Washington, Mar 13 : A fungus that is deadly for wheat may already have reached Pakistan two years earlier than predicted, and may soon reach the vital Punjab region, warn researchers.
The killer fungus, called Ug99, is a virulent strain of black stem rust (Puccinia graminis).
First identified in Uganda in 1999, it has since invaded Kenya and Ethiopia and, last year, Yemen. ick Ward of CIMMYT, the wheat breeding institute in Mexico that started the Green Revolution, revealed what made it easier for the fungus to spread.
"It turns out most of Kenya was planted with a wheat variety that contained only one gene for rust resistance, SR24," the New Scientist quoted him, as saying.
This gave Ug99 strains resistant to SR24 an upper hand. When farmers switched to using wheat with other resistance genes, the fungus became resistant to them too.
Based on earlier fungal invasions, scientists had expected prevailing winds to carry Ug99 spores to Egypt, Turkey and Syria, and then east to Iran, a major wheat-grower, getting them some time.
However, with Cyclone Gonu hitting the Arabian peninsula on 8 June 2007, the fungus reached Iran a year or two earlier.
Now, researchers fear that the winds could also have blown the fungus' spores into Pakistan, which lies north of Yemem, and unfortunately where it became difficult to keep track of it's spread.
What makes the situation worse is that Ug99 is now resistant to the three major anti-rust genes used in nearly all the world's wheat.
Though scientists hope to slow the fungus' spread by spraying fungicide or even stopping farmers from planting wheat in the spores' path, the only real remedy remains new wheat varieties that resist Ug99.
However, researchers warn that these may not be ready for five years.
"People will start starving if Ug99 cuts harvests enough to push up grain prices," warns Ward.