Arbuscular mycorrhizal fungal communities and relationship with edaphic factors in the rhizospheric soil of Fabaceae in semi-arid South Africa

Knowledge of the arbuscular mycorrhizal (AM) fungal diversity in semi-arid soils is crucial to understanding the ecological functions of AM fungi, exploiting their potential for plant and ecosystem sustainability, and informing effective conservation actions. However, in South Africa, the biodiversity of AM fungi in the soil and influencing factors are understudied. Thus, we assessed the AM fungal diversity and community composition and their association with edaphic factors in rhizospheric soils of eleven indigenous legume species occurring in two South African provinces with contrasting elevations, Gauteng and Mpumalanga. High-throughput sequence analysis of the 18S rRNA gene detected 322 and 335 AM fungal amplicon sequence variants in Gauteng and Mpumalanga, respectively; Glomus was the dominant genus, accounting for a mean relative abundance of approximately 72%–90 % across provinces. AM fungal richness and diversity varied significantly among the different legume species. There was no marked compositional difference in AM fungal communities among legumes and between provinces, but available phosphorus and soil texture significantly influenced the community composition. The data contribute to the knowledge of biodiversity and likely ecological drivers of the AM fungal community structure in semi-arid soils and suggest no host specificity and altitudinal-induced effects on rhizosphere AM fungal diversity in indigenous legumes of South Africa.