Artemisia
From the 868 metabolites that were detected in the Artemisia shoot
samples, 451 (52%) metabolites were significantly different between at
least two rhizobacteria treatments. In the PCA, the first two PCs
explained 80% of the total variance (Figure 2b1 ). The first
principal component explained more than 64% of the total variance and
corresponds to metabolites that were either reduced or accumulated
during the most effective partnership of the host with Pbg(Figure 2b1 and 2b2 cluster 1 ( reduced
metabolites) and cluster 2 (induced metabolites)). Flavanones,
flavonol glycosides, coumarins, benzoic acid derivatives, acylated
polyamine, catechols, fatty acyl glycosides of mono- and disaccharides,
dipeptide and terpene glycosides showed significant reductions uponPbg inoculation. Various other metabolites belonging to the
compound classes hydroxycinnamoyl quinic acids and derivatives, organic
acids, mono and diterpenoids, and iridoids showed a significant increase
after root inoculation with Pbg . Treatment of Artemisia withPbg resulted in significant reduction in artemisinic acid while
the relative levels of both dihydroartemisinin and artemisinic alcohol
significantly increased. PC2 explained 16% of the total variance and
corresponded to induced metabolites (cluster 3 ) in response toPf SS101 inoculation. Putative metabolite identification revealed
that the amino acid arginine, fatty acyl glycoside blumenol glycoside
and phenylpropanoid glycoside derivatives were induced in a PfSS101-specific manner.