Results: Significant shifts in composition were observed between pre-plant and post-plant bacterial communities in 23 of the 40 most abundant orders but only one order (Nitrospirales) differed significantly between the two plant species treatments (Ag vs. Sc). Compared to pre-plant communities, post-plant communities increased significantly in alpha diversity (within community) but exhibited an overall decrease in beta diversity (between community), indicating that soil communities became more similar after growth of either Ag or Sc. Soil pH was the strongest predictor of bacterial community ordination, followed by percent carbon, organic matter, phosphorous, nitrogen, and potassium.
Conclusions: Overall, the relative lack of significant differences between the soil bacterial communities of Ag- and Sc-planted soils suggests that potential plant-species-specific effects are strongly modulated by growth conditions and edaphic soil characteristics.
Background and aims: Plant impacts on soil microbial community composition and function are believed to be important but remain poorly understood. We looked at the bacterial community effects of growing two different plant species in soils with differing plant growth histories.
Methods: Big bluestem (Andropogon gerardii: Ag) and cereal rye (Secale cereale: Sc) plants were grown in six soils with different planting and management histories for 14 weeks in a greenhouse study. Both prior to planting and harvesting, soil was collected for analysis. Bacterial community DNA was extracted and analyzed via 454 pyrosequencing and soil edaphic characteristics were also measured.
Bibliographical noteFunding Information:
Acknowledgements We thank Ronald Faber at the Sand Plain Research Farm for assistance with soil selection and history. We also thank Chris Wright at the Roy Carver Biotechnology Center for assistance with sample preparation for pyrosequencing. Also thanks to Laura Felice, Jon Anderson and Phil Manlick for assistance with plant harvesting and processing. Thanks to Pat Schloss and Sarah Westcott for advice with sequence processing via Mothur and to the Minnesota Supercomputing Institute for use of computing resources. This research was funded by National Science Foundation Microbial Observatories Program (Grant #9,977,907), United States Department of Agriculture Microbial Observatories (Grant # 2006-35,319-17,445), USDA-NIFA (Grant # 2011 67,019-30,330), and the University of Minnesota Agricultural Experiment Station Project (#MIN 22–018).
© 2014, Springer International Publishing Switzerland.
- Andropogon gerardii
- Secale cereale