Influence of Incubation Period on Callus Tissues for Plant Regeneration in Ophiorrhiza pectinata Arn. Through Somatic Embryogenesis

Abstract

Ophiorrhiza pectinata Arn. is an important medicinal plant reported to contain camptothecin which is used for the treatment of different types of cancers. The present study describes an efficient plant regeneration system through somatic embryogenesis. Embryogenic callus tissues raised from aseptic leaf explants were used for inducing somatic embryos under incubation of callus tissues at varying periods from 10 to 60 days. It was noticed that callus tissues incubated between 30 and 50 days in 0.5 mg l−1 2,4-dichlorophenoxy acetic acid were responded positively in half-strength Murashige and Skoog liquid media supplemented with 3 mg l−1 indole-3-acetic acid and started differentiation of globular structures in 15–20 days. Maximum differentiation of embryos was obtained in callus tissues incubated for 40 days. Clumps of embryos at different stages got differentiated into plantlets in MS media supplemented with 6-benzyl aminopurine (0.2 mg l−1) and indole-3-acetic acid (0.1 mg l−1) and produced an average of 47.92 ± 5.33 plants from 1.0 to 1.5 g callus tissues. The regenerated plantlets were successfully deflasked, hardened and established in paper cups filled with coarse sand and recorded more than 90% establishment under shade net house (50% shade) condition with adequate watering. The method of plant regeneration system developed would be useful for raising large number of plants and production of bioactive compounds.