Question

List 4 distinct stages of somatic embryogenesis? Describe them.

Answer 1

Somatic enbryogenesis is a process in which embryo is obtained from a single somatic cell by artificial means of process. These embryos are made up of cells of ordinary plant tissues ( normally not involved in the development of embryos).

Stages of somatic embryogenesis:

1. initial callus induction (induction)

2. middle callus growth (development)

3. Late embryogenic callus induction phase (maturation)

4. Fully grown somatic embryo

INDUCTION : Auxin is very necessary to induce embryogenesis. Requirement of auxin for embryogenesis depends upon the nature of explants used with the relative concentrarion of auxins.

DEVELOPMENT: After initiation of cell division and proliferation, embryogenic cells are released into auxin free medium. These cells forms the cluster of cells of cytoplasm and are known as Proembryonic mass of cells (PEM)

MATURATION : somatic embryos are incomplete in development therefore they have poor response in germination and conversion into plant. somatic embryos do not increase in size during maturation like other mebryos due to lack of specific reserve food and proteins.