Assembly of Endophytic Communities of Setaria viridis Plants when Grown in Different Soils and Derived from Different Seeds

The association of the plant microbiota is a successional
process that starts with the seed and its intrinsic microbiota. The
recently reported relevance of seeds as carriers of microbiota
has encouraged investigations of the assembly of these
communities in different tissues. Here, we address the
contributions of both seed and soil bacterial microbiota in the
assembly of communities within endospheres of adult plants by
16S ribosomal RNA gene-based Illumina sequencing.
Surface-sterilized seeds of the model plant Setaria viridis were
sown in sterile conditions and seedlings were transferred onto
either their native soil or a foreign soil. Soil-derived bacterial
colonizers contributed to the highest portion of endophytic
microbiota, with varying community composition depending on
the cultivation soil. In contrast, the contribution of seed
microbiota in those of adult plants was less evident. Moreover,
seedlings grown in their native soils resulted in plants with
consistent endophytic assemblages, whereas a dramatic
increase in variability was observed for rhizosphere and
endophytic root communities of plants grown in foreign soils.