Endogenous Phytohormones in Spontaneously Regenerated Centaurium erythraea Rafn. Plants Grown In Vitro
Phytohormones are important regulators of numerous developmental and physiological processes in plants. Spontaneous morphogenesis of the common centaury (Centaurium erythraea Rafn.) is possible on nutrition medium without addition of any plant growth regulator depending solely on endogenous phytohormone levels. Thus, this plant species represents a very good model system for the investigation of numerous physiological processes under phytohormonal control in vitro. We analysed the total amount of endogenous cytokinins (CKs) including the contents of their individual groups in shoots and roots of C. erythraea plants grown in vitro. The total amount of endogenous CKs was 1.4 times higher in shoots than in roots. Inactive or weakly active N-glucosides found to predominate in both organs of centaury plants, whereas free bases and O-glucosides represented only a small portion of the total CK pool. Consequently, centaury roots showed higher IAA content as well as IAA/free CK base ratios compared to shoots. Centaury tissues also showed increased levels of “stress hormones”. In contrast to SA, considerably higher levels of ABA were found in centaury shoots than in roots. Our results could serve as a basis for understanding and elucidating spontaneous de novo shoot organogenesis and further plant regeneration of C. erythraea in vitro.
KeywordsCommon centaury Root explants Hormone metabolism Cytokinins Auxins Plant development Stress hormones
Abbreviations for CKs Adopted and Modified According to Kamínek and Others (2000)
cis-zeatin 9-riboside O-glucoside
Dihydrozeatin 9-riboside O-glucoside
N 6-(∆2- isopentenyl)adenine 7-glucoside
N 6-(∆2- isopentenyl)adenine 9-glucoside
N 6-(∆2- isopentenyl)adenine 9-riboside
N 6-(∆2- isopentenyl)adenine 9-riboside-5′-monophosphate
trans-zeatin 9-riboside O-glucoside
This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (Grant No. ON173015) and the Czech Science Foundation (P506/11/0774).
M. Trifunović-Momčilov and M. Petrić contributed to all in vitro experiments. M. Trifunović-Momčilov and V. Motyka contributed in data analyses and manuscript preparation. J. Holík, J. Malbeck and P.I. Dobrev contributed to all experimental work considering endogenous plant hormones analyses. S. Jevremović contributed to all statistical analyses. I.Č. Dragićević contributed to data analyses and obtained result’s interpretation. A. Subotić supervised the whole study and also contributed in preparing the final manuscript.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
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