Rice, the staple food crop for more than half the worlds
population, among them the poorest, is the current target of genetic
modification, an activity that has greatly intensified after the rice genome
was announced two years ago (see "Rice is life" series,
SiS 15, Summer 2002).
Since then, all major biotech giants are investing in rice research.
At the same time, a low-input cultivation system that really benefits
small farmers worldwide has been spreading, but is dismissed by the scientific
establishment as "unscientific". This is one among several recent innovations
that increase yields and ward off disease without costly and harmful inputs,
all enthusiastically and widely adopted by farmers.
A war is building up between the corporate establishment and the peoples
of the world for the possession of rice. The food security of billions is at
stake, as is their right to grow the varieties of rice they have created and
continue to create, and in the manner they choose.
This extended series will not be appearing all at once, so look out for
Fantastic Rice Yields Fact or Fallacy?
Top Indian Rice Geneticist Rebuts SRI critics
Does SRI work?
Corporate Patents vs People in GM Rice
Promises and Perils of GM Rice
Two Rice Better Than One
One Bird - Ten Thousand Treasures
New Rice For Africa
ISIS Report 06/07/04
Does SRI Work?
The first reality check of a low-input rice-growing system took place
two years ago and more successes documented since.
Dr. Mae-Wan Ho reports
for this report are available in the ISIS members site.
Full details here
The clearest sign that SRI works, if not miracles, then certainly well
enough, is the number of participants drawn to the first in-depth international
assessment of it.
Nearly a hundred people from 18 countries were listed as participants in
the 192-page proceedings of the 4-day conference, which took place in Sanya,
China, in April 2002. More than three-quarters were scientists, with
policy-makers, representatives of non-government organisations, international
organisations, private companies and farmers making up the rest. Participants
from the host country China made up more than half of the total, and all were
scientists from prestigious rice research institutes, agriculture academies or
The conference was convened, not to assess whether SRI works for
that was the experience of almost everyone who presented papers at the
conference - but to assess across nations, "the opportunities and limitations"
of a practice that "can give yields about twice the present world average
without reliance on new varieties or agrochemicals."
The conference did bring together a substantial body of evidence from
around the world that SRI can increase yield in a variety of soils, climatic
conditions, with various local adaptations, and using both indigenous and
commercial high yielding rice varieties.
SRI has been "practice-led" thus far, but participants at the conference
felt it was time for scientists to catch up and research the knowledge-base, so
that a healthy dialectical relationship between practice and knowledge can be
achieved to help advance this important project of delivering food security and
health to more than half the worlds population.
Since then, more successes have been reported, leaving the scientific
establishment even further behind (see "Fantastic rice yields fact or
fallacy?" this series).
Super-yields in Madagascar
The province of Fianarantsoa, situated in the south-central highlands of
Madagascar, now lays claim to the highest yielding rice-fields in the world
since the introduction of SRI in the 1990s.
The highlands are subtropical, with annual rainfall averaging 1375mm.
The rainy season occurs during the hot months in the year, where the average
temperature rises above 20C. The Fianarantsao region is often affected by
cyclones during the rainy season.
Fianarantsoa attained rice yields of more than 8t/ha in the first year
of applying SRI methods, up from the 2t/ha national average. SRI in this region
is increasingly linked with the use of compost in rotational cropping with
potatoes, beans or other vegetables in the off-season. In the second and
succeeding years, the residual and cumulative effects of soil organic matter
from composting increased yields still further, to 16t/ha. By the sixth year,
yields as high as 20t/ha were measured on farmers fields in
Tsaramandroso, Talatamaty and Soatanana.
Bruno Andrianaivo, senior agronomist of FOFIFA (National Centre for
Applied Research on Rurual Development in Madagascar) emphasized that such high
yields cannot be achieved immediately, but requires the cumulative effects of 6
years under SRI.
However, simply on the conservative figure of 8t/ha yield from SRI
practice Andrianaivo estimated a net return to the farmer of 5 million Fmg
(about US$770), compared with around 250 000 Fmg (less than US$40) for
Acceptance in China
Professor Yuan Longping of China National Hybrid Rice Research and
Development Centre played a key role in creating high-yielding super-hybrids
throughout the late 1990s and early 2000s by conventional breeding methods. His
Centre had already broken all records in boosting rice-hybrid yields when he
first heard about SRI from a paper written by Norman Uphoff of Cornell
International Institute for Food, Agriculture and Development (see "Fantastic rice yields fact or
fallacy?" this series).
Yuan conducted the first trial of SRI in his Centres station in
Sanya from winter 2000 to spring 2001. Only three varieties yielded above
10t/ha, and SRI gave an average increase of around 10% over the conventional
practice. The following year, tests were conducted in the summer at the
Centres station in Changsha. Two varieties yielded 12t/ha, and one
12.9t/ha, a record for the Centre so far. This encouraged more Chinese
scientists to conduct SRI research. Of the 8 locations in which his Centre was
involved, 5 locations got good results, with yields over 12t/ha.
Since then, trials by a private sector company, the Meishan Seed Company
in Sichuan Province, using a modified SRI method, achieved yields of 15.67/ha
and 16t/ha in two different plots, both new records in Sichuan Province (yield
in the conventional field was 11.8t/ha).
Yuans preliminary evaluation of SRI is enthusiastic: "SRI is a
promising way to increase rice yield and to realize the yield potential of any
whether high-yielding variety (HYV) or local variety." He
confirmed that the method can promote more vigorous growth of rice plants,
especially tillers and roots, and noted in addition, less insect and disease
problems during the vegetative growth stage, and that there are definite
varietal differences in response to SRI practices: those with strong tillering
ability and good plant type are more favourable for SRI
cultivation. "SRI gives higher output with less input, but requires very
laborious manual work which makes it more suitable for small farms in
developing countries" he said. Moreover, SRI should be modified and adapted to
suit local conditions, and as experience teaches.
For China, he recommended a long list of modifications, including using
tray nurseries to raise the young seedlings instead of flooded seedbeds, so as
to reduce the trauma of transplanting; and controlling tiller-formation, for
although increased tillering gives many more rice-forming panicles, the
percentage of productive tillers falls off with the number of tillers, so there
is a optimum maximum number.
He definitely thinks there is scope for combining genetic improvement
with SRI methods. For example, breeding plants with a strong ability to form
tillers would be appropriate for improving the response to SRI.
Detailed analyses of the trials were presented in several multi-author
research papers. For example, the economic benefits of applying SRI methods
were estimated for the hybrid rice Liangyoupei 9, which came both from savings
and increased yield. The amount of hybrid seed needed in SRI methods was only 3
- 4.5kg, which represented a seed saving of 8.3 - 10.5kg and nursery saving of
90%, thereby reducing the cost by 215 Yuan/ha. As only compost was applied, the
saving on the 10-12t/ha fertilizer that would have been used was 1 200Yuan/ha.
The saving on water, some 3 000 tonnes, was about 150 Yuan/ha. The total saving
with SRI methods thus amounted to about 1 565 Yuan/ha. Add to that a 15%
increase in yield (1.5 tonnes/ha) and the farmer gets a total additional
profit of about 3 000 Yuan/ha (about US$ 360).
The Sichuan Academy of Agricultural Sciences has done SRI trials for
three years in succession. Its 2003, trials showed an average SRI yield of
13t/ha. Another series of trials in 7 regions of Zhejian Province using 8
varieties all resulted in increased yield under SRI; the average increase being
1.5t/ha over already high-yielding controls.
The China National Hybrid Rice Research and Development Centre
introduced hybrid varieties into Africa and recommended that they be used with
SRI methods. In 2003, a 9.2t/ha yield was obtained with hybrid GY032 in Guinea
under SRI methods, which was 4 times the national average yield.
SRI in Gambia
The Gambia, a small country (11 700km2) in West African, is a 50
km-wide ribbon of land extending eastward from the coast, bisected by the River
Gambia and surrounded on three sides by Senegal. Its annual rainfall is 900 to
1400mm; the rainy season between late May and early October. Rice is the staple
of the country and there are 5 very different production systems: upland,
lowland rainfed, irrigated (pump and tidal), freshwater swamps and seasonally
saline mangrove swamp.
Annual rice consumption averages 70 to 110kg per capita; domestic
production lags behind by 60%, and the balance is met by imports. The national
average yield of rice is only 2t/ha.
SRI was introduced to The Gambia in the rainy season of 2000 as part of
the Ph. D. thesis of Mustapha M. Ceesay in Crop and Soil Sciences at Cornell
University in the United States. Farmers were invited to visit the first SRI
trial site at the Sapu station of the National Agricultural Research Institute
(NARI) in The Gambia before they enrolled voluntarily in the research
During the first year of experimentation, three different plant
population densities were investigated with several varieties. Yields ranged
from 5.4 to 8.3t/ha. In 2001, plant population densities were investigated
alongside fertilizer treatments, and on-farm trials involving 10 farmer
households. The on-station SRI trials were conducted under pump irrigation, and
on-farm trials under tidal irrigation.
Plant population densities investigated were 20cm x 20cm, 30cm x 30 cm
and 40cm x 40 cm. Two rice varieties were used, and instead of compost, three
fertilizer treatment rates were assessed: NKP in the following proportions:
70-30-30 (national recommended), 140-30-30 and 280-30-30. All trials took place
in the lowland.
The on-station trials indicated that 30cm x 30cm spacing did not
decrease yield over the 20cm x 20cm, and was hence recommended to the farmers
for the on-farm trial. Fertilizer treatments indicated that under SRI, the
nationally recommended lowest rate was as effective as doubling the rate, while
tripling the rate gave higher yields, but it was not economically
The on-farm trials, conducted in a communal tidal irrigation scheme,
gave "exciting" results, "a tripling of yield" on average, 7.4t/ha
compared with 2.5t/ha obtained with farmers current practices. Some
farmers experienced more than five-fold increases, from 1.6 to 9.0t/ha in one
case, and 1.4 to 8.0t/ha in another.
But there are problems facing the farmers in land preparation. Farmers
in The Gambia still do not have a well-developed culture of water control.
Fields are simply kept flooded after transplanting until the rice plants
mature, and fertilizer application and weeding are done under submerged
conditions. These practices will conflict with the adoption of SRI, but the
yield increases may be a sufficient incentive for farmers to overcome these
SRI in other countries
Many countries reported remarkable increases in yield. Salinda
Dissanayake, Member of Parliament in Sri Lanka, personally tested SRI in his
own rice field of a little more than 2 acres for four seasons, using seeds of
various varieties. He got the highest yield of 17t/ha with BG358, a variety
developed by the Sri Lankan rice researchers. Even with local varieties such as
Rathhel and Pachdhaiperumal, usually much lower yielding at ~2t/ha, impressive
yields of 8t/ha and 13t/ha were obtained.
Dissanayake formed a small group to inform farmers of SRI; and farmers
who took up SRI from 18 districts have doubled their yields on average.
"These yields were obtained with less water, less seed, less chemical
fertilizer, and less cost of production per kilogram
among SRI users, we
find people of many different income and educational levels and different
social standing, including many poor farmers having only small plots of land,
farmers with moderate income, some agricultural scientists, and a few
administrators, businessmen and political leaders who practice it with their
own convictions." Dissanayake said.
H. M. Premaratna, a farmer from the Ecological Farming Centre,
Mellawalana, Sri Lanka, backed up the enthusiasm of his Member of Parliament,
and has personally provided training on SRI to more than 3 000 farmers by 2002.
"From my experience, I have observed that the rice plant becomes a healthier
plant once the basic SRI practices are adopted," he said.
Reports from 17 countries in 2002 showed that three-quarters of the
cases gave a significant yield advantage of at least 20 to 50% increase, and
although the super-yields reported from Madagascar have not been obtained
elsewhere, some farmers in Cambodia and Sri Lanka have come close. Overall, the
conventional systems yielded 3.9t/ha, very close to the world average for rice
production. The average for all the SRI yields reported was 6.8t/ha.
A report from the Philippines not only documented yield increases over
several successive growing seasons since 1999, but also a reduction of crop
pests such as rats and brown and green leafhoppers, carriers of the dreaded
rice tungro virus disease. This was attributed to the increased spacing of
plants, allowing more sunlight to penetrate even the base of the plant,
exposing the hoppers, which detest and avoid sunlight.
In Cambodia, SRI is spreading very rapidly. Only 28 farmers were willing
to try SRI in 2000, by 2003, this number had grown to almost 10 000 and in
2004, 50 000 farmers are expected to adopt it.
Perhaps the greatest testament that SRI works is the increasing number
of farmers that have adopted the practice.