Scientists aim to cut risk posed by Ug99 to wheat supplies
lines resistance to a stem rust fungus, which is threatening crop
and adding to existing problems of rising costs and a 30-year low
for stockpiles.
Ug99, the fungus, was identified in 2005. It spread from Africa by wind-blown fungal spores and has overcome most of the stem rust resistance genes bred into wheat varieties during the past few decades. The Agricultural Research Service, the USDA's scientific agency, will this autumn release the first wheat lines pyramiding two or more genes for resistance to Ug99. It will become available as a speciality wheat for eastern US to be used alongside other lines to develop new commercial varieties and high yield and Ug99 protection. The search for resistance began in response to agronomist and Nobel Peace Prize winner Norman Borlaug request. He considers the disease the most serious threat to wheat and barley in 50 years. Bread wheat has been determined as being the most vulnerable class of wheat. Protecting against Ug99 The ARS has dedicated a team of scientists to tackle areas aspects of Ug99, after the disease has had a destructive effect on crops in Uganda and nearby African countries. The team is collaborating with researchers from across the country and around the world to find solutions to a problem they have said poses a "massive threat to a global food staple". Its priorities are determining American wheat and barley vulnerability to Ug99, identifying new sources of genetic resistance, discovering molecular markers to speed up breeding for protection, developing swift detection methods, and establishing nationwide surveillance for the disease. Internationally, ARS has also provided funds and expertise to the Global Rust Initiative formed in 2005 by two international organisations to fight the new strain of the disease. Dwindling wheat supplies Wheat is the second most produced food among the cereal crops, and supplies have begun to dwindle as demand continues to outweigh production. Additionally prices are increasing because of worldwide economic growth, weather conditions, energy prices, export restrictions, as well as new markets for alternative fuels. According to the HGCA Knowledge Centre, weather reduced wheat production by 20 metric tonnes, to a level below demand between 2007 and 08. Recent floods in Iowa will have further threatened wheat stocks as they crops were damaged along with corn, oats, rice, soybean and other food commodities.
