The document discusses the challenges of increasing global food production while using less water. It notes that over 1 billion people lack access to clean water, most freshwater is used for agriculture, and drought is a major cause of crop losses. Climate change is expected to increase temperatures and drought severity. Research is exploring ways to develop crop varieties with greater drought tolerance and water use efficiency to help address rising water scarcity and demand for food. Traits like maintaining growth under drought and accessing more soil water are desirable for drought-tolerant varieties.

1. Producing more food with less water:
a global challenge
Eric Ober
Broom’s Barn Research Station

2. FAO Briefing paper: Hunger on the rise, Sep, 2008

3. FAO Food Outlook, November, 2008

5. “I wish to reaffirm that we know what needs to be done to eradicate the
hunger of 923 million people in the world. We also know what needs to be
done to double world food production and feed a population that is expected
to rise to 9 billion people by 2050. What we need ... is political will and
delivery on financial commitments, if we are to be able to make the essential
investments that are needed to promote sustainable agricultural
development and food security in the poorest countries of the world.”
--FAO Director-General Jacques Diouf, World Food Day, October, 2008

6. Challenges to global food production
• Climate change
• Competition with biofuels
• Soil fertility
• Input and commodity prices
• Availability of credit

7. CLIMATE CHANGE AND
FOOD SECURITY: A
FRAMEWORK DOCUMENT,
FAO, 2007

9. How does climate change affect crops?
• More CO2 and warmer temperatures will
increase yields
• Greater evaporative demand and less rainfall
• Droughts will become more frequent and
severe
• Increased probability and severity of heat
waves

10. By 2050 the maximum summertime temperatures
in East Anglia will have increased by 3 °C.
30
Monthly maximum temperature (°C)
25
20
15
10
Real (1976-2005)
Base
5 HI2020
HI2050
HI2080
0
1 2 3 4 5 6 7 8 9 10 11 12
Month

11. …and the amount of summertime rainfall
will have decreased.

12. How will future weather affect crop
production in the UK?

13. 20
Sugar yield (t/ha)
15
10
Silt loam
Clay loam
5
Sandy loam
Sandy
0
Baseline 2020HI 2050HI 2080HI
Scenarios

14. Climate change effects on sugar beet
Positive aspects
• Warmer Springs
• earlier sowing, faster canopy development,
more light capture
• Increased CO2
• photosynthetic productivity
• Fewer winter freezing spells (-5°C)
• Less in-field frost damage

15. Climate change effects on sugar beet
Negative aspects
• Less summer rainfall, drought stress
• Higher summer temperatures
• heat stress, increased Cercospora
• Warmer winters, increased pest survival
• More variable weather, extreme events

16. 25-7-08

17. Insufficient water is the most important
cause of yield loss in the UK beet crop
• Average potential evapotranspiration
(June-Aug) for East Anglia = 350 mm H2O
• Average (June-Aug) rainfall = 150 mm H2O
• Average annual yield loss = 10%
• Jaggard et al. (1998) J Ag Sci 130: 337-43

18. Cost of drought to UK winter
wheat production
• 30% of wheat acreage grown on drought-
prone land
• Annual losses (national average) of:
• 1-2 t ha-1
• >£ 40 million
• Foulkes et al. (2004) Proceedings of the 4th International Crop Science Congress, Brisbane, Australia

19. • Increased demand
for food
• Water availability
limits yield
Increase rainwater catchment
Improve soil fertility and water-
holding capacity
Increase irrigation and irrigation
efficiency
Improve varieties
drought tolerance
water use efficiency

20. Research Objectives
• Identify genotypes with greater drought tolerance and
water use efficiency (WUE) than current commercial
varieties
• Identify traits that are associated with drought tolerance
and WUE
• Develop screening tools that can be used by breeders to
select superior varieties
• Use variety trial data to discover which current varieties
show better drought tolerance or susceptibility

22. Some breeders’ experimental hybrids show better drought
tolerance than current commercial varieties
TS05
7.3 t sugar ha-1
3GR1810
5.6 t sugar ha-1

23. Characteristics of a successful drought tolerant
variety
• Maintains productive foliage and delays
wilting and senescence
• Accesses more soil water
• Produces thinner leaves and cooler canopy
• Recovers growth faster following recovery
from stress

24. 120 winter wheat genotypes grown under
managed drought and irrigated conditions, 2008

25. Wheat genotypes show significant differences
in drought tolerance
25
LSD0.05 = 0.3***
Number of genotypes
20
15
10
5
0
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
Drought tolerance index

26. Drought tolerance does not necessarily demand
a large penalty in yield potential
1.6
1.4
Drought tolerance index 1.2 Select
1.0
0.8
Reject
0.6
LSD
0.4
r2 = 0.07
0.2
2 4 6 8 10 12 14
Well watered grain yield (t ha-1)

27. CPBT W97 Einstein
Gatsby Except

28. How to improve drought tolerance
Finished Evaluate performance
variety across multi-location
variety trials
yield potential
Stability +
Screen for
Initial secondary
crosses traits
Varieties suited for
drought-prone land

29. Action
• Mitigation – adopting practices that reduce or
remove greenhouse gas emissions
• Analyse and improve your business’ ‘carbon footprint’
• Reduce nitrous oxide (N2O) emissions from soil N
• Look at what we grow and how we grow it
• Adaptation – making the changes necessary to
be profitable in a changing environment
• Invest in R&D
• Drought tolerance
• Disease resistance

30. Action-water resources
• Conduct ‘water use audit’
• Improve irrigation efficiency
• Decrease water waste
• Consider rainwater catchment, water
recycling
• Join local WAG, participate in CAMS

31. Action-water resources
• Irrigation efficiency
• MOT equipment
• Check raingun pressure
• Use water meters
• Minimise wind effects
• Check uniformity
• Use scheduling

32. http://www.ukia.org
http://www.environment-agency.gov.uk/

33. “Weiji” = crisis
“Wei” = danger
“ji” = opportunity

34. Sponsors and collaborators: wheat

35. Sponsors and collaborators: sugar beet

39. Sugar yields have been steadily increasing
16
14
12
Sugar yield (t ha )
-1
10
8
6
4
Official variety trial yield (204 kg/ha/yr)
2
Farmer delivered yield (111 kg/ha/yr)
0
1975 1980 1985 1990 1995 2000 2005
Crop year

40. Rainfed yields are more variable, and ~2 t less
than irrigated yields.
18
16
Sugar yield (t ha-1) 14
12
10
8
6
4
Irrigated
2 Rain-fed
0
1975 1980 1985 1990 1995 2000 2005
Crop year

41. Reasons for yield increases
• Improved varieties
• Better farming practices
• What about the weather?

43. Genotypic diversity for waxiness
Leaf wax score: 0 to 5

44. Climatic effects can explain much of recent
yield increases
kg sugar/ha per
%
year
Total increase
204 100
(variety trials)
Climate 114 56
Earlier sowing 25 12
Better varieties and
65 32
agronomy

45. Since 1976 ……Conclusions
• Improved weather accounts for >50% of
the yield increase
• Earlier sowing was made often possible
because varieties/seeds have improved
• Better varieties/seeds account for >30% of
yield increase – mostly the variety effect

46. Wheat
Change: 2008/09
2006/07 2007/08 2008/09 over
estim. f’cast 2007/08
million tonnes %
WORLD BALANCE
Production 596.6 610.5 677.0 10.9
Trade 113.3 111.2 119.0 7.0
Total utilization 619.2 615.8 643.3 4.5
Food 442.9 446.4 451.1 1.0
Feed 111.6 101.0 120.3 19.1
Other uses 64.6 68.4 72.0 5.3
Ending stocks 159.9 155.1 186.6 20.3
SUPPLY AND DEMAND INDICATORS
Per caput food consumption:
World (kg/year) 67.9 67.6 67.5 -0.2
LIFDC (kg/year) 58.4 58.1 58.0 -0.2
World stock-to-use ratio % 26.0 24.1 29.5
Major exporters’ stock-to-disappearance
14.9 10.9 16.7
ratio %
Change:
2006 2007 2008
Jan-Oct 2008
over
Jan-Oct 2007
Wheat Price Index %
(1998-2000=100) 145 216 302* 52
FAO Food Outlook, November, 2008

47. • >1 billion people lack access to
safe drinking water
• 70 per cent of all available
freshwater is used for agriculture
• 0.5 t of water required to
• United Nations produce 1 kg grain or sugar
• International Decade for
Action
• Deficit in natural aquifers
grows by 160 x 107 m3/yr
• Drought causes more
crop losses than any other
single biotic/abiotic factor
Boyer JS (1982) Science 218: 443-8
data: UNESCO

48. Evaluating surrogate measures of water use efficiency
2005 Diallel Experiment-Glasshouse
24.0 Seasonal summed
water use
Leaf Delta (parts per mil)
23.5
23.0
22.5
Abouzar Rajabi and
Prof. Howard Griffiths,
U. Cambridge 22.0
21.5
2
r = 0.42***
21.0
6 7 8 9 10 11 12
Water use efficiency (g kg-1)
13C/12C discrimination ratio (∆) is negatively correlated with
WUE.