Effect of tillage and static abiotic soil properties on microbial diversity

• Published in: Applied soil ecology : a section of Agriculture, ecosystems & environment ecosystems & environment, 2018-12, Vol.132, p.135-145
• Main Authors: Legrand, Fabienne, Picot, Adeline, Cobo-Díaz, José Francisco, Carof, Matthieu, Chen, Wen, Le Floch, Gaétan
• Format: Article
• Language: English
• Subjects: Bioindicators; Fertilization; Life Sciences; Metabarcoding; Soil microbiota; Tillage
• ISSN: 0929-1393; 1873-0272
• DOI: 10.1016/j.apsoil.2018.08.016

•Soil microbial communities of 31 agricultural fields were profiled.•Minimum tillage and manure increased bacterial richness and evenness.•Fields under conventional tillage were enriched with oligotrophic Acidobacteria.•Hydrogenophaga, Mycoplana and Sphingopyxis were associated with manure application.•Fungal diversity was less sensitive to disturbance than bacterial communities. Agricultural soil microbial communities are largely impacted by agronomic practices, soil physicochemical properties and climatic conditions. To understand how these factors induce changes in fungal and bacterial communities in soil, we used a metabarcoding approach to profile the microbial communities of 31 agricultural wheat fields with maize as previous crop, representative of usual crop rotation in Brittany, France. Our results clearly highlighted the importance of tillage for both bacteria and fungi, with species richness and evenness significantly higher in fields under minimum tillage practices than in fields under conventional tillage, despite that the core microbiota was similar between fields under these two practices. The functional diversity of the bacterial communities, predicted using FAPROTAX, was also significantly higher in fields under minimum tillage notably that involved in nitrogen cycling (denitrification, respiration). We also observed that animal manure increased bacterial richness and evenness compared to chemical fertilization only. Interestingly, fungal diversity was less sensitive to disturbance than bacterial communities. We also identified taxa groups as potential bioindicators of a specific agronomic practice, such as the strong association between animal manure application and Hydrogenophaga, Mycoplana and Sphingopyxis, as well as the enrichment of oligotrophic Acidobacteria under conventional tillage.