Clonal propagation of Crataegus monogyna Jacq. (Lindm.)

Hawthorn (Crataegus spp.) is an important medicinal plant which exhibits clinically proven improvements of cardiac functions [1]. Five hawthorn species plus hybrids, including Crataegus monogyna Jacq. (Lindm.), are allowed for the drug „Crataegi folium cum flore“ (Hawthorn leaf and flower), and a minimum content of 1.5% flavonoids is claimed [2]. Highly fluctuating quality due to wild collection of the plant material from different species and genotypes resulted in increasing interest in controlled field culture of defined clones [3]. In vitro-propagation could provide an opportunity for the production of genetically homogenous seedlings. Winter buds were collected from a mature C. monogyna tree in spring and were surface-sterilized prior to inoculation on MS medium [4] with 10µM zeatin. Nodal explants were excised from regenerated shoots and inoculated on MS media supplemented with factorial combinations of the plant growth regulators 6-benzylaminopurine and indole-3-butyric acid. Micropropagated shoots were subsequently potted into soil after dipping the base in Seradix® B3 rooting powder, acclimatized in a mist chamber, and then transferred to a test plot after further hardening in the greenhouse. The flavonoid patterns of single plants of an 8 years old clone were analyzed by HPLC. The contents of the major flavonoids were uniform within the trees. The flavonoid pattern of the in vitro-multiplied individuals showed a good concurrence with the mother plant, too. Our results indicate that micropropagation of Crataegus monogyna through nodal culture can be a potential alternative to the slow conventional propagation through cuttings. In respect of flavonoid content, genetically homogeneous plantlets for further field culture can be produced, thus making possible a standardization of the final herbal medicinal product at an early stage of the production chain.

References: [1] ESCOP Monographs (2003). Thieme. Stuttgart. [2] Pharmacopoeia Europaea, 5^th edn. (2005). [3] Sonnenschein, M., Plescher, A. (2005) Pharm. Unserer Zeit 34: 42–47. [4] Murashige, T., Skoog, F. (1962) Physiol. Plant. 15: 473–497.