Page 63 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

Tuesday, July 9

Dr. Sara Martin
Agriculture and Agri-Food Canada

“Changing Environment, Changing Genes:
Insights from Weed Genetics and Genomics”

Abstract: We are privileged to be living through
this era of biology. Our ability to sequence
genomes is tantamount to a superpower that
allows us to reconstruct an organism’s
evolutionary history, and even to observe as it
continues to evolve. This was very publicly
illustrated during the COVID-19 pandemic when
evolutionary questions such as "where did the
virus originate? what do these mutations in a genomes mean?" were of intense public
interest. Our ability to rapidly sequence genomes meant that scientists were able to
answer the first question, and the massive amount of data collected will help us answer
the second. The genomic data clearly showed the diversity of SARS-CoV-2 variant
changing in response to inadvertent selection stemming from changes in human
behavior, such as the rollout of vaccines and anti-viral treatments. What we see
resulting from these kinds of treatments generally, however, is growing resistance to
chemical control in bacteria, fungi, arthropods and plant species. Compared to the acute
challenge of the SARS-CoV-2 virus, these are chronic challenges that receive less
attention, but that are likely to be more costly in the long term. For example, estimates
have suggested that a loss of chemical controls could halve agricultural production.
While weed genomics doesn’t yet have the epistemic foundation that virologists can rely
on, we are building this foundation quickly. Sequencing genomes allows us to help
address the chronic challenge of herbicide resistance by improving our ability to: detect
target site mutations; determine the genetic basis of non-target site mutations; and
predict future evolution by understanding past evolution and current connections among
populations. These genomes will provide the foundational data for new tools that will
allow us to understand the consequences of mutations and of key genetic pathways that
could be disrupted by new chemical controls. Plant genome sequences are the key to
making progress in the face of the chronic challenge of herbicide resistance, just as the
sequencing of the SARS-CoV-2 genome was key to overcoming the pandemic.

Bio: Dr. Sara L. Martin is a research scientist at Agriculture and Agri-Food Canada’s Ottawa
Research and Development Centre. She holds a B.Sc in Botany from the University of Toronto
and a Ph.D. in Integrated Biology from the University of Guelph. Her research program’s
mandate is to develop our understanding of how gene flow between crop and wild species could
lead to transgene escape, with a secondary focus on the evolution and spread of herbicide
resistance in weeds. As a result, her work ranges from field work to document the current
geographic range of species, to greenhouse work creating hybrids, to the assembly, analysis
and use of plant genomes. Her work has investigated kochia, fleabane, ragweed, wild mustard,
cleavers, and the wild relatives of Camelina.

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