Isolation of jasmonate-induced sesquiterpene synthase of rice: Product of which has an antifungal activity against Magnaporthe oryzae

Rice is one of the most important crops worldwide, and it is a model for molecular studies of monocotyledonous species, particularly for understanding the molecular mechanisms of plant disease resistance. Jasmonic acid (JA) is an important plant hormone involved in rice-pathogen interactions. In addition, JA-induced volatiles are known to be involved in the rice defense system regulated by JA signaling. In this study, we isolated a JA-induced terpene synthase from rice, and found that it produces two sesquiterpenes; beta-elemene and beta-bisabolene. Furthermore, beta-elemene exhibited significant antifungal activity against Magnaporthe oryzae; however it did not exhibited any antibacterial activity against Xanthomonas oryzae pv. oryzae. JA-induced accumulation of beta-elemene was regulated by OsJAZ8, a rice jasmonate ZIM-domain (JAZ) protein that is involved in the JA signaling pathway, suggesting that beta-elemene plays an important role in JA-induced resistance, and that it functions as an antifungal compound in rice. (C) 2014 Elsevier GmbH. All rights reserved.