2. Embryogenesis
• Somatic Embryogenesis
“The process of a single cell or a group of cells initiating the
developmental pathway that leads to reproducible regeneration
of non-zygotic embryos capable of germinating to form
complete plants”
• Under natural conditions, this pathway is not normally
followed, but from tissue cultures somatic embryogenesis
occurs most frequently and as an alternative to organogenesis
for regeneration of whole plants.
3. How Somatic Embryos produced?
• In somatic embryogenesis, embryo-like structures, which can
develop into whole plants in a way analogous to zygotic
embryos, are formed from somatic tissues.
• These somatic embryos (SE) can be produced either directly
or indirectly.
• Two ways of somatic embryogenesis:
4. 1. Direct embryogenesis
In direct somatic embryogenesis, the embryo is formed directly from a cell or
small group of cells without the production of an intervening callus.
Direct somatic embryogenesis is generally rare in comparison with indirect
somatic embryogenesis.
2. Indirect embryogenesis
In indirect somatic embryogenesis, callus is first produced from the explant.
Embryos can then be produced from the callus tissue or from a cell suspension
produced from that callus.
7. Importance
In poly embroyonic crops like citrus, zygotic as well as nucellar embryonic plants are
obtained separately.
Embryos of big and heavy fruits like coconut can be taken out of the fruits and pre-
serve in tube in sterile distilled water for about two months and then cultured in
media.
In this process easy international exchange of germplasm is possible.
In many interspecific and intergeneric crosses the hybrid embryos fail to develop to
maturity. In such cases before the embryo gets damaged can be taken out of the ovule
and cultured in artificial media, which gives rise to complete plantlets.
One major path of regeneration
Mass multiplication
Production of artificial seeds
