Effects of root colonization by symbiotic arbuscular mycorrhizal fungi on the yield of pharmacologically active compounds in Angelica archangelica L.

The major effects of arbuscular mycorrhizal fungi (AMF) colonization on plant growth, monoterpenoids and coumarins were determined in two genotypes of angelica (Angelica archangelica L., Apiaceae). Genetically uniform experimental plants were used, which was achieved by in vitro propagation of two genotypes (individual plants). The effects of Glomus mosseae (Funneliformis mosseae, BEG 12), Glomus intraradices (Rhizophagus intraradices, BB-E) and the AMF mixture Symbivit (R) were tested against a negative (without AMF and without additional phosphorus) and a positive (KH2PO4 without AMF) control in five plants per treatment. All in all 50 plants were investigated. Fifteen monoterpenoid and seven coumarin compounds were quantitatively determined in the rhizome and coarse root fractions by means of GC/MS using an internal standard. The sum of the monoterpenoids and coumarins was calculated. Concentrations of compounds rather slightly decreased upon inoculation with AMF when compared to the control. In contrast, biomass increased showing the highest amounts for plants treated with G. mosseae. These results finally caused a marked increase in yield for G. mosseae treated plants compared to the control. Phosphorus treatment led to the lowest yield with significant results for coumarins and in particular for osthole compared to G. mosseae treatment. This is also evidence of an independent effect from an increased phosphorus uptake due to root colonization by AMF. In summary, the results showed a marked increase in yield of all investigated compounds through treatment with G. mosseae compared to the control group, even if the level of significance was just barely missed presumably on account of the small sample size.