Ex-Situ Conservation of An Endangered Medicinal Plant Andrographis Paniculata By Plant Tissue Culture

An effective and rapid in vitro regeneration protocol of Kalmegh (Andrographis paniculata) was established by investigating the factors like combinations of plant growth regulators and explant types (stem, leaf and midrib). To find out the effective medium for callus induction and shoot regeneration, different explants of A. paniculata were cultured on MS media enriched with several concentrations of 6-benzylaminopurine (BA), α-naphthalene acetic acid (NAA) and 2, 4-dichlorophenoxy acetic acid (2,4-D). Stem explant was noticed more responsive than leaf and midrib explant both in callus initiation and shoot regeneration. The ranges of callus initiation from stem, leaf and midrib explants were 26.67 - 100%, 20 - 93.33% and 13.33 - 73.33%, respectively. The calli obtained from midrib explants were not used in shoot initiation because of its poor size. The stem explant exhibited the maximum 73.33% shoot regeneration frequency in a comparison with leaf explants (60%). The maximum callus induction (100%) and shoot regeneration (73.33%) from stem explants were noticed in MS medium strengthened with 0.5 mg/L NAA and 2.0 mg/L BA and half strength MS media complemented with 0.1 mg/L NAA and 3.0 mg/L BA respectively. The highest shoot regeneration from the stem explant may be due to presence of more active parenchymatous cells than that of leaf explant. Half MS medium fortified with 2.0 mg/L IBA considered as best root initiation medium as it resulted in maximum rooting (93.33%). After acclimatization, the plants were transferred to field and found identical to the mother plant.