Poster: Secondary Metabolism

Abs # 303: The effect of defense signaling molecules on the content of 2-phenylethyl glucosinolate in Nasturtium officinale R. Br.

Presenter:	Wong, Lynette Y., lwong@biosci.cbs.umn.edu
Authors	Wong, Lynette Y. (A)   Cohen, Jerry D. (A)   Gardner, Gary  (A)   Markhart, Albert  (A)
Affiliations:	(A): University of Minnesota

The Brassicaceae family contains glucosinolates, naturally occurring secondary compounds that function to defend against herbivore and pathogen attack. Nasturtium officinale R. Br (watercress) is a rich source of 2-phenylethyl glucosinolate (gluconasturtiin), and the isothiocyanate hydrolysis product of gluconasturtiin has been implicated in plant defense responses to fungal and pathogen attack as well as in the prevention of certain human cancers. Our previous research indicated that water deficit can increase the level of gluconasturtiin in watercress and that increasing the number of cycles of water deficit further increased the levels of gluconasturtiin. Such a response to an environmental factor has led us to characterize the molecular nature involved with a gluconasturtiin defense reaction. Abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) have been shown to be important signaling molecules involved in regulation and response to abiotic and biotic stresses, and others have shown that SA treatment increased the concentration of 2-phenethyl glucosinolate in leaves of Brassica napus L. A comparison of the accumulation of gluconasturtiin following single or multiple treatments of ABA, JA, or SA on watercress will be presented. Supported by the SOTA TEC Fund of the Blandin Foundation and the Minnesota Agricultural Experiment Station.