Abstract
Forests and woodlands in the West African Guineo-Sudanian transition zone contain many tree species that form symbiotic interactions with ectomycorrhizal (ECM) fungi. These fungi facilitate plant growth by increasing nutrient and water uptake and include many fruiting body-forming fungi, including some edible mushrooms. Despite their importance for ecosystem functioning and anthropogenic use, diversity and distribution of ECM fungi is severely under-documented in West Africa. We conducted a broad regional sampling across five West African countries using soil eDNA to characterize the ECM as well as the total soil fungal community in gallery forests and savanna woodlands dominated by ECM host tree species. We subsequently sequenced the entire ITS region and much of the LSU region to infer a phylogeny for all detected soil fungal species. Utilizing a long read sequencing approach allows for higher taxonomic resolution by using the full ITS region, while the highly conserved LSU gene allows for a more accurate higher-level assignment of species hypotheses, including species without ITS-based taxonomy assignments. We detect no overall difference in species richness between gallery forests and woodlands. However, additional gallery forest plots and more samples per plot would have been needed to firmly conclude this pattern. Based on both abundance and richness, species from the families Russulaceae and Inocybaceae dominate the ECM fungal soil communities across both vegetation types. The community structure of both total soil fungi and ECM fungi was significantly influenced by vegetation types and showed strong correlation within plots. However, we found no significant difference in fungal community structure between samples collected adjacent to different host tree species within each plot. We conclude that within plots, the fungal community is structured more by the overall ECM host plant community than by the species of the individual host tree that each sample was collected from.
Highlights
Throughout West Africa, forests, woodlands and savannas represent ecosystems of great biodiversity and economic importance as resources for food, fuel and fiber (Sinsin and Kampmann 2010)
While all ECM host trees were B. grandiflora at Kou and Kouadianikro, three host species were present at Kota-G, with Uapaca guineensis being co-dominant with B. grandiflora
Across the gallery forest sites, the total basal area was on average 28.2 m2/ ha, with ECM hosts making up 46–76% of total basal area (Table 1)
Summary
Throughout West Africa, forests, woodlands and savannas represent ecosystems of great biodiversity and economic importance as resources for food, fuel and fiber (Sinsin and Kampmann 2010). In many parts of the region, forest land is under pressure from grazing, conversion to cropland, fuelwood extraction and replacement by plantations of nonnative trees, often resulting in fragmentation of the landscape (Assédé et al 2020). These threatened ecosystems harbor a tremendous undescribed diversity of fungi, a group of organisms that is understudied in tropical regions, and so in West Africa (Gryzenhout et al 2012; Piepenbring et al 2020). Ectomycorrhizal (ECM) symbiosis is a mutualistic relationship in which fungal hyphae surround and grow between the cortical cells of specialized fine plant roots The relationship benefits both organisms, with the fungal partner providing nutrients in exchange for carbon from the plant partner. Increased knowledge about existing fungal biodiversity of wooded ecosystems is an important step towards building sustainable land use management that balances production and conservation
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call