Host: The Japanese Society of Plant Physiologists
Pages 0091
Systemic acquired resistance (SAR) is a potent innate immunity system in plants that is effective against a broad range of pathogen. SAR development in plants is mediated by salicylic acid (SA). Here, using different types of SAR-inducing chemicals, i.e., 1,2-benzisothiazol-3(2H)-one1,1-dioxide (BIT) and benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) that act on upstream and downstream of SA in the SAR signaling pathway, respectively, we show that treatment with abscisic acid (ABA) suppresses the induction of SAR in Arabidopsis. Analyses using several mutants in combination with these chemicals revealed that ABA suppressed SAR induction by inhibiting the pathway both upstream and downstream of SA, independently of the jasmonic acid/ethylene mediated signaling pathway. Suppression of SAR induction by the NaCl-activated environmental stress response proved to be ABA dependent.
