Spectroscopic sensitivity of real-time, rapidly induced phytochemical change in response to damage
Article first published online: 5 FEB 2013
© 2013 The Authors. New Phytologist © 2013 New Phytologist Trust
Volume 198, Issue 1, pages 311–319, April 2013
How to Cite
Couture, J. J., Serbin, S. P. and Townsend, P. A. (2013), Spectroscopic sensitivity of real-time, rapidly induced phytochemical change in response to damage. New Phytologist, 198: 311–319. doi: 10.1111/nph.12159
- Issue published online: 25 FEB 2013
- Article first published online: 5 FEB 2013
- Manuscript Accepted: 26 DEC 2012
- Manuscript Received: 4 SEP 2012
- NASA. Grant Number: NNX10AJ94G
- Graduate School and College of Agriculture and Life Sciences
- Asclepias syriaca (common milkweed);
- partial least-squares regression (PLSR);
- phytochemical induction;
- An ecological consequence of plant–herbivore interactions is the phytochemical induction of defenses in response to insect damage. Here, we used reflectance spectroscopy to characterize the foliar induction profile of cardenolides in Asclepias syriaca in response to damage, tracked in vivo changes and examined the influence of multiple plant traits on cardenolide concentrations.
- Foliar cardenolide concentrations were measured at specific time points following damage to capture their induction profile. Partial least-squares regression (PLSR) modeling was employed to calibrate cardenolide concentrations to reflectance spectroscopy. In addition, subsets of plants were either repeatedly sampled to track in vivo changes or modified to reduce latex flow to damaged areas.
- Cardenolide concentrations and the induction profile of A. syriaca were well predicted using models derived from reflectance spectroscopy, and this held true for repeatedly sampled plants. Correlations between cardenolides and other foliar-related variables were weak or not significant. Plant modification for latex reduction inhibited an induced cardenolide response.
- Our findings show that reflectance spectroscopy can characterize rapid phytochemical changes in vivo. We used reflectance spectroscopy to identify the mechanisms behind the production of plant secondary metabolites, simultaneously characterizing multiple foliar constituents. In this case, cardenolide induction appears to be largely driven by enhanced latex delivery to leaves following damage.