Abstract: This paper deals with a histological observation of adventitious bud formation and somatic embryogenesis of peanut (Arachis hypogaea L.) leaflets. Adventitious buds and embryoids developed from the leaflets of 4-day-old seedlings on MS basai medium supplemented with TDZ 0. 2 mg/L and NAA 0.4 mg/L, and developed into plantlets after they were transferred onto MS medium without any phytohormone. Histological observations showed that both adventitious buds and somatic embryos developed from the surface of the callus. However, adventitious buds originated from cell mass while somatic embryos originated from one single embryogenic cell. The somatic embryos developed directly into plantlets with roots and buds through multicellular proembryo, globular, heart-shaped, torpedo-shaped and cotyledon stages.

Key words: peanut, adventitious bud formation, somatic embryogenesis, histological study