Interested Members of the University Community are invited to attend the Final Oral Examination for the Degree of Master of Science of Emily Priester of the Department of Plant Agriculture 

Date: Thursday, December 17^th, 2020 
Time: 1:00 PM 

Delivered via Zoom 

To Join the Seminar using Zoom Meeting: 

https://zoom.us/j/92592513254?pwd=SVZ6bnBIcFppbkxxMXpkend4L2h5dz09 

Meeting ID: 925 9251 3254  

Passcode: 397155 

Please contact Emily at eprieste@uoguelph.ca if you wish to be added to the list to attend the examination portion of the defense. 

Thesis Title: Elucidating Resistance Mechanisms in Glyphosate Resistant Populations of Canada Fleabane (Conyza canadensis (L.) Cronq.) 

Advisory Committee
Dr. Francois Tardif, Advisor
Dr. clarence Swantoon
Dr. Eric Page

Examination Committee
Dr. Manish Raizada
Dr. Gale Bozzo
Dr. Francois Tardif
Dr. Eric Page

ABSTRACT 

An analog of glyphosate, glycine, has been shown to be a competitive inhibitor of glyphosate sequestration which could allow separation of target site and non-target site resistance mechanisms. Therefore, the objective was to determine if the addition of glycine to glyphosate would reduce the level of resistance in glyphosate resistant Canada fleabane. Glycine and glyphosate were applied in a hydroponic system with the resistance levels being measured by shikimate accumulation and growth variables. It was found that the addition of glycine caused an increase in the resistance level for the resistance populations of Canada fleabane used. Also, the shikimate accumulation was inhibited by glycine in the susceptible plants at low dose (0.1mM) of glyphosate and at the higher dose (0.2 mM) for the resistant plants. This antagonistic effect observed from the combination treatment was unexpected and may be due to glycine interfering with photosynthesis.