Dave Hodson1 and Kumarse Nazari2

1CIMMYT-Ethiopia Email: d.hodson@cgiar.org

2ICARDA Email: k.nazari@cgiar.org

Rust Bowl or Breadbasket?

Keeping track of wheat rust

pathogens in Africa

Africa: Critical for Global Rust Control

“The kitchen where the pathogen is cooked” P. Njau, KARI

Key Driving Factors:

Continuous wheat : Green bridge

Genetic uniformity of commercial cultivars

High elevation/high UV radiation (increased mutations). Wide range of environments

Alternate hosts? E.g., Berberis holstii

“rust is a shifty, changing, constantly evolving

enemy. We can never lower our guard .” EC

Stakman, 1937.

BUT WE DID LOWER OUR GUARD! Rust research

was forgotten in East Africa 1980’s - 2000

Out of Africa?: Dangerous Exports

East Africa is a center for new emerging rust races (Yr9, Ug99 etc).

Mid 80’s to mid 90’s - Yr9 virulent races caused significant crop losses all the way from East Africa to South Asia

Yr9

1986

1994/5

1993/4 1992/3 1991

1991

1986

1995/6

Example Losses:

Turkey (1992):

USD$ 568 Million

Iran (1992-94):

USD$ 158 Million

Stem Rust Re-emerges Out of Africa

“Ug99” - Uganda 1998/9.

Mutating and migrating (2012: 8 races identified in group, present in 11 countries)

Spread throughout Africa and into Asia

Further spread is inevitable

>80% of global commercial wheat cultivars are susceptible

Ug99

1998/9

2007

2006

2005

2001

2006

2000

2009

2009 2009

2009 Small wheat areas, small investments in wheat

- but big global problems!

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

Spatial Database

Secondary Data

Climate, crops etc

International Rust Monitoring: Stem Rust Model

Trap Nurseries /

plots

Country Reports

To Country

•Relies on national

surveillance

•Standard survey

protocols

•Added value

•Global Overview

Field survey

+

Samples

RustTracker.org

Web portal

RustMapper

Full GIS

Winds

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)

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

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

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

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

Data Management: Wheat Rust Toolbox

Crop Problem Dbase

(survey, pathotypes, [Trap nursery, Molecular] )

User

Management

Quality

control/publish

Data Export

/ Exchange

On-line Data Entry

External Applications

e.g., RustMapper

Outputs:

• Survey Mapping

• Pathotypes, +...

NB: Generic - Applicable to all rusts

Smartphone /

tablet survey

tool

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

Rust Tracker.org / Toolbox –

Platform for all rusts All examples show Yellow Rust

Increased focus on other rusts

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.

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

Acknowledgments All contributing national partners

PBI, University of Sydney

ICARDA

CIMMYT

AAFC, Canada

CDL, Minnesota, USA

University of the Free State, South

Africa

GRRC, Aarhus University,

Denmark

BGRI / Cornell University

Donors:

Bill & Melinda Gates

Foundation

DFID

USAID

IFAD