Crop diversification improves the diversity and network structure of the prokaryotic soil microbiome at conventional nitrogen fertilization

Abstract Background Sustainable agriculture seeks to optimize the application of nitrogen (N) fertilizers reduce adverse economic and ecological effects. Crop diversification has been proposed increase efficiency N fertilization. An open question is how soil microbiome responds these beneficial practices. Methods In a field study we investigated effects mineral fertilizer with 0-control, conventional amount 150 kg ha −1 an excessive 250 on within diversified cropping system oil radish undersown ryegrass over period 2.5 years non-diversified control, both in rotation potato, winter rye maize. Results N-fertilizations crop rotations altered pH, but differences were less pronounced system. Compared species season, fertilization had influence abundance bacteria, archaea fungi. The showed much stronger effect archaeal than bacterial or fungal abundances, while microbial carbon use correlated strongly abundance. At end growing seasons, increased prokaryotic richness Shannon diversity response addition, greater N. supply, co-occurrence networks revealed denser complex structure Conclusions under rates positive by increasing their richness, diversity, promoting more elaborated network structure.