Moderate Phosphorus Addition to Field-Grown Bananas Enhanced Soil Microbial Enzyme Activities but Had Negligible Impacts on Bacterial, Fungal, and Nematode Diversity

On commercial banana (Musa spp.) plantations, soils are often supplemented with phosphorus (P) fertiliser to optimise production. Such additions may influence the diversity and function of soil microbial communities, which play important roles in P cycling and affect plant fitness. Here, we characterised the effects of P addition on the diversity and function of banana-associated microbial communities. P addition was associated with significant increases in soil P and the activities of alpha-glucosidase, chitinase, arylsulphatase, and acid phosphatase, but not beta-glucosidase or xylosidase. P addition also expedited bunch emergence and harvest, but did not influence fruit yield, plant height, or foliar P. There were no significant effects of P addition on the alpha or beta diversity of bacterial, fungal, and nematode communities, including members of the core microbiome. The only exceptions to this was an increase in the relative abundance of a Fusarium population in roots. These results indicate that phosphorus application to banana soils may stimulate microbial enzyme activities with minor or negligible effects on microbial diversity.