During the bamboo embryogenesis, the embryoids initiate and develop from somatic cells.
Compared with organogenesis, somatic embryogenesis is characterized by the formation of
a bipolar structure, which will develop into plumule and radicle (Fig.2e-g). Histological
analysis reveals that embryogenic cells are small in size, isodiametric with dense cytoplasm,
generally locate along the periphery of calli, distribute in clusters, and intersperse with large
parenchymal cells. Somatic embryos gradually developed from the granular onsite to heartshaped,
torpedo-shaped, and final cotyledons (Zhang et al., 2010).