Which of the following statements is not true about somatic embryogenesis ?
- Somatic embryos can develop from microspores
- Somatic embryo is induced usually by an auxin such as 2,4-D
- The pattern of development of a somatic embryo is comparable to that of a zygotic embryo
- A somatic embryo develops from a somatic cell
Answer
(1) Somatic embryos can develop from microspores
Solution
Somatic embryogenesis is the formation of embryos (embryoids) from somatic (vegetative, diploid) cells in tissue culture, without fusion of gametes.
⇒ Statement (4) is true: a somatic embryo develops from a somatic cell.
⇒ Statement (2) is true: it is usually induced by a high concentration of an auxin such as 2,4-D in the medium.
⇒ Statement (3) is true: it passes through globular, heart-shaped and torpedo stages, like a zygotic embryo.
∵ Microspores (pollen grains) are haploid gametophytic cells, not somatic cells; embryos from them are androgenic (haploid) embryos.
∴ Statement (1) is not true.
Answer: (1)