Cytokinin

• Promotes cell division, and influence cell differentiation and aging of leaves.

Action and application

Ø Cell division

Ø Cell enlargement

Ø Morphogenesis

Ø Dormancy

Ø Apical dominance

Ø Mobility: Immobile obstructs the movement of amino acid, phosphate and various other substances

Ø Nucleic acid metabolism: Quick increase in the amount of RNA and decreases DNA

Ø Protein synthesis: Increases DNA

Ø Protein synthesis: Increased rate

Role of Cytokinins

Ø Stimulates cell division.

Ø Stimulates morphogenesis -shoot initiation/bud formation in tissue culture.

Ø Stimulates the growth of lateral buds-release of apical dominance.

Ø Stimulates leaf expansion resulting from cell enlargement.

Ø May enhance stomata opening in some species.