Unique Bacterial Phyla in Ecosystems That Was Under Native Vegetation, Conservation Reserve Program (CRP), or Continuous Winter Wheat Cultivation.

Microorganisms are key players in nutrient cycling and ecosystem functions. Studies were conducted to determine diversity, richness, and uniqueness of soil bacteria communities in ecosystems that was undisturbed for >50 years (Native), under CRP for 12 years, or under long-term continuous winter wheat (Triticum aestivum L.). A total of 4196, 6405, and 8109 sequences of 16S rRNA gene fragments were obtained from Native, CRP, and Wheat, respectively. These sequences belonged to a combined total of 13 phyla, 31 classes, 59 orders, 108 families, 172 genus, or 286 species. The number of each taxonomic rank was higher in Wheat than Native or CRP, indicating that the richness of bacterial community was promoted by cultivation of wheat. Of the 286 species detected, 122, 134, and 199 species were detected in Native, CRP, and Wheat, respectively. In two independently replicated experiments, nine out of 13 detected phyla were common to all systems tested; one phylum, Nitrospirae ,  was common to both CRP and Wheat; Spirochaetes was unique to Native; Planctomycetes and Tenericutes were unique to CRP; and three including Deinococcus-Thermus, Gemmatimonadetes, and Chlamydiae were unique to Wheat. As one of the most abundant bacteria phyla present in the gut fluid of termites, presence of Spirochaetes may suggest the predominance of termites in native prairie soils. Unique microbial sequences in an ecosystem could indicate unique food web components that were drivers of the ecosystem function.