Sequencing Characterizes Bacterial Rhizosphere Communities of Biofuel Crops on Marginal Lands

The Science

Using a new high-capacity sequencing technology, Great Lakes Bioenergy Research Center researchers characterized the structure of bacterial communities living in the rhizosphere (microscopic zone surrounding roots) of corn, soybean, canola, sunflower, and switchgrass. Samples were taken from agricultural sites and adjacent native forest in four locations with different soil types in Michigan. Three of the locations were marginal lands unsuitable for conventional agriculture, and a fourth site served as an experimental control to evaluate crop yield and quality on nonmarginal land. Although bacterial communities from biofuel crops and forest were clearly differentiated, the communities grouped mainly by location rather than by crop species, and soil environment and land management were key factors influencing community structure. Although more limited in plant diversity, greater bacterial diversity was observed in the biofuel crop samples than in the forest samples. Species of Acidobacteria were the most abundant community members in the rhizospheres of all plants, yet no strains have been isolated for cultivation and characterization in the laboratory. Bacterial community composition and structure were assessed by 454 sequencing of the 16S rRNA gene. Bacterial diversity was higher in the agricultural sites compared to adjacent forest sites, indicating that the cultivation of those biofuel crops increased the rRNA diversity.


Jesus, E. C., E. Susilawati, S. L. Smith, Q. Wang, B. Chai, R. Farris, J. L. M. Rodrigues, K. D. Thelen, and J. M. Tiedjie. 2010. “Bacterial Communities in the Rhizosphere of Biofuel Crops Grown on Marginal Lands as Evaluated by 16S rRNA Gene Pyrosequences,” Bioenergy Research 3, 20–27. DOI:10.1007/s12155-009-9073-7.