A New Mechanism To Destroy The
International Food Security on
the Way …We Must Act Quickly
New Race of Wheat Black
Stem Rust Causal Agent
(Ug99) was Born
Dr.Mohammed AL-Hamdany
Plant Pathologist, Chief Scientific •
Researches
Department Head of Plant Pathology •
Genetics and Plant Breeding Centre •
Ministry of Science and Technology •
Puccinia graminis
1. Has a complex life cycle.
•
2. The pathogen need two •
hosts to complete its life
cycle, Barberry and Wheat.
Puccinia graminis
3.In spring and summer, infections on •
wheat existed as Uredium and
Urediospores
4. Dissemination and spreading of spores
and infections to other wheat plants
either in the same field or other fields,
regions and countries depend on the
environmental conditions and host
reactions (cultivars used).
•
Disease Symptoms and
Signs on Wheat Stems
Alexandria, Egypt. October 9-11, 2006
Life Cycle Stages
1. Basidium from Teliospores (Wheat) •
2. Pycnium from Basidiospores (Barbary) •
3. Aecium following mating** (= = = =) •
4. Uredium from Aeciospores (Wheat) •
5. Telium following Uredium Stage (= = ) •
•
Life Cycle of P.graminis
Uredium & Urediospores on
Wheat Plants
Telial Stage &
Teliospores on Wheat
Infection Process on
Barberry by Basidiospores
Pycnial & Aecial Stages
on Barberry Leaves
Aeciospores Infect Wheat
Only
Uredium & Urediospores On
Wheat Following
Aeciospore Infections
How The Sr Pathogen Cause
Damage on Wheat Plants
Stem rust blocks the vascular •
tissues in cereal grains including
wheat, oats and barley. Unlike leaf
or stripe rusts that may reduce
crop yields, Ug99-infected plants
may suffer up to 100 percent loss.
Sr Damages on Wheat
Pathogen attacks the aboveground
wheat
plants.
•
Infected Plants produced fewer tillers
and set fewer seeds in each
spike
Wheat Plants may die under heavy •
•
Yield Loss In Wheat
Depend on
Pathogen •
Virulence
Susceptible Wheat •
Cultivars
Favourable climate Conditions •
Time
•
Disease Epidemic
Epidemic occur as a •
consequence of growing
susceptible cultivars
Dynamics of rust epidemic •
are very much like those of
FIRE in forest or push fire
Ingredients of Fires (Rust
Epid.)
1. Fuel .. Area & Sus.Cult.,Degree of Sus. •
2. Ignition Points.. Amount of Init. •
Inoculum.
3. Favourable Clim.Cond. .. Temp. & Moist. •
4.Air Movement •
ONE STARTED BOTH ARE DIFFICULT TO •
STOP
Inoculum Income……..
Numbers and Time of the •
Primary Infection Sites Will
Significantly Determine the
Yield Loss in Wheat
Kirby and Archer 1992. Rust Disease of Wheat (CIMMYT Pub.)
Alexandria, Egypt. October 9-11, 2006
Yield losses
Canada:
Control of SR. estimated @.$350
million (can)
(if epidemic similar to 1954)
•
Australia: Yield loss in 1973, $200 •
million (Aus.)
(today eq. $ 1+ billion)
•
USA: Yield loss (MN, ND, SD) in 1904, $10
million (US $)
•
•
•
South Africa: Combined leaf
and stem rust infections of
leading spring variety
SST88 reduced single
plant yield by 43%1990’s
GRI-Alexandria, Egypt. October 9-11, 2006
Race
a group of individuals (Spores, Fungal
structures, cells and particles, etc. ) of a
pathogen having identical genetic
traits with other groups of the same
pathogen BUT its different from the
others in its virulence
•
Virulence and
Aggressiveness
Virulence : Ability of certain pathogen race •
to overcome a certain resistant gene in a
certain cultivar.
Aggressiveness: Ability of Pathogen •
(Race) to cause the highest level of
infection in a shortest time
Resistant Genes in Wheat
Special For P. graminis
The Scientists have been successfully •
identify numerous resistant genes in
Wheat (Sr) following 1954.
Pathogen Races have been overcome •
resistant genes in wheat…Therefore, all
the breeding programs through an
excellent cooperation with the plant
pathologist developed wheat cultivars
carrying resistant genes
Black Stem Rust In Iraq
Since Stem Rust need high temperature (20-25C̊) •
during wheat season in particular during Feb.March which its rarely occurred in Iraq, the
disease was considered as a secondary one.
Therefore, all the activities have been
concentrated on Leaf and Yellow rust diseases
because the environmental conditions during
wheat seasons in Iraq are suitable for primary
infections and disease development
How Did the Ug99(TTKS)
Develop
The Race was first noted in Uganda in 1999 as a
result of new recombination on alternate host.
The race has spread throughout the highlands
of East Africa. In January 2007, spores blew
across to Yemen, and north into Sudan . The
race was reported in Iran Also
The Scientists wrongly thought that Black stem
rust become not frightening disease of wheat
Due to the resistant genes carried by most
wheat cultivars in particular wheat belt regions
in Asia (India and Pakistan) and USA.
Most Landraces Wheat Cultivars in Wheat Belt •
carried Sr31 and Sr24.
Ug99 overcome Sr31&Sr24 •
.
Epidemic Form of P.graminis
in
1950s
New Race of P.graminis (15B) destroyed 40% of spring wheat •
cultivars in USA in 1954.
Norman Borlaug initiated a comprehensive breeding program •
aimed to develop highly resistant wheat cultivars following that
disaster.
The new developed cultivars resist all the population diversity of
P.graminis (existed races) around the world.
•
The resistant reactions in wheat cultivars lasted 45 •
years……Until the appearance of Ug99 which destroyed
every things.
Therefore Ug99 destroyed the infrastructure of
Breeding programs for Black stem rust resistance since
1950s in the last century as Borlaug said.
•
Do We Have Ug99 on
Iraqi Wheat Cultivars
WE DON’T KNOW…….Because We don’t •
Have any wheat cultivar carrying known or
unknown resistant gene or genes as they did in
Uganda, Kenya, Ethiopia ,Yemen and Iran.
Ug99 was discovered in Uganda in 1999 when •
wheat cultivars carrying Sr31 resistant genes
showed susceptible reactions.
Dissemination Path of
Ug99 Urediospores
The governments and the Ministries of •
Agriculture in Uganda and Kenya Ignored the
Scientists warning and refused to set a budget
to study this unusual phenomenon.
Ug99 successfully built its inoculum's units , •
and moved by wind toward the North Eastern
Africa during many seasons.
In January 2007, Urediospores crossrd the red
sea and reached Yemen.
Ug99 reported in Sudan •
In march 2008, Ug99 was detected in western
Iran (Near Iraqi Borders).
•
•
Expected Path of Ug99
Dissemination
Frightening Results
Its estimated that as much as 80% of all wheat
cultivars planted in Asia and Africa showed
susceptible reactions to Ug99.
•
80% of 200 wheat cultivars from USA •
showed susceptible reactions.
Most US Wheat Cultivars (Spring and •
Winter) will be change during the next
four years.
.
The Question in which
its answer threaten us
…
How Did Ug99 Reach
Iran
Possible Ways of
Reaching Iran
1. Through the air currents which carried the •
urediospores of P.stiriiformis in 1990s, from
Yemen-KSA -Syria-Jordan, Iraq and then Iran.
2. By Human (Scientists) during their visit to •
Uganda or Kenya( one Infected Leaf)
3. Contamination of Visitors dresses during •
their walk in rusted field in African Countries.
Meaning of Arriving Iran
Ug99 is Now at the Front Door of The •
Major Wheat Production Areas in Asia,
Which Consist 20-25% of Annual World
Production of Wheat.
Countries east of Iran, like •
Afgan.,India,Pak.,Turkm.,Uzbek., and
Kazak., and all major wheat producers,
are most threatened by Ug99 and Should
be on high alert….
The Ugly Face of Ug99
Ug99 strain found in Yemen was more •
virulent than the one found in East
Africa!!!!!!!!!!.
Ug99 will likely hybridize with P.graminis •
isolates that are native to Iran !!.
Therefore, the isolates coming out of Iran
will probably be different than the
Ug99!!!!!.
International Scientific
Responses
1. Disease surveillance and wheat breeding are already underway
to monitor P.graminis and to develop Ug99 resistant varieties.
•
2. FAO urged countries to increase disease surveillance
and intensify efforts to control the disease.
•
3. Scientists from •
ICARDA,CIMMYT,FAO,Ethiopia,Kenya,Egypt,Yemen,USA and
Canada attended the International Consultation Meeting in Addis
Ababa, 1-3, October,2007. …Establishment of monitoring and
forecasting mechanisms for various races of P.graminis particularly
a very virulent new one (Ug99), Using Geographic Information
System (GIS).
4. Workshop meeting at ICARDA Centre •
in Aleppo, Syria (10-11 march,2008) in a
cooperation with FAO,,CIMMYT and
Cornel University (USA) . Egypt,
Erteria,Ethiopia,Iran,Kenya,Morooco,Nep
al,Pakistan,Sudan,Syria,Turky,Tunisia,Oro
gway, and Yemen were participated.
5. Borlaug Global Rust Initiative
(BGRI)..was established to combat wheat
rust around the world…..
6. BGRI supports countries in developing •
resistant cultivars, producing clean
quality seeds, upgrading national plant
protection and plant breeding services.
7. An early warning system based on FAOs •
Desert Locust information Service could
help forecast the movement of stem rust,
since both locust and Urediospores
follow wind currents .
Scientific Responses…… cont.
8. Global Rust Initiative (GRI), succefully •
identify many wheat genotypes having
resistant reaction toUg99.
9. Most wheat cultivars planted in the •
world were evaluated for disease
response against Ug99 in Kenya and
Ethiopia.
10. Sr2 could be effective resistant gene •
What is The Worrisome
thought
Heavy Storm during Wheat •
season blowing from Yemen
toward India and Pakistan
through Iran. If this frightening
thought really happen, 65 million
hectares of wheat plants will be
completely destroy….
What Can We Do …
1. Scientific faith of the incoming challenge •
2. There is no time for meetings or Arguments •
on the importance of Ug99
3. Visiting Yemen,KSA, Syria, and Iran as soon •
as possible to be a part in any ongoing project
during the incoming season.
4. Evaluate the disease response of all Iraqi •
wheat cultivars along with the promising
genotypes by growing them in Kenya or
.Ethiopia as the others did.
5. All Breeding programs for wheat •
improvement in Iraq must be centrally control
by a scientific committee
6. Establishing wheat traps in different regions •
consist of wheat cultivars carrying Sr genes in
particular Sr31 and Sr24.