22 May, 2023
Researchers have cloned the wheat rust resistance genes Lr9 and Sr43 and identified that they encode unusual kinase fusion proteins. Their research will enable new options for addressing resistance to disease in bread wheat.
Each year about 20 percent of global wheat production is lost to pests and disease, the equivalent of 3,500 grain ships. Breeding resistant cultivars is one of the most economical and environmentally friendly ways to address the problem.
The wild relatives of wheat provide a reservoir of genetic diversity for crop improvement. The Lr9 leaf rust resistance gene, for example, was originally identified in a wild goatgrass (Aegilops umbellulata). In a pioneering experiment conducted in the 1950s, Dr Ernest Sears succeeded in transferring a tiny Lr9-carrying segment of an Aegilops chromosome into bread wheat, demonstrating that it is possible to stably cross small chromosome segments from distant wild relatives.