RAPID IN-VITRO PROPAGATION OF EAST-INDIAN ROSEWOOD (DALBERGIA-LATIFOLIA ROXB.) THROUGH HIGH-FREQUENCY SHOOT PROLIFERATION FROM COTYLEDONARYNODES

An efficient protocol is described for large scale in vitro propagatio n of east Indian rosewood (Dalbergia latifolia Roxb.) using cotyledona ry nodes derived from axenic seedlings. Of the four different cytokini ns tested, BA was most effective in inducing multiple shoot buds in th e explants. High frequency shoot proliferation (93%) coupled with maxi mum number of shoot formation (10-12 shoots/explant) was recorded on M urashige and Skoog's medium supplemented with 2.0 mg/l BA. The frequen cy of shoot proliferation declined at higher levels of cytokinins. Sho ot culture was multiplied by subculturing the original cotyledonary no de on a fresh shoot multiplication medium each time after excising the newly formed shoots. Shoots obtained from each passage were multiplie d further as nodal explants and each node produced 3-4 shoots. In two months from a single cotyledonary node, about 90 shoots were obtained. Rooting was induced in 72% of the regenerated shoots on half-strength MS containing IAA, IBA and IPA each at 1.0 mg/l. Rooted plantlets wer e hardened off and eventually established in soil.