The quantification of SA and SA glucoside (SAG) was performed as described previously with a minor modification (Seo et al. 1995 (link)). Briefly, three leaf disks were frozen and ground using liquid nitrogen. SA and SAG were extracted with 90% methanol, and SAG was converted to SA by β-glucosidase treatment. After separation by HPLC (Shimadzu) with an ODS column (μ-Bondasphere C18, 150 mm�ID3.9 mm, 5 μm, 100A; Waters), SA levels were determined using a fluorescence detector (RF-20A; Shimadzu) with an excitation wavelength of 313 nm and an emission wavelength of 405 nm.
JA quantification was performed as described previously (Kojima et al. 2009 (link), Shinozaki et al. 2015 (link)). Briefly, leaf samples (one leaf per sample) were frozen and ground using liquid nitrogen, and freeze dried. JA was extracted and determined using an ultra-HPLC-Q-Exactive™ system (Thermo Scientific) using an ODS column (AQUITY UPLC BEH C18, 1.7 μm, 2.1�100 mm; Waters) as described (Shinozaki et al. 2015 (link)).
JA quantification was performed as described previously (Kojima et al. 2009 (link), Shinozaki et al. 2015 (link)). Briefly, leaf samples (one leaf per sample) were frozen and ground using liquid nitrogen, and freeze dried. JA was extracted and determined using an ultra-HPLC-Q-Exactive™ system (Thermo Scientific) using an ODS column (AQUITY UPLC BEH C18, 1.7 μm, 2.1�100 mm; Waters) as described (Shinozaki et al. 2015 (link)).