Sunday, February 17, 2013

A shared perspective... Nature ever ready to show its intelligence and grace... we have only to recognize its calling...

Following is a quote from the posted article relating to a farming practice that has proved to be exceedingly effective. As I read the article (posted below) it became evident that the principles and practices put forth,  bringing on such positive results,  were clearly allied to the very principles of education upon which APOGEE Learning™ has been developed. There was that 'ah-ha-moment'  of realization that gave meaning to interconnections,  to synergy, to corresponding worlds. I encourage your perusal of both the article and APOGEE Learning™. Nature calls for its nurture as do our growing children. Principles of growth, development and sustainability apply to all living matter, be it of animals, of plants, of our environment, or of the human condition.

"Scientists should avoid becoming prisoners of their present knowledge, captives of prevailing paradigms. Paradigms are needed to make sense of the world and to be able to act upon it. But they are constructs made by human beings, not true in themselves. Anyone who seriously follows scientific principles knows that while theory is necessary to organize knowledge and to test it, the ultimate tests are always empirical, not logical. While quantum physics is the most powerful body of scientific theory in the world today, its strength lies not in its logic -- it is quite illogical in many ways -- but in its repeated verification by empirical results.."


DEVELOPMENT OF THE SYSTEM OF RICE INTENSIFICATION (SRI) IN MADAGASCAR by  Norman Uphoff, Cornell University  ( article follows)  Uphoff, N. 2003. Higher yields with fewer external inputs? The System of Rice Intensification and potential contributions to agricultural sustainability. International Journal of Agricultural Sustainability, 1, 38-50.
 Article republished from by  in Bihar, India,The Observer, Saturday 16 February 2013 

Sumant Kumar was overjoyed when he harvested his rice last year. There had been good rains in his village of Darveshpura in north-eastIndia and he knew he could improve on the four or five tonnes per hectare that he usually managed. But every stalk he cut on his paddy field near the bank of the Sakri river seemed to weigh heavier than usual, every grain of rice was bigger and when his crop was weighed on the old village scales, even Kumar was shocked. SRI’s origins go back to the 1980s in Madagascar where Henri de Laulanie, a French Jesuit priest and agronomist, observed how villagers grew rice in the uplands. He developed the method but it was an American, professor Norman Uphoff, director of the International Institute for Food, Agriculture and Development at Cornell University, who was largely responsible for spreading the word about De Laulanie’s work.
This was not six or even 10 or 20 tonnes. Kumar, a shy young farmer in Nalanda district of India’s poorest state Bihar, had – using only farmyard manure and without any herbicides – grown an astonishing 22.4 tonnes of rice on one hectare of land. This was a world record and with rice the staple food of more than half the world’s population of seven billion, big news.
It beat not just the 19.4 tonnes achieved by the “father of rice”, the Chinese agricultural scientist Yuan Longping, but the World Bank-funded scientists at the International Rice Research Institute in the Philippines, and anything achieved by the biggest European and American seed and GM companies. And it was not just Sumant Kumar. Krishna, Nitish, Sanjay and Bijay, his friends and rivals in Darveshpura, all recorded over 17 tonnes, and many others in the villages around claimed to have more than doubled their usual yields.
The villagers, at the mercy of erratic weather and used to going without food in bad years, celebrated. But the Bihar state agricultural universities didn’t believe them at first, while India’s leading rice scientists muttered about freak results. The Nalanda farmers were accused of cheating. Only when the state’s head of agriculture, a rice farmer himself, came to the village with his own men and personally verified Sumant’s crop, was the record confirmed.
The rhythm of Nalanda village life was shattered. Here bullocks still pull ploughs as they have always done, their dung is still dried on the walls of houses and used to cook food. Electricity has still not reached most people. Sumant became a local hero, mentioned in the Indian parliament and asked to attend conferences. The state’s chief minister came to Darveshpura to congratulate him, and the village was rewarded with electric power, a bank and a new concrete bridge.
That might have been the end of the story had Sumant’s friend Nitish not smashed the world record for growing potatoes six months later. Shortly after Ravindra Kumar, a small farmer from a nearby Bihari village, broke the Indian record for growing wheat. Darveshpura became known as India’s “miracle village”, Nalanda became famous and teams of scientists, development groups, farmers, civil servants and politicians all descended to discover its secret.
When I meet the young farmers, all in their early 30s, they still seem slightly dazed by their fame. They’ve become unlikely heroes in a state where nearly half the families live below the Indian poverty line and 93% of the 100 million population depend on growing rice and potatoes. Nitish Kumar speaks quietly of his success and says he is determined to improve on the record. “In previous years, farming has not been very profitable,” he says. “Now I realise that it can be. My whole life has changed. I can send my children to school and spend more on health. My income has increased a lot.”
What happened in Darveshpura has divided scientists and is exciting governments and development experts. Tests on the soil show it is particularly rich in silicon but the reason for the “super yields” is entirely down to a method of growing crops called System of Root Intensification (SRI). It has dramatically increased yields with wheat, potatoes, sugar cane, yams, tomatoes, garlic, aubergine and many other crops and is being hailed as one of the most significant developments of the past 50 years for the world’s 500 million small-scale farmers and the two billion people who depend on them.
Instead of planting three-week-old rice seedlings in clumps of three or four in waterlogged fields, as rice farmers around the world traditionally do, the Darveshpura farmers carefully nurture only half as many seeds, and then transplant the young plants into fields, one by one, when much younger. Additionally, they space them at 25cm intervals in a grid pattern, keep the soil much drier and carefully weed around the plants to allow air to their roots. The premise that “less is more” was taught by Rajiv Kumar, a young Bihar state government extension worker who had been trained in turn by Anil Verma of Professional Assistance for Development Action, an Indian NGO which has introduced the SRI method to hundreds of villages in the past three years.
While the “green revolution” that averted Indian famine in the 1970s relied on improved crop varieties, expensive pesticides and chemical fertilisers, SRI appears to offer a long-term, sustainable future for no extra cost. With more than one in seven of the global population going hungry and demand for rice expected to outstrip supply within 20 years, it appears to offer real hope. Even a 30% increase in the yields of the world’s small farmers would go a long way to alleviating poverty.
“Farmers use less seeds, less water and less chemicals but they get more without having to invest more. This is revolutionary,” said Dr Surendra Chaurassa from Bihar’s agriculture ministry. “I did not believe it to start with, but now I think it can potentially change the way everyone farms. I would want every state to promote it. If we get 30-40% increase in yields, that is more than enough to recommend it.”
The results in Bihar have exceeded Chaurassa’s hopes. Sudama Mahto, an agriculture officer in Nalanda, says a small investment in training a few hundred people to teach SRI methods has resulted in a 45% increase in the region’s yields. Veerapandi Arumugam, the former agriculture minister of Tamil Nadu state, hailed the system as “revolutionising” farming.
SRI’s origins go back to the 1980s in Madagascar where Henri de Laulanie, a French Jesuit priest and agronomist, observed how villagers grew rice in the uplands. He developed the method but it was an American, professor Norman Uphoff, director of the International Institute for Food, Agriculture and Development at Cornell University, who was largely responsible for spreading the word about De Laulanie’s work.
Given $15m by an anonymous billionaire to research sustainable development, Uphoff went to Madagascar in 1983 and saw the success of SRI for himself: farmers whose previous yields averaged two tonnes per hectare were harvesting eight tonnes. In 1997 he started to actively promote SRI in Asia, where more than 600 million people are malnourished.
“It is a set of ideas, the absolute opposite to the first green revolution [of the 60s] which said that you had to change the genes and the soil nutrients to improve yields. That came at a tremendous ecological cost,” says Uphoff. “Agriculture in the 21st century must be practised differently. Land and water resources are becoming scarcer, of poorer quality, or less reliable. Climatic conditions are in many places more adverse. SRI offers millions of disadvantaged households far better opportunities. Nobody is benefiting from this except the farmers; there are no patents, royalties or licensing fees.” For 40 years now, says Uphoff, science has been obsessed with improving seeds and using artificial fertilisers: “It’s been genes, genes, genes. There has never been talk of managing crops. Corporations say ‘we will breed you a better plant’ and breeders work hard to get 5-10% increase in yields. We have tried to make agriculture an industrial enterprise and have forgotten its biological roots.”
Not everyone agrees. Some scientists complain there is not enough peer-reviewed evidence around SRI and that it is impossible to get such returns. “SRI is a set of management practices and nothing else, many of which have been known for a long time and are best recommended practice,” says Achim Dobermann, deputy director for research at the International Rice Research Institute. “Scientifically speaking I don’t believe there is any miracle. When people independently have evaluated SRI principles then the result has usually been quite different from what has been reported on farm evaluations conducted by NGOs and others who are promoting it. Most scientists have had difficulty replicating the observations.”
Dominic Glover, a British researcher working with Wageningen University in the Netherlands, has spent years analysing the introduction of GM crops in developing countries. He is now following how SRI is being adopted in India and believes there has been a “turf war”.
“There are experts in their fields defending their knowledge,” he says. “But in many areas, growers have tried SRI methods and abandoned them. People are unwilling to investigate this. SRI is good for small farmers who rely on their own families for labour, but not necessarily for larger operations. Rather than any magical theory, it is good husbandry, skill and attention which results in the super yields. Clearly in certain circumstances, it is an efficient resource for farmers. But it is labour intensive and nobody has come up with the technology to transplant single seedlings yet.”
But some larger farmers in Bihar say it is not labour intensive and can actually reduce time spent in fields. “When a farmer does SRI the first time, yes it is more labour intensive,” says Santosh Kumar, who grows 15 hectares of rice and vegetables in Nalanda. “Then it gets easier and new innovations are taking place now.”
In its early days, SRI was dismissed or vilified by donors and scientists but in the past few years it has gained credibility. Uphoff estimates there are now 4-5 million farmers using SRI worldwide, with governments in China, India, Indonesia, Cambodia, Sri Lanka and Vietnam promoting it.
Sumant, Nitish and as many as 100,000 other SRI farmers in Bihar are now preparing their next rice crop. It’s back-breaking work transplanting the young rice shoots from the nursery beds to the paddy fields but buoyed by recognition and results, their confidence and optimism in the future is sky high.
Last month Nobel prize-winning economist Joseph Stiglitz visited Nalanda district and recognised the potential of this kind of organic farming, telling the villagers they were “better than scientists”. “It was amazing to see their success in organic farming,” said Stiglitz, who called for more research. “Agriculture scientists from across the world should visit and learn and be inspired by them.” Bihar, from being India’s poorest state, is now at the centre of what is being called a “new green grassroots revolution” with farming villages, research groups and NGOs all beginning to experiment with different crops using SRI. The state will invest $50m in SRI next year but western governments and foundations are holding back, preferring to invest in hi-tech research. The agronomist Anil Verma does not understand why: “The farmers know SRI works, but help is needed to train them. We know it works differently in different soils but the principles are solid,” he says. “The biggest problem we have is that people want to do it but we do not have enough trainers.
“If any scientist or a company came up with a technology that almost guaranteed a 50% increase in yields at no extra cost they would get a Nobel prize. But when young Biharian farmers do that they get nothing. I only want to see the poor farmers have enough to eat.”
—————————————————————————————————————————————————–DEVELOPMENT OF THE SYSTEM OF RICE INTENSIFICATION (SRI) IN MADAGASCAR by  Norman Uphoff, Cornell University-  The development of the System of Rice Intensification (SRI) 20 years ago in Madagascar by Fr. Henri de Laulanié, S.J. — based on 20 years before that of working with farmers to improve their rice production without dependence on external inputs — is a most unusual case. It is unusual partly because SRI is one of the most remarkable agricultural innovations of the last century, one only starting to be appreciated in this one. But it is also unusual because of the resistance, sometimes vehement, that it has encountered from the scientific community despite the evident benefits that it offered particularly for poor farmers and for the environment: doubling yields or even more without requiring the use of fertilizer or other chemical inputs, and using less water. This case suggests a lesson for scientists as well as for extension personnel and farmers — for all to be open to new ideas, no matter what their source. Not every proposed change in agricultural practices warrants much attention; but if a possible innovation would have many benefits, it should be subjected to empirical rather than just logical tests, because our scientific knowledge is not (and never will be) perfect or complete. In the SRI case, a paradigm shift was involved, one that is not yet fully understood and certainly not universally accepted. Typical positivist approaches for testing and validating new knowledge were not applicable because larger issues were at stake, one not amenable to either proof or disproof just by hypothesis testing.
The case is instructive also because it goes against the now popular view that farmer knowledge, being based on generations of trial-and-error and subsequent validation, is a superior source of information and insights about how to practice agriculture. SRI changes dramatically four practices that farmers growing irrigated rice have used for centuries, even millennia. Part of the resistance came from the innovation’s being so counter-intuitive: where smaller would become bigger, and less could produce more. This sounds like nonsense; but it is possible and true.
The Challenge- When Henri de Laulanié was assigned by the Jesuit order to move from France to Madagascar in 1961, the first thing he saw around him was the great poverty and hunger of most of the people, one of the poorest populations in the world. He saw also their deteriorating natural resource base, with drastic soil erosion and accelerating deforestation, these two processes being connected.
Laulanié concluded, apparently, that raising the yields of rice, the staple food providing more than half of the daily calories of Malagsy households, was the greatest contribution he could make to the well-being of the people around him. It was also essential if continuing destruction of the precious tropical rain forest ecosystems was to be halted. Laulanié had done a degree in agriculture at the best university in France (now known as Paris- Grignon) before entering the seminar in 1941, so he knew basic agricultural science if not much about tropical rice. There were few scientific resources to draw on in immediately post-colonial Madagascar, in libraries or in research institutes, so he started working directly with farmers, carefully observing their practices, asking questions, trying things out on his own paddy plot.
Assembling the Innovation- Laulanié found a few farmers not transplanting rice seedlings in clumps of three, four, five or more, as farmers all around the world choose to do, instead planting individual seedlings. These farmers in the minority found that single seedlings produced as well or better than clumps of plants, and this way they could reduce their seed costs, a consideration for very poor farmers. So he tried this himself, and found it was a good practice. Then, in another area he observed some farmers not keeping their paddy fields continuously flooded throughout the season, as is done around the world wherever farmers have access to enough water to do this. It is widely believed that rice plants fare best in saturated soil. But Laulanié found that they can grow even better if raised in soil that is kept moist but never continuously flooded. While rice plants can survive under flooded conditions, they do not thrive.
Having started to grow single seedlings in unflooded soil during their period of vegetative growth (i.e., up to flowering; after panicle initiation, he kept a thin layer of water, 1-2 cm, on the field), Laulanié next introduced a practice of his own. The government was promoting use of a simple mechanical hand weeder known as the ‘rotating hoe’ (houe rotative). This churned up the soil with small toothed wheels, burying weeds in the soil to decompose. It also aerated the soil in the process, though nobody considered this benefit at the time.
Laulanié decided to try planting seedlings in a square pattern, rather than in the rows being promoted by rice specialists. This way he could use the weeding in two directions, i.e., perpendicularly. He tried this with 25×25 cm spacing just to see what would happen. To his pleasant surprise, widely spaced rice plants, growing singly in moist but not flooded soil, did better than others grown with the common practices. At this point, the priest established a small school in Antsirabe to teach young farmers these new methods and to give them a basic education that prepared them for life rather than for further studies and white-collar employment. In 1983-84, a fortuitous accident occurred. Two weeks after planting the rice nursery, Laulanié had second thoughts and decided that they might need more seedlings for the field, so more were planted for what was likely to be a water-short season.
A good rain fell when the first set of seedlings was 30 days old. Because they were not sure whether any more good rain would follow, the teacher and his students decided to transplant all of the seedlings into their rice field, the tiny ones only 15 days old as well. They had few hopes or expectations for the spindly younger seedlings. Yet after a month, these began to surpass the older ones, and by the end of the season, their yield was much higher (Laulanié 1993).
Rather than pass this off as a fluke, the next year younger seedlings were planted again, and then even younger seedlings. By the end of the decade, it was clear to everyone at the school and to the farmers who visited it that using younger seedlings gave much better results, provided that they were planted singly and far apart, in a square pattern (even up to 50×50 cm when the soil quality had been built up by these practices) in soil both well aerated and moist during the plants’ growth period. They did not know that research had been published already showing that when rice plants are kept continuously flooded, up to 78% of their roots degenerate under the hypoxic conditions (Kar et al. 1974). The negative effect of continuous soil saturation on roots’ growth and functioning was being overlooked by both scientists and farmers alike.
SRI was developed initially with the use of chemical fertilizers, because everyone believed that this was necessary to increase yields, especially on Madagascar soils that were mostly ‘poor’ as evaluated by standard chemical tests. When the government removed its subsidies for fertilizer in the late 1980s, and poor farmers could no longer afford to use it, Laulanié and his students began working with compost. In most instances, this gave even better rice yields when used with the other practices.
Proceeding with the Innovation- In 1990, Laulanié and several of his close Malagasy friends established an NGO, Association Tefy Saina, to promote SRI and rural development generally. The NGO name, in Malagasy, means ‘to improve the mind,’ because they saw SRI as not just a means to improve rice production and meet food and income needs. It was thought that SRI’s spectacular results could open farmers’ minds to further innovation beyond rice cultivation because they came from changing practices that had been used for generations by farmers’ ancestors, greatly venerated in traditional culture and beliefs. For the priest and his friends, human development and spiritual growth were considered more important than agricultural improvement alone.
In part because SRI was not seen and treated in narrowly technical terms, it was scoffed at and rejected by Malagasy and international scientists who learned about it, though a few European NGOs gave Tefy Saina some small grants for training in the early 1990s. In 1994, CIIFAD, the Cornell International Institute for Food, Agriculture and Development, began working with Tefy Saina to introduce SRI to farmers in the peripheral zone around Ranomafana National Park. This was one of the last remaining large blocks of rain forest, under serious threat from the slash-and- burn cultivation of upland rice.
Farmers around Ranomafana were getting lowland rice yields of only 2 t/ha from their small areas having irrigation. To feed their families, they needed to practice upland cultivation. Raising lowland yields was thus seen as a requirement for saving the rain forest, as well as for reducing poverty. In 1994-95, only 38 farmers would try the new methods, which changed four things that had been done from time immemorial in Madagascar, and in most other rice-growing countries:
  • Instead of planting seedlings 30-60 days old, tiny seedlings less than 15 days old were planted.
  • Instead of planting 3-5 or more seedlings in clumps, single seedlings were planted instead
  • of close, dense planting, with seed rates of 50-100 kg/ha, plants were set out carefully 
and gently in a square pattern, 25x25cm or wider if the soil was very good; the seed rate was reduced by 80-90%, netting farmers as much as 100 kg of rice per hectare.Instead of keeping rice paddies continuously flooded, only a minimum of water was applied daily to keep the soil moist, not always saturated; fields were allowed to dry out several times to the cracking point during the growing period, with much less total use of water.
Why hadn’t farmers tried these new practices before? All looked very risky, and even a little crazy. Why should tiny young plants perform better than larger ones? Why should fewer plants give more yield than more plants? Why should plants not be kept flooded if water was available? Water was thought to be like fertilizer, and rice was regarded as a water-loving plant. The chance that a farmer would ever try all four of these practices together, and risk the scorn of his neighbors as well as the wrath of his ancestors, was infinitesimal.
The farmers around Ranomafana who used SRI in 1994-95 averaged over 8 t/ha, more than four times their previous yield, and some farmers reached 12 t/ha and one even got 14 t/ha. The next year and the following year, the average remained over 8 t/ha, and a few farmers even reached 16 t/ha, beyond what scientists considered to be ‘the biological maximum’ for rice. But these calculations were based on rice plants that had degenerated and truncated root systems.
Understanding the Innovation- How could such remarkable results be obtained? There is demonstrable synergy among these practices, when used together, especially when the rotating hoe is used to control weeds — and aerate the soil frequently during the growth period. This has been documented by replicated multi-factorial trials (N=288 and N=240) in contrasting agroecological situations: tropical climate, poor sandy soils at sea level vs. temperate climate, better clay and loam soils at high elevation. These trials showed that when compost is added to the soil, increasing soil organic matter and nourishing soil microorganisms beyond what the plants’ own (greater) exudation can support, large increases, even a tripling in yield, can result. On poorer loam soil, SRI practices gave 6.39 t/ha compared to 2.04 t/ha with standard practice (mature seedlings, close spacing, continuous flooding, NPK fertilizer). On better clay soils, yields went from 3.0 with standard methods to 10.35 t/ha with SRI (Randriamiharisoa and Uphoff 2002).
With SRI methods, one could see, after the first month a much greater number of tillers, 30-50 per plant, with some plants producing even 80-100 tillers. If one pulled up SRI plants, one could see that they had much larger and deeper root systems. A pull test to measure the resistance that plant root systems give to uprooting found that it took 5-6 times more force (kg/plant) to do this for SRI plants. Having more roots can support more tiller growth and more grain filling, while plants having a larger canopy with more photosynthesis can support more root growth.
Scientifically, the most interesting phenotypic change was in the relationship between number of tillers/plant and number of grains/tiller (panicle). For SRI plants, this correlation was positive rather than negative, as is widely reported in the literature. With a larger root system, SRI plants can access both more soil nutrients, right through the ripening stage with less plant senescence, and a wider variety of nutrients, including micronutrients not provided by NPK fertilizer. SRI methods contribute to more grain production and also to a lower percentage of unfilled grains and to higher grain weight.
SRI achieves higher yields, sometime over 20 t/ha when soil conditions approach are optimal. It does not follow the two strategies that produced the gains of the Green Revolution: (a) changed and increased genetic potential, and (b) use of external inputs — more fertilizer, more water, more agrochemicals. SRI was hard at first to understand because it took such a different path.
Instead, SRI changes common practices for plant, soil, water and nutrient management so as to: (a) increase plant root growth and functioning, and (b) enhance the abundance and diversity of soil biota, from microorganisms (bacteria and fungi) through micro and meso-fauna (nematodes and protozoa) to macro fauna (particularly earthworms).
Spread of the Innovation- This case study cannot go more into the mechanisms and processes, which are still only partially documented and understood, but they are increasingly validated by SRI use in a growing number of countries around the world (see Stoop et al. 2002, and Uphoff 2003). Good SRI results have now been reported from countries ranging from China, through Indonesia, Philippines, Cambodia, Laos, Thailand and Myanmar, to Bangladesh, Sri Lanka, Nepal and India, to Madagascar, Benin, Gambia, Guinea and Sierra Leone, and now to Cuba and Peru.
The methods raise, concurrently, the productivity of land, labor, capital and water, without tradeoffs, something never seen before. SRI practices achieve different and more productive phenotypes from any genotype of rice by providing a better growing environment in which the plant can express its genetic potential. SRI is best understood as part of a growing movement in the agricultural sector toward what can be characterized as agroecological innovation. This strategy seeks to capitalize on synergies among species and organisms when these are provided with optimum growing conditions. Conventional agricultural practices, favoring monoculture, seek to maximize production of single species, one at a time, taking them out of the context of their natural environments, changing that environment by ploughing, fertilization, irrigation, etc.
What can be learned from this experience about participatory research and development?
  1. One should not assume that current farmer practices are always ideal or the best. They have been developed under certain conditions, constrained by knowledge and imagination as well as biophysical factors. Farmer knowledge is a good place to start, and should always be respected. But it should not be idealized. It was just a few ‘deviant’ farmers who contributed some of the novel ideas that made SRI possible.
  2. One should work closely with farmers in the development of any agricultural innovation. Fr. de Laulanié had a great and self-evident love for rural people, demonstrated throughout his 34 years living among them in Madagascar. He was devoted to helping them improve their productivity and welfare. He avidly learned from them. But he also formed his own opinions, always subjecting practices and ideas to empirical tests.
  3. Scientists should avoid becoming prisoners of their present knowledge, captives of prevailing paradigms. Paradigms are needed to make sense of the world and to be able to act upon it. But they are constructs made by human beings, not true in themselves. Anyone who seriously follows scientific principles knows that while theory is necessary to organize knowledge and to test it, the ultimate tests are always empirical, not logical. While quantum physics is the most powerful body of scientific theory in the world today, its strength lies not in its logic — it is quite illogical in many ways — but in its repeated verification by empirical results.
  4. There has been a lot of effort going into systematizing the processes of participatory research and development, e.g., through participatory action research and participatory rural appraisal (PRA). As recent reflections on PRA show, it is important not to let techniques and processes become rigidified and routinized because then means become ends in themselves (Cornwall and Pratt 2003). Fr. de Laulanié worked with great originality and dedication. He had respect for science, having been trained in it, but particularly for farmers and for empirical truth. He improvised the whole process by which SRI was developed.
5 If Father de Laulanié had been guided (and constrained) by a lot of preconceptions, it is unlikely that he could have discovered anything as unique and powerful as SRI, breaking with ages-old practices to ‘liberate’ genetic potentials that have existed in rice plants for millennia. We must never let form triumph over substance and over vision and imagination.
For more information on SRI, see the SRI home page: — or communicate with Tefy Saina ( or the author (
Cornwall, A. and G. Pratt. 2003. Pathways to Participatiohn: Reflections on Participatory Rural Appraisal. London: Intermediate Technology Development Group Publishing.
Kar, S., S., Varade, T. Subramanyam, and B. P. Ghildyal. 1974. Nature and growth pattern of rice root system under submerged and unsaturated conditions. Il Riso (Italy) 23, 173-179.
Laulanié, H. de. 1983. Le système de riziculture intensive malgache. Tropicultura (Brussels) 11, 110-114.
Randriamiharisoa, R. and N. Uphoff. 2002. Factorial trials evaluating the separate and combined effects of SRI practices. In: The System of Rice Intensification: Proceedings of an international conference, Sanya, China, April 1-4, 2002. Ithaca, NY: Cornell International Institute for Food, Agriculture and Development.
Stoop, W., N. Uphoff, and A. Kassam. 2002. A review of agricultural research issues raised by the System of Rice Intensification (SRI) from Madagascar: Opportunities for improving farming systems for resource-poor farmers. Agricultural Systems 71, 249-274.
Uphoff, N. 2003. Higher yields with fewer external inputs? The System of Rice Intensification and potential contributions to agricultural sustainability. International Journal of Agricultural Sustainability, 1, 38-50.

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