Presentation by Dr. David Hodson (CIMMYT, Ethiopia) at Wheat for Food Security in Africa conference, Oct 9, 2012, Addis Ababa, Ethiopia.

1. Rust Bowl or Breadbasket?
Keeping track of wheat rust
pathogens in Africa
Dave Hodson1 and Kumarse Nazari2
1CIMMYT-Ethiopia Email: d.hodson@cgiar.org
2ICARDA Email: k.nazari@cgiar.org

2. Africa: Critical for Global Rust Control
 “The kitchen where the
pathogen is cooked” P.
Njau, KARI
“rust is a shifty, changing, constantly evolving
 Key Driving Factors:
enemy. We can never lower our guard .” EC
 Continuous wheat : Green
bridge
Stakman, 1937.
 Genetic uniformity of
commercial cultivars
 High WE DID LOWER OUR GUARD! Rust
BUT elevation/high UV research
was forgotten in East Africa 1980’s - 2000
radiation (increased
mutations). Wide range of
environments
 Alternate hosts? E.g.,
Berberis holstii

3. Out of Africa?: Dangerous Exports
 East Africa is a 1992/3 1993/4
center for new 1991
1994/5
emerging rust
races (Yr9, Ug99 Yr9 1995/6
etc). 1991
 Mid 80’s to mid
1986
90’s - Yr9 virulent
races caused 1986
significant crop
losses all the way Example Losses:
from East Africa to Turkey (1992):
South Asia USD$ 568 Million
Iran (1992-94):
USD$ 158 Million

4. Stem Rust Re-emerges Out of Africa
 “Ug99” - Uganda
1998/9. 2007
 Mutating and
migrating (2012: 8
Ug99
races identified in
group, present in 11 2006
Small wheat areas,
countries) small investments in wheat
2006
2009
 Spread throughoutbig global 2005
- but problems!
Africa and into Asia
1998/9 2001
 Further spread is
inevitable 2009
 >80% of global 2009
commercial wheat 2009
cultivars are
susceptible 2000

5. Global Rust Monitoring: The
Catalyst – “Ug99”
 Isolate Ug99 – race
TTKSK
 Unique virulence. Large
% of commercial
cultivars susceptible
 Realization that we need
a global system to
detect and monitor new,
virulent races of wheat
rusts

6. International Rust Monitoring: Stem Rust Model
Country Reports
RustTracker.org
Web portal
To Country
RustMapper
Full GIS
Spatial Database
Winds
Secondary Data
•Relies on national Climate, crops etc
surveillance
•Standard survey
protocols Field survey
•Added value + Trap Nurseries /
•Global Overview Samples plots

7. Response to Ug99: Progress to date
 One of the most successful global
collaborations around a major crop threat
 Global awareness on vulnerability of wheat crop (+
rusts in general)
 Monitoring system in place: current status +
monitoring pathogen populations
 Information systems / tools in place
 International networks emerging, increased national
capacity for surveillance and monitoring
 New sources of resistance identified
 Resistant varieties in seed chain (E.g., Ethiopia
(EIAR/CIMMYT/ICARDA) 8 new rust resistant
varieties; Kenya (KARI/CIMMYT) 8 new rust
resistant varieties during 2010-2012)

8. The Global Surveillance Network
 Transition from data poor to data rich environment
 2007 countries n = 2; 2012 countries n = 28 (12 in Africa)
 Contributing surveys cover about 20% of global wheat
area
2005 2012

9. Status: Pathogen Monitoring
 1999: race TTKSK
“Ug99” identified
 2012: 8 members of
the Ug99 race group
– we know what they
are and where they
are!
 Spread throughout
Africa and into Asia.
Further spread very
likely Ug99 race group is now in 11 countries

10. Changing Pathogen Populations
 2009/2010 Data
 Race TTKSK
(original “Ug99” [red])
only predominates in
Ethiopia
 Other Ug99 race
group races
predominate e.g.,
Sr24 variants

11. Keeping track of “lots” of data
Data management system
– The Wheat Rust
Toolbox (also South Asia
Toolbox) – collaboration
with GRRC and Sathguru
Surveys: 28 countries,
9000+ records
Pathotypes: 21 countries,
1075 isolates

12. Data Management: Wheat Rust Toolbox
NB: Generic - Applicable to all rusts Outputs:
• Survey Mapping
On-line Data Entry
• Pathotypes, +...
Smartphone /
tablet survey
Quality
tool control/publish
User Data Export
Management / Exchange
External Applications
Crop Problem Dbase e.g., RustMapper
(survey, pathotypes, [Trap nursery, Molecular] )

13. Public Information Systems:
WWW Rust Tracker.org
Aim:
 Single source of up-to-date
information for all global wheat rust
monitoring activities
Content:
 Country-specific info: 38 countries
 Dynamic tools – Wheat Rust
Toolbox driven
www.rusttracker.cimmyt.org

14. Rust Tracker.org / Toolbox –
Platform for all rusts
All examples show Yellow Rust
Increased focus on other rusts

15. Summary
 Now have a fully operational global disease monitoring system.
 Surveillance and monitoring network, covering 35 countries and a
large proportion of the developing world wheat area
 Tracked the spread and status of important stem rust races e.g.,
“Ug99 race group".
 A robust and functional data management system - the Wheat Rust
Toolbox - is now in place.
 Global collaboration is ensuring that key databases are shared and
being integrated into different information platforms.
 Monitoring systems, especially in Africa, are critical and have to be
sustained if effective rust control is to be attained.

16. Key Points
 Huge potential to increase African wheat production, but there has
to be a sustained and major effort to ensure that rusts are controlled
and monitored.
 The fight against rusts is not a battle that can be won with a single
round of investments.
 Currently the African wheat area is small and therefore attracts
relatively limited investments. If wheat attains a higher priority more
breeding programs can address rust resistance
 Large wheat areas do NOT automatically equate with increased rust
problems. Current, small areas with little research investment cause
much greater problems
 Sustained, effective rust control & monitoring in Africa would result
in significant global benefits for food security

17. Acknowledgments
 All contributing national partners
 PBI, University of Sydney Donors:
 ICARDA  Bill & Melinda Gates
 CIMMYT Foundation
 AAFC, Canada  DFID
 CDL, Minnesota, USA  USAID
 University of the Free State, South
 IFAD
Africa
 GRRC, Aarhus University,
Denmark
 BGRI / Cornell University