Somatic embryogenesis and plants from immature zygotic embryos of the species Musa acuminata and Musa balbisiana.

Callus was obtained from immature zygotic embryos of semminiferous species (diploids) of Musa sp. using a medium derived from that of Murashige and Skoog. Picloram (7.5 μM) was added and the medium was solidified with gelrite (2 gl(-1)). Differentiation of the first somatic embryos occurred after transfer of the callus in the presence of 7.5 μM picloram or 5.3 μM NAA. Somatic embryos germinated on the medium supplemented with 5.3 μM NAA. Serial sections of zygotic and somatic embryos showed perfect homology in their structure (epidermis, cotyledonary slit, shoot apex and 3 root primordia). Embryonic callus was characterised by a large quantity of protein storage in the cytoplasm.