Influence of different environments on germination parameters and seedling morphology in Khaya senegalensis (Desr.) A. Juss (Meliaceae)

Khaya senegalensis is one of the largest and most majestic trees in Africa. Overexploited for its precious wood and medicinal values, the natural stands of this species are in danger of extinction in Cote d'Ivoire. Its sustainable management through regeneration techniques and assessment of its degree of adaptation to the changing climate is necessary. The aim of this study is to evaluate the effect of different environments on seedling germination and development in Khaya senegalensis. A total of 2160 seeds from different mother plants and 540 individuals from seed germination were selected and evaluated. The trials were conducted on three sites that were distinct by their microclimate (two nurseries in Cote d'Ivoire and one greenhouse in France). Analysis of variance showed that germination and morphology parameters were not influenced by the characteristics of the mother plants used (p > 0.05), but rather by the study sites (P < 0.05). The stable and controlled greenhouse climate was more advantageous for latency time (12.66 ± 0.80 days), germination delay (16.96 96 ± 0.54 days), germination speed (19.66 ± 2.95 days), germination duration (10.83 ± 2.27 days) and germination rate (88.88 ± 7.97) with more vigorous sowing than the other two sites. The results showed in general that the higher the height of the seedlings, the thicker the diameter of the seedlings (r = 0.796) and the higher the number of leaves (r = 0.946). This savannah species is native to the arid zones of Africa, but this study highlighted its adaptive potential to changing and different climates. These results are decision support tools for the regeneration of native pioneer forest species with high agroforestry potential and socio-economic importance such as Khaya senegalensis. This study could be extended to other species in order to restore disturbed ecosystems