Airborne Methyl Jasmonate is Metabolized to Jasmonic Acid and 12‐Hydroxyjasmonic Acid, and Induces Jasmonate Biosynthesis in Marchantia polymorpha

Abstract Methyl jasmonate (MeJA) is a volatile jasmonate compound commonly used to induce defense responses in spermatophytes. This study reports that airborne MeJA‐d 3 , deuterated MeJA, increases the levels of (dinor‐)12‐oxo‐phytodienoic acids [(dn‐)OPDAs] and jasmonic acid (JA) as well as JA‐d 3 and 12‐hydroxyjasmonic acid‐d 2 (12‐OH‐JA‐d 2 ), MeJA‐d 3 metabolites, in the model bryophyte Marchantia polymorpha . Enhancement of JA biosynthesis was substantiated by the expression of JA biosynthetic genes induced by airborne MeJA. Additionally, each of enantiomers, (+)‐MeJA and (−)‐MeJA, was observed to induce the accumulation of JA and (dn‐)OPDAs in M. polymorpha . This study demonstrates that airborne MeJA is metabolized to JA and 12‐OH‐JA, and induces JA biosynthesis in M. polymorpha . Moreover, the transient increase in endogenous JA level after airborne MeJA treatment provides concrete evidence that M. polymorpha biosynthesizes JA.