AUTHOR=Fan Di , Schwinghamer Timothy , Liu Shuaitong , Xia Ouyuan , Ge Chunmei , Chen Qun , Smith Donald L. 

TITLE=Characterization of endophytic bacteriome diversity and associated beneficial bacteria inhabiting a macrophyte Eichhornia crassipes

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1176648

DOI=10.3389/fpls.2023.1176648

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>The endosphere of a plant is an interface containing a thriving community of endobacteria that can affect plant growth and potential for bioremediation. <italic>Eichhornia crassipes</italic> is an aquatic macrophyte, adapted to estuarine and freshwater ecosystems, which harbors a diverse bacterial community. Despite this, we currently lack a predictive understanding of how <italic>E. crassipes</italic> taxonomically structure the endobacterial community assemblies across distinct habitats (root, stem, and leaf).</p></sec><sec><title>Methods</title><p>In the present study, we assessed the endophytic bacteriome from different compartments using 16S rRNA gene sequencing analysis and verified the <italic>in vitro</italic> plant beneficial potential of isolated bacterial endophytes of <italic>E. crassipes</italic>.</p></sec><sec><title>Results and discussion</title><p>Plant compartments displayed a significant impact on the endobacterial community structures. Stem and leaf tissues were more selective, and the community exhibited a lower richness and diversity than root tissue. The taxonomic analysis of operational taxonomic units (OTUs) showed that the major phyla belonged to Proteobacteria and Actinobacteriota (&gt; 80% in total). The most abundant genera in the sampled endosphere was <italic>Delftia</italic> in both stem and leaf samples. Members of the family Rhizobiaceae, such as in both stem and leaf samples. Members of the family Rhizobiaceae, such as <italic>Allorhizobium- Neorhizobium-Pararhizobium-Rhizobium</italic> were mainly associated with leaf tissue, whereas the genera <italic>Nannocystis</italic> and <italic>Nitrospira</italic> from the families Nannocystaceae and Nitrospiraceae, respectively, were statistically significantly associated with root tissue. <italic>Piscinibacter and Steroidobacter</italic> were putative keystone taxa of stem tissue. Most of the endophytic bacteria isolated from <italic>E. crassipes</italic> showed <italic>in vitro</italic> plant beneficial effects known to stimulate plant growth and induce plant resistance to stresses. This study provides new insights into the distribution and interaction of endobacteria across different compartments of <italic>E. crassipes</italic> Future study of endobacterial communities, using both culture-dependent and -independent techniques, will explore the mechanisms underlying the wide-spread adaptability of <italic>E. crassipes</italic>to various ecosystems and contribute to the development of efficient bacterial consortia for bioremediation and plant growth promotion.</p></sec>