Characterization of the arbuscular mycorrhizal fungal community associated with rosewood (Pterocarpus tinctorius Welw.) in Miombo forests, Democratic Republic of Congo

Abstract Understanding the dynamics of arbuscular mycorrhizal fungal (AMF) in response to land use change is crucial for the restoration of degraded forests. Here, we describe the diversity and structure of AMF communities in roots of Pterocarpus tinctorius sampled from aluminium- and iron-rich agricultural and forest fallow soils. AMF in root samples were identified by sequencing the large subunit region of the rRNA gene. A total of 30 operational taxonomic units (OTUs) were recovered, most of which were new to science. These OTUs belonged to five genera namely Rhizophagus, Dominikia, Glomus, Sclerocystis and Scutellospora. AMF species richness was significantly influenced by soil properties and tree density, with a low mean value (3.2) observed in acidic soils with high Al and Fe. Indicator species analyses revealed nine AMF OTUs as indicators of base saturation (4 OTUs), high aluminium (3 OTUs) and iron (2 OTUs). OTUs positively correlated with acidity (1 OTU), iron and available phosphorus (2 OTUs) were assigned to the genus Rhizophagus, and indicated Al and Fe tolerance. The results show that leguminous trees in tropical dry forests are a potential reservoir of unknown AM fungal species. The baseline data obtained in this study opens new avenues for future studies, including the use of indigenous AMF-based biostimulants to implement ecological revegetation programs and improve land use.