Molecular insights of somatic embryogenesis in coconut.

Cocos nucifera L.(Coconut) is a multipurpose plantation crop which is always in high demand as utility have increased for its products. However, old/senile orchards along with pest and diseases resulted in decreased production and productivity thereby compelling to take up replantation. Micropropagation through Somatic Embryogenesis (SE) is the most promising way for mass propagation in coconut. Although mass production is possible, disadvantages like varying responses of genotypes, culture conditions, somaclonal variation, etc., restrict it from being exploited commercially. On this account, understanding the molecular process involved in somatic embryogenesis is essential to prevail over the drawbacks. Several developmental stages involved in SE, include stimulation of cell proliferation, acquisition of cell competence, generation of somatic embryos and germination of embryos into plantlets. To regulate these phenomena, specific signalling pathways are activated and gene expression patterns are highly regulated. All possible gene regulatory systems, transcription factors and epigenetic modifications involved in cell cycle, dedifferentiation, totipotency, embryo induction and establishment, during SE of coconut are discussed.