Assessment of Invitro Propagation and Conservation of Swertia Chirayata

Abstract

A protocol for in vitro propagation and conservation was developed for Swertia chirayita, an endangered medicinal plant. The sterilized explants (leaves) cultured on MS medium supplemented with 0.1 mg/l NAA and 3.0 mg/l BA gave best results for in vitro callus induction. Shoot regeneration was obtained from the callus on the same medium. The in vitro shoots cultured on MS medium supplemented with 2.5 mg/l BA and 0.1 mg/l Kinetin gave best results for in vitro shoot multiplication. The MS medium supplemented with 0.1 mg/l NAA and 3.0 mg/l BA medium was found to be the best for direct shoot regeneration from in vitro leaves. 80.30% root induction from in vitro grown shoots was obtained on half strength MS medium supplemented with 400 mg/l activated charcoal and 0.1 mg/l NAA. In vitro conservation was carried out by using two different approaches namely slow growth by changing media composition (sucrose and abscisic acid), at low temperature and cryopreservation following vitrification.With increase in concentration of sucrose and ABA decrease in growth of in vitro shoots was observed. No shoot multiplication with average leaf size of 0.35 cm and shoot length 0.67 cm was observed on half MS containing 90 g/l sucrose. Similarily, in case of media containing half strength MS salts and 3.0 mg/l ABA showed no shoot multiplication,0.83 cm average leaf size and 0.83 cm shoot length. At low temperature the in vitro shoots incubated at 4o C, showed 100% retrieval, with 1.00 cm average number of shoots, 0.86 cm shoot length and 0.34 cm leaf size. In vitro shoots incubated at 10o C, showed 100% retrieval, with 1.00 cm average number of shoots, 0.76 cm shoot length and 0.23 cm leaf size. During studies the vitrified shoot gave retrieval of 42.33% when precooled at 4o C while only 22.37% vitrified shoots were retrieved from those precooled at 10o C.