Journal Article

Stimulation of Different Functional Groups of Bacteria by Various Plant Residues as a Driver of Soil Priming Effect

Boiry, Séverine, Mathieu, Olivier, Mougel, Christophe, Fontaine, Sébastien, Pascault, Noémie, Henault, Catherine, Lemanceau, Philippe, Ranjard, Lionel, Bachar, Dipankar, Maron, Pierre-Alain, Lévêque, Jean, Christen, Richard, Terrat, Sébastien, Péan, Michel, Kaisermann, Aurore

2013

Overview

The turnover of organic matter in soil depends on the activity of microbial decomposers. However, little is known about how modifications of the diversity of soil microbial communities induced by fresh organic matter (FOM) inputs can regulate carbon cycling. Here, we investigated the decomposition of two 13 C labeled crop residues (wheat and alfalfa) and the dynamics of the genetic structure and taxonomic composition of the soil bacterial communities decomposing 13 C labeled FOM and native unlabeled soil organic matter (SOM), respectively. It was achieved by combining the stable isotope probing method with molecular tools (DNA genotyping and pyrosequencing of 16S rDNA). Although a priming effect (PE) was always induced by residue addition, its intensity increased with the degradability of the plant residue. The input of both wheat and alfalfa residues induced a rapid dynamics of FOM-degrading communities, corresponding to the stimulation of bacterial phyla which have been previously described as copiotrophic organisms. However, the dynamics and the identity of the bacterial groups stimulated depended on the residue added, with Firmicutes dominating in the wheat treatment and Proteobacteria dominating in the alfalfa treatment after 3 days of incubation. In both treatments, SOM-degrading communities were dominated by Acidobacteria, Verrucomicrobia, and Gemmatimonadetes phyla which have been previously described as oligotrophic organisms. An early stimulation of SOM-degrading populations mainly belonging to Firmicutes and Bacteroidetes groups was observed in the alfalfa treatment whereas no change occurred in the wheat treatment. Our findings support the hypothesis that the succession of bacterial taxonomic groups occurring in SOM- and FOM-degrading communities during the degradation process may be an important driver of the PE, and consequently of carbon dynamics in soil.

• Publisher: Springer Science+Business Media,Springer US,Springer,Springer Nature B.V,Springer Verlag
• Subject: Acid soils / Acidobacteria / Agricultural sciences / Agricultural soils / Alfalfa / Bacteria / Bacteriology / Biomedical and Life Sciences / carbon / Carbon content / Carbon cycle / Cereal crops / Crop residues / Earth Sciences / ecological succession / Ecology / Environmental Management / Environmental Sciences / Firmicutes / Forest soils / Genetic structure / genotyping / Geochemistry / Geoecology/Natural Processes / Global Changes / Hydrology/Water Resources / Isotopes / Life Sciences / Microbial activity / Microbiology and Parasitology / Microcosms / Organic matter / Organic soils / Plant Sciences / Proteobacteria / ribosomal DNA / Sciences of the Universe / soil / Soil bacteria / Soil biochemistry / Soil microbiology / Soil microorganisms / Soil organic matter / Soil study / Soils / Stable isotopes / Taxonomy / Triticum aestivum / Verrucomicrobia / Verrucomicrobium / Wheat / Zoology