Direct somatic embryogenesis from zygotic embryos of a timber-yielding leguminous tree, Hardwickia binata Roxb.

We report here direct somatic embryogenesis from semi-mature zygotic embryos (60-75 days after anthesis) of a timber-yielding leguminous tree, Hardwickia binata Roxb,, commonly known as Anjan. High frequency direct somatic embryogenesis was achieved on Murashige and Skoog's (MS) medium supplemented with 2.26 muM 2,4-dichlorophenoxyacetic acid (2,4-D). Somatic embryos proliferated rapidly in subsequent cultures, Various developmental stages were observed during the maturation of somatic embryos, including globular, heart-shaped, torpedo and cotyledonary stages. Maturation of somatic embryos was achieved by transferring isolated somatic embryos to Ms medium containing 0.26 muM alpha -naphthaleneacetic acid (NAA) and 2.22 muM 6-benzylaminopurine (BAP) or 1.89 muM abscisic acid (ABA). In long-term cultures, secondary somatic embryos developed from isolated torpedo-shaped and cotyledonary embryos. Bipolarity of the somatic embryos was confirmed by histological studies.