An Analytical Method to Quantify Three Plant Hormone Families in Grape Berry Using Liquid Chromatography and Multiple Reaction Monitoring Mass Spectrometry

Hormones play an important role during the development and ripening of grape berry. Unlike the case of ethylene in climacteric fruits, several different hormones are believed to sequentially accumulate at specific times during berry developmental stages to promote different physiological processes. To dissect this complex hormonal interaction system in a recalcitrant tissue containing several interfering compounds including sugar and phenolic compounds, an extraction protocol and an LC-MS-based analytical method that includes three hormone families have been adapted. Using this technique, we optimized a method to simultaneously detect and quantify cytokinin, auxin, and abscisic acid-related analytes in grape berries across the developmental stages and between tissues. Resulting quantifications of the analytes are consistent with the overall trend of the ABA, auxin, and cytokinin dynamics in grape and reveal new patterns not previously reported in this plant. Evolving evidence of coordinated action of several hormones during the critical phases of berry development (cell division, cell expansion, berry ripening) suggests a need to further integrate other plant growth regulator families to provide a more comprehensive picture.