In vitro propagation via organogenesis and synthetic seeds of Urginea altissima (L.f.) Baker: a threatened medicinal plant.

Abstract

Efficient in vitro propagation systems via organogenesis and synthetic seeds were developed for the first time for conservation and commercial propagation from leaf or longitudinal thin cell layer (lTCL) leaf or shoot-tip explants of Urginea altissima. Various plant growth regulators and phloroglucinol were used in semi-solid and liquid Murashige and Skoog (MS) medium to establish multiplication of shoots and roots for in vitro regeneration. Of the various treatments, the highest number of shoots (17.4 per lTCL leaf explant) was obtained on liquid MS medium supplemented with 10µM meta-Topolin (mT) and 2µM benzyladenine followed by transferal to semi-solid MS media. The shoot tips were encapsulated with liquid MS medium plus 3% (w/v) sodium alginate and 100mM calcium chloride. Adventitious shoot regeneration (91.0%; 12.6 shoots per synthetic seed) of synthetic seeds was achieved on semi-solid MS medium supplemented with 10µM mT and 2µM naphthaleneacetic acid (NAA) after 15days of storage in darkness at 25±2°C. Regenerated shoots rooted (9.8 roots per shoot; 6.5cm long) efficiently when transferred to 5µM indole-3-butyric acid and 2.5µM NAA. All the plantlets were successfully acclimatized (100%) in a vermiculite:soil (1:1 v/v) mixture in the greenhouse.