Environmental design considerations for somatic embryogenesis

In addition to the biomolecular, physiological, and biochemical aspects of somatic embryogenesis, careful design of environmental conditions is necessary to ensure the successful induction and development of somatic embryos for different plant species. A dissolved oxygen concentration, for instance, below 10% generally inhibits the differentiation of somatic embryos, while the same is promoted at 40, 80, or 100%, depending on the plant species. Certain plant species also exhibit inhibition of somatic embryo differentiation at high dissolved oxygen concentration, such as at 80%. Cell density influences somatic embryogenesis by changing the concentrations of conditioning factors released by plant cells and embryos into the culture medium. High initial cell density, in general, results in inhibition of somatic embryo differentiation on account of inhibitory compounds released by cells into the culture medium. Partial medium replacement has been employed to rectify this situation. In terms of the general influence of light, red light promotes and blue light inhibits the induction of somatic embryos. Blue light, however, generally promotes the development of somatic embryos.