Accumulation of feruloyltyramine and p-coumaroyltyramine in tomato leaves in response to wounding

The amounts of two phenolic compounds, E-feruloyltyramine and E-p-coumaroyltyramine, increased 10-fold in tomato leaves in response to mechanical wounding, and 25-fold in response to the oligosaccharide elicitor chitosan. Using fluorescence detection, feruloyltyramine was shown to accumulate in response to wounding, but not to jasmonic acid or systemin, two elicitors of systemic wound-inducible defense responses in tomato. Feruloyltyramine also accumulated in leaves of mutant tomato plants deficient in the octadecanoid signaling pathway in response to wounding, indicating that its synthesis is not regulated through this pathway. These data support a role for hydroxycinnamate-tyramine conjugates as part of the array of defense chemicals and protective biopolymers induced in leaves and other plant tissues by wounding, to protect the plants against pathogen and herbivore attacks. (C) 1997 Published by Elsevier Science Ltd. All rights reserved.