·       

2.  In vitro somatic embryogenesis

In vitro somatic embryogenesis (SE) was first demonstrated in 1958 by Reinert and Steward. There are two ways by which SE could be obtained - i) Indirect SE, where first the callusing is induced from the explant by rapid cell division and later the callus give rise to SE (Figure 8.2), and ii) Direct SE, where the somatic embryos are developed directly from the explant without an intermediate callus phase (Figure 8.3).

Figure 8.2: Somatic embryogenesis via callusing showing the development of globular(G), heart (H),                       torpedo (T) and dicot embryos (D) (arrow marked).

Figure 8.3: Direct somatic embryogenesis from cotyledon explant showing embryos at various                      stages of development