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Title: Insights into Plant-Microbial Symbiosis and Implications for Sustainable Agriculture –Giving Attention to ‘Inner Space’ Date: 26 January 2013 Presented by Norman Uphoff at the National Institute for Agricultural and Forestry Research (IDIAP), Santo Domingo, Domincan Republic
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Insights into Plant-Microbial Symbiosis and
Implications for Sustainable Agriculture –
Giving Attention to ‘Inner Space’
Norman Uphoff, SRI-Rice, Cornell University
National Institute for Agricultural and Forestry Research (IDIAP),
Santo Domingo, January 26, 2013
A challenge for our 21st century agriculture
is to produce MORE with LESSNecessary to achieve sustainable development• This may sound impossible or
improbable• However, it may be achieved by working
more successfully within the realm of BIOLOGY, which operates differently from the realms of chemistry and engineering – can be ‘win-win’
Transformation of inputs into outputs is a generic process;
however, BIOLOGY operates within open systems with options for
mobilizing energy and nutrients that are otherwise unutilized or
underutilized
In the 21st century agriculture,we cannot just do ‘more of the
same’• Arable land area per capita is reducing as
• Populations continue to grow, while
• Land area is being lost to urban spread, and
• Land degradation is increasing year by year
• Water supply for agriculture is declining
• Competing demands for domestic use and industry
• Climate change is reducing amount and reliability
• Pests and diseases are likely to increaseIn the US, crop losses to insects rose from 7% to
13%, while the use of insecticides was increased by
14x
• Future energy prices will be higher in this centure than in the 20th century, affecting:
• Production costs: fuel, fertilizer, agrochemicals
• Transport cost: long-distance trade more costly
• Climate patterns will become less favorable
• Impact will be greatest in poorest countries
• Accessibility of technology remains big issue
• The Green Revolution by-passed most of the world’s poor ; must enable them to meet needs
• Scale-neutral technologies are most desirable
• Agric. productivity gains have slowed down
GREEN REVOLUTION TECHNOLOGY
was based on two main factors:A. Improvements in GENETIC
POTENTIALS, i.e., in crop and animal genotypes (varieties)
B. Increasing application of EXTERNAL INPUTS -- inorganic fertilizers, biocides, etc.
These elements were successful in the past, but:
• Economic costs of production are increasing,
• Environmental costs are increasing, and now
• Diminishing returns are evident, e.g., in China, the ratio of additional rice production from 1 kg of N has fallen from 20:1 to 5:1, and still declining
Where do we go from here?More of the same,
but better?
Green Revolution was shaped more by chemistry, engineering
and genetics than by biology (physiology and microbiology)
and by ecologyIt ignored the contributions
made by plant roots and by the soil biota
Our challenge for sustainable agriculture is to produce MORE OUTPUT with REDUCED
INPUTSlearning how to get more productive
PHENOTYPES from available GENOTYPES – can be done by makingbeneficial changes in crops’ growing
environmentsThe System of Rice Intensification (SRI) developed in Madagascar has shown how farmers can get more productive rice plants from existing varieties (local, HYVs, hybrids) at same time giving crops more resistance to effects of CLIMATE-CHANGE:
• More DROUGHT resistance• Resistance to STORM DAMAGE (less
lodging)• More resistance to PEST & DISEASE
HAZARDS• Even some tolerance of temperature
extremes Its methods are being adapted to many OTHER CROPS
The Basic Ideas for SRI/SCI:• Establish healthy plants early (young) and
carefully, making efforts to maintain their root growth potential.
• Reduce plant density, giving each plant more room to grow, both above-ground and below-ground, to capture more sunlight and obtain more soil nutrients.
• Keep the soil well-aerated and enriched with organic nutrients, as much as possible, so that it can support better growth of roots and more aerobic soil biota.– Apply water in ways that can best support the
growth of plant roots and of beneficial soil microbes, avoiding continuous inundation and anaerobic soil conditions.
– Control weeds in soil-aerating way (mechanical weeder).
When used together, these practices enable farmers to: (a) increase the size and functioning of ROOT SYSTEMS, and (b) enhance the populations of beneficial SOIL BIOTA.
Farmer witha rice plantgrown from
a single seed with
SRI methods in Morang district of
NEPAL
Farmer with two plants of same variety (VN 2084) and same age
(52 DAS) in CUBA
Comparison trials at Al-Mishkhab Rice Research Station, Najaf, in IRAQ
SRI
0
50
100
150
200
250
300
IH H FH MR WR YRStage
Org
an d
ry w
eigh
t(g/
hill)
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
SRI methods have set a new world record
Paddy production: Bihar panchayat breaks China’s recordNew Delhi, Mar 20: A gram panchayat in Nalanda district of Bihar has surpassed the Chinese record of paddy production, the Union Agriculture Minister Mr Sharad Pawar informed Parliament today. “As per the reports received from the state government, the yield of wet paddy has been recorded at 22.4 tonnes per hectare and that of dry paddy at 20.16 tonnes a hectare ...,” Mr Pawar said in a written reply to Lok Sabha. The record yield was achieved under demonstration on System of Rice Intensification (SRI) which was organised at farmer’s field during kharif 2011, he added. “It has surpassed the yield of 19 tonnes per hectare which was recorded earlier in China.”
Before 1999: Madagascar1999-2000: China, Indonesia2001-02: Bangladesh, Cuba, Laos, Cambodia, Gambia, India, Nepal, Myanmar, Philippines, Sierra Leone, Sri Lanka, Thailand2003: Benin, Guinea, Mozambique, Peru 2004-05: Senegal, Pakistan, Vietnam2006: Burkina Faso, Bhutan, Iran, Iraq, Zambia
2007: Afghanistan, Brazil, Mali 2008: Rwanda, Costa Rica, Egypt, Ecuador, Ghana, Japan 2009: Malaysia, Timor Leste2010: Kenya, DPRK, Panama, Haiti2011: Colombia, Korea, Taiwan, Tanzania 2012: Burundi, Dominican Republic, Niger, Nigeria, Togo (total of 51)
2012: >50 countries of Asia, Africa, and Latin America where SRI’s phenotypic benefits have
been seen
Agroecological methods can give significant increases in yield,
by multiples rather than increments,for resource-limited households
with reduced inputs (seeds, water, fertilizer)
* ‘Intensification’ is of farmer’s knowledge,
skill and management -- rather than of purchased inputs – but also, with
mechanization it is possible to save labor
* Changes are made in the management of
plants, soil, water and nutrients to affect
the populations and activity of soil biota
INDONESIACaritas introduced
SRI methods in Aceh in 2005 after
tsunami devastation – local rice yields were
raised from 2 t/ha to 8.5 t/ha
“Using less rice seed, less water and organic compost,
farmers in Aceh have quadrupled their crop production.”
‘Rice Aplenty in Aceh,’ Caritas News (2009) Similar quadrupling of yield by poor, food-insecure,
resource-limited households has been documented also in Madagascar, Cambodia, and Madhya Pradesh (India)
INDIA: Report in
The HINDUNov. 28, 2011
on SRI results inMadhya Pradesh
SRI methods were introduced in Damoh district of Madhya Pradesh state by Gramin Vikas Samiti, with support from the People’s Science Institute
(PSI)More than 1,200 farmers in 32 villages increased their
average paddy yields from 1.7-2.0 t/ha to 7.5-8.0 t/ha
with minimum of 4.4 t/ha and maximum of 11.5 t/ha -- using traditional varieties and with organic
management
SRI panicle with traditional variety (top); HYV panicle with usual mgmt
(bottom)
Hang Hein’s field was transplanted in one day by his 3 sons below;
traditional transplanting methods are shown on right; with SRI crop
management, Hang Hein’s yield went from 1.25 t/ha to 5 t/ha
CAMBODIA: SRI introduced in Kampong Chhnang province
in 2006-2007 by LDS Charities, with 146 farmers whose
rainfed yields had previously averaged just 1.06 t/ha --
their yields with SRI practices averaged 4.02 t/ha
These changes in crop management
are effective in very different andquite contrasting agroecosystems:
* AFGHANISTAN: Baghlan province
1600 masl, temperate climate;short growing season
* MALI: Timbuktu province on edge of Sahara Desert;hot, dry tropical climate
AFGHANISTAN: SRI field in Baghlan Province, supported by Aga Khan Foundation Natural
Resource Management program
AKF technician making a field visit in Baghlan province
SRI field at 30 days
SRI plant with
133 tillers @
72 days after
transplanting
11.56 t/ha
* Some areas could not continue or be measured because of Taliban
SRI yields were achieved with reductions in water
Year
SRI Users
SRI Yield
Conv.
Yield
2008 6 10.1 5.4
2009 42 9.3 5.6
2nd yr
[7] [13.3] [5.6]
1st yr
[35] [8.7] [5.5]
2010 104 8.8 5.6
2011 114* 10.01 5.04
MALI -- SRI nursery in Timbuktu region – 8-day seedlings ready for transplanting
SRI transplanting on edge of Sahara
Desert
Malian farmer in the Timbuktu region
showing the difference between
regular and SRI rice plants
with 32% less water
Gao region: 7.84 t/haMopti region: 7.85
t/ha
Year
SRI Users
SRI Yield
Conv. Yield
2007-08 1 8.98 --2008-09 60 9.01 5.492009-10 130 7.71 4.48
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 – reducingpressures for the expansion of arable area to feed our 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 the effects of climate change – drought, storms (resist lodging), cold temperatures, etc.
6. Possible reduction in greenhouse gases (GHG) – CH4 is reduced apparently without producing offsetting N2O
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 benefits
Drought-resistance: Rice fields in Sri Lanka, same variety and same soil 3 weeks after irrigation had stopped because of drought – conventional rice
field (left) and SRI (right)
INDIA: Results from Bihar State, 2007-2012
SYSTEM OF RICE INTENSIFICATION -- state average yield: 2.3 t/ha
2007 2008 2009 2010 2012
Climatic conditions
Normal rainfall
2x flooding
Drought + rain in Sept.
Complete
drought
Good rainfall
No. of smallholders 128 5,146 8,367 19,911 NR Area under SRI (ha) 30 544 786 1,412 335,000 SRI yield (t/ha) 10.0 7.75 6.5 3.22* 8.08 Conv. yield (t/ha) 2.7 2.36 2.02 1.66* NR
,
SYSTEM OF WHEAT INTENSIFICATION -- state average yield: 2.4 t/ha
2007-08 2008-09 2009-10 2011-12 No. of smallholders 415 25,235 48,521 NR Area under SWI (ha) 16 1,200 2,536 183,085 SWI yield (t/ha) 3.6 4.5 NA 5.1 Conv. yield (t/ha) 1.6 1.6 NA NR
* Results from measurements of yield on 74 farmers’ SRI and conventional fields
Year2004
2005
2006
2007
2008
20092010
Total
SRI area (ha)1,13
37,26
757,40
0117,2
67204,4
67252,4
67301,0
67941,0
68
SRI yield (kg/ha)9,10
59,43
58,805 9,075 9,300 9,495 9,555 9,252
Non-SRI yield (kg/ha)
7,740
7,650
7,005 7,395 7,575 7,710 7,740 7,545
SRI increment
(t/ha)*1,36
51,78
51,80
0#
1,680
1,725
1,785
1,815#
1,708
SRI % yield
increase *17.6
%23.3
%25.7% 22.7% 22.8% 23.2% 23.5% 22.7%
Grain increase
(tons)1,54
712,9
71103,3
20197,0
08352,7
05450,6
53546,4
361.66 mill
Addl. net income fromSRI use (million
RMB)*1.28
11.64
106.5
205.1
450.8
571.7
704.3
2,051
(>$300 mill)
* Comparison with Sichuan provincial average for paddy yield and SRI returns # Drought years: SRI yields were relatively better than with conventional methods Source: Data are from the Sichuan Provincial Department of Agriculture.
CHINA: SRI extension/impact in Sichuan Province, 2004-10
Storm resistance: Dông Trù village,Ha Noi province, Vietnam, after
fields were hit bya tropical storm
Right: conventional
field and plant;Left: SRI field
and plant
Same variety usedin both fields:
serious lodging seen on right --
no lodging on left
Irrigation method
Seedling age
Spacing(cm2)
Plant lodging (in percent)
Partial Complete Total
Inter-mittent
irrigation (AWDI)
1430x30 6.67 0 6.67
30x18 40.00 6.67 46.67
2130x30 26.67 20 46.67
30x18 13.33 13.33 26.67
Ordinary irrigation (continuo
us flooding)
1430x30 16.67 33.33 50.00
30x18 26.67 53.33 80.00
2130x30 20 76.67 96.67
30x18 13.33 80 93.33
Lodging of rice as affected by irrigation practices when combined with different ages of
seedlings and different spacings in trials done in Chiba, Japan
(Chapagain and Yamaji, Paddy and Water Environment, 2009)
Disease and pest resistance: Evaluation byVietnam National IPM Program, 2005-06 –
averages of data from on-farm trials in 8 provinces
Spring season Summer season
SRIplots
Farmer
plots
Differ-ence
SRIplots
Farmerplots
Differ-ence
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%
* Insects/m2
Resistance to both biotic and abiotic stresses: fields in East Java, Indonesia hit by both brown
planthopper (BPH) and by storm damage (typhoon): rice field on left was managed with
standard practices; organic SRI is seen on right
Modern improved variety
(Ciherang) – no yield
Traditional
aromatic variety
(Sintanur)
- 8 t/ha
Resistance to cold temperature: Yield and meteorological data from ANGRAU, A.P.,
India
Period Mean max. temp. 0C
Mean min.
temp. 0C
No. of sunshine hrs
1 – 15 Nov 27.7 19.2 4.9
16–30 Nov 29.6 17.9 7.5
1 – 15 Dec 29.1 14.6 8.6
16–31 Dec 28.1 12.2# 8.6# Sudden drop in minimum temp. for 5 days (16–21 Dec
= 9.2-9.9o C )
Season Normal (t/ha) SRI (t/ha)
Kharif 2006 0.21* 4.16
Rabi 2005-06 2.25 3.47
* Low yield was due to cold injury (see below)
Comparison of methane gas emission
CT SRI
kg C
H4
/ ha
0
200
400
600
800
1000
840.1
237.6
72 %
Treatment
Emission (kg/ha)CO2 ton/ha equivalentCH4 N2O
CT 840.1 0 17.6
SRI 237.6 0.074 5.0
SRI practices are being used beyond RICE:
Farmer-led innovations with civil society help in:
• Wheat (SWI) -- India, Nepal, Ethiopia, Mali
• Sugarcane (SSI) -- India, Cuba
• Finger millet (SFMI) -- India, Ethiopia
• Mustard/rapeseed/canola (SMI) -- India
• Teff (STI) -- Ethiopia
• Sorghum (SSI2) – Ethiopia
• Turmeric (STI2) -- India
System of Crop Intensification (SCI): maize, black gram, green gram, red gram, tomatoes, chillies, eggplant, sesame, etc. -- India, Ethiopia
Wheat: SWI (left) vs. conventional plants in Bihar, India
Phenotypical differences in wheat panicles
with SWI practice seen
in Nepal
Tef: Application of SRI concepts &
practicesto production of tef
(STI) in Ethiopia
Left: transplanted tefRight: broadcasted
tef
3-5 t/ha vs. 1 t/ha
STI tef crop in Tigray province of Ethiopia
ICRISAT-WWFSugarcane Initiative:
• 20-100% more
cane yield, with • 30% reduction in
water, and • 25% reduction in
chemical inputs
“The inspiration for putting
this package together is from the successful approach of SRI –
System of Rice Intensification.”
Sugarcane: SSI cane plants seen in
India – SSI is now getting
started in Cuba,known as SiCAS
CUBA: SicAS sugarcane
@ 10.5 monthsEventual yield was
estimated @ 150 t/ha
Crops Yield increases Finger millet 3-4x Legumes 50-200% Maize 75% Mustard 3-4x Sugarcane 20-100% Tef 3-5x Turmeric 25% Vegetables 100-270% Wheat 10-140%
SCI crops are mostly rainfed, but 30% water-saving with wheat and sugarcane,
66% with turmeric
Summary of results reported from farmers' fields for
System of Crop Intensification (SCI)applying SRI concepts and methods to other crops
These results do NOT argue against making further genetic
improvements or against the use of external inputs
They suggest, however, that progress can be made right now at low cost -- with saving of water & buffering
against climate change -- by changing crop management practices, especially by attending to the
purposeful nurturing of roots and soil biota
WHAT IS GOING ON?
SRI/SCI shows us the importance of
abundance, diversity and activity of beneficial SOIL ORGANISMS promoted by soil organic matter
and by exudates from large, functioning ROOT SYSTEMS
that support plant growth and health
We are just starting to understand better the
contributions of symbiotic endophytes to mobilizing the services of plant microbiomes
that aid crops
Soil-aerating hand weeder in Sri Lanka costing <$20
Effects of Active Soil Aeration
412 farmers in Morang district of Nepal when using SRI in monsoon
season, 2005SRI yield = 6.3 t/ha vs. control yield =
3.1 t/haData show how WEEDINGS can raise
yield
No. of No. of Average Range
weedings farmers yield of yields
1 32 5.16 (3.6 - 7.6)
2 366 5.87 (3.5 - 11.0)
3 14 7.87 (5.85 - 10.4)
Mechanical
Weedings
Farmers (N)
Area (ha)
Harvest(kg)
Yield (t/ha)
0 2 0.11 657 5.9731 8 0.62 3,741 7.7232 27 3.54 26,102 7.3733 24 5.21 47,516 9.1204 15 5.92 69,693 11.772
Impact of weedings on yield with SRI methodsin Ambatovaky, Madagascar, 1997-98
ENDOPHYTIC AZOSPIRILLUM, TILLERING, AND RICE YIELDS WITH CULTIVATION PRACTICES AND NUTRIENT AMENDMENTS Replicated trials at Anjomakely, Madagascar, 2001 (Andriankaja, 2002)
CLAY SOIL Azospirillum
in roots (103 CFU/mg)
Tillers/ plant
Yield (t/ha)
Conventional methods, with no soil amendments
65 17 1.8
SRI cultivation, with no soil amendments
1,100 45 6.1
SRI cultivation, with NPK fertilizer
450 68 9.0
SRI cultivation, with compost
1,400 78 10.5
LOAM SOIL SRI cultivation with no soil amendments
75 32 2.1
SRI cultivation, with compost
2,000 47 6.6
Microbial populations in rice rhizosphere
Tamil Nadu Agricultural University research
Microorganisms
Conventional methods
SRI methods
Total bacteria 88 x 106 105 x 106
Azospirillum 8 x 105 31 x 105
Azotobacter 39 x 103 66 x 103
Phosphobacteria
33 x 103 59 x 103
T. M. Thiyagarajan, WRRC presentation, Tsukuba, Japan, 2004
Total bacteria Total diazotrophs
Microbial populations in rhizosphere soil in rice crop under different management
at active tillering, panicle initiation, and flowering (conv. = red; SRI = yellow). Units are √ transformed values of population/gram of dry
soil (data from IPB)
Phosphobacteria \ Azotobacter0
10
20
30
40
Dehydrogenase activity (μg TPF) Urease activity (μg NH4-N))
Microbial activities in rhizosphere soil in rice crop under different management
(conv. = red; SRI = yellow) at active tillering, panicle initiation, and flowering stages Units are √ transformed values of population/gram
of dry soil per 24 h
Acid phosphate activity (μg p-Nitrophenol)\
Nitrogenase activity (nano mol C2H4)
Effects of symbiotic microorganisms
in rice plants go beyond the root zone (the rhizosphere)
They also extend upward into the shoot & leaves (phyllosphere) and
even seeds
Contributions made by symbiotic endophytes are just starting to be well documented and widely
known
“Ascending Migration of Endophytic Rhizobia, from Roots and Leaves, inside Rice Plants and
Assessment of Benefits to Rice Growth Physiology”
Feng Chi et al., Applied and Envir. Microbiology 71 (2005), 7271-7278
Rhizo-bium strain
Total plant root
vol/pot (cm3) ± SE
Shoot dry
wt/pot (g) ± SE
Net photosyn-thesis rate (µmol of
CO2 m-2 s-1) ± SE
Water utilization efficiency
± SE
Grain yield/po
t(g) ± SE
Ac-ORS 571
210 ± 36A
63 ± 2A
16.42 ± 1.39A
3.63± 0.17BC
86 ± 5A
Sm-1021
180 ± 26A
67 ± 5A
14.99 ± 1.64B
4.02 ± 0.19AB
86± 4A
Sm-1002
168 ± 8AAB
52 ± 4BC
13.70 ± 0.73B
4.15 ± 0.32A
61± 4B
R1-2370
175 ± 23A
61 ± 8AB
13.85 ± 0.38B
3.36 ± 0.41C
64± 9B
Mh-93 193 ± 16A
67 ± 4A
13.86 ± 0.76B
3.18 ± 0.25CD
77 ± 5A
Control 130 ± 10B
47 ± 6C
10.23 ± 1.03C
2.77 ± 0.69D
51 ± 4C
“Proteomic analysis of rice seedlings infected by Sinorhizobium meliloti 1021”
Feng Chi et al., Proteomics 10 (2010), 1861-1874
Data are based on the average linear root and shoot growth of three symbiotic (dashed line) and three nonsymbiotic (solid line) plants.
Arrows indicate the times when root hair development started.
Ratio of root and shoot growth in symbiotic and nonsymbiotic rice plants --
seeds were inoculated with the fungus Fusarium culmorum vs. controls
R. J. Rodriguez et al., ‘Symbiotic regulation of plant growth,
development and reproduction” Communicative and Integrative Biology, 2:3 (2009).
Growth of nonsymbiotic (on left) and symbiotic (on right) rice seedlings.
On the growth of endophyte (F. culmorum) and plant inoculation procedures, see Rodriguez et al., Communicative and
Integrative Biology, 2:3 (2009).
More productive phenotypes also can give higher water-use efficiency as
reflected in the ratio of photosynthesis to transpiration
For each 1 millimol of water lost by transpiration:
3.6 millimols of CO2 are fixed in SRI plants,
1.6 millimols of CO2 are fixed in RMP plants
This is ever more important with climate change
“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)
Economics, environmental vulnerabilities, and climate change effects will all require a different kind
of agriculture in 21st century.We need to RE-BIOLOGIZE
AGRICULTURE
Fortunately, opportunities for a paradigm shift are available -- but they will require significant changes in our crop and soil
sciences, with work in disciplines of microbiology, physiology, soil ecology, and epigenetics becoming more central
Closing thought: Darwin’s ‘tree of life’ was
good taxonomy, but not very good biology --
need to appreciate inhabitants of ‘inner space’
For more information on SRI/SCI:
SRI International Network andResources Center (SRI-Rice)
Website: http://sri.ciifad.cornell.edu
based at Cornell International Institute for Food, Agriculture and
Develoment (CIIFAD), Cornell University, or contact
Norman Uphoff: [email protected]