Methyl jasmonate and Echinothrips americanus regulate coumarin accumulation in leaves of Matricaria chamomilla

Matricaria chamomilla synthesize (Z)- and (E)-2-ß-d-glucopyranosyloxy-4-methoxy cinnamic acid (GMCA), the biosynthetic precursors of herniarin. During leaf development the content of (E)-GMCA decreased and no changes were found in the content of other compounds evaluating in the experiments. Methyl jasmonate elicits an increase in (E)-GMCA and herniarin content in young growing leaves as well as mature and senescing leaves 48 h after treatment. In contrast, attack by the thrips, Echinothrips americanus, causes increase not only in GMCAs and herniarin content but also in the amount of coumarin, umbelliferone. The results confirmed that coumarin-like metabolites can be considered as plant defence compounds in biotic and abiotic stress conditions.