Stephen Wright, associate professor of ecology & evolutionary biology, has won a prestigious NSERC E.W.R. Steacie Memorial Fellowship for his pioneering research in the emerging field of evolutionary genomics.
Up to six Steacie Fellowships are awarded annually to enhance the career development of outstanding and highly promising scientists and engineers.
Upping the fight against herbicide-resistant ‘super weeds’
Herbicide-resistant weeds are becoming a growing threat to global food security and the livelihood of millions of farmers. At issue are the evolutionary characteristics that allow some weed species to rapidly evolve so that the “fittest” survive, regardless of the herbicide used.
Understanding how and why resistance evolves requires scientists with a rare combination of talents in genomics, plant science and computational biology. Stephen Wright, associate professor in the Department of Ecology & Evolutionary Biology (EEB) at U of T, is such a scientist. Having just gained tenure in 2011, Wright is already internationally recognized as one of the world’s most influential scientists in the emerging field of evolutionary genomics.
Wright’s research has provided unprecedented insights into the structure, function and evolution of the genome—knowledge he is currently using to understand how weeds become resistant to herbicides.
“This fellowship highlights the remarkable research environment at U of T, where I have the tremendous opportunity to work with many fantastic students, postdoctoral fellows and colleagues in the Department of Ecology and Evolutionary Biology,” said Wright. “It will enable focused time and resources to launch our group into a number of new directions, including the evolutionary genomics of herbicide resistance.”
Wright and his team have shown that the pace of genome-wide adaptation occurs at a much higher rate than previously thought. Several studies published by his team over the last three years provide the first solid molecular evidence to support a theory biologists have long promoted: species that reproduce sexually (by exchanging genetic material), rather than asexually (reproduction via cloning) or via self-fertilization (when plants acts as both mother and father to their own seeds) are genetically healthier over time. The results suggest that many important crop species are more likely to go extinct in the face of environmental change.
Wright and his colleagues recently addressed one of the longest-standing mysteries in evolutionary biology: why genetic variation for traits in some species can be observed despite the expectation that natural selection will remove most variation. In a report published in Proceedings of the National Academy of Sciences last fall, the team – led by recent U of T doctoral student Emily Josephs, Wright and fellow EEB professor John Stinchcombe – identified an important role for recurring harmful mutations in maintaining genetic variation by examining a single, large population of the plant Capsella grandiflora.
“While the mutations are harmful in the present environment, they may become important sources of adaptation when environments change. Because the mutations enable genetic variation, they are theoretically responsible for ensuring adaptation over time,” Wright said. “This possibly explains how some weeds, especially those that are sexual and have large populations, are able to evolve and survive, despite attempts to eradicate them.”
To date, Wright has published 75 peer-reviewed journal articles, garnering over 4,600 citations. His accomplishments were recognized in 2006 with the prestigious Alfred P. Sloan Research Fellowship in Computational and Evolutionary Molecular Biology. His resources and methods are now widely used in both basic and applied research.
With files from NSERC