Soil Physicochemical Properties And Bacterial Community Composition Jointly Affect Crop Yield

Balanced fertilization with N, P, and K fertilizers (NPK) is usually recommended to increase crop yield, while little is known on whether the effectiveness differs in soils with different fertilization histories. A greenhouse experiment grown with winter wheat (Triticum aestivum L.) and fertilized with NPK was conducted using soils that had been under five fertilization histories, including NPK, unbalanced fertilizers without one of the major elements (NP, PK, and NK), and an unfertilized treatment (Nil), for 18 yr. Wheat biomass and nutrient uptake from the PK treatment was 23-114% higher, from the NP was similar (except for N uptake), and from the NK and Nil was 14-58% lower, relative to the NPK treatment. Network analysis revealed positive associations of wheat biomass with available P (AvaP) and some specific taxa (i.e., Flavisolibacter and Pontibacter enriched in PK treatment and Microbacterium and Nocardioides depleted in NK and Nil treatments), besides positive associations between AvaP and Microbacterium and Nocardioides abundances. Genus Baccillus enriched in PK treatment was identified as the keystone taxa. These results suggest that significantly induced crop yield in PK treatment by a single season application of balanced fertilizers may be associated with higher AvaP and stimulation of microorganisms involved in nutrient cycling and crop growth promotion, while lower yield observed in NK treatment may be related to lower AvaP and suppression of microorganisms involved in soil P availability. Our findings implied that besides balanced fertilization, more strategies are required for quickly improving crop yield according to soil nature.