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Soil fungi associated with plant roots, notably ectomycorrhizal (EcM) fungi, are central in above- and below-ground interactions in Mediterranean forests. They are a key component in soil nutrient cycling and plant productivity. Yet, major disturbances of Mediterranean forests, particularly in the Southern Mediterranean basin, are observed due to the greater human pressures and climate changes. These disturbances highly impact forest cover, soil properties and consequently the root-associated fungal communities. The implementation of efficient conservation strategies of Mediterranean forests is thus closely tied to our understanding of root-associated fungal biodiversity and environmental rules driving its diversity and structure. In our study, the root-associated fungal community of Q. suber was analyzed using high-throughput sequencing across three major Moroccan cork oak habitats. Significant differences in root-associated fungal community structures of Q. suber were observed among Moroccan cork oak habitats (Maâmora, Benslimane, Chefchaoun) subjected to different human disturbance levels (high to low disturbances, respectively). The fungal community structure changes correlated with a wide range of soil properties, notably with pH, C:N ratio (P = 0.0002), and available phosphorus levels (P = 0.0001). More than 90 below-ground fungal indicators (P < 0.01)–either of a type of habitat and/or a soil property–were revealed. The results shed light on the ecological significance of ubiquitous ectomycorrhiza (Tomentella, Russula, Cenococcum), and putative sclerotia-associated/ericoid mycorrhizal fungal taxa (Cladophialophora, Oidiodendron) in the Moroccan cork oak forest, and their intraspecific variability regarding their response to land use and soil characteristics.

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-A survey of arbuscular mycorrhizal (AM) fungi was conducted in seven Tetraclinis woodlands. Microscopic analysis of the mycorrhizal status of T. articulata (Vahl) Masters roots revealed that all samples formed only AM, and no ectomycorrhizal fungi were detected. The mycorrhizal colonisation level was generally high (more than 80%), thus reflecting the mycotrophic nature of T. articulata. A "Paris-type" mycorrhizal structure was noted in all studied samples. The number of AM fungal spores detected in field-collected soils was relatively high. All recovered spores belonged to the Glomineae order, represented by Glomaceae and Acaulosporaceae families. Two groups were dominant: the first one included small (90 µm), hyaline, white to dark-yellow spores, and the second involved large (295 µm), light orange to dark orangebrown spores. The morphological characters indicated that the spore populations consisted of 3-6 morphotypes. The Glomus genus was represented by five species, i.e. Glomus aggregatum, Glomus constrictum, Glomus sp. 1, Glomus sp. 2, and Glomus sp. 3, while the Acaulospora genus was represented by only one unidentified species. diversity / tetraclinis woodlands / "Paris-type" arbuscular mycorrhizae / Glomus / Acaulospora Résumé -Diversité des champignons mycorhiziens arbusculaires dans les forêts de Tetraclinis articulata (Vahl) Masters au Maroc. La présence des champignons mycorhiziens arbusculaires (CMA) a été étudiée dans sept tetraclinaies marocaines. Les examens microscopiques des racines de T. articulata (Vahl) Masters ont révélé la présence, dans tous les échantillons, des endomycorhizes arbusculaires ; aucune ectomycorhizes n'a été détectée. Le taux d'infection par les endomycorhizes à arbuscules a été très élevé (plus de 80 %), indiquant le caractère mycotrophique de l'espèce. La structure mycorhizienne observée dans tous les échantillons analysés est de type « Paris ». Le nombre de spores de CMA isolées à partir des différents sols est relativement élevé. Toutes les spores appartiennent à l'ordre des Glomineae, représenté par deux familles : Glomaceae et Acaulosporacea. Deux groupes sont dominants : le premier groupe renferme des spores hyalines, blanches à jaunes foncées et de petites tailles (90 µm en moyenne) et le second correspond à des spores orange-claires à orange foncées et de grandes tailles (295 µm en moyenne). Les caractères morphologiques indiquent que les populations de spore comportent 3 à 6 morphotypes selon le site. Le genre Glomus, le plus dominant, est représenté par cinq espèces -Glomus aggregatum, Glomus constrictum, Glomus sp. 1, Glomus sp. 2, et Glomus sp. 3 -alors que le genre Acaulospora est représenté par une seule espèce non identifiée. diversité / tetraclinaies / mycorhizes à arbuscules type « Paris » / Glomus / Acaulospora