants per square meter, all rice plant leaves are active in photosynthesis, and root systems are well-nourished by the lower leaves, which makes all of the plants more productive. Each plant has more tillers, with more grains, and usually heavier grains. This change in phenotype more than compensates for having fewer plants in total.

Rice is an unusual plant in that it can survive under flooded conditions by having some of the cells in the cortex of their roots disintegrate. (The cortex is made up of cells around the column of vascular tissues in the center of the root that transport water and nutrients upward, the xylem, and transport food supply downward, the phloem). This disintegration creates aerenchyma (air pockets) that permit air, especially oxygen, to diffuse passively from the above-ground parts of the plant eventually to the root tips, which need energy and oxygen to continue their growth. Under flooded conditions, 30 to 40% of the cortex may disintegrate this way, impairing to some extent the transport of water, nutrients and food supply within the root (Kirk and Bouldin, 1991). So, while rice plants can adapt to hypoxic, oxygen-less conditions, they do not perform at their best under such conditions. Under continuous flooding, about 3/4 of the root system degenerates by the time when the plant flowers and begins grain formation and filling (Kar et al., 1974).

 

Nobody knows for sure when or why the flooding of paddy fields began. Probably rice was grown in fields with saturated soil because no other crop could be grown there. Over time, rice was planted in fields that were intentionally flooded. The main benefit of flooding is weed control. Other plants, including weeds, are less able to grow under these conditions. Growing rice in flooded fields requires less labor than does rice grown in upland, unirrigated fields where weed growth can be prolific. If weeds can be controlled by other means than flooding, it is seen from SRI experience that much higher yields can come from rice plants grown in aerated soil, where rice roots instead of degenerating grow larger, deeper, and function better.

The answer to this question follows from the previous one. The use of rotating hoes or conoweeders to control weeds gives farmers a ‘bonus’ from active soil aeration, which enhances plants’ health and crop yield. While weeds can be controlled or removed by hand weeding or use of herbicides,this foregoes the benefits of soil aeration that promotes root growth and the abundance, diversity and activity of beneficial soil biota.

The answer to this derives from the foregoing discussion. SRI was developed by Fr. de Laulanié with fertilizer being used as the source of supplementary soil nutrients. But when small farmers in Madagascar could no longer afford fertilizer, he recommended using compost, which gave better results. Factorial trials have clearly confirmed this (Randriamiharisoa and Uphoff, 2002). Compost is more than just an alternative source of nutrients, valued for the amount of nitrogen, phosphorus and potassium it contains, as with chemical fertilizer. In addition to macronutrients (N, P and K), compost contains a host of micronutrients (iron, zinc, copper, molybdenum, etc.). It serves as a more balanced and more complete source of nutrients for soil organisms as well as for the plant itself. By better supporting soil organisms and the complex food web that operates underground in a healthy soil, compost contributes to better soil structure and functioning. There will be more pore space, so both air and water can be well-distributed throughout the soil volume. This porosity enhances the soil’s capacity to absorb and hold water, so rainfall does not just run off, carrying topsoil particles with it and eroding the amount and value of the soil. Soil biological activity supports the recycling of nutrients in the soil and the movement of nutrients from the ‘unavailable’ portion of the soil to become ‘available’ in the soil solution (Bonkowski, 2004; Doebbelaere et al., 2003; Turner and Haygarth, 2001; Thies and Grossman, 2006).

For a variety of reasons, rice plants grown with SRI methods are more resistant to pests and diseases, making it less or not cost-effective for farmers to use agrochemical means of protection. Commonly there is not enough damage and loss to justify the expenditure and labor for spraying. One possible explanation for SRI resistance to pests is that plants are grown in unflooded soil will have more uptake of silicon. This would account for the stalks (tillers) and leaves on SRI plants being tougher and stronger, resisting being blown over and lodged by strong winds and rain. Insects would also be deterred by this particular quality.

 

A theory called trophobiosis, proposed by a French agricultural scientist (Chaboussou, 2004), is consistent with what we observe with SRI, because it uses little or no chemical fertilizer and also little or no agrochemicals. According to Chaboussou’s theory, plants’ vulnerability to attacks by insects, bacteria, fungi, even viruses, is directly a consequence of imbalances or deficiencies in the plants’ nutrition. This is associated with shortcomings in the plants’ metabolism which is supposed to (a) convert amino acids into more complex protein molecules, and (b) metabolize simple reducing sugars into complex polysaccharides.

 

When nitrogen fertilizer is provided to plants, they take up more N and synthesize amino acids, the building blocks for proteins. But with imbalanced nutrition, they will not be able to quickly and effectively convert amino acids into proteins. This leaves a surplus of amino acids in the plants’ sap and cell cytoplasm, which is attractive to insects, pathogenic bacteria and fungi, even viruses. Similarly, with the application of pesticides, particularly chlorinated ones, plants’ metabolism is interfered with so that the simple sugars created through photosynthesis do not get consolidated quickly and continuously into polysaccharides. This produces an abundance of sugars in the sap and cytoplasm which offers pests and pathogens an opportunity to feed easily and expand their populations. ‘Surpluses’ of amino acids and simple sugar make plants vulnerable to predation and disease.

 

This there is supported by research published in the peer-reviewed literature going back many decades. Chaboussou is not an advocate of ‘organic’ practices because he proposes that any nutrient deficiencies which can impede metabolism should be remedied, by inorganic means if organic supplies are not available. More research should be done on the theory of trophobiosis, which has been largely overlooked or ignored by research institutions, and on the pest and disease resistance mechanisms of SRI rice plants. These are relationships and explanations that warrant systematic and objective evaluation. Meanwhile, the phenomenon of SRI crop resistance to pests and diseases, while not always observed, is confirmed by many farmers from experience.

SRI was developed with and for farmers n Madagascar who transplanted their rice. But nothing in SRI theory requires transplanting. The principle is that rice roots, key to the plant’s future growth, should be treated very carefully and should be protected from trauma and damage. Rather than try to change their method of crop establishment, the millions of farmers who now transplant their rice are encouraged to change their timing, spacing, etc. Farmers who are not wedded to transplanting, or who have labor shortages that make transplanting difficult to utilize, have been adapting SRI concepts and methods to direct-seeded crop establishment methods, coupled with the other SRI practices. Their main objective is to reduce labor requirements. They will try to achieve this goal even if it means that their paddy yield may be somewhat reduced because they are most concerned with favorable economics, not just agronomics.

 

One method, developed by a Sri Lankan farmer (Ariyaratne Subasinghe) and evaluated by a rice scientist at Tamil Nadu Agricultural University in India (S. Ramasamy), is based on broadcasting pregerminated seed on a muddy, leveled field. Ariyaratne uses about five times more seed thatn if he established his SRI crop with transplanted seedlings, i.e., he broadcasts see at a rate of about 25 kg per hectare instead of establishing a nursery with 5 kg of seed per hectare. When the young plants are 10-12 days old in the field Ariyaratne simply ‘weeds’ it as if he had transplanted it with spacing of 25x25 cm. This ‘weeding’ radically thins the stand of rice, eliminating about 80% of the young plants. It leaves them in a square geometrical pattern, with usually one plant at the intersections of the weeding passes, and sometimes two or even three. Occasionally there is no plant within this intersected space, but then adjoining plants grow larger to fill in any open space. The goal is to have a sparse, evenly and widely spaced plant population.

 

This methodology can reduce labor requirements for SRI by 40%, according to Dr. Ramasamy at TNAU, because there is no need to construct and manage a nursery, and also it eliminates the task of transplanting (http://ciifad.cornell.edu/sri/countries/india/intnramasapster06.pdf). All the farmer has to do is broadcast seed and then ‘weed’ the field just as he would have been done anyway after transplanting the crop. Ariyaratne says that he is confident of getting a yield of 7.5 tons/hectare. While this is perhaps less than from a more carefully managed field, he has many competing demands for his labor time, and this gives him a respectable harvest with a much reduced expenditure of labor.

 

This discussion underscores once more the importance of flexibility and innovativeness to capture the benefits of SRI under specific local conditions. This Sri Lankan farmer has two hectares of rice land, and his operation is labor-constrained since his children are still young. Economizing on labor requirements is a rational strategy. Farmers in various countries are trying SRI concepts out with innovations like raised beds, zero-tillage, intercropping with potatoes, seedbed solarization, etc. These versions are not in conflict or competition with SRI, but are welcome adjuncts to the extent that they help farmers solve their problems and meet their goals.

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7. What Are the Main Economic, Social and Other Benefits with SRI?

(Environmental Benefits are discussed under #4 above)

 

SRI has been sometimes dismissed or ignored on the grounds that the results reported are "too good to be true." This is an unempirical and uninformed basis for rejection, however, relying on a priori reasoning, not evidence. Use of SRI methods will not always produce all of the desired or reported benefits. However, it offers a remarkable number of desirable outcomes that come at little or no incremental cost.

  • Increases in Yield: Yield (grain per hectare) is usually treated as a summary indicator of productivity. But this represents only the productivity of land, not the productivity of labor (earning per day), or of water (crop per drop), or of capital (profitability). As a rule, farmers are interested in many considerations besides or beyond yield. But yield always attracts the most attention, regarding land as the scarcest factor of production.  Increases in grain yield achieved on-farm with SRI methods range from about 20% to 200%, and sometimes even more as seen in the data reported from Madagascar and Cambodia. Gains that are achieved with reductions in one or several inputs (labor, water, capital) are more significant than if they are attained with greater expenditure of resources. Usually with SRI methods, there is also an increase in the production of straw (biomass). This yield increase is very important for many small farmers, who use straw for fodder, thatching and other purposes.

  • Increases in Factor Productivity:  Output per unit of input is the most important economic measure, since achieving more output with greater expenditure inputs is of uncertain benefit. SRI is the only innovation we know of where the productivity of all the factors (land, labor, water, and capital) is raised concurrently. This has made SRI ‘suspect’ because economists believe that this is impossible, insisting that there is ‘no free lunch.’ But this premise applies to closed systems only, in which there must be diminishing returns. With SRI practices, energy and nutrient inputs come from biological activity which is free provided that certain conditions for organisms’ growth are met. This makes possible rather broad-based gains in factor productivity. Total factor productivity is hard measure and report in a summary manner because of difficulty of combining land, labor, water and capital, even in monetary terms, but evaluations of each factor show gains - more output per unit of input.

  • Reductions in Water Requirements: Because under SRI, irrigated rice is grown without continuous flooding, 25 to 50% less water is needed for growing a crop that produces greater output. Water productivity can be increased from two times to even six times (Ceesay et al., 2007). Under some soil conditions, it may not be possible to make such great gains in water saving, but under other conditions, as much as two-thirds of water has been saved.

  • No Need to Rely on Purchased Inputs: Farmers can use SRI methods successfully and cost-effectively (a) without buying and using chemical fertilizer, (b) without purchasing new seeds, and (c) not needing pesticides, herbicides or other agrochemicals to control pests, weeds and diseases. While fertilizer can be used with positive results, farmers if they have enough labor and access to biomass to make and apply compost can get better yield while improving their soil’s fertility. Rotary weeding not only eliminates weeds but also gives the added benefit of stimulating greater yield. And usually SRI plants are robust enough that chemical means of pest/disease control are not needed or worth the labor and expenditure.

    • Farmers should use the best rice varieties that are suitable for their environment  because starting with the best varieties gives them greatest return on their other resources invested in rice production. However, given that consumers will often pay more for local varieties of rice, it is often more profitable to grow traditional varieties than ‘improved’ ones. Also, if ‘organic rice’ commands a higher market price, the effort to nourish plants and soil with organic inputs becomes more remunerative. For farmers, minimizing their monetary costs for rice production has many advantages, including avoiding indebtedness and possible loss of land.

    Higher Returns to Labor - even Labor - Saving: Even when SRI methods require more labor per hectare than conventional practice, the higher yield almost always gives farmers higher production per hour or per day of labor, which is what will raise their family incomes. As noted above, SRI farmers often find that once they have mastered the methods, they are able to grow their larger crop without additional labor or even with less labor. Once farmers can save labor as well as seed, water and cost, this makes SRI very attractive.

  • Increased Farmer Net Income - Profitability: If farmers can achieve higher output with reduced cost of inputs, this raises incomes by more than their increase in production. A recent report from Cuba on production from 26 hectares on a cooperative farm showed a yield increase of only 15% -- from 4 t/ha to 4.6 t/ha. But net income (pesos/ha) was 70% higher (747.15 vs. 439.34) because seed costs were cut in half, fertilizer use was reduced by 94% (from 350 kg/ha to 37 kg/ha), 40% less water was used, a significant saving because irrigation water must be accessed by diesel pumps, the labor needed for transplanting was reduced from 16 persons to 5 persons (Socorro et al., 2008). Economic considerations here are more important than yield.

  • Reduction in Economic Risk:  The agronomic practices recommended for SRI - use of very young seedlings, just one plant per hill, reduced plant population, no flooding of the field, and reliance on organic fertilization - all appear risky. Two evaluations, however, that calculated actual risks based on data from large-scale random samples, have shown otherwise.

    • In an evaluation done in Cambodia for the German development agency GTZ with 400 SRI farmers and 100 non-SRI farmers in the same villages randomly selected in five provinces, an economic risk assessment showed that farmers’ risk of not achieving a target net income are lower with SRI practice. With SRI, the probability of not reaching an income of $US100/ha was calculated to be 17% vs. 42% with standard methods. Rice farmers were thus 2.5 times more likely to lose money with standard methods. The study concluded: "SRI is an economically very attractive methodology for rice cultivation with a lower economic risk compared to other cultivation practices" (Anthofer, 2004).

    • An evaluation for the International Water Management Institute (IWMI) in Sri Lanka based on 120 farmers randomly selected in two districts, half SRI and half non-SRI, calculated households’ economic risks with SRI vs. conventional practice according to three alternative wage levels, valuing labor as (a) zero wage, assuming use of only family labor; (b) the prevailing agricultural wage; and (c) the prevailing non-agricultural wage, an opportunity-cost assessment. In the first calculation, the probability that a household would end the season, either wet or dry, with a net economic loss was 9 times greater when using conventional practices than when using SRI methods. At the prevailing agricultural wage, this probability was 8.4 times greater, and if labor was valued at its non-agricultural opportunity cost, it was still 6.4 times greater  (Namara et al., 2004).

  • Less Susceptibility to Pests and Diseases:  Discussed under #3.2 above.

  • Less Vulnerability to Adverse Weather Conditions - Resist Climate Change? More evaluation needs to be done on this, but it has been often observed that SRI rice plants are:

    • More resistance to drought and water stress,

    • Better able to recover from flooding, provided they have gotten their root systems established before the flooding occurred.

    • More resistant to storm damage and lodging, to being knocked down by strong rain and high winds.

    • Better able to tolerate extreme temperatures, provided their root systems have gotten well established in the soil.

Given the growing variability in weather patterns and the more frequent occurrence of ‘extreme events’ it will become more and more important in the 21st century, especially for poor, resource-limited households, often cultivating in the most vulnerable regions, to have crops that can withstand as much as possible the adverse effects of climatic stress.

  • Shorter Crop Cycle - Quicker Maturation with Higher Yield: SRI farmers in most countries report that their SRI crop reaches maturity 5-10 days sooner, for any given variety, than rice crops grown with standard practice. This means that farmers can harvest sooner; they reduce the amount of water they need to grow their crops; they can reduce their crop’s exposure to storms or other climatic hazards and to pest and disease damage which often comes at the end of the season. This should be evaluated more broadly and in more depth.

In 2005, 51 farmers in Morang district of Nepal who used SRI methods planted the same variety of rice (Bansdhan) which normally matures in 145 days with standard practices. An analysis of time-to-harvest showed that the 9 farmers who planted seedlings older than 14 days (because of labor or water constraints) harvested their SRI crop 6.5 days sooner on average. The 37 farmers who planted seedlings 10-14 days old, as recommended, harvested 14 days sooner, while the 5 farmers who transplanted seedlings only 8 or 9 days old got a mature crop in 124 days, three weeks less time than expected. Average SRI yield was 6.3 tons per hectare compared with 3.1 tons with usual farmer practices, and with less time.

  • Higher Milling Outturn - A Bonus:  It was noted already that farmers and millers find that SRI paddy rice (unmilled) gives greater output of polished rice (milled), because of:

    • Less chaff - fewer unfilled grains; husks with no grain inside have no edible value, and

    • Fewer broken grains - there is less shattered during the milling process. SRI grains are usually heavier and denser and resist breakage.

Millers in Sri Lanka in 2002 began offering SRI farmers, even before harvest, 10% higher price per bushel of unmilled paddy because they learned could get more than milled rice outturn from SRI paddy. An evaluation done at Sichuan Agricultural University in China confirmed this. SRI paddy rice averaged 16.1% more total milled rice outturn, and 17.5% higher head milled rice, i.e., whole grains (Ma 2004). An informal survey of farmers in a dozen villages in Tripura state of India in October 2007 found an average increase of 18% in milled (polished) rice per bushel of SRI paddy (unmilled) rice. This represents a 15% bonus on top of the higher production of paddy rice when SRI methods are used.o      

There are numerous reports that consumers consider the quality of SRI rice to be higher, but we have no systematic evaluations on this. The Sichuan Agricultural University evaluation measured ‘chalkiness’ in SRI rice compared with rice grown conventionally. (Chalkiness is considered an undesirable quality of rice, and it also contributes to more breakage during milling.) SRI had 30.7% fewer chalky kernels, and 65.7% less chalkiness overall (Ma 2004). Since there is less breakage of SRI paddy rice when it is milled, there could well be higher protein content, as resistance to breakage is known to be associated with higher protein (Leesawatwong et al., 2004). There is also reason to think that there could be higher concentrations of micronutrients in SRI grain because the kernels are denser, i.e., heavier without being larger. This could also contribute to less breakage during milling. Since SRI roots are larger and reach more deeply into the soil, they would have much more capacity to acquire micronutrients. This would make the plants themselves healthier and better able to resist damage from pests and diseases. But there needs still to be more systematic work done on this benefit for which there is not yet very complete evidence. Recent research has shown that growing rice under unflooded soil conditions enhances copper, zinc, magnesium and manganese in the grain (Xu et al., 2008).

Apart from nutritional benefits still being assessed, we know that stopping continuous flooding of paddy fields should reduce mosquito-borne diseases like malaria and dengue fever. According to recent research, there is 10-15 times less uptake of arsenic by rice plants growing in unflooded fields (Xu et al., 2008). But this should be further investigated. We have been told by an NGO in the Philippines which works on women’s health problems that in Isabela province, northern Luzon, SRI practices have reduced women’s urinary tract and vaginal infections because they no longer must do transplanting and weeding crouching in deep stagnant water. Where the productivity gains of SRI permit farmers to reduce the amount of land devoted to rice production and to diversity farming systems, to produce more fish, fruits, vegetable, legumes and small livestock, this should not only improve household income but also nutrition from more diversified diets. For examples of such systems, see: http://ciifad.cornell.edu/sri/countries/cambodia/cambSidMPREng.pdf

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8. Is There Need for Any New or Special Varieties?

 

So far, we have found that SRI methods improve the performance of rice plants of all varieties, old and new, unimproved and improved, traditional and modern, local and hybrid - but not all equally. Some varieties respond more effectively to SRI management practices than do others, and farmers will naturally want to use whatever varieties of rice are most productive under their conditions. However, farmers evaluate productivity not only in physical or agronomic terms. They are most concerned about their ‘bottom line,’ so they will want to consider what prices they can get for their rice, and what will be their net income as a result.

 

The highest yields achieved so far with SRI methods have all with modern high-yielding varieties or with hybrids, many of which have been bred for tillering capacity, for example. However, many traditional local varieties have given very good responses to SRI management - 6-10 tons per hectare, and even as high as 12-13 tons per hectare in Sri Lanka. Because consumers usually prefer the taste, texture and other qualities of ‘unimproved’ varieties, they may pay two or even three times as much per kilogram for traditional kinds of rice. So these varieties grown with SRI methods can often be more profitable than higher-yielding varieties.

 

Working with partners in a number of countries, CIIFAD has been trying to support production and marketing of indigenous rice varieties grown organically, to promote rice that commands a higher price in the market and is more environmentally benign. In 2005, the SEED Initiative award, supporting entrepreneurship for environment and development, sponsored by IUCN, UNEP and UNDP, was given to CIIFAD together with the Koloharena farmer organizations in Madagascar, CEDAC and the farmer groups it works within Cambodia, and Oxfam-Australia and farmer cooperatives it has introduced to SRI in Sri Lanka. While SRI methods can be used with both ‘new’ and ‘old’ rice varieties, we hope that they will help to conserve rice biodiversity  by making local landraces more profitable and thus competitive with hybrids and HYVs.

 

At the same time, SRI methods make production with hybrid varieties more profitable, since these can give a very good yield response with SRI. SRI also raises the economic returns from planting hybrids by reducing seed requirements by 80-90%. (The high cost of hybrid seed is one of the barriers to adoption of hybrids for many farmers.) In Indonesia, in 2006 dry season on Bali, 24 farmers used SRI methods with Long-ping Chinese hybrids, and got an average yield on 42 ha of 13.3 tons/ha, compared with an 8.4 t/ha field when they used SRI techniques with usual practices (Sato and Uphoff, 2007). SRI thus makes hybrid varieties much more remunerative.

 

SRI is intended to give farmers more choices to improve their well-being and security. Those who want the highest possible yield will probably choose to use SRI methods with hybrids or modern varieties. Farmers thinking about their ‘bottom line’ will probably prefer to plant traditional varieties. CIIFAD and several partners in other countries are currently working with a small company in San Francisco, Lotus Foods, that imports and markets specialty rices throughout the U.S. Several lines of SRI organic/traditional rice are being developed with good packaging and quality control to gain market access and raise incomes for SRI farmers overseas.

 

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9. Does SRI Require More Labor? Not Necessarily - It Can Reduce Labor

 

Initially, when farmers are starting to learn the new methods, it takes more time to use them well. Handling tiny young seedlings, when farmers are used to handling larger, more mature ones, can be a little worrisome, and transplanting may go slowly. However, once farmers get accustomed to the new methods, they can do the practices more quickly. Depending on the difficulty of controlling water, applying small amounts of water regularly can take more time – or less -- than keeping the field always flooded. Overall we find that as farmers become comfortable with and more confident in SRI practices, this alternative system is labor-neutral, i.e., does not increase labor, or it can even become labor-saving, reducing labor requirements.

 

The evaluation of SRI by Moser and Barrett (2003) that first raised the issue of labor-intensity was surely correct for the villages surveyed in Madagascar. However, a subsequent evaluation by these authors with two other colleagues (Barnett et al., 2004), with a data base of 108 farmers having different lengths of SRI experience, found that while SRI methods required more labor initially,  by the fourth year there was a 4% average reduction in labor inputs per hectare, and by the fifth year, a 10% reduction. In countries outside of Madagascar, the transition to labor-saving has been usually more rapid and extensive than in Madagascar, for reasons not well understood.

 

Evaluations in Cambodia for the German aid agency GTZ (Anthofer 2004) and in Indonesia by a Nippon Koei technical assistance team (Sato and Uphoff 2007) have found SRI methods to be labor-neutral on average. While new SRI farmers require more labor to grow their crop, more experienced SRI farmers need less labor, so on average there is no change. Detailed evaluations in China (Li et al. 2005) and India (Sinha and Talati 2007), on the other hand, have shown average reductions in labor requirements, even from the first year. Reports on SRI use over larger areas in China and India have also noted that SRI is considered by farmers and officials to be generally labor-saving (Uphoff, 2007; The Hindu, January 1, 2008).

 

In India, a detailed evaluation in 2004 by researchers from Tamil Nadu Agricultural University of side-by-side plots on 100 farms in the Tamiraparani river basin, managed respectively with SRI and conventional methods, found that labor inputs per hectare were 8% lower with SRI (Thiyagarajan 2004). Interestingly, men’s labor inputs per hectare went up by almost 60% -- because men considered SRI weeding done with a mechanical weeder to be ‘men’s work,’ and accordingly they took over this activity. This reduced the amount of women’s rice labor by 25%.

 

A more important consideration is that farmers are continually finding ways to reduce their labor inputs with SRI, by improving the design and operation of weeders, by finding ways to reduce their labor requirements for nursery management or transplanting, by doing alternate wetting and drying of paddy fields rather than more laborious daily water management. So, the labor needs with SRI are ‘a moving target,’ not something fixed. Both farmers’ skills and the techniques or technologies they use with SRI are undergoing continuing change. So while farmers should always be informed that SRI will require more labor when starting out, there is reason to expect that this increase will be transitory or transitional, rather than necessary and invariant.

 

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10. "Background and Ideas involved in Organic SRI"?

 

Fr. de Laulanié developed SRI during the 1980s using chemical fertilizer because this was thought to be the best, or the only, way to achieve increased production at the time. When the government of Madagascar ended its subsidization of fertilizer in the late 1980s, the farmers with whom Laulanié worked could no longer afford to purchase fertilizer. So he and they began to enhance soil fertility with compost out of necessity. Happily, they learned that, in conjunction with the other SRI practices, they could improve rice yields using compost by even more than when using fertilizer. The compost was made with little or no manure since few of these farmers were rich enough to own cattle. Mostly the compost was made from rice straw and any other available biomass - weeds, grass, shrubs, tree litter, etc. - decomposed for 30 to 60 days.

 

Chemical fertilizer in conjunction with other SRI practices does enhance SRI yields. Compost is regarded not as a requirement for SRI by Association Tefy Saina, only an accelerator or booster.

 

Two versions of SRI have been developed: basic SRI, in which farmers’ reliance on chemical fertilizer is reduced as they increase the amount of compost added to the soil to support the crop; and organic SRI in which only organic inputs are used, under some marketing regimes qualifying the rice they produce for a premium price in the market.

 

Very often, farmers who have converted their cropping system, previously dependent on chemical fertilizer, to fully ‘organic’ production methods have had to go through a transition period when their yields decline for a while. Their soil systems usually need time to adjust to functioning without a supply of inorganic nutrients. Their soils need to build up their populations of soil biota, often depressed or unbalanced by the use of fertilizer. On the other hand, with SRI methods, we seldom see such a ‘transition’ phase. Usually, farmers who adopt SRI practice with greater or total reliance on organic fertilization right from the first year get an increase in yield, a ‘windfall’ from converting their soil from anaerobic status (without air) to aerobic conditions (well supplied with oxygen). 

 

With petroleum prices rising and higher prices for chemical fertilizer and other agrochemicals, there will be more and more interest in production systems that do not depend on these inputs. Also, there is growing concern for the quality of soil and water resources, and for soil health and human health. We can anticipate more and more demand from consumers for organic production methods in agriculture that produce food which is chemical-free. There will also be demand from citizens to reduce the build-up of nitrates in groundwater and surface water supplies, and to stop the accumulation of chemical toxins in our soil and water. Thus, we anticipate that the organic version of SRI is likely to gain in popularity - and productivity.

 

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11. Are There Any Environments in Which SRI Cannot Succeed?

 

So far, benefits from SRI practices have been seen in a wide variety of environments, but there must be some limitations on any biological process. There is not be equal advantage from the methods in all contexts, but it is remarkable is that SRI methods have been improving productivity in a wide range of circumstances.

  • In Madagascar, two large-scale factorial trials were conducted in 2000 and 2001 using standard scientific methods which validated the merits of SRI practices. Six variables (age of seedling, spacing, water management, etc.) were evaluated with random-block-design trials (N=288 and N=240) in two contrasting environments: in Morondava, at sea level, on poor sandy soils, with tropical climate; and in Anjomakely, at 1200 meters above sea level, on better clay and loam soils, with temperate climate. The patterns of yield response to the SRI practices evaluated respectively and in different combinations were essentially the same under both of these sets of agroecological conditions (Randriamiharisoa and Uphoff 2002).

  • In Nepal, SRI methods have been used successfully in the southern terai, which has a sub-tropical environment a few hundred meters above sea level, and up to 2,700 meters elevation, which presents much colder and limiting climate.

  • In Africa, we have seen good SRI results in the Gambia, a low-lying tropical environment (Ceesay et al., 2006), and in Mali in the Timbuktu region on the edge of the Sahara desert.

One of the remarkable things about SRI is thus its versatility, although we know that one should never assume that its methods will be successful everywhere. It is always necessary to try out the methods under specific circumstances to see how they perform. There are some contexts where we do not expect SRI practices to be successful, or every successful.·       

  • Cold climate: Young seedlings are vulnerable to cold temperature, so this can be one limiting factor. However, rice plants’ age is reckoned by biological progression, not calendar days. So in cold climates, one can start with ‘older’ seedlings, 15-25 days old, that are biologically equivalent to 8-12 day seedlings grown with warmer temperatures. A rice production system known as 3-S, devised by the late Prof. Jin Xueyong of Northeast Agricultural University in Haerbin, not far from Manchuria, has many similarities with SRI: single seedlings, wide spacing, reduced water, more organic matter. It uses 45-day-old seedlings grown in nurseries under plastic tents that are started when there is still a foot of snow on the ground. 3-S yields of 8-9 t/ha have enabled it to spread rapidly in northern China.  (Jin et al., 2005; http://ciifad.cornell.edu/sri/countries/china/cn3ssys.html). Cold temperatures can require some modifications of practices, but SRI principles can often be adapted to them.

  • Water control: If soil cannot be kept intermittently moist and mostly aerobic (oxygenated), there will not be much benefit from SRI practices. Very low-lying soils or continuously waterlogged soils are not suitable for SRI cultivation because aerobic soil organisms cannot prosper in an oxygen-less environment. In such areas, it may be possible to install drainage facilities to remove excess water, however. The increased economic returns achievable with SRI methods could make such investments financially feasible.

    • In Indonesia, farmers in the middle of large-scale irrigation systems with field-to-field irrigation flows have little control over their water supply. Accordingly, they have devised in-field soil management practices that enable them to use SRI methods effectively - raised beds within the field coupled with drainage channels around the inside edge of the field that help get rid of unneeded water more quickly.

    • In India, rainfall in the state of Tripura averages 2500 mm/year. It is seen there that putting small drainage channels across the length of SRI fields every 8 or 9 rows can keep the soil well-drained enough to use SRI methods successfully.

These examples show how adaptations and innovations can be introduced to deal with the constraint of excessive water. The numerous advantages of SRI can provide benefit:cost justification for investing in improving water control structures – gates, channels, canals and drainage facilities. They can also give incentive to farmers, once there is agreement on the advantages of using SRI practices, to form water user associations and to make the necessary efforts to manage their water supply to benefit from SRI opportunities.   

  • Soils: Soil characteristics have a significant impact on crop productivity in general; so also with SRI. Most of the good results with SRI methods have been seen on soils that are acidic (pH less than 6.0); generally there has been less good or even poor performance on alkaline soils. Initial evaluations of SRI in the Punjab state of India showed that its methods gave a 30% lower yield on soil affected by salinity, while yield on a heavy clay (‘sticky’) soil was 70% higher, and on three other soils, more typical, the yield increase averaged 62%. Research in India has shown that the application of compost (organic matter) on saline soils can alter pH and make them more fertile, probably also by improving soil structure to make root growth easier (Rangarajan et al., 2002). So it may be possible with extra applications of organic matter to make saline soils amenable to SRI production methods. Research in Mozambique on saline soils there gave some but not uniformly positive results (Menete et al., 2008).

It has been proposed by the current director of research at IRRI (Doberman 2004) that SRI will augment yield particularly on -- and possibly only on -- soil with high content of iron. This led to a conclusion that SRI benefits are limited to iron-rich soils. This is contradicted, however, by trials conducted across all 22 districts of Andhra Pradesh state of India by the state agricultural university (ANGRAU) in 2003 evaluating SRI on a wide range of soil types and under diverse agroecological conditions,. These trials showed SRI methods on average giving 2.5 t/ha more yield, with all districts showing yield improvement. The largest increases (4.8 t/ha) were on the interior, lighter, well-drained soils. Heavier, low-lying coastal soils showed an average increase of 1.8 t/ha (Satyanarayana et al., 2006).

 

PhD thesis research is currently being done in Panama by Marie-Soleil Turmel on the effects of soil type on SRI performance. Initial analysis of 70 data sets from across many countries indicates that SRI methods increase yield more, both absolutely and relatively, on soils that can be considered as ‘poor’ according to FAO classification, than on soils that are considered to be ‘good.’ If this conclusion holds up with further analysis and controlled field trials which Turmel is conducting during 2008-09, it will show SRI to be a very unusual innovation in that it is particularly beneficial for the poor, who usually must farm on poorer soils than are available to richer farmers.

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12. Can SRI Be Used in Upland / Rainfed / Unirrigated Rice Production?

 

This is an important question because much of the world’s poverty is found in rural areas where there are no irrigation facilities. If SRI is only beneficial under irrigated conditions, it would not redress the worsening of income distribution in the world. However NGOs working with farmers in Philippines, Myanmar and India have found that with suitable adaptations, SRI concepts and practices can give substantial increases in upland/rainfed rice production, even averaging 7 tons per hectare. This is a yield that most farmers with irrigation facilities would be happy to achieve.

  • Philippines: In 2003, Broader Initiatives for Negros Development  (BIND), an NGO in the province of Negros Occidental, did 20 on-farm replicated trials, with a popular local variety Azucaena, evaluating unirrigated SRI results with five different spacings (4 trials each) on a total area of 4,000 m2.  Three or four seeds were sown in hills at spacings of 15x40 cm, 20x40cm, 25x40cm, 30x40cm or 35x40 cm. Then 12-15 days after sowing, the hills were thinned to one plant each. The soil between the hills was mulched with leaves and branches of a leguminous shrub (gliricidia) to conserve soil moisture, suppress weeds, and lower soil temperatures so that soil organisms would become more abundant.   The highest yield was 7.7 t/ha with 20x40cm spacing. The average for all trials was 7.2 t/ha, compared with usual rainfed yields of 2 t/ha. Organic fertilization was used (chicken manure, seaweed foliar spray, and quite remarkably, virtually all of the tillers that the plants produced were fertile. See: http://ciifad.cornell.edu/sri/countries/philippines/binuprst.pdf

  • Myanmar: Starting in 2001, Metta Development Foundation, an indigenous NGO working in the northern (ethnic minority) states of Kachin and Shan began introducing SRI methods through farmer field schools. It adapted SRI practices to rainfed conditions because farmers in the region had no irrigation facilities. Average rainfed yield in the area is 2 t/ha. On farmer field school demonstration plots, where SRI methods were used as expected, average yields were over 6 t/ha. However, on farmers’ field even without full use of the methods, yields averaged over 4 t/ha and have been increasing year to year (Kabir and Uphoff 2007).

  • India: PRADAN, an NGO working in impoverished districts of Eastern India, started SRI with four farmers in 2003 in Purulia district of West Bengal, expanding to 150 farmers the next year. An evaluation team from the India Programme of the International Water Management Institute found that farmers who used all of the recommended methods, adapted for rainfed production, achieved 9 t/ha, and one reached 15 t/ha (pers. comm., S.K. Sinha, team leader; see Sinha and Talati, 2005). SRI use has kept on expanding in Purulia district, and a PRADAN report from Purulia in 2007 showed 3,793 households using SRI methods; 54% had yields in the 6-8 t/ha range, and 28% were over 8 t/ha -  where rainfed yields have usually been 2-3 t/ha. The five-year average SRI yield in Purulia was reported as 7.4 t/ha. PRADAN has begun introducing SRI in rainfed areas of Bihar, Orissa, Jharkhand, Madhya Pradesh and Chhattisgarh, also with good results.

·       There is reason to expect that the benefits of SRI, practiced with appropriate adaptations, can bring significant food security and enhanced income to households in areas without irrigation. Farmers need to learn not to hoard rainwater in their fields when the rains come, as this will lead to degeneration of their rice plants’ root systems. If they transplant, rather than do direct seeding, they should establish several nurseries, not just one, being willing to sacrifice all but the one of the nurseries, using only the one that has young seedlings with the best age when the rains come. This can be a ‘hard sell,’ but this decision can ultimately lead to greatly augmented yield.

 

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13. Can SRI Concepts and Practices Be Used Also for Other Crops?

 

SRI is not a technology with prescribed fixed practices, but rather a set of principles to be applied to promote greater root growth and more abundant, diverse and active soil biota. Beneficial effects on resulting plant growth can be anticipated if SRI methods are suitably adapted for other crop production. We have seen such extrapolations and extensions of SRI methodology to other crops particularly in India. We hope that the progress being made there can be extended to Africa and other parts of the world.

 

  • Wheat: This is a major cereal crop like rice and also like rice a grass-family species, so it should be amenable to SRI management practices. People’s Science Institute (PSI), an NGO based in northern India, has tried SRI methods with two varieties of wheat. In 2006, it recorded with two different varieties in on-station trials, 28% and 40% increases in yield, plus an 18% increase in straw, very useful to farmers in its region as cattle fodder. In 2007, the yield increase for 25 farmers making comparisons was 95% with irrigated wheat production and 63% without unirrigation. On System of Wheat Intensification in Uttarakhand, see Outlook Business, 10/18/08 (http://business.outlookindia.com/inner.aspx?articleid=2162&editionid=58&catgid=2&subcatgid=973)

  • Finger Millet: Two Indian NGOs have been working with this cereal crop which is very important for many millions of poor households: the Green Foundation in Karnataka state, and PRADAN in Jharkhand and other eastern Indian states. They have achieved yield increases of 100-200% by adapting SRI concepts and methods: young seedlings, wide spacing, soil aeration, increased organic matter, etc. People’s Science Institute had a 33% increase in finger millet yield  with SRI methods for 5 farmers in 2007, and a 60% increase for 43 farmers in 2007. Recently we learned that an elderly woman farmer in Tigray province of Ethiopia, independently using practices very close to SRI for her finger millet crop, got a yield of 7.5 t/ha, many times the usual yield in her region (Dr. Sue Edwards, Institute for Sustainable Development, Addis Ababa, personal communication). So we are hopeful that this crop which is so critical for so many poor people can be enhanced with SRI methods.

  • Sugar Cane: A number of farmers in Andhra Pradesh and Karnataka states have been adapting SRI methods to sugar cane production. One boosted his cane yield from 30 tons to 100 tons, with reduced costs. He transplanted 45-day-old sets raised in plastic bags with compost, rather than just putting long sets into the ground in rows. Spaced rows 6 feet apart instead of 3 feet, and reduced his plant material by 85%, as with SRI. Mulching was done to conserve soil moisture, suppress weeds, and lower soil temperatures to promote soil biota. Andhra Pradesh state government sponsored sugar cane SRI trials on 3,000 acres (Financial Express, 11/27/06).

  • Beans: People’s Science Institute in northern India reports 5 farmers getting an average yield increase of 43% with SRI methods adapted for rajma, the local name for kidney beans, in 2006. With 113 using these methods in 2007, learning from the first year’s experience, the average yield difference was 67%. So PSI will extend its experimentation and evaluation to still other crops.

Other farmers have tried SRI methods with cotton, mustard and other crops, but evaluation of changed management for these crops has not been systematic. The most unusual extension of SRI concepts to other agricultural production has been in Cambodia -- to chickens.

 

In the village of Pak Bang Oeun in Takeo Province, farmers say they now know the value of using compost on their paddy fields. Each household has its own compost pile near the house. Someone got the idea of putting bamboo fences around these piles and putting the villagers’ free-ranging chickens inside these fences. This way the chickens benefit from eating the insects and worms that are abundant in the compost, and they enrich the compost by depositing their manure.

 

During the summer when chickens suffer from and sometimes die from heat stress due to lack of water, they can be kept well-watered within the fence. Moreover, no birds are lost to dogs or to thieves. So farmers report that they can get more eggs and more meat from fewer chickens - if these are well-managed. They are seeing that, as with SRI methods for rice, when using better and more intensive management practices, it is possible to get ‘more from less.’

 

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14. What is the Significance of Phyllochrons?

 

The profuse tillering of SRI plants can be explained in part by an understanding of phyllochrons. When Fr. Laulanié learned, almost by accident, that transplanting very young seedlings can give much more robust and productive mature rice plants, it seemed quite mysterious. But then he happened to read a book on rice science by Didier Moreau (1986) and learned about the research on phyllochrons done by a Japanese crop scientist T. Katayama during the 1920s and 1930s but not published until after World War II (1951) -- and never translated into English.

 

Katayama discovered a periodicity in the emergence of tillers (stalks) studying rice, wheat and barley, which arises from the way that all grass-family (gramineae) species grow. Understanding phyllochrons can account for why rice seedlings transplanted before 15 days of age give a different growth response than do seedlings of older age. The most detailed discussion in English of phyllochrons is by Nemoto et al. (1995); for a short presentation, see Stoop et al. (2002).

 

The term ‘phyllochron’ comes from combining the Greek words for ‘leaf’ + ‘time.’ It denotes a period  during which a leaf (or more than one leaf) together with its associated root and tiller (or multiple roots and tillers beyond the 4th phyllochron) emerge from the meristem tissue which is located in the growing plant at the soil’s surface. A unit of leaf, tiller and root, together referred to as a phytomer, grows upward and downward from the plant’s meristematic tissue. While the plant’s shoot (its leaves and tillers) grow upward, its roots which emanate from the same cell-division process as the leaves and tillers grow downward into the soil.

 

The length of the phyllochron can vary: from 8-10 days if growing conditions are unfavorable, with many stresses, to 4 days if conditions are ideal and the plant encounters no stresses. If the growing conditions are good, a phyllochron can be just 5-6 days in length.

  • During the 1st phyllochron for rice (i.e., the first cycle of emergence), the first phytomer (leaf/tiller/root) is produced from the seed.

  • During the 2nd and 3rd phyllochrons, the plant does not produce additional phytomers (units of roots, leaves and tillers), so this is a time of apparent dormancy, which extends to about the 15th day if growing conditions are typical.

  • During the 4th phyllochron, a second tiller (with leave and root) emerges from the base of the original main tiller, described as the first primary tiller.

  • During the 5th phyllochron, one more phytomer containing a second primary tiller emerges, making the total number of tillers three.  

  • During the 6th phyllochron, an acceleration of growth begins, as two more phytomers are produced, a third primary tiller from the base of the main tiller, and a first secondary tiller from the base of the first primary tiller.

  • During the 7th phyllochron, there are now three more phytomers emerging, a 4th primary tiller along with secondary tillers from the 1st and 2nd primary tillers.

  • In the 8th phyllochron, there are five more phytomers, one more primary tiller, secondary tillers from the 2nd, 3rd and 4th primary tillers, and a first tertiary tiller from the 1st primary tiller. This sounds complicated, but it can be understood simply by looking at the diagram on the next page which Fr. Laulanié prepared from studying the work of Katayama.

  

This diagram becomes clearer by studying the numbers shown in the table on the below. Rice plants usually do not complete 12 cycles (phyllochrons) of growth before the flower and begin forming spikelets (potential grains) that if fertilized and properly nourished grow into grains. Whether a plant can maintain an accelerating rate of growth depends on the conditions under which it is growing. If plants are crowded together, they receive less sunlight and compete for soil nutrients, so this kind of semi-exponential growth is not possible. Also, if the soil is flooded, the plant roots degenerate for lack of oxygen and cannot support this kind of growth.

 

Pattern of Emergence of Rice Tillers over a 12-Phyllochron Sequence

 Sequence of Phyllochrons

Tillers

1st

2nd

3rd

4th

5th

6th

7th

8th

9th

10th

11th

12th

Total

Main tiller

1

0

0

0

0

0

0

0

0

0

0

0

1

First row of tillers

0

0

0

1

1

1

1

1

1

0

0

0

6

Second row of tillers

0

0

0

0

0

1

2

3

4

5

6

5

26

Third row of tillers

0

0

0

0

0

0

0

1

3

6

10

15

35

Fourth row of tillers

0

0

0

0

0

0

0

0

0

1

4

10

15

Fifth row of tillers

0

0

0

0

0

0

0

0

0

0

0

1

1

Number of tillers in each phyllochron

1

0

0

1

1

2

3

5

8

12

20

31

84

Number of tillers per 3 phyllochrons

1

4

16

63
(1 = 40) (4 = 41)  (16 = 42)  (63 = 43-1)

Cumulative total at each phyllochoron

1

1

1

2

3

5

8

13

21

33

53

84

  

Adapted from: Laulanié (1993 and 1993a)

 

The pattern of tillering shown in the table follows fairly closely what is known as a Fibonacci series, where the number for each period is the sum of the previous two periods. Such a series or sequence was made famous in the best-selling book, The DaVinci Code. The number of tillers produced in each period is approximately 2/3 greater than that of the previous period.

 

A rice plant that completes 12 phyllochrons of growth before the end of its vegetative growth phase (and moves into its reproductive phase -- which includes panicle initiation, flowering and grain-filling) would have 84 tillers. It would also have a very extendd associated root system because roots emanate from the same meristem cells that go through cell division to create the tillers and leaves. If transplanting occurs in the 4th phyllochron or later, we see empirically that the production of phytomers is diminished and that the rice plants then have fewer tillers and leaves and also fewer roots.

 

Thus, transplanting rice seedlings during the 2nd or 3rd phyllochron of growth -- approximately between the 5th and 15th days -- represents a kind of ‘window of opportunity.’ Roots will be less traumatized is transplanted in this period, and the plant when it resumes its growth will produce more phytomers in an accelerated way. When transplanting occurs later than about the 15th day (the exact date is affected by the length of the phyllochrons, a variable length), rice plants do not experience as much or as rapid growth. The factors that shorten - or length - phyllochrons have been discussed in Nemoto et al. (1995). The table below presents them analytically:

 

Growth Factors Affecting Phyllochron Length (*management factors)

 

Growth factors Positive influences Negative influences
"Biological clock" runs faster slower
Making phyllochrons shorter longer

 

Climate and Temperature

 

Temperature Warmer temperatures Colder temperatures
  unflooded soils better absorb solar energy* Flooded soils reflect and lose solar radiation *
Day-night variation Temperate climate Tropical climate
  Greater day/night Little day / night temperature
  Temperature differential differential, with continuous
  Less night-time respiration Night-time respiration
Day length Longer days Shorter days
  More solar radiation Less solar radiation

 

Plant Management

 

Spacing Wide spacing Narrow spacing
  Single plants / hill and fewer plants/m2 reduces competition among roots, more canopy growth * Manyplants / hill and more plants / m2 increases competition among roots, less room for canopy growth *
Solar energy (affected by spacing) Exposure to sunlight Shading
  More opportunity for photosynthesis, also more canopy aeration * Less opportunity for photosynthesis; reduced canopy aeration *

 

Water Management

 

Soil moisture Moist conditions Dryness / drought
  Intermittent irrigation meets plant needs while non-flooding stimulates Inadequate water creates serious stress on plant root growth *
Soil aeration Oxygen availability Hypoxia (lack of oxygen)
  Supports plant root growth and aerobic microbial communities * Slows root growth and causes root degeneration only anaerobic microbial communities *

 

Soil and nutrient management

 

Soil structure Permeable / friable Compacted
  Root growth facilitated; favors growth of soil microorganisms with more O2 and water * Root growth constrained; diminution of growth of soil microorganisms affected by management *
Nutrient supply Adequate / complete Limited / unbalanced
  Plant growth needs can be met on demand * Plant root and shoot growth constrained
Soil organic matter Abundant Scarce
  Supports diverse and abundance soil microbial communities that in turn improve plant nutrition and protection * Limited growth and productivity of soil microbial communities, affected by too much inorganic nutrient supply and/or too little organic nutrient supply *

 

More research remains to be done on phyllochrons and their effects on growth. There has been considerable research on phyllochrons in wheat, e.g., special issue of Crop Science (1995), 35:1, and on forage grasses, especially in Australia. However, there has been little consideration of rice phyllochrons except by scientists in Japan and China. Research has been done along similar lines in terms of ‘degree-days,’ but these are not linked to plant physiology as closely as are phyllochrons. For SRI, understanding phyllochrons helps explain why use of young seedlings has such a srong positive effect, well validated empirically (Randriamiharisoa and Uphoff, 2002). The rapid tillering and root growth which is possible with the set of SRI practices is not seen if older seedlings are used and rice plants are grown under continuously flooded conditions with degenerating plant roots, lengthening phyllochrons. We hope that this area will become the focus of extensive research.

 

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15. Are There Significant Problems of Disadoption?

 

One of the first published reports on SRI in Madagascar (Moser and Barnett, 2003) reported that there was a high rate of disadoption of SRI methods, as much as 40%, after farmers tried out the methods, mostly because of the greater requirement of labor inputs with SRI. It was reported that even (especially) very poor farm households, which need continuous income to survive, said they could not afford to practice SRI, even though they knew that the methods would give higher yield. This article, based on well-designed and well-conducted field research, established the idea that SRI is ‘too labor intensive’ and is often given up by farmers after they try it.

 

As seen above, there is systematic evidence that SRI is labor-neutral or labor-saving rather than being necessarily labor-intensive. There is other evidence from Madagascar which suggests that disadoption is not a big problem in that country. This comes from an evaluation of a large French-funded irrigation project on the High Plateau (Hirsch, 2000) that was concurrent with the USAID project in Ranomafana that got CIIFAD involved with SRI. Around Ranomafana, farmers using SRI methods had average yields of 8 t/ha compared to 2 t/ha average on the same fields with conventional methods. The French project reported similar results as in Ranomafana. Comparisons were made with farmer practice and with ‘SRA’ stands for Systeme de Riziculture Ameliorée (System of Improved Rice Production), which required use of fertilizer, row planting, etc., ‘modern’ practices recommended by government scientists.

 

RICE YIELDS ON HIGH PLATEAU IN MADAGASCAR, 1994/5-1998/9

ANTSIRABE & AMBOSITRA REGIONS

 

PEASANT

 

 

 

AREA

Practice

SRA *

SRI
1994 / 95 1875.5 4361.9 34.5
1995 / 96 1501.5 5224.5 88.7
1996 / 97 1419.0 3296.7 226.7
1997 / 98 3122.0 2893.0 229.7
1998 / 99 2768.1 2628.0 542.8

YIELD

      
1994 / 95 2.02 3.96 8.62
1995 / 96 1.96 3.41 7.89
1996 / 97 2.08 3.30 10.68
1997 / 98 2.84 3.78 8.59
1998 / 99 2.97 4.61 8.07
AVERAGE 2.36 3.77 8.55

                                   

There is little indication of disadoption in these data, which came from a program where there was little organized effort to promote SRI. As of 2005, according to the Minister of Agriculture, over 200,000 farmers were using SRI methods in Madagascar (personal communication).

 

Disadoption has not been reported as a noticeable problem elsewhere except in Andhra Pradesh state of India. While there are no systematic data on disadoption there, the most common reason reported for stopping use of SRI methods is unreliability of electricity supply. This is a deterrent to adopting SRI and to continuing with it in Andhra Pradesh, since electricity is the main source of power for the pumps that provide fields with irrigation water. This is not a shortcoming of SRI itself, but of the infrastructure serving rice farmers. It reflects not the agronomics of SRI but the pragmatics of using its methods.

 

SRI use has dramatically increased in the Indian state of Tripura, as seen below. After a slow start, adjusting recommendations to local conditions, the state government decided in 2005 to give its full backing to SRI dissemination. One-third of the state’s agriculture sector budget was allocated to this purpose. For report, see : http://www.indiatogether.org/2008/jan/agr-sritrip.htm The head of the SRI extension effort in Tripura, Dr. Baharul Majumdar, senior agronomist with the Department of Agriculture, says that he has not heard of any Tripura farmers disadopting SRI methods once these have been tried.

 

SRI SPREAD IN THE INDIAN STATE OF TRIPURA, 2002-03 to 2007-08

  • 2002-03        -    44 farmers

  • 2003-04        -    88 farmers

  • 2004-05        -    440 farmers

  • 2005-06        -    880 farmers

  • 2006-07        -    73,390 farmers

  • 2007-08        -    162,485  farmers

(Source : Department of Agriculture, Agartala, Tripura)

 

In Cambodia, introduction of SRI started in 2000 with 28 farmers, encouraged and supported by the NGO CEDAC. By 2008, this number had increased to over 100,000 farmers. In 2007, CEDAC conducted an in-depth evaluation of SRI adoption and non-adoption in a sample of 21 villages in three districts where SRI had been available for at least five years. The survey team interviewed 348 adopters and 292 non-adopters in the 21 villages. The study determined that 46% of the households in these villages are using SRI methods, with demonstrably good results.

 

Of relevance here, the survey determined that the average number of disadopting households, ones which tried SRI methods and had given them up, was only 1 per village -- out of 200 households (CEDAC, 2008). So in Cambodia, where there is extensive experience with SRI, we have found a negligible rate of disadoption in rice-growing areas -- about half of one percent..

 

The CEDAC evaluation was useful in identifying that within the SRI system of management, certain methods have not been adopted or were disadopted because farmers found them difficult, such as frequent soil-aerating weeding. This study will focus CEDAC efforts on making further refinements in its extension strategy. It explains why SRI yields achieved on average have been lower than we know can be obtained with SRI methods on farmers’ fields. With regard to disadoption, the results confirm the observations from other countries that once SRI practices have been learned and used, not many farmers give up this new approach to rice production.

 

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16. How Has SRI Been Disseminated within and among Countries?
 

SRI is a civil society innovation that did not originate through the usual channels of agricultural scientific research. Rather, it was assembled through decades of work by Fr. de Laulanié, seeking to find simple, low-cost, accessible ways for farmers to increase the productivity of their land, labor, water and capital when growing irrigated rice. The beneficial insights that Laulanié gained from working with rice plants and farmers, and the methods that he consequently put together, can be extended to unirrigated rice production and to growing other crops. Clearly, SRI is not a typical ‘technology’ that can or should be extended in the way that most agricultural innovations have been spread in recent decades.

 

There was initially little interest in SRI from government personnel in Madagascar or from the International Rice Research Institute (IRRI) representatives in the country, so responsibility for further evaluation and dissemination of SRI fell first to  the NGO that Laulanié and several of his Malagasy colleagues established in 1990, Association Tefy Saina (http://www.tefysaina.org/). . This NGO was linked with a variety of other NGOs, church groups, and interested individuals. Starting in 1994, Tefy Saina began working with the Cornell International Institute for Food, Agriculture and Development (CIIFAD) (http://ciifad.cornell.edu) and then in 1998 with faculty and students at the University of Antananarivo. In 1999, a small grant was received from the Rockefeller Foundation for SRI evaluation by a consortium involving Tefy Saina and university partners with a researcher from the government’s agricultural research organization (FOFIFA). Such multi-sectoral collaboration has been typical of the way that SRI has been spread ever since.

 

Since there was no funding or project support from donor agencies or foundations in general, CIIFAD in collaboration with Tefy Saina has maintained an SRI website that has served to disseminate information on SRI around the world (http://ciifad.cornell.edu/sri/). NGOs that support low-input sustainable agriculture such as LEISA and ECHO have assisted this process by publishing articles on SRI, e.g., Rabenandrasana (1999), Berkelaar (2002).

 

Representatives of Tefy Saina and CIIFAD and increasingly partners in the various countries, have spoken at international and national forums and seminars on SRI such as:

  • an NGO forum on rice in the Philippines (1998);

  • an Agronomy Society of America/World Bank workshop on sustainable agriculture in Baltimore (2000);

  • a sustainable agriculture conference at St. James Palace in London (2001);

  • an international conference on sustainable agriculture and natural resource management at Chiangmai, Thailand (2002);

  • International Rice Congresses in Beijing (2002) and New Delhi (2006); 

  • Latin American regional rice meetings in Cuba (2002, 2003 and 2008);

  • the World Rice Research Congress at Tsukuba, Japan (2004);

  • an International Farming Systems Association conference in Orlando, FL (2004);

  • FAO’s International Rice Commission meeting in Chiclayo, Peru (2006); and

  • 13th meeting of the U.N. Commission on Sustainable Development in NYC (2008) and the UNCSD inter-sessional meeting in Namibia and its preparatory meeting in NYC (2009).

Country by country, persons have come forward with an interest in raising productivity and incomes for rice farmers and in doing this with protection/enhancement of the environment.

 

The backgrounds of these persons have been diverse: a retired agricultural economics professor in Bangladesh; the agronomics-trained leader of an NGO in Cambodia; a number of senior rice scientists in China; a retired animal nutritionist in Cuba; an agricultural research station director in The Gambia; the director of extension for a state agricultural university in India; a private-sector consulting team leader from Japan in Indonesia; a district agricultural extensionist in Nepal; the director-general for water management in Pakistan; a private consultant in Peru; an electrical-engineer head of an environmental NGO in the Philippines; a senior civil servant, a farmer-environmental activist, and a deputy minister of agriculture in Sri Lanka; an NGO activist in Zambia; a German aid agency staff member in Timor Leste; and so it goes.

 

A number of SRI colleagues have travelled to other countries to help transfer SRI knowledge:  from Sri Lanka to India; from India and Myanmar to Afghanistan; from China to North Korea; from Madagascar to Rwanda; from Indonesia to Malaysia; from Cambodia to Vietnam; from India to Morocco. Colleagues in a number of countries have hosted visits from other countries to share SRI knowledge: Madagascar (Indonesia and Sierra Leone); Sri Lanka (India and Pakistan); India (Bangladesh); Cambodia (Vietnam). Norman Uphoff, former director of CIIFAD, who has more opportunity to travel than most persons, have made presentations on SRI in >35 countries.

 

Leadership for SRI evaluation and dissemination in any country, state or district can come from any sector: from government, NGO, university, private-sector, or farmer organizations. But in each country, there usually emerges a cooperative network of like-minded persons from these different sectors who each contribute to the advance of SRI understanding and practice according to their respective, comparative advantages.

 

Once SRI is introduced and demonstrated, we have seen various donor agencies and international NGOs begin to support SRI extension: GTZ in Cambodia; World Vision and USAID in Sierra Leone; ADRA in Madagascar and Indonesia; Oxfam-America in Cambodia and Vietnam; Oxfam-Australia in Sri Lanka and Laos; Oxfam-Great Britain in Bangladesh; Oxfam-Quebec in Vietnam; ActionAid in Bangladesh; the World Bank in Tamil Nadu state of India; the Medco Foundation in Indonesia; the BetterU Foundation in Mali; and so forth. A few private individuals have also given financial support for SRI’s spread, and the Rockefeller Foundation and the World Bank helped to fund the first international SRI conference, held in China in 2002. In a number of countries, farmers have emerged as SRI spokespersons and trainers, giving of their own time and money to promote SRI practices to hundreds, even thousands of fellow farmers. The extension of SRI has thus had extremely diverse support, notable for its voluntary nature. Cornell’s support for the overall communication and exchanges has come from CIIFAD and individual contributions of time and money.

 

Relative to the limited amount of institutional and financial support that this far-flung, voluntaristic SRI campaign has received, the amount of impact that it has already achieved is unprecedented. But then so is SRI as an innovation. It is possible that this SRI experience will open up new styles and roles for agricultural extension and development, with farmers not regarded as ‘adopters’ or as ‘recipients’ of scientific and technological advice - but rather as ‘partners’ and ‘innovators’ in the process of SRI adaptation and further evolution. Farmers, by themselves or in cooperation with NGO, government or other partners, have been making substantial improvement in SRI, particularly to reduce its labor requirements. This stems from treating SRI not as a ‘technology’ that is finished and fixed but always as a work in progress.

 

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17. What Has Been the Response of Scientists and Policy Makers?

 

Usually in the 20th century, technological improvements followed from advances made in scientific knowledge. With SRI, on the other hand -- as with the invention of the airplane - new technology has preceded the science that could explain it. The civil-society movement that has propelled SRI has had endorsements from some eminent rice scientists, including Dr. M.S. Swaminanathan, hailed as ‘the father of the Green Revolution’ in India and a former director-general of IRRI, and Prof. Yuan Long-ping, known as ‘the father of hybrid rice’ in China and around the world (Yuan, 2002). These and other scientists have participated together with NGOs, farmers, officials and others in the progress of SRI. Possibly the SRI experience will break new ground encouraging more broad-based approaches to scientific and technological progress.

 

When Fr. de Laulanié first introduced SRI to scientists at the University of Antananarivo and in the Ministry of Agriculture in 1990, there was disbelief and derision. In 1993, when Prof. Uphoff of CIIFAD first learned about SRI and asked the IRRI representative in Madagascar whether IRRI had done any evaluations of SRI, he said that the Malagasy scientists who had evaluated SRI had not been able to replicate the very high yields reported by the priest, 10-15 t/ha. What yields had they gotten? Uphoff asked. Only 5-7 t/ha, as the reply, and given that IRRI could obtain such with its improved varieties and methods, this made SRI of little interest to IRRI.

 

At that time, Uphoff was not himself persuaded about SRI merits, so he did not ask the obvious question: If Madagascar farmers who now average 2 t/ha can get 5-7 t/ha just by changing the way they use the resources that they now have, not needing to purchase new seeds or chemical fertilizer, couldn’t this have a big impact on reducing hunger and poverty?  Most farmers in Madagascar were not using ‘modern’ rice technology because they were too poor or had no reliable access to inputs.  The scientific consensus was that SRI was ‘not interesting,’ however, so it was simply ignored. This attitude was also evident among most agronomists at Cornell University and elsewhere in the developed world -- with a few noteworthy exceptions.

 

In 1998, Uphoff talked about SRI with the newly-appointed Director-General of IRRI, Dr. Ron Cantrell. The conversation was cordial, but after Uphoff gave a seminar on SRI at IRRI in February, 1999, there was no expression of interest in cooperation. In 2001, Cantrell informed Uphoff that he would have no further communication regarding SRI. After Uphoff gave another seminar at IRRI in March 2003, several scientists working with IRRI began publishing critiques (e.g., Dobermann, 2004; Sheehy et al., 2004; Sinclair and Cassman, 2004; Sinclair, 2004).

 

Fortunately, scientists in national agricultural research institutions have been more receptive to SRI’s new ideas and have been willing to evaluate the new methods, establishing the scientific foundations for SRI. This process started in 1999 with evaluations done at Nanjing Agricultural University in China and the Agency for Agricultural Research and Development in Indonesia. Further evaluations were done by scientists at the China National Hybrid Rice Research and Development Center (CNHRRDC) and the China National Rice Research Institute (CNRRI).

 

Already starting in 1998, top students in the Faculty of Agriculture (ESSA) at the University of Antananarivo in Madagascar began doing thesis research under the late Prof. Robert Randriamiharisoa. Factorial trials clearly showed the merits of SRI practices respectively and collectively (Randrimiharisoa and Uphoff, 2002).

 

In India, evaluations of SRI began at Tamil Nadu Agricultural University in 2000, and with support from the World Wide Fund for Nature (WWF) through its joint program with ICRISAT on food, water and environment, a collaborative evaluation began in 2004. This involved scientists at the state agricultural university in Andhra Pradesh (ANGRAU), the Directorate of Rice Research (DRR) of the Indian Council for Agricultural Research (ICAR), and ICRISAT, all based in Hyderabad. The Indian Ministry of Agriculture’s Directorate of Rice Development (DRD) in Patna also did its own evaluations in this period and became supportive of SRI based on results. In 2007, the Government of India allocated $40 million for dissemination of SRI to >130 food-insecure districts under its National Food Security Mission with the endorsement of the Ministry of Agriculture and ICAR.

 

The national rice research centers in Iraq and Iran, at Najaf and Amol, respectively, began their own evaluations in 2005 and demonstrated the benefits of SRI practices to the satisfaction of their scientists (see Iraq and Iran country pages on SRI website: http://ciifad.cornell.edu/sri/). There was, however, still some resistance in certain countries’s rice science circles, such as Sri Lanka, Bangladesh and Cambodia, influenced by the criticisms from international rice scientists. Over time, however, even this scientific opinion has become more favorable toward SRI, given that the national rice research systems in the three major rice-producing countries, China, India and Indonesia, where over 60% of the world’s rice is produced, have become supportive of SRI.

 

Currently, there is joint evaluation of SRI being planned by researchers from IRRI, Cornell University and Wageningen University, which will follow agreed-upon protocols in at least three countries with differing agroecological conditions. The results of this evaluation should resolve for any objective scientist any remaining issues or uncertainties about SRI’s validity. Because these results will not be officially known until 2011, however, for some persons, the controversy will not be resolved for another three years.

 

Meanwhile, more and more Master’s and PhD theses are being done on SRI at universities around the world; more and more articles are being published on SRI in peer-reviewed journals, establishing a more thorough understanding of how and why SRI’s innovative practices produce the effects reported here (e.g., Horie et al., 2005: Mishra et al., 2006; Mishra and Salokhe, 2008). SRI represents a paradigm shift, from agricultural advances based on genetic improvements and application of external inputs, to increasing productivity through alternative management practices that promote root growth and stimulate beneficial activity from the soil biota.

 

Paradigm shifts seldom come smoothly, even (especially?) in the realm of science. In the case of SRI, the shift may come more quickly and certainly because the validity of the new ways of thinking will not be decided just by inner and outer circles of scientists, but by the actions and assessments of millions of farmers, eventually hundreds of millions. When they give SRI a vote of confidence by their use and continuation of the methods, any dismissals and disparagements in the peer-reviewed literature will carry little weight, even among most scientists. The open question is whether the paradigm shift will be limited to rice production or will have ramifications for agricultural science and practice more generally as we seek better pathways to food security and prosperity in the 21st century with its challenges land and water limitations, rising costs of energy, climate change, environmental degradation, and immense human needs.

 

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