2016, Vol. 4, Issue 5, Part C

author(s)
Papori Phukan Borpuzari and Mina Borthakur

abstract
Plant regeneration was achieved from indirect somatic embryogenesis in Plumbago rosea. Embryonic callus induced from matured leaf, petiole and inter node explants grown on Murashige & Skoog (MS) medium supplemented with 2,4-dichloro-phenoxy acetic acid (2,4-D, 4.0 mgL-1) alone or in combinations with indole-3-acetic acid (IAA, 0.5 mgL-1), yeast extract (YE, 100.0 mgL-1), coconut water (CW, 10% v/v) and casein hydrolysate (CH, 100 mgL-1). Maximum callus induction was obtained from internode explants cultured on media containing 2,4-D (4.0 mgL-1), IAA (0.5 mgL-1), CW (100.0 mgL-1) and YE (100.0 mgL-1). Frequency of callus development, their nature and texture also differed based on their sources and effect of growth regulator concentrations. Frequency of globular embryo formation and a varied germination was recorded from explants source and nutritional media fortified with lower level of 2,4-D. Maximum maturation of globular embryo was recorded in 2,4-D (2.0 mgL-1), IAA (0.5 mgL-1) and YE (100.0 mgL-1). Subsequently germinated embryo developed into normal plants after being transferred to half strength of MS liquid medium. Our whole findings indicated that internode is the best tissue source for optimal somatic embryogenesis of P. rosea. Direct formation of somatic embryos also induced young in vitro grown plantlets (9 days old) and root segment of 5.0 cm when cultured in the medium containing kinetin (Kn, 2.0 mgL-1) and 2-naphthoxyacetic acid (NAA, 0.5 mgL-1) respectively. Hence, attempts to induce direct somatic embryogenesis have been achieved up to embryo regeneration and maturation.