Science News 21/04/2011

New research aims to combat global fungi epidemic that threatens food supply and forests

“Rusts,” a group of fungi that attack and damage plants and trees, cost the international agriculture and forestry sectors billions of dollars in lost revenue every year, with an estimated loss of $200 million a year due to the destruction of cereal crops in Canada.

The Economist called wheat rusts the “polio of agriculture” for their ability to spread globally and wipe out food supplies, and their potential to effect global food security. These pests have become highly adaptive against efforts to kill or manage outbreaks and are able to move rapidly from one country to another. Some rust fungi are now morphing into “super pathogens” that could threaten food supplies and ecosystems.

Two BC researchers are using the power of genomics to crack the mystery of what makes rust fungi such powerful and adaptive pests. Dr. Richard Hamelin of the UBC department of Forest Sciences and Natural Resources Canada (NRC) and Dr. Guus Bakkeren from Agriculture and Agri-Food Canada, are working together to learn more about the molecular and genetic interactions between rust fungi and their hosts; the plants and trees.

With support from Genome BC, NRC’s Genomics Research and Development Initiative and the Ontario Ministry of Research and Innovation, their goal is to identify genes that control how rust fungi infect plants and hosts, and which genes in the host can help fight rusts. These efforts will help end-users in the agriculture and forestry sectors plan and treat rust fungi epidemics and breed rust-resistant crops.

“We’re focusing on the poplar tree, a cornerstone of the pulp industry in Canada and a critical source for biofuel and carbon sequestration, and on wheat which contributes over
$4 billion dollars annually to the Canadian economy,” says Dr. Hamelin. “We’ll search for key proteins that allow these rust fungi to evade the host’s defense genes or become resistant to pesticides,” says Hamelin.

To identify these genes, Drs. Hamelin and Bakkeren will infect different wheat and poplar varieties with various rust fungi in a laboratory setting. They will then use new genome sequencing technologies to identify and compare the genes activated during the infection process. The final step will involve developing screening tools for forestry and agriculture, which should appear in the market in two to three years.

“Genomics is providing a 21st century solution for an age-old problem,” says Dr. Alan Winter, President and CEO of Genome BC. “With the sophistication provided by genomics-based tools, solutions to issues in food and fuel production are within our grasp.” Genome BC has funded this project through its Strategic Opportunities Fund, which focuses on projects with direct impact on industry and other end-users.

“Since WWII, breeders have been working on rust resistance, but with genomics we can examine all the genetic information of these rust fungi. This speeds up our understanding of how they interact with host resistance genes and how we might be able to fight them off,” says Dr. Bakkeren. The project will also look at predicting when these fungi will evolve new harmful genes so that breeders can take action, a kind of “early-warning system” that could save forest and wheat crops.

As rust fungi are known to spread from country to country, this project holds the promise of not only protecting Canada’s precious forestry and agriculture supply, but those in other countries as well.

di S. C.