Microbial community composition of long-term wheat-fallow and wheat-pea rotations in the dryland Pacific Northwest

The study objective was to investigate chemical and biological soil properties and the response of microbial communities when a rotation system changes from a simple wheat-fallow to a more diverse wheat-pea system, in the presence or absence of N fertilizers. We sampled soils from a long-term field experiment located near Pendleton, OR, USA. Measured soil properties included ammonium, nitrate, phosphate, total carbon, total nitrogen, total sulfur, active carbon, pH, microbial biomass carbon, and soil enzymes including beta-glucosidase, beta-glucosaminidase, acid phosphatase and arylsulfatase. Microbial community DNA was amplified for 16S V4 and LSU D2 regions and paired-end sequenced on the Illumina MiSeq platform.