Arbuscular mycorrhizal fungal communities are affected by disturbance and plant successional group during dryland ecological restoration

Arbuscular mycorrhizal fungi (AMF) are crucial for plant community recovery in degraded ecosystems, aiding in the establishment of plant communities and ecological succession. Using a nucleation-based restoration approach, this study compared the structure and composition of AMF communities between natural regeneration acceleration nuclei (restoration) and adjacent preserved Caatinga (reference) areas, and evaluated the influence of native Caatinga plant species at different successional stages on these fungi. Rhizospheric soil samples were collected from pioneer ( Cnidoscolus quercifolius, Jatropha molissima, and Cenostigma pyramidale ) and secondary ( Anadenanthera colubrina, Astronium urundeuva, and Manihot carthagenensis ) successional stages plants in restoration and reference areas. A total of 62 AMF taxa were identified, distributed across 14 families and 17 genera, with Glomeraceae (29 taxa) and Acaulosporaceae (10 taxa) as the most abundant families. Reference areas exhibited higher AMF richness (51 taxa) and glomerospore abundance than restoration areas (43 taxa), while 32 taxa (51%) were shared between both areas. Secondary successional stage plants showed greater AMF richness than pioneer plants, particularly in restoration areas. AMF community composition differed between areas and successional stages of plants and was significantly influenced by soil properties, especially Na, Mg, and pH. These results indicate that nucleation-based restoration promotes the short-term reestablishment of AMF communities, and that plant successional stage and soil properties shape AMF assembly in Caatinga restoration. • Arbuscular Mycorrhizal Fungi (AMF) aid in the recovery of degraded areas of Dry Forests in Brazil. • AMF community composition differs between reference Caatinga and restoration areas. • Secondary successional stage plants had higher AMF richness. • Soil properties shape AMF communities across successional stage. • Shared AMF taxa highlight the role of nucleation in community recovery.