IN VITRO CALLUS PRODUCTION OF Pterocarpus santalinus L. (RED SANDAL) THROUGH NODAL CUTTINGS, SHOOT TIPS AND LEAF DISCS

Abstract

Pterocarpus santalinus L. is highly demanded rare medicinal plant, which isused in Ayurveda and not naturally occurred in Sri Lanka. It is used as homeremedies since ancient times. There are records on few cultivated plants indry areas especially in southern part of the country. Normally plants arepropagated by fresh seeds, but it requires special treatment for seedgermination. Not only that, the percentage germination is also very low. Withthe aim of developing a protocol for mass propagation through in vitrotechniques, nodal cuttings, shoot tips and leaf discs from tender leaves atrejuvenation period were used as explants. Explants were cultured on basicMurashige & Skoog (MS) medium supplemented with Kinetin, NAA, BAP,IBA, & Calcium panthothenate at a range of concentrations and on B,medium supplemented with BAP and Kinetin at different concentrations.While 3% (WN) sucrose was added (pH = 5.7) to MS medium, 2% (W/V)sucrose was added to B, medium (pH = 5.5). Agar at 0.8% was added to bothmedia for solidification. Cultures were incubated at 25±1° C temperature andkept under different light intensities. Callus initiation was observed after 14-21 days of incubation in 16 hr light. Callus was initiated and continuedgrowth only in 16hr light condition in MS medium. In B, medium callus wasinitiated but not continued the growth any further. Best explant source forcallus production was nodal cuttings. Embryogenic callus was obtained fromleaf discs in MS medium, mainly from the cultures incubated in dark. Smallamount of embryogenic callus was initiated under light conditions in thesame medium. Embryogenic callus could be grown in cell cultures andthereby can produce large number of somatic embryos which may be lead tomass production of plants. The amount of callus production and the nature ofcallus depend on the explant type, growth regulators used and incubationconditions.Direct shoot elongation occurred at low percentage (10%) in MSmedium supplemented with O.2mg/L Kinetin, O.lmg/L NAA, 0.5 mg/L BAP,0.3mg /L IBA and O.lmg/L and Calcium panthothenate. It was even lesser«5%) in all the other media tested.