The growth differentiation and organogenesis of tissue occurs only on the addition of one (or) more of these hormones to the medium.
Auxins have the property of cell division, cell elongation, elongation of stem, internodes, tropism.
Apical dominance abscission and rooting
■commonly used auxins are
IAA (Indole 3-Acetic Acid)
IBA (Indole 3-Butyric Acid)
2,4-D (Dichloro Phenoxy Acetic Acid)
NAA (Naphthylene Acitic Acid)
NOA (Naphthoxy Acitic Acid)
The 2,4-D is used for callus induction where as the other auxins are used to root induction.
Cytokinins are adenine derivaties which are mainly concerned with cell division modification of apical dominance, and shoot differentiation in tissue culture.
Cytokinins have been shown to activate RNA synthesis and to stimulate protein and the enzymatic activity in certain tissues
●commonly used Cytokinins are
BAP (6-Benzylamino purine)
BA (Benzy adenine)
2ip (Isopentyl adenine)
Kinetine (6-furfur aminopurine)
Zeatin (4-hydroxy 3 methyl trans 2 butinyl aminopurine)
3. Gibberillins and Abscisic acid
GA3 is most common gibberillin used in tissue culture.
It promotes the growth (f the cell culture at low density.
Enhances callus growth and simulates the elongation of dwarf or stunted plantlets formation from adventive embryos formed in culture.
ABA in culture medium either stimulates or inhibits culture growth depending on species.
It is most commonly used in plant tissue culture to promote distinct developmental pathways such as somatic embryogenesis.