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Improving Food Production for Health
in a Water-Constrained World: Opportunities from
Agroecological Knowledge and Experience (SRI)
Norman UphoffSRI International Network and Resources
Center (SRI-Rice), Cornell University
Water for Health Lecture Series,Nebraska Water Center, February 24, 2016
CHALLENGE: To support larger and healthier populations, we will need to
increase our global food production by >50% in the decades
aheadThis ambitious TARGET must be achieved with;•Diminishing arable LAND per capita -- so land-extensive strategies become less tenable •Supplies of WATER in large areas of the world are becoming both reduced and less reliable•We must conserve our NATURAL RESOURCES with growing concern for environmental quality•All this must be accomplished under conditions of CLIMATE CHANGE – which will affect the agriculture sector most adversely
THE GREEN REVOLUTION PARADIGM although reasonably successful in the 20th century is unlikely to serve us
as well in the 21st century• This technology is a ‘thirsty’ technology
which has relied mainly on genetic improvements and
inorganic/agrochemical inputs to raise yields
• In recent decades, its gains have been decelerating, and it has encountered
diminishing returns • It ignored two basic factors that
contribute to crop productivity and agricultural sustainability: root systems
and beneficial soil biota• Alternatives should at least be
considered.
Diminishing returns to fertilizer inputs
are very evident in Chinese experienceAt the start of China’s Green Revolution, farmers’ agronomic N-use efficiency was 15-20 kg rice/kg N•By 1981-83, this had fallen to 9.1 kg rice/kg N (Lin, 1991)• By 2001, it was 6.4 kg rice/kg N in
Zhejiang province (Wang et al., 2001)• By 2006, this ratio was 5-10 kg rice/kg
N (Peng et al., 2006) – and it is still declining
S.B. Peng et al., “Improving N fertilization in rice… “ Agronomy for Sustainable Development, 30 (2010),
649-656.
This has adverse environmental consequences as nitrate (NO3) levels in
China’s groundwater supplies have been rising rapidly, due to the overuse of N fertilizer – based on the belief that
if some is good, more is better?
Already >10 years ago, in many parts of China, the level of NO3 in groundwater was >300 ppm
-- in the US, EPA allowance is only 50 ppm
J.L. Hatfield, “Nitrogen over-use, under-use and efficiency.”
Paper presented to 4th International Crop Science Congress,
Brisbane, Australia, September, 2004
This kind of agricultural practice has unacceptable consequences and a
bleak future
The System of Rice Intensification (SRI) developed in Madagascar 30+
years ago is well-suited for the conditions of our 21st century
agricultureHigher yields per hectare -- with fewer inputs needed and with more resilience
to biotic and abiotic stresses•SRI is not a technology but methodology for crop management = new ideas and insights, thinking outside our current ‘boxes’•SRI does not depend on using new or improved varieties or on the purchase and use of inorganic fertilizers and agrochemicals•SRI reduces crop water requirements and is drought-tolerant•SRI crops are more resistant to pests & diseases – less chemicals•SRI-managed fields have less emission of greenhouse gases•More yield with lower production costs raises farmer income•All accomplished by making simple changes in age-old practices more productive PHENOTYPES from any GENOTYPE
Fr. Henri de Laulaniè on a field visit in Madagascar
SRI rice field in Madagascar with a traditional variety;
reported yield was 17 t/ha – could have been less
Good example of different
phenotypic expression of crop genetic potential
The stump of a rice
plant (modern variety) with 223
tillers and massive roots grown from a
single seed using SRI methods in Indonesia
--Panda’an, E. Java,
2009
Two plants of the same variety (VN 2084) and same age (52 DAS)
being grown in Cuba a better phenotype from the same genotype
Comparison trials at Al-Mishkhab Rice Research Station, Najaf, Iraq
0
50
100
150
200
250
300
IH H FH MR WR YR
Gra
in d
ry w
eigh
t(g/
hill)
Stage
SRI
IH H FH MR WR YR
CK Yellow leafand sheath
Panicle
Leaf
Sheath
Stem
47.9% 34.7%
Non-Flooding Rice Farming Technology in Irrigated Paddy FieldDr. Tao Longxing, China National Rice Research Institute, 2004
Other Benefits from Changes in Practices
1. Water saving – major concern in many places, also now have ‘rainfed’ version with similar results
2. Greater resistance to biotic and abiotic stresses – less damage from pests and diseases, drought, typhoons, flooding, cold spells [discuss tomorrow]
3. Shorter crop cycle – same varieties are harvested by 1-3 weeks sooner, save water, less crop risk
4. High milling output – by about 15%, due to fewer unfilled grains (less chaff) and fewer broken grains
5. Reductions in labor requirements – widely reported incentive for changing practices in India and China; also, mechanization is being introduced many places
6. Reductions in costs of production – greater farmer income and profitability, also health benefitsDrought-resistance in Sri Lanka: Rice fields 3 weeks after their irrigation was stopped because of drought --
conventionally-grown field is on left, and SRI field is on right-- same variety, same soil, same
climate
Storm resistancein Vietnam:
Adjacent fields after being hit by a tropical storm
in Dông Trù village,Hanoi province
On left: SRI fieldand rice plant; on
right, conventional field and plant
Same variety was used in both fields -- on right, we seeserious lodging;
on left, no lodging
Resistance to both biotic and abiotic stresses in East Java, Indonesia: both fields were hit by
brown planthopper (BPH) and tropical storm – field on left grown with standard practices; field on right
is organic SRI
Modern improved variety (Ciherang) – no yield
Traditional
aromatic variety
(Sintanur)
- 8 t/ha
SRI practices are now being used beyond rice with
the broader System of Crop Intensification (SCI) Farmer-led innovations with civil society
help improve:•Wheat (SWI) -- India, Nepal, Ethiopia, Mali•Sugarcane (SSI) -- India, Cuba, Tanzania•Finger millet (SFMI) -- India, Ethiopia•Mustard (rapeseed/canola) -- India•Sorghum – Ethiopia•Tef -- EthiopiaAlso: maize, soya bean, black gram, green gram, red gram, tomatoes, chilies, eggplant, sesame, green leafy vegetables, turmeric, cumin, coriander, etc. -- India, Ethiopia, Nigeria
SWI wheat crop in Bihar state of India, Chandrapura village, Khagarla district – wheat
fields are same age, same variety
Mature tef crop with full heads of grain under STI management in Ethiopia – in 2014/15, >2.2 million
farmers using ‘STI-lite’ DS methods
Spread/Adoption/Adaptation of SRI since 2000
More than 10 million farmers are benefiting from the use of SRI methods and ideas in >50 countries (end of 2015) on 3.5
to 4.0 million hectares
SRI-Rice (2014)
SRI is recommended practice for ‘save and
grow’ cultivation of rice (FAO, 2016)
Websites for information:World Bank:
http://info. worldbank.org/etools/ docs/library/245848/
IFAD: http://www.ifad.org/ english/sri/
IRRI: http://irri.org/news/hot-topics/system-of-rice-intensification-sri
Cornell University: http://sri.cals.cornell.edu
Evidence on water saving and productivity:
A meta-analysis of 29 published studies (2006-2013), with
results from 251 comparison trials across 8 countriesWater use: SRI mgmt 12.03 million
liters ha-1
Standard 15.33 million liters ha-1
SRI reduction in total water use = 22% SRI reduction in irrigation water use = 35%with 11% more yield: SRI 5.9 tons ha-1 vs. 5.1 tons ha-1
(usually SRI yield increase is much greater than this)Total WUE 0.6 vs. 0.39 grams/liter (52% more)Irrigation WUE 1.23 vs. 0.69 grams/liter (78%more)
P. Jagannath, H. Pullabhotla and N. Uphoff, “Evaluation of water use, water saving and water use efficiency in irrigated
rice production with SRI vs. traditional management,” Taiwan Water Conservancy (2013)
Year 2004
2005
2006
2007
2008 2009 201
0 Total
SRI area (ha) 1,133
7,267
57,400
117,267
204,467
252,467
301,067
941,068
SRI yield (kg/ha)
9,105
9,435
8,805
9,075
9,300 9,495 9,55
5 9,252Non-SRI yield (kg/ha)
7,740
7,650
7,005
7,395
7,575 7,710 7,74
0 7,545
SRI increment (t/ha)*
1,365
1,785
1,800#
1,680
1,725
1,785
1,815# 1,708
SRI % increase in yield*
17.6%
23.3%
25.7%
22.7%
22.8% 23.2% 23.5
% 22.7%Increased grain (tons） 1,54
712,9
71103,3
20197,0
08352,7
05450,6
53546,4
361,664,6
40Added net income due to SRI (million RMB)*
1.28 11.64
106.51
205.10
450.85
571.69
704.27
2,051($300
m)
* Comparison for SRI paddy yield and profitability is with Sichuan provincial average # In drought years, SRI yields were relatively higher than with conventional methods Source: Data are from the Sichuan Provincial Department of Agriculture.
CHINA: SRI in Sichuan -- evidence of drought resistance
More productive phenotypes give higher water-use efficiency within plants as measured by the ratio of photosynthesis : transpiration
For each 1 millimol of water lost by transpiration,
3.6 micromols of CO2 are fixed in SRI plants vs.
1.6 micromols of CO2 fixed in RMP plants
This becomes more important with climate change and as water becomes a scarcer
factor of production
“An assessment of physiological effects of the System of Rice Intensification (SRI) compared with recommended
rice cultivation practices in India,” A.K. Thakur, N. Uphoff and E. Antony
Experimental Agriculture, 46(1), 77-98 (2010)
Results of trials conducted by the China National Rice Research Institute over two
years, 2004-2005,using 2 super-hybrid varieties, with the aim of breaking the ‘yield plateau’ now
limiting hybridsStandard Rice Mgmt• 30-day seedlings• 20x20 cm spacing• Continuous flooding• Fertilization:– 100% chemical
New Rice Mgmt (~ 75% SRI)• 20-day seedlings• 30x30 cm spacing• Alt. wetting/drying (AWD)• Fertilization: – 50/50 chemical/organic
X.Q. Lin, D.F. Zhu, H.Z. Chen, S.H. Cheng and N. Uphoff (2009). “Effect of plant density and nitrogen fertilizer rates on
grain yield and nitrogen uptake of hybrid rice (Oryza sativa L.)” Journal of Agricultural Biotechnology and Sustainable
Development, 1(2): 44-53
Yields (kg/ha) with ‘new rice management’ vs. standard rice management at different plant densities/ha
0100020003000400050006000700080009000
10000
150,000 180,000 210,000
NRMSRM
Plant population per hectare
SRI practices yield more productive phenotypes -- Chinese farmers are WASTING seeds and water
and N fertilizer
Environmental Benefits with SRI:1. Reduced water requirements – higher crop water-use
efficiency -- puts less pressure on ecosystems in competition with agriculture for water supplies
2. Higher land productivity – reducing pressures for the expansion of arable area to feed growing populations
3. Less use of inorganic fertilizer – reactive N is “the third major threat to our planet after biodiversity loss and climate change” (John Lawton, former chief executive, UK National Environmental Research Council)
4. Less reliance on agrochemicals for crop protection - which enhances the quality of both soil and water
5. Buffering against the effects of climate change – drought, storms (resist lodging), cold temperatures
6. Net reduction in greenhouse gases (GHG) – CH4 can be reduced without an offsetting increase in N2O
WATER for FOOD for HEALTH• Farmers in developing countries, for whom and by whom
SRI and SCI have been evolved, should be able with their currently available resources to meet their own households’ and other’ food needs more satisfactorily than they can at present.
• The water requirements for this can be lowered by enhancing crop root growth and the abundance and diversity of the soil biota. These two fundamental factors for agricultural productivity were largely ignored -- and indeed were often impeded -- in the Green Revolution.
• An open question is the extent to which U.S. scientists and farmers can and will learn from this overseas experience, taking these ideas seriously and scaling-up agroecological modes of production -- SRI ideas + conservation agriculture?
