Morphological and chemical characterization of Arnica montana L. under different cultivation models

Abstract

Arnica (Arnica montana L) is a perennial mountain plant whose flower heads are mainly used for topical treatment of bruises and sprains in phytopharmaceutical preparations such as ointments, creams and gels. In this study, different models of arnica cultivation have been tested in three-year field trial arranged in 2 x 3 x 2 factorial design. Planting date (spring and autumn), fertilizater type (manure, NPK and control) and mode of reproduction (generative and clonal) were induced factors on the trial. The variation of the rosette diameter, flowering stem count and height, flower heads count and diameter, together with flower heads yield and chemical properties were investigated as morphological parameters. Spring planting of clonally propagated plants was showed to be the least successful model due to the low percent of rooted plants and weak shoot development. Other models yielded from 59.8 to 143.6 kg ha(-1) and 116.3 to 258.7 kg ha(-1) flower heads (dw) in the second and third year, respectively. Total sesquiterpene lactones content in flower heads of all tested variants was above the minimum of pharmacopeia quality regulation and ranged from 4.6 to 13.9 mg g(-1) depending on factor levels, while the amounts of two dominant flavonoid compounds quercetin-3-O-glucoside and kaempferol-3-O-glucoside ranged from 7.8 to 13.9 mg g(-1) and from 2.1 to 4.7 mg g(-1), respectively. All induced factors in the field trial significantly influenced variation in both morphological and chemical parameters, where fertilized variants from autumn planting have shown to be superior in flower heads yield with satisfying levels of the secondary metabolites content. Factorial analysis distinguished that half of morphological parameters positively correlated with flower heads yield. First three ranks of sequential classification of cultivation models with desirable properties were captured by variants planted in autumn, while the last rated variants were those from clonal propagation planted in spring. This attempt of arnica domestication in agroecological conditions of western Serbia has proven to be successful in ensuring high quality raw material, providing at the same time answers to the questions that have not been reviewed so far.