Direct induction of somatic embryogenesis from immature zygotic embryo of cashewnut ( Anacardium occidentale L.)

Abstract

Direct somatic embryogenesis was induced in precociously germinated immature zygotic embryos (IZEs) of cashewnut ( Anacardium occidentale L.). The IZEs were cultured on semisolid Murashige and Skoog (MS) basal medium with 0.5% activated charcoal and incubated in dark. After 4–5 weeks, somatic embryos were induced directly from the radical tip of IZEs on medium with 2,4-dichlorophenoxyacetic acid (2,4-D) (5 μM)+ BAP (5 μM)+ gibberellic acid (GA 3) (3 μM) with 10% frequency of embryogenic response, which was 9% when 2,4-D (5 μM) was used alone or with Kinetin (Kin) (5 μM). The somatic embryos were transferred to medium with abscissic acid (ABA) (20 μM) and maltose (3%) for further maturation and, studies are being carried out for conversion of somatic embryos into plantlets. A histological study of somatic embryo development was carried out where it was seen that the somatic embryos arose from the outermost cell layer of radical tip.