In Vitro Propagation Through Nodal Explants in Helicteres isora L., a Medicinally Important Plant

다국어 초록 (Multilingual Abstract)

Helicteres isora is medicinally important plant effective against asthma, diabetes, hypolipidemia, HIV, besides a good source of diosgenin. Seed dormancy and low rate of natural fruit production make this plant a perfect candidate for developing an in vitro method useful for its clonal propagation and further biotechnological developments. This is the first report on in vitro production of this plant. Nodal explants obtained from aseptically germinated seedlings were cultured on MS medium (Murashige and Skoog 1962) fortified with indole-3-acetic acid (IAA) ($0.57-22.83\;{\mu}M$), indole-3-butyric acid (IBA) ($0.41-16.58\;{\mu}M$), 6-benzylaminopurine (BA) ($0.44-17.75\;{\mu}M$) and kinetin (Kin) ($0.46-13.94\;{\mu}M$) either singly or in combinations of IAA + BA, IAA + Kin and BA + Kin. Combinations of cytokinins (BA and Kin) were most suitable for multiple shoot induction and $13.94\;{\mu}M\;Kin\;+\;13.31\;{\mu}M\;BA$ was optimum (79% frequency) associated with high number of microshoots (7.1 shoots per explant) after 20 days of culture. Maximum shoot elongation and proliferation (10 shoots per explant with 4.8 cm average height) was achieved on MS media containing $2.32\;{\mu}M\;Kin\;+\;2.22\;{\mu}M\;BA\;+\;2.85\;{\mu}M\;IAA$. High rooting frequency (70%) was achieved on MS medium (1/2 basal strength) fortified with $4.14\;{\mu}M$ IBA, while activated charcoal showed inhibitory effects on rooting. Hardening was done with 76% survival rate and these plants were growing without any visual defects and morphologically mimicking the naturally growing plants.