Page 58 - PC2019 Program & Proceedings

PLANT CANADA 2019

PS5. Tuesday, July 9, morning session at 9:20 am

Dr. Clarence J. Swanton, N. Berardi and S. Amirsadeghi

University of Guelph, ON

Plant Competition and the Physiology of Fear

Abstract: Plant competition is recognised as one of the most important biological interactions that
influences plant community structure and individual plant fitness. The competitive interactions for limited
resources of light, water and nutrients are thought to be the primary mechanisms by which plants are harmed.
This presentation will explore an alternative view, a view that suggests that the primary mechanism of plant
competition is the creation of a cellular imbalance. Experimental evidence will be presented to show that
under resource independent competition, far red enriched light reflected from neighbouring weedy plants can
alter the balance between the production of reactive oxygen species and the plant’s ability to detoxify through
antioxidant defence mechanisms. Specifically, the determination of singlet oxygen involvement in early
responses of crop plants to neighbouring weeds changes everything that we know about plant competition. It
also provides a unique opportunity to compare physiological responses of mammals and plants to competition,
hence the “physiology of fear”.

Bio:

Dr. Swanton obtained his BSc in Botany from the University of Toronto, His MSc in Agrometerology from the
University of Guelph, and a PhD in Plant Ecology from the University of Western Ontario. During the years
between earning his MSc and his PhD, he was employed as a field agronomist with the Campbell Soup Company
of Canada and later as a weed biologist with the Ontario Ministry of Agriculture and Food. In 1985 he joined the
University of Guelph as a faculty member in the Department of Crop Science. In 1996 he was promoted to full
professor. From 1998 to 2004, Clarence served as the first Chair of the Department of Plant Agriculture which
included the Departments of Crop Science, Horticulture and the Horticulture Research Institute of Ontario. From
2007 to 2008 he served as President of the Canadian Weed Science Society. He has won numerous awards for
his research. In 2013 he received the Outstanding Canadian Award in the area of Crop Protection from Bayer
CropScience for exceptional contributions to science and innovation. His research is focused on weed ecology
and the development of integrated weed management systems for field and horticultural crops.
https://www.plant.uoguelph.ca/cswanton

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