Abstract
Plants are exposed to various stresses, such as pathogen attacks and environmental stress. To adapt to the stressful environment, plants have evolved unique self-protection systems. In plants, salicyclic acid (SA), jasmonic acid (JA) and abscisic acid (ABA) play important roles in adaptation to biotic and abiotic stresses. In addition, recent studies have shown that each plant hormone is mutually antagonistic interactions in complex networks of various signaling pathways. For instance, it has revealed that treatment with ABA suppresses the induction of systemic acquired resistance (SAR) by inhibiting the pathway both upstream and downstream of SA, independently of the JA/ethylene-mediated signaling pathway. Conversely, the activation of SAR suppresses the expression of ABA biosynthesis-related and ABA-responsive genes. These results show that antagonistic crosstalk occurs at multiple steps between the SA-mediated signaling of SAR induction and the ABA-mediated signaling of environmental stress responses. Here, we will discuss that involvement of plant hormones and plant hormone mediated-gene expression in SA-, JA- and ABA-treated leaves.
