S04 - Session P1 - New Tools II - Initiation to the in vitro culture of Pterocarpus erinaceus Poir. in Togo

Authors: Benziwa Johnson, Marie-Luce Quashie, A. Raoufou Pierre Radji *, Kodjo Djidjolé Etsé

Pterocarpus erinaceus Poir., a forest species with high socio-economic potential and over-exploited, is studied to contribute to the improvement of knowledge essential to its sustainable production and thus ensure its culture. As a result, seeds and softwood cuttings from greenhouse-grown trees with multi-performing criteria (Plus Trees) are employed. Surface disinfected explants were germinated in vitro on Murashige & Skoog medium (MS0) with sucrose 3% (m/v) and solidified with agar 0.8% (m/v) for seeds, and supplemented or not with auxin-type growth regulators (MS-AIB) or cytokinin (MS-BAP) for cuttings. First, all vitroplants were cultivated on MS0, and the germination, growth, and resumption of development of single-node segments extracted from these vitroplants (transplanting) were all monitored. After that, the responses of Plus Trees softwood cuttings to the addition of auxins/cytokinins (MS-BAP and MS-AIB) to the MS0 medium were assessed. The results show that establishing an in vitro culture using seeds is successful, with a low contamination percentage (0-6%) and a germination capability of 90%. The growth of seedlings from germination over 12 weeks is sluggish yet consistent. There is also a caulinar development after the transplanting of single-node segments from these vitroplants on the same medium. The Plus Trees softwood cuttings show a positive reactivity, as illustrated by a caullogenesis, with the medium MS0, which proves to be effective in opening axillary buds and their growth into leafy shoots. The 0.1 mg/l AIB+0.5 mg/l BAP hormonal combinations improve budding percentages. Morphogenesis was greatest in the 0.5 mg/l AIB-containing medium. However, no evidence of rhizogenesis was found in the culture conditions tested. suggestions Pterocarpus erinaceus Poir. is a tree with great socio-economic potential that is currently overexploited. the aim of the proposed research was to ensure the sustainable production of planting material and its exploitation. To this end, seeds and softwood cuttings from greenhouse-grown Plus trees were used. Surface-disinfected seeds were germinated in vitro on Murashige & Skoog medium (MS0) containing sucrose 3% (w/v) and agar 0.8% (w/v). Thereafter, the response of single budded nodules to the addition of auxins/cytokinins IBA/BAP to the MS0 medium was evaluated. The results show that the establishment of an in vitro culture using seeds is successful, with a low infection rate (0-6%) and a germination capacity of 90%. The growth of seedlings from germination for 12 weeks is slow but consistent. MS0, was found to be effective for the outgrowth of axillary buds to leaf forming shoots. The hormonal combinations 0.1 mg/l AIB+0.5 mg/l BAP improved the bud formation rate. Although growth was best with 0.5 mg/l IBA, no rhizogenesis was observed.