Photo of Jacqueline Bede

Jacqueline Bede

Associate Professor

Office:Department of Plant Sciences, McGill University

Dr. Bede’s research focuses on plant-insect interactions, specifically how plants regulate their
defenses to act rapidly and effectively against the insect and also how the insect herbivore
manages to circumvent plant defenses. One aspect of this research is the investigation of
plant oxidative stress responses to herbivory. Caterpillars of the beet armyworm,
Spodoptera exigua, have labial salivary effectors, such as glucose oxidase, that are believed
to suppress induced plant defenses. As glucose oxidase produces hydrogen peroxide
(H202), Dr. Bede has investigated the role of caterpillar labial saliva in changing the plant foliar
redox balance. Dr. Bede is interested in caterpillar labial saliva-associated changes in plant
protein post-translational modifications, particularly in cysteine oxidation.

Recently, Dr. Bede’s lab has begun to investigate the effect of climate change, specifically carbon
dioxide (CO2) on the plant’s ability to mount an effective defense response. Our early
research has shown that at elevated CO2, there is a suppression of a wound-induced
jasmonate burst in well nitrate fertilized plants (Paudel et al., 2016). Dr. Bede’s lab has recently
published a paper comparing different nitrogen fertilizers (nitrate vs ammonium) to
understand the underlying mechanism (Martinez-Henao et al., 2019). Jasmonate levels are
lower and wound-induce JA-Ile levels in well-nitrogen fertilized plants are attenuated at
elevated CO2. We are continuing to investigate the role of photoperiod, photorespiration,
nitrogen metabolism in this suppression of jamonate responses.