In vitro propagation of the alkaloid-producing rare African liana, Triphyophyllum peltatum (Dioncophyllaceae)

Abstract.

Triphyophyllum peltatum (Dioncophyllaceae), a West African liana containing pharmaceutically promising naphthylisoquinoline alkaloids, has successfully been raised in vitro. A clonal propagation protocol has been developed that uses axenically grown juvenile plants as starting material. The addition of naphthaleneacetic acid (NAA) and thidiazuron, both at concentrations of 0.01 mg/l, to the culture medium was found to be an acceptable compromise between the number of induced shoots and excessive callusing. Shoots rooted best in vitro in sterile water, and plants that had already developed roots showed better growth in the greenhouse after weaning. If the weaning process was done slowly and under conditions of high relative humidity, the plants did not require an anti-transpirant coating. The induction of callusing using leaf explants was significantly enhanced on medium containing 0.01 mg/l NAA and 2.0 mg/l benzylaminopurine. The unique carnivorous leaves that developed, but only facultatively, were only formed by regenerating plants on the supplemented medium and not on deficiency media. The leaves were shown to possess protease activity.