Quality seed production to optimize the success of reforestation and agroforestry based on local indigenous forest species: case of Khaya senegalensis (Meliaceae) and Parkia biglobosa (Fabaceae) in West Africa

Abstract Seed size is a key factor that can affect the regeneration process of plant populations. This study aims to identify efficient seeds that can optimise the cultivation of two overexploited native forest species in Côte d'Ivoire, namely Khaya senegalensis and Parkia bliglobosa. Sets of 1080 seeds per species were tested for their germination and seedling vigour in two distinct environments (dry and humid) in Côte d'Ivoire. The results showed that, for optimized germination, large seeds were preferable for Khaya senegalensis while for Parkia biglobosa, on the contrary, small and medium seeds were preferable. However, the most vigorous seedlings were generated by germinating large seeds regardless of species and study site. In this case, pre-treatment tests on large seeds in Parkia biglobosa are possible to improve their germination performance. Large seeds appear to be the best candidates for high quality, high performance seeds that can optimise the cultivation of Khaya senegalensis (0.25-0.37g) and Parkia biglobosa (0.25-0.37g) in Côte d'Ivoire. They can be provided to farmers to assist in the success of replanting programmes (reforestation and agroforestry) using the target species in Côte d'Ivoire. These results can contribute to the sustainable management of the target species and serve as a basis for restructuring forest regeneration policy in Côte d'Ivoire.