Synergy between Arbuscular Mycorrhizal Fungi and Rhizosphere Bacterial Communities Increases the Utilization of Insoluble Phosphorus and Potassium in the Soil by Maize

Arbuscular mycorrhizal (AM) fungi can enhance plant uptake
of phosphorus
(P) and potassium (K), but it is not yet clear whether rhizosphere
bacteria can enhance the ability of AM fungi to acquire insoluble
P and K from the soil. Here, pot experiments confirmed that AM fungus-promoted
insoluble P and K uptake by plants requires rhizosphere bacteria.
The changes of rhizosphere bacterial communities associated with AM
fungi were explored by 16S rRNA amplicon sequencing and metagenomic
sequencing. Five core bacteria genera identified were involved in
P and K cycles. Synthetic community (SynCom) inoculation revealed
that SynCom increased soil available P and K and its coinoculation
with AM fungi increased P and K concentration in the plants. This
study revealed that AM fungi interact with rhizosphere bacteria and
promote insoluble P and K acquisition, which provided a foundation
for the application of AM fungal–bacterial biofertilizers and
was beneficial for the sustainable development of agriculture.