Nitric oxide as a bioactive molecule in the regulation of chalcone synthase during jasmonic acid mediated defense signaling in ginger

Nitric oxide (NO) and elicitors have been found to enhance the defense responses in plants. In this study, the role of NO in the regulation of chalcone synthase (CHS) gene during jasmonic acid (JA)-mediated defense response under wound stress in ginger were investigated. It was observed that NO is responsible for the up-regulation of CHS during wound stress, which further stimulates the JA-mediated stress responses. Confocal microscopy and qRT-PCR were used to study the accumulation of NO and CHS (ZoCHS) transcript levels, respectively, at the wound site. Relative expression of ZoCHS was found to increase by double fold in wounded plants upon treatment with NO and JA. Confocal studies confirmed the accumulation of NO at the wound sites which further triggered the JA-mediated stress responses. Overall results in this work implicate the role of NO in positive modulation of JA defense signaling responses and expression of CHS in ginger during wounding. These findings will help in the development of plants with improved metabolic and defense traits.