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SRI ADVANTAGES
SRI has the
disadvantage of sounding "too good to be true."
This is the main reason why it was not taken seriously by agricultural
scientists for many years, though this is now changing. Also, it
is hard for farmers to believe, for example, that they can get twice
as much yield by using only 5 to 10 kg of seed per hectare instead
of the 50 to 100 kg per hectare they are used to using -- or that
they can achieve this by using only about half as much irrigation
water. Additional benefits of SRI are outlined in the 2005 Uphoff
article: Features of the System
of Rice Intensification apart from Increases in Yield (10p,
pdf).
SRI methods
increase the productivity of:
- water
-- since yields can double or more with only half as much water,
the productivity of water is greatly increased -- this is especially
important in countries or places where water is becoming scarcer;
- land
-- yields as indicated above can average about 8 t/ha once the
methods are used correctly, and can be twice that or more when
they are used with precision and skill;
- labor
-- SRI does require more labor - about 26% in one Madagascar evaluation,
11% in a Sri Lankan survey - but depending on the cost of labor,
the value of increased production increases the returns to labor
by at least 50% and often several hundred percent. Once the methods
have been mastered, the labor requirements for SRI decline. Also,
implements are being developed that save labor. In Cambodia, over
half the farmers using SRI now report that is is labor-saving
for them.
Environmental
Benefits: SRI is environmentally-friendly. Reduced
demand for water frees up water for other uses; soil that is not
kept saturated has greater biodiversity. Unflooded paddies do not
produce methane, one of the major "greenhouse gases" that
are contributing to global warming. There can be more nitrous oxide
from unflooded paddies, which offsets to some extent the gains from
reducing methane emissions, but when nitrogen fertilizer is not
used, this effect should be small. On balance, SRI should improve
environmental conditions.
Equity
Considerations: SRI also has the benefit of being particularly
accessible for farmers who have small landholdings and need to get
the highest yields possible from their available land. Since poorer
households have relatively more labor compared to land, SRI is one
of the few agricultural innovations that has a bias in favor of
equity. It is true that very poor households may find it difficult
to invest labor in SRI because they need to be earning daily incomes,
even if their returns to labor would be higher from SRI. However,
since returns to land, labor and water are all higher with SRI,
any household that grows rice and is labor-constrained will do better
by using SRI methods on just a part of its landholding, using its
other land for production of other crops when labor is available.
Active
Role for Farmers: SRI methods are most productive when used
with skill and care, so there will probably continue to be long-term
advantage for labor-intensive production with SRI. However, SRI
should be seen as a set of principles that are applied through various
techniques, rather than as a fixed technology to be adopted as a
"package." There is synergy
among practices that makes their use together more beneficial than
just using certain of the practices; but any of the practices should
give some improvement in yield. We anticipate that various kinds
of mechanization will over time make SRI suitable for larger scaler
production.
Farmers are
encouraged to experiment with the methods and to evaluate
the results for themselves, not just to "adopt" SRI. The
best spacing between plants, for example, needs to be determined
in relation to particular soil, climatic, hydrological and other
conditions. Exactly when and how to apply water depends on soil
characteristics and field position. So recommendations for spacing,
water management, age of seedling, etc. are not offered as universal.
Instead, principles are presented -- to be understood, tested
and adapted by users to suit their own conditions. It is hoped that
what farmers learn from using SRI may help them to become more innovative
producers in other respects.
Grain
Quality: When SRi paddy is milled, the outturn if
often proving to be higher, as there are fewer unfilled grains (less
chaff) and fewer broken grains (becasue they resist shattering).
In Andhra Pradesh, India, the rice millers association is promoting
SRI and paying a higher rice per bushel, as outturn has gone from
about 67% to about 75%. The sugar cooperative in Cuba that has pioneered
the new production methods in that country reports that its outturn
has gone up from 60% before to 68-71% now with SRI. This adds about
15% more productivity on top of the higher yields of paddy.
Faster
Maturing: Farmers are finding that SRI methods often,
though not always, reduce the time required for grain maturation.
In Camboida, on average, SRI crops are ripening about 7 days sooner
than regular crops of the same variety. In Andhra Pradesh, India,
ripening is 7-10 days sooner. (It has been alleged that SRI crops
take longer to mature, but this is not the experience in the field.)
In Nepal during monsoon season 2004, farmers got more than a doubling
of yield (3.37 to 7.85 t/ha) with a 15-day reduction in time to
maturity. Being able to harvest sooner reduces farmers' risks of
damage from pests or from typhoons, cyclones or other extreme weather
than can come the end of the season.
Health
Benefits: By reducing the application of agrochemicals
in rice production, the resulting grain has little or no chemical
residues. No systematic nutritional analyses have been done yet
on SRI grains, but the larger root systems could enhance their micronutrient
content, suggested by the higher grain wieght and greater resistance
to shattering. Many things are still not known about SRI in technical
terms. This page will be updated as more information becomes available.
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