IN-VITRO CALLUS FORMATION OF RED SANDALWOOD (Pterocarpus santalinus L.) AS AFFECTED BY EXPLANT TYPE AND DIFFERENT LEVELS OF 2,4-D AND BAP

Abstract

Pterocarpus santalinus is a valuable medicinal plant, now included in red listof endangered plants under IUCN guidelines. Distribution of this plant in SriLanka is very limited and the local demand for ayurvedic purposes is stillunreached. As conventional propagation techniques are not satisfactory,possibilities in in-vitro techniques seem to be promising, and callus culture isone aspect that has to be studied. Leaf parts, cotyledon parts, root segments,inter-nodal segments, and nodal segments from in-vitro seedlings were usedas explants. 2,4-D and BAP were used separately in six differentconcentrations (1 mg/l - 6 mg/l) for callus initiation Full strength MS medium(Murashige and Skoog, 1962) was used with 30 g/l of sucrose and 8 g/l agaras the culture medium. Callus formation could be observed in every explant.However, large clumps of creamy white callus were obtained from nodalsegments. Callus formation in root segments was very poor and showedbrown color. In nodal segments, callus formation was started within twoweeks and large clumps of callus were observed while slight swellin~occurring on root segments, leaf parts and in cotyledon parts at the end of 41week. Callus formation was best when the culture medium was supplementedwith 3 mg/l of BAP. Though callus formation could be observed in 2,4-D,amount of callus formed was poor. Present studies revealed that MS mediumsupplemented with 3 mg/l BAP is ideal for callus induction in Pterocarpussantalinus and possibility of using nodal segments as initial explants.