Phytohormone profiling of the sweet orange (Citrus sinensis (L.) Osbeck) leaves and roots using GC-MS-based method

J Plant Physiol. 2016 Jul 20:199:12-17. doi: 10.1016/j.jplph.2016.04.005. Epub 2016 May 17.

Abstract

Phytohormones mainly affect plant development and trigger varied responses to biotic and abiotic stresses. The sensitivity of methods used to profile phytohormones is a vital factor that affects the results. We used an improved GC-MS-based method in the selective ion-monitoring (SIM) mode to study the phytohormone profiling in citrus tissues. One extraction solvent mixture and two derivatization reagents were used, methyl chloroformate (MCF) and N-Methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA). The method showed a low limit of detection and low limit of quantification with high extraction recovery percentage and reproducibility. Overall, we detected 13 phytohormones belonging to six different groups. Auxins, SAs, tJA, and ABA were detected after derivatization with MCF while cytokinins and GAs were detected after derivatization with MSTFA. Cytokinins, SAs, and gibberellins were found in all tissues while auxins and tJA were observed only in the leaves. ABA was found in leaves and roots, but not in root tips. The method we used is efficient, precise, and appropriate to study citrus phytohormonal profiles to understand their crosstalk and responses to environmental and biological stresses.

Keywords: Abscisic acid (ABA); Auxins; Citrus; Gibberellins (GAs); Phytohormone profiling; Salicylic acid (SA).

MeSH terms

  • Acetamides / chemistry
  • Citrus sinensis / metabolism*
  • Fluoroacetates / chemistry
  • Gas Chromatography-Mass Spectrometry / methods*
  • Limit of Detection
  • Meristem / metabolism
  • Plant Growth Regulators / metabolism*
  • Plant Leaves / metabolism*
  • Plant Roots / metabolism*
  • Reproducibility of Results
  • Trimethylsilyl Compounds / chemistry

Substances

  • Acetamides
  • Fluoroacetates
  • Plant Growth Regulators
  • Trimethylsilyl Compounds
  • N-methyl-N-(trimethylsilyl)trifluoroacetamide