title: Dissecting the role of two cytokinin analogues (INCYDE and PI-55) on in vitro organogenesis, phytohormone accumulation, phytochemical content and antioxidant activity.
abstract: There is a continuous search for new chemical entities to expand the collection of suitable compounds to increase the efficiency of micropropagation protocols. Two cytokinin (CK) analogues, 2-chloro-6-(3-methoxyphenyl)aminopurine (INCYDE) and CK antagonist 6-(2-hydroxy-3-methylbenzylamino)purine (PI-55) were used as a tool to elucidate the auxin-CK crosstalk under in vitro conditions in the medicinally important plant, Eucomis autumnalis subspecies autumnalis. These compounds were tested at 0.01, 0.1 and 10 μM alone as well as in combination with benzyladenine (BA) and naphthaleneacetic acid (NAA). The organogenesis, phytohormone content, phytochemical and antioxidant response in 10 week-old-in vitro regenerated E. autumnalis subspecies autumnalis was evaluated. INCYDE generally favoured shoot regeneration while the effect of PI-55 was more evident in root proliferation. Overall, INCYDE promoted the accumulation of higher concentrations and varieties of endogenous CK relative to the PI-55 treatments. In contrast, higher concentration of indole-3-acetic acid and 2-oxindole-3-acetic acid were generally observed in PI-55-supplemented cultures when compared to plantlets derived from INCYDE. Both CK analogues (individually and in-conjunction with exogenously applied PGRs) significantly influenced the phytochemicals and consequently the antioxidant potential of the in vitro regenerants. These results provided insight on how to alleviate root inhibition, a problem which causes considerable loss of several elite species during micropropagation.
authors.affiliation: Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg Campus, P/Bag X01, Scottsville 3209, South Africa.
authors.forename: Adeyemi O
authors.initials: AO
authors.lastname: Aremu
authors.affiliation: Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg Campus, P/Bag X01, Scottsville 3209, South Africa.
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Stirk
authors.affiliation: Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg Campus, P/Bag X01, Scottsville 3209, South Africa.
authors.forename: Nqobile A
authors.initials: NA
authors.lastname: Masondo
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Plačková
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Novák
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Aleš
authors.initials: A
authors.lastname: Pěnčík
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Zatloukal
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Nisler
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Lukáš
authors.initials: L
authors.lastname: Spíchal
authors.affiliation: Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
authors.forename: Karel
authors.initials: K
authors.lastname: Doležal
authors.affiliation: Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg Campus, P/Bag X01, Scottsville 3209, South Africa.
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Finnie
authors.affiliation: Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg Campus, P/Bag X01, Scottsville 3209, South Africa. Electronic address: rcpgd@ukzn.ac.za.
authors.forename: Johannes
authors.initials: J
authors.lastname: Van Staden
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D003583:Cytokinins / Q000494:pharmacology*; D007210:Indoleacetic Acids / Q000378:metabolism; D019668:Liliaceae / Q000187:drug effects / Q000254:growth & development*; D038081:Organogenesis / Q000187:drug effects*; D064209:Phytochemicals / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development; D046509:Tissue Culture Techniques
chemical_list: C580806:2-chloro-6-(3-methoxyphenyl)aminopurine; D000975:Antioxidants; D003583:Cytokinins; D007210:Indoleacetic Acids; D064209:Phytochemicals; D010937:Plant Growth Regulators; D000225:Adenine
keywords: Antioxidant; Asparagaceae; Auxins; Conservation; Cytokinin homeostasis; Rooting