ProMED-mail is a program of the
International Society for Infectious Diseases
May 15, 2006
Source: Dailytimes.com.pk [edited]
Pakistan, India could suffer drastic fall in wheat output due to
Wheat producing countries, including Pakistan and India, may
suffer a drastic decline in production due to a new kind of
rust, which has recently been found in an African country and
which is heading towards South Asia, an international
agriculture expert told the Daily Times on Saturday [13 May
Existing varieties of wheat are highly susceptible to the rust,
found in wheat crops in the East African countries of Tanzania
The rust, which is similar to that found in Uganda, has been
found in the coastal areas of Sindh. The new rust could deprive
each wheat producing country of over 50 or even 55 percent of
production of food grain in the years to come.
The expert was of the view that it would take at least 8 or 9
years to develop a new infection-resisting variety of wheat.
According to initial assessments, the rust could greatly damage
crops wherever it goes. The rust is transmittable through air
[by spores - Mod.JAD], and it would largely depend on wind
direction. If the air was directed eastward from African
countries, it would be a major challenge for Pakistan and India,
which are among the big producers of wheat.
The new infection could damage wheat in the next season if it
penetrated northern parts of the country, especially Punjab.
Most Indian wheat is grown in Punjab. Last year , the
wheat production of the country stood at around 21.6 million
tons. If the rust was found in other parts of the country, then
the production could be over 50 [percent] less than the average
wheat production of the country.
According to the expert, currently no variety of wheat is
resistant to the new infection. Rust is not new. It is an old
phenomenon, but the real problem is that the new infection is to
be defeated [can only be managed] by developing a new variety.
Currently, all the varieties are susceptible varieties and do
not have the ability to retard fungal growth.
[Byline: Fida Hussain]
[The cereal crop plant wheat (bread wheat, _Triticum aestivum_
and durum wheat, _Triticum turgidum_) develops symptoms of stem
rust when infected with the fungus _Puccinia graminis f.sp.
tritici_. Severe losses due to wheat stem rust have been held at
bay worldwide due to effective resistance breeding.
A strain of stem rust, now called Ug99, was found in Uganda in
1999, and it has since spread to Kenya and Ethiopia. It is
thought to have the potential to seriously damage wheat
production there and elsewhere. This is because it can overcome
resistance in wheat offered by the commonly deployed Sr31 gene.
Great concern has been expressed over the consequences of this
strain reaching Asia, and the current report seems to indicate
that this may have happened. This report is not sufficiently
clear on the true identity of the strain mentioned, but the
information provided suggests the newly detected stem rust
infections in the coastal areas of Sindh, Pakistan could be
Ug99. If correct, this is a significant finding and will have to
be followed carefully since most articles on this strain suggest
it could cause a global food crisis.
It has not reached the main wheat production areas of Pakistan
in the Punjab, but it is worth noting that wheat accounts for 60
percent of the calories and more than 40 percent of the protein
in the average daily diet of that country by some estimates.
About 70 percent of U.S. wheat varieties are thought to be
susceptible to Ug99. Between 70 and 75 percent of wheat grown in
India and Pakistan are also susceptible to this rust, and wheat
in Egypt and China is thought to have similar vulnerabilities.
In an earlier 2006 posting (20060406.1039), concerns were raised
that current (2006) ongoing initiatives to import wheat to India
could lead to the introduction of new pathogens such as Ug99.
There is no indication that importation has played any part in
this outbreak of stem rust in Pakistan. This report will help
intensify ongoing efforts to select or breed new wheat varieties
resistant to Ug99.
Addressing the potential issues raised in this posting is the
purpose of the Global Rust Initiative (see link), which has as
its mission the systematic elimination of the world's
vulnerability to the stem rust race Ug99.
Sindh, SE Pakistan:
[see also in the
Stem rust, wheat - multicountry: new strains 20060406.1039
Cereal rust update - USA 20060322.0895
Wheat stem rust, Ug99, new strain - East Africa 20050928.2849
Wheat stem rust, new strain - Uganda 20050912.2698 2000
Wheat stem rust in resistant wheat lines - Uganda 20000702.1092]