Micropropagation of Dipcadi montanum (Dalz.) Baker (Asparagaceae): a rare scapigerous herb.

Abstract

Dipcadi montanum (Dalz.) Baker (Asparagaceae) is a rare scapigerous herb endemic to the Western Ghats, a global biodiversity hotspot running parallel to the western coast of India. This study reports the development of a reproducible protocol for mass propagation of this underutilized geophyte using bulb scale and immature leaf base explants. Miniature bulblets were successfully induced from both types of explants after 4 and 8 weeks of culture on full-strength semisolid MS basal medium fortified with 3% sucrose and varying levels of BAP (4.4-17.7 μM) and TDZ (4.5-18.1 μM). The addition of 2.7 μM NAA further enhanced the rate of microbulb induction. Rooting of the 8-week-old bulblets, obtained from both explants, was achieved with more than 90% efficiency on liquid as well as agar-gelled half-strength MS basal medium fortified with varying levels of IBA (2.46-9.84 μM) and NAA (2.68-10.74 μM), with or without 2.32 μM Kinetin. More than 95% of the rooted plants survived the initial acclimatization process under controlled ex-vitro conditions, and a survival rate of over 80% was recorded after 4 weeks of transfer to greenhouse conditions. After a brief dormancy, the regenerants resumed growth in the postmonsoon season and exhibited morphological resemblance to the donor plant. Comparative cytological analysis between the donor and 15 randomly selected regenerants revealed a stable somatic count of 2n = 20.