In vitro Plant Regeneration through Somatic Embryogenesis in Medicinally Important leaf explants of Coleus forskohlii Briq.

Abstract

High-frequency somatic embryogenesis and complete plant regeneration from leaf explants of Coleus forskohlii Briq had been established. The influence of plant growth regulators (PGRs) on the frequency of somatic embryogenesis and plant regeneration were studied. Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) alone or both with 6-benzylaminopurine (BAP), were superior for somatic embryogenesis. Primarily, embryogenic callus was initiated from leaf explants of young plant on MS medium supplemented with 2,4-D (1.0mgl -1 ), 3% sucrose and 0.9% agar in three weeks. Embryogenic callus transferred on 2,4-D and BAP-supplemented medium favored induction of embryos in advance as compared to that on 2,4-D alone supplemented medium. The highest frequency (80 %) of direct somatic embryogenesis was obtained in the combination of BAP (1.0 mg/l) and 2,4-D (0.5 mg/l). Eighty percent of the embryos underwent maturation and conversion to plantlets upon transfer to half-strength MS medium having α-naphthaleneacetic acid (NAA), with BAP. Embryo-derived plantlets were transferred onto specially made plastic cup containing soilrite followed by their transfer to the garden soil. Survival rate of the plantlets under ex vitro condition was 80%.