Plant Hormonomics: Multiple Phytohormone Profiling by Targeted Metabolomics.

Area of Science:

• Plant Physiology
• Biochemistry
• Analytical Chemistry

Background:

• Phytohormones are crucial signaling molecules regulating plant development and stress responses.
• Understanding phytohormone dynamics is essential for plant science and agriculture.
• Existing methods often require larger sample amounts or are less comprehensive.

Purpose of the Study:

• To develop a sensitive method for simultaneous targeted profiling of 101 phytohormone-related analytes.
• To quantify endogenous phytohormones in response to salt stress in *Arabidopsis thaliana*.
• To identify key phytohormone metabolites involved in plant salt tolerance.

Main Methods:

• Simultaneous targeted profiling of 101 phytohormone-related analytes.
• Utilized rapid, nonselective extraction and fast one-step purification.
• Employed ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for sensitive quantification.
• Validated the method on salt-stressed and control *Arabidopsis thaliana* seedlings.

Main Results:

• Successfully quantified 43 endogenous compounds in root and shoot samples.
• Demonstrated concurrent quantification of major phytohormone classes (cytokinins, auxins, brassinosteroids, gibberellins, jasmonates, salicylates, abscisates).
• Multivariate statistical analysis and transcriptomic data cross-validation identified key hormones in salt stress adaptation.

Conclusions:

• The developed method enables comprehensive phytohormone profiling from minimal plant material.
• This approach provides valuable insights into plant hormone signaling during abiotic stress.
• The findings contribute to understanding plant adaptation mechanisms and can inform crop improvement strategies.