The effect of Arbuscular mycorrhizal fungi on soil bacterial community during litter decomposition

Bacterial communities and non-saprophytic fungi co-occur in the soil, however the interaction between these two groups and their effects on litter decomposition has been largely unexplored. Here we aimed to investigate the effect of arbuscular mycorrhizal fungi (AMF) on soil bacterial community during litter decomposition using high resolution culture independent technique (Illumina sequencing). We found that most of the obtained OTUs from control and AMF inoculated soils belonged to the phylum of Proteobacteria, Acidobacteria and Actinobacteria. The compositions of soil bacterial community at phylum and class levels were slightly different according to either sampling time or AMF inoculation. Interestingly, we detected significant effects of the AMF inoculation and sampling time on soil bacterial community dynamics and structure using fine taxonomic resolution (i.e. genus or OTUs levels). However, overall soil bacterial OTU richness and diversity are relative stable and do not significantly influence neither by time nor AMF inoculation. OTU richness at phylum and class levels also showed consistent results with overall bacterial OTU richness. Our results thus support that AMF affect litter decomposition rate by altering bacterial community dynamics and structures at fine taxonomic resolution rather than bacterial OTU richness and diversity.