Direct somatic embryogenesis and plant regeneration from immature embryos of hybrid sunflower (Helianthus annuus L.) on a high sucrose-containing medium.

Somatic embryos of sunflower (Helianthus annuus) were obtained by placing immature zygotic embryos on a high sucrose (12%) containing medium. The somatic embryos were first observed 6 days after culture and a callus intermediate was not formed. Histological examination revealed the classical stages of embryo development. The somatic embryos proliferated directly from the surface of the zygotic embryos and germinated after placement on a low sucrose medium. Seeds have been obtained from regenerated plants.