Induction of systemic resistance against tobacco mosaic virus by Ningnanmycin in tobacco.

Ningnanmycin (NNM) is an antiviral agent firstly isolated from Strepcomces noursei var·xichangensisn. Studies have shown that NNM promotes PAL, POD and SOD activity and possesses antiviral activity against tobacco mosaic virus (TMV). In this study, our results demonstrated that NNM inhibited the polymerization process of TMV coat protein (TMV-CP) in vitro and promoted the systemic accumulation of pathogenesis-related proteins (PRs), which are the markers of systemic acquired resistance (SAR). An non-expressor, pathogenesis-related genes 1 (NPR1) that regulates SAR and induces systemic resistance (ISR), increased. In addition, the Jaz3 expression increase showed that NNM also induced ISR. Based on the results of this work and earlier reports, it is suggesting that NNM induces tobacco systemic resistance against TMV via activating multiple plant defense signaling pathways.