XVI International Botanical Congess

Mass multiplication of fast-growing, multipurpose trees has proved to be a promising tool for rapid afforestation, conservation and reclamation. The present communication reports clonal propagation of Casuarina equisetifolia Linn, of the Casuarinaceae and Leucaena leucocephala (Lam.) De Wit of the Fabaceae, using explants derived from in vivo grown elite trees. Shoot apices (1-10 mm long) of Casuarina formed multiple shoot buds and shoots on NB+2-2.5 mg/l BA+0.1 mg/l NAA within 90 days of initial culture. However, in Leucaena regenerationof shoots was achieved from 2-3 mm long shoot tips excised from young branches of five-year-old trees. The optimum medium for multiple shoot differentiation was MS+3 mg/l BA+0.05 mg/l NAA. The shoots were successfully rooted on MS medium containing 1 mg/l IAA within 15 days. The use of polyvinylpyrrolidone (PVP) at 250-500 mg/l was most effective in checking browning of cultures as well as in promoting differentiation of multiple shoots in both the tree species.