Organogenic Differentiation
For the regeneration of whole plant from a cell or from a callus mass, Cytodifferentiation alone is not enough and there should be differentiation leading to organogenesis (organ formation = formation of stem, roots, flowers, etc.). This may occur either through shoot bud differentiation or through somatic embryogenesis. In the former, shoot buds (monopolar structures) are formed while in the latter, somatic ambryos (bipolar structures) are formed, both leading to regeneration of whole plants.