Starch dynamics as an important factor in early stages of somatic embryogenesis – a review

Somatic embryogenesis is an artificially induced process that results in the formation of an embryo without the fusion of gametes. Despite its significant potential for plant propagation and conservation of plant genetic resources, many unknowns remain regarding the specific mechanisms and the complexity of genetic, biochemical, and cellular regulations involved. The comparative data on induction of embryogenic tissue and the maturation of somatic embryos, along with additional results, suggest that complex carbohydrate dynamics are among the key factors involved. This review summarizes recent findings focused on early stages of SE, including induction, proliferation, comparison of embryogenic cell lines with contrasting embryogenic capacity, and loss of embryogenic capacity after prolonged cultivation obtained through various methods, including metabolomics, proteomics, transcriptomics, and cytological techniques/histochemical visualization, which highlight the regulation of the energy source starch. This encompasses its synthesis and remobilization, driven by related enzymatic machinery, as crucial for determining embryogenic capacity and prognosis in embryo maturation and germination in many economically important plant species. We also outline potential future directions, critical questions to address, and anticipated advancements in the topic, including the development of new research methodologies.