Metabolite analysis by GC/MS identified significant shifts in metabolite concentrations in
plants treated with BABA and P. nicotianae. Changes in metabolite concentrations were more
pronounced for plants treated with BABA than for plants treated with P. nicotianae, both in
magnitude and in the number of metabolites that changed significantly. Changes in metabolite
concentrations induced by BABA is consistent with previous studies in other plant systems
where pronounced differences were measured within 24 hours after treatment [8]. Consistent
with previous reports, we observe parallel concentration responses for 25 metabolites (of 26
total for which significant concentration change was observed) in plants treated with P. nicotianae
and BABA, which indicates a conserved response mechanism for both elicitors [13].
Primed changes were observed in plants treated with P. nicotianae that were subsequently inoculated
with P. capsici. As the intracellular localization of metabolites cannot be determined
through this analysis, it is difficult to determine their exact biochemical origin within the plant.
However, the observed metabolite changes are consistent with primed production of defense
compounds and to supply the necessary reducing power to generate reactive oxygen species