The main goal of this work was to describe the mycorrhizal status, AM or ECM or dual AM and ECM or nonmycorrhizal (NM), of different trees species in five coastal humid forests located along the eastern coast of Madagascar. Identification of the plants was carried out by carefully tracing the root system in the field. Several field collection surveys were under-taken and the biological material was examined in laboratory conditions to check the mycorrhizal status of roots and to identify sporophores. (Résumé d'auteur)