2006 Volume 23 Issue 3 Pages 321-327
To develop a screening system for plant activators, which are novel substances that protect plants by enhancing their inherent disease-resistance mechanisms, we utilized a GUS reporter gene system using promoters of the defense-related genes, PR-1 and PR-4. To validate the strategy, we performed subsequent analysis using an Arabidopsis microarray consisting of 1200 full-length cDNA clones representing putative defense-related and regulatory genes. Benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester and 2,6-dichloroisonicotinic acid activated plant defense responses via the salicylic acid (SA)-dependent signaling pathway, and β-aminobutyric acid triggered a primed state in the plant that enables more efficient activation of the SA-, jasmonic acid- and ethylene-signaling pathway. These results suggest that this novel system can be used to screen for candidate plant activators.
