The consensus approach suggested that there is a need for taxonomic amendments of the orders Frankiales and Micrococcales. (C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“Mineral amendment (i.e. calcium, phosphorous, potassium and/or magnesium) is a management practice used in forestry to improve nutrient availability and recover soil fertility, especially in nutrient-poor forest ecosystems. However, whether this amendment can lead to modifications of the soil characteristics and an improvement in tree growth, and its impact on the soil bacterial communities, especially the MDV3100 purchase mineral weathering bacterial

communities, remains poorly documented. In this study, we investigated the short-term impact of a mineral amendment on the taxonomic and functional structure

of the mineral weathering bacterial communities. To do this, a plantation of four-year old oak (Quercus petraea) trees amended with or without dolomite [CaMg(CO3)(2)] was established in the experimental forest site of Breuil-Chenue, which is characterized by an acidic soil and a low availability of calcium and magnesium. Three years after amendment, soil samples were used to isolate bacteria as well as to determine the soil characteristics and the metabolic potentials of these soil microbial communities. Based on a bioassay for quantifying the solubilisation of inorganic phosphorous, we demonstrate that the bacterial isolates selleck compound coming from the non-amended ALOX15 bulk soil were significantly more efficient

than those from the amended bulk soil. No difference was observed between the bacterial isolates coming from the amended and non-amended rhizospheres. Notably, the taxonomic analyses revealed a dominance of bacterial isolates belonging to the Burkholderia genus in both samples. Overall, our results suggest that the bioavailability of nutritive cations into soil impacts the distribution and the efficacy of mineral weathering bacterial communities coming from the soil but not those coming from the rhizosphere. (C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“The taxonomic affiliations of nineteen root-nodule bacteria isolated from the common bean (Phaseolus vulgaris L.) in Mexico, Ecuador and Brazil were investigated by analyses of 16S rRNA and of four protein-coding housekeeping genes. One strain from Mexico could be assigned to Rhizobium etli and two from Brazil to Rhizobium leucaenae, whereas another from Mexico corresponded to a recently described bean-nodulating species-level lineage related to R. etli and Rhizobium phaseoli. Ten strains isolated in Ecuador and Mexico corresponded to three novel Rhizobium lineages that fall into the R. phaseoli/R. etli/Rhizobium leguminosarum clade.