Unfolding phenolics biosynthetic plasticity of Artemisia alba Turra through plant tissue culture techniques

Artemisia alba Turra is an essential oil bearing plant, with Euro-Mediterranean and Southeastern European distribution. One of the distinctive characteristics of its essential oil is the variability of its terpenoid profile due to environmental, genetic and other factors. In the present work, tissue culture experiment has provided a model system of in vitro morphogenesis alteration. Auxin and cytokinin treatments were applied alone or in different combinations, leading to the development of directly rooting and root suppressed in vitro plantlets. Direct in vitro rooting was definitely related to obtaining biomass richest in flavonoid compounds (irrespectively of the PGR combination leading to obtaining this morphotype). The directly rooting morphotype was also distinguished by the highest flavones/flavonoles ratio as compared with the in situ and the rest of the in vitro samples. Underground parts of in vitro samples were shown to be significantly richer in caffeoylquinic acids as compared with aerial parts. An elevation of DCQA/CQA ratios in PGR treated plants as compared with the non-treated control could be estimated as an indication of stimulation of the esterification process with the purpose of coping with the stress of the impairment of the physiological state of normal shoot-to-root tissue formation. It was shown that in vitro morphogenesis moderation could be applied as a simple and reproducible protocol to alter polyphenolics production in tissue cultures of this plant species.