Page 225 - PC2019 Program & Proceedings

PLANT CANADA 2019

P23. Analysis of Abscisic acid (ABA) accumulation stressed and non stressed Brassicaceae plants
*
Hussain, S. ; E. Nambara; Z. Xu; F. Nguyen
University of Toronto

In order to respond to changing environmental conditions, the survival of crop plants depends on their
ability to mount a whole plant response. Taking these conditions into consideration, our objective is to
determine how abscisic acid (ABA) accumulates in a whole plant in response to water stress, such as
osmotic stress and drought. We investigated the spatial patterns of ABA accumulation in stressed and
non-stressed Brassica napusplants (NAM-0 cultivar). During vegetative growth, ABA levels were
similar across different leaves of non-stressed plants, and osmotic stress induced ABA accumulation in
the leaves whose ABA levels remained consistent across different leaves. During reproductive growth,
ABA levels were highest in younger leaves of non-stressed plants and this pattern was consistent for
stressed plants. The accumulation of ABA in young leaves was seen in both vegetative and reproductive
growth stages showing that the plant prioritizes young leaves over older leaves. Using B. rapa,we also
found that under osmotic stress conditions ABA accumulation increases significantly in whole plants
when compared to non-stressed conditions. This result will allow a comparative study on spatial patterns
of ABA accumulation under stressed and non-stressed conditions.

Saad Hussain (saads.hussain@mail.utoronto.ca)

P24. The Drought Response Syndrome: A complex response mediated by water deficit severity and
time
*
Chen, R. ; J. Sangiovanni; O. Wilkins
McGill University

Drought is a critical factor constraining plant growth and development. Understanding the mechanisms by
which forest trees respond to drought is of paramount importance. In this experiment on how hybrid
poplar respond to different severity of water deficit, we find that poplar has different growth strategies in
different water availability environment by different transcriptome activity. Moreover, samples collected
at different time of day showed that transcription of internal circadian rhythm is predominant and has
great interaction with transcriptome activities from water deficit.

Ruite Chen (ruite.chen@mail.mcgill.ca)

Page 223 of 339