Histocytology of somatic embryogenesis in peanut( Arachis hypogaea L.)

Somatic embryos were induced from mature embryo axes cultured on basal MS medium supplemented with 40 mg/L 2,4D.When decreasing the level of 2,4D,yellow embryogenic callus were induced from tissue of somatic embryos cultured for 2～3 times,and somatic embryos at different stages appeared.Somatic embryogenesis directly from epidermical cells or subepidermical cells was similar to that of the zygotic embryo.Embryoid were originated from a single embryogenic cell,which had bigger nuclei,thick cytoplasm clear nucleoli and denser order.The embryogenic cell first divided into twocell proembryo,then three or fourcell proembryo.Three or fourcell proembryo developed into multiple cell proembryo,then developed into embryo.