Abstract

In vitro cultures of the medicinal plant Maesa lanceolata were established to enable the cultivation of plant material for the production of protoplasts. Callus cultures were initiated using leaves collected from shoot cultures and the root tips from hairy root cultures obtained upon Agrobacterium rhizogenes transformation. For the isolation of protoplasts, the different explant material of M. lanceolata was exposed to an enzyme mixture consisting of 1.5% cellulase, 0.5% macerozyme R-10 and 0.5 M mannitol. About 6 x 10⁶ protoplasts g^-1 fresh weight were obtained from leaf material and 5 x 10⁵ protoplasts g^-1 fresh weight from callus. To obtain high amounts of hairy root protoplasts, the cultures were pre-treated with the auxin indole-3-butyric acid (IBA) that stimulated the formation of novel root tips. Using the dissected root tips as starting material, 8 x 10⁵ protoplasts g^-1 fresh weight were obtained per preparation. The protoplast isolation method will enable further studies on the transformation and fusion of protoplasts from M. lanceolata.

Key words: Maesa lanceolata, in vitro conservation, tissue culture, protoplast isolation.

Abbreviation

2,4-D, 2,4-Dichlorophenoxyacetic acid; BA, N₆-benzylaminopurine;IAA, indole-3-acetic acid; IBA, indole-3-butyric acid; NAA, α-naphthalene acetic acid; MS, Murashige and Skoog.