In vitro vegetative multiplication of Nauclea diderrichii (De Wild &T. Durand) Merrill, an endangered forest species in Togo

Nauclea diderrichii, is a forest species whose seeds germination is difficult in its biotope. Its overexploitation for its very resistant wood against the attacks leads to its disappearance in Togo. In vitro micropropagation trials were carried out for his faster and massive regeneration. In vitro seedlings apexes had been cultivated on four media (MS, ½ MS, WPM and ½ WPM). The high ionic concentration in macroelements in the culture medium is harmful to N. diderrichii's seedlings development. Complete Woody Plant Medium (WPM) (41,54mM) allowed a better growth of the seedlings during initiation phase. Among both cytokinins (BAP and Kinetin) used, BAP at 2 mg/L, has gave a better multiplication rate (13,65d ± 5.71 nodes/seedling). Among three auxins (IBA, NAA and 2,4-D) used at 0,1mg/L, IBA has gave seedlings with vigorous roots which are better appropriate for weaning, that those obtained with NAA. 2,4-D produced only calluses. The weaning of the seedlings, realized on vermiculite was succeeds at 100%. Thus fast and massive multiplication of N. diderrichii can be done in vitro on WPM added with BAP at 2 mg/L. IBA at 0,1mg/L is the auxin which is better appropriate for improvement of seedlings' rooting.