Kenyans help world fight wheat pest

Two Kenyan scientists are among researchers who have developed wheat varieties that could revolutionise production of the crop.

The role of the two in the research has been described at a global workshop as “incalculable.”

Peter Njau, a plant breeder and deputy director of Kenya Agricultural Research Institute, Njoro, and his colleague, Dr Ruth Wanyera, were among key presenters at the Borlaug Global Rust Initiative 2009 Technical Workshop in Mexico recently.

The wheat experts were invited by Nobel Prize winner Norman Borlaug. The four-day conference in Ciudad Obregón, between March 17 and 20, brought together “leading scientists from Australia, Asia, Africa, Europe and the Americas.”

The global experts “reported significant progress in developing new varieties of wheat capable of resisting a virulent form of an old disease that threatens wheat production worldwide,” said the Borlaug Global Rust Initiative.

Dr Njau’s report was “on strate- gies and progress towards development/release of rust-resistant varieties in Kenya.” Dr Wanyera’s presentation was on the field efficacy of fungicides used against stem rust.

Borlaug Global Rust Initiative secretariat director Rick Ward praised the Kenyan researchers. “Peter Njau, Ruth Wanyera and other scientists at Kari’s Njoro Centre play a central role in reducing the world’s vulnerability to stem rust Ug99,” he told The EastAfrican.

He added, “The team helped establish the true magnitude of Ug99’s threat to world food security. It evaluated various wheat varieties in Njoro’s research fields... and worked with breeders to develop the capacity to evaluate 40,000 different wheat varieties annually.

“That capacity is enabling both Kenya and the world to develop resistant varieties. Njoro and Kari staff are world class assets in the battle against Ug99. Kari-Njoro is a partner in Cornell University’s Durable Rust Resistance in Wheat Project, which is funded by the Bill and Melinda Gates Foundation.”

Last year, Dr Njau and his team worked with global experts to test 20,000 wheat lines from more than 15 countries for resistance to Ug99, the most stubborn type of stem rust disease.

Named for its discovery in Uganda 10 years ago, Ug99 is well established in Kenya, where in some areas the reddish, windborne fungus has decimated 80 per cent of wheat fields. The Ug99 was first detected in Uganda in 1998.

It was subsequently detected in Kenya in 2002 and in Ethiopia in 2003, Sudan and Yemen in 2006, and in Iran in 2007.

Stem rust was historically one of the most destructive diseases affecting wheat and barley. Successful control of the disease for over three decades through the use of genetic resistance has resulted in a sharp decline in research recently.

Detection and spread of Ug99 in East Africa is of high significance. A possible migration path of the disease to North Africa through the Arabian Peninsula and then to Middle East and Asia is envisaged.

These areas are highly susceptible to Ug99 and their environment is conducive to disease epidemics. The resurgence signals a breakdown of resistance genes that protect wheat varieties in many countries.