AUTHOR=Singer Esther , Bonnette Jason , Woyke Tanja , Juenger Thomas E. 

TITLE=Conservation of Endophyte Bacterial Community Structure Across Two Panicum Grass Species

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.02181

DOI=10.3389/fmicb.2019.02181

ISSN=1664-302X

ABSTRACT=<p><italic>Panicum</italic> represents a large genus of many North American prairie grass species. These include switchgrass (<italic>Panicum virgatum</italic>), a biofuel crop candidate with wide geographic range, as well as <italic>Panicum hallii</italic>, a close relative to switchgrass, which serves as a model system for the study of <italic>Panicum</italic> genetics due to its diploid genome and short growth cycles. For the advancement of switchgrass as a biofuel crop, it is essential to understand host microbiome interactions, which can be impacted by plant genetics and environmental factors inducing ecotype-specific phenotypic traits. We here compared rhizosphere and root endosphere bacterial communities of upland and lowland <italic>P. virgatum</italic> and <italic>P. hallii</italic> genotypes planted at two sites in Texas. Our analysis shows that sampling site predominantly contributed to bacterial community variance in the rhizosphere, however, impacted root endosphere bacterial communities much less. Instead we observed a relatively large core endophytic microbiome dominated by ubiquitously root-colonizing bacterial genera <italic>Streptomyces</italic>, <italic>Pseudomonas</italic>, and <italic>Bradyrhizobium</italic>. Endosphere communities displayed comparable diversity and conserved community structures across genotypes of both <italic>Panicum</italic> species. Functional insights into interactions between <italic>P. hallii</italic> and its root endophyte microbiome could hence inform testable hypotheses that are relevant for the improvement of switchgrass as a biofuel crop.</p>