Jasmonic acid (JA) and salicylic acid (SA) are plant hormones involved in plant growth and development. Recent studies demonstrated that presence of a complex interplay between JA and SA signaling pathways to response to pathogenesis attack and biotic stresses. To our best knowledge, no method has existed for simultaneous analyses of JA, SA, and their related compounds. Especially, the glucosides are thought to be the storages or the inactivated compounds, but their contribution should be considered for elucidating the amount of the aglycons. It is also valuable for measuring the endogenous amount of phenylalanine, cinnamic acid, and benzoic acid that are the biosynthetic intermediates of SA due to the existence of isochorismate pathway to synthesize SA. We established this method using deuterium labeled compounds as internal standards. This is the first report of simultaneous analysis of endogenous JA, SA, and their related compounds. Measuring the endogenous JA, SA, and their related compounds that had been accumulated in tobacco plants proved the practicality of the newly developed method. It was demonstrated that accumulation of JA, SA and their related compounds were induced in both case of TMV infection and abiotic stresses.

Theobroxide has been isolated from culture filtrates of Lasiodiplodia theobromae as a potato tuber-inducing compound. In this study, the metabolism of theobroxide was investigated using cowpea as an experimental model and [ 2 H 3-7]theobroxide as a substrate for analyzing a metabolite, which revealed that theobroxide applied exogenously to the roots was converted into 3-O--D-glucopyranosyltheobroxide.