Soil Microbiome During Corn Production as Influenced by Soil Order and
Nitrogen Fertilization
Abstract
Maintaining a healthy soil microbiome is important for key soil
functions and plant growth. However, little is known about temporal
changes in soil microbial communities across different soils and
nitrogen fertilization in production soils. The aim of this
investigation was to determine soil bacterial and fungal baseline
communities and seasonal changes in cornfields, under contrasting soil
orders with and without nitrogen fertilization. Three Missouri soil
orders (Entisol, Alfisol, and Mollisol) and two nitrogen fertilizer
rates (0 and 225 kg nitrogen ha-1) were used for this research. Soil
samples (0-5 and 5-15 cm) were taken six times during the season,
starting prior to planting up to the R2 corn growth stage. Samples were
used to determine bacterial and fungal abundancies and biomass. Soil
characteristics (e.g., CEC, pH, organic matter) and nitrogen
fertilization showed significant but minor influence on bacterial
abundance and biomass, while soil order and corn growth stage had major
influence. Each soil order had a distinct and significantly different
bacterial and fungal community. Soil depth significantly influenced all
Beta diversity metrics, and bacterial and fungal biomass were greater in
the 0-5 cm depth. No microbial interactions influenced corn growth more
than nitrogen. Though strong relationships between microbes and soil and
plant health have been shown, linkages of microbiome information to
agronomic decisions are rare. Before developing soil microbial
information based decision aids for farmers, longer temporal sampling in
more growing environments are needed to identify links between
management practices and microbial information.