In Vitro Propagation and Phytochemical Investigation of Ledebouria graminifolia, an Important Medicinal Bulb in Southern Africa

Abstract

ABSTRACT An in vitro propagation method was investigated for Ledebouria graminifolia (Hyacinthaceae), an important medicinal plant from which the bulb is used in Botswana and Southern Africa. Twin-scale and scale leaf explants were cultured on basic Murashige and Skoog (MS) medium supplemented with different concentrations of benzyladenine (BA) and napthaleneacetic acid (NAA). MS medium containing 2 mg/liter BA alone stimulated axillary bud growth in twin scale explants, but did not induce organogenesis in the scale leaf explants. A medium with 2 mg/liter BA + 2 mg/liter NAA induced shoot and root development and promoted callus formation. The highest shoot regeneration rate (average of 3 shoots per explant) was achieved in MS medium supplemented with 2 mg/liter BA + 0.2 mg/liter NAA. The adaxial side of the scale leaves showed more shoot regeneration than the abaxial side. Regenerated shoots developed roots within one week after transfer to a hormone-free, root-inducing MS medium. The plantlets were successfully acclimatized in the soil with a 90 percent survival rate. Phyto-chemical investigations of the in vitro regenerated L. graminifolia bulbs revealed the presence of 11 homoisoflavonoids, and two xanthones that had previously been isolated from wild bulbs of L. graminifolia.