Somatic embryogenesis and plant regeneration from immature embryo cultute of Pharbitis nil

Abstract

We have developed an efficient system for somatic embryogenesis and plant regeneration from immature embryo cultures of Pharbitis nil. The size of immature embryos and the concentrations of naphthaleneacetic acid (NAA) and sucrose used were found to be critical. Embryos 1–3 mm long and a combination of 3 mg/l NAA and 6% sucrose resulted in somatic embryogenesis with high frequency (80%). Somatic embryoid maturation and germination could be achieved by culturing the embryoids on Murashige and Skoog (MS) medium containing 2 mg/l benzylaminopurine (BA), 0.2 mg/l indole-3-acetic acid (IAA) and 3% sucrose. Plants regenerated from somatic embryos appeared morphologically normal and grew to maturity under growth chamber conditions. Histological observations showed that the embryos were derived from both peripheral (epidermal and subepidermal) and internal meristematic cells (adjacent to the xylem of the vascular bundle) of the hypocotyl axis.