Effects of activated charcoal, explant size, explant position and sucrose concentration on plant and shoot regeneration of Lilium longiflorum via young stem culture

An efficient system for the in vitro plant and shoot regeneration of Lilium longiflorum was developed and accomplished using transverse thin cell laye rs (tTCL) of young stems. tTCLs were cut transversely along young stems fro m which the shoot-tips had been removed. Sections were measured accurately using a graded grid and were cut in 4 mm x 4 mm x 1 mm cubes, eliminating e pidermal tissue, and were cultured on one-half MS medium containing 8 g l(- 1) agar, different sucrose concentrations (10, 20, 30 or 40 g l(-1)), and w ith or without 1 mg l(-1) activated charcoal (AC). Plants formed on the sur face of tTCLs within 60 days on one-half MS medium containing 8 g l(-1) aga r and 20 g l(-1) sucrose. Sections of 1 mm taken just below the apical area developed buds within 15 days, whereas the sections closer to the base req uired about 45 days. Shoot regeneration was enhanced when sucrose concentra tion was used at 30 or 40 g l(-1) after 60 days of culture. No root formati on occurred. Both shooting and rooting occurred when sucrose was used at 20 g l(-1). The plantlets were transferred to soil and grew well under greenh ouse conditions.