Erwinia plantamica sp. nov., a Non-Phytopathogenic Bacterium Isolated from the Seedlings of Spring Wheat (Triticum aestivum L.)

<i>Erwinia</i> are widely known as phytopathogenic bacteria, but among them, there are also plant-friendly strains that can promote plant growth (PGPR). The <i>Erwinia</i>-like strain OPT-41 was isolated from <i>Triticum aestivum</i> seedlings as a potential PGPR. The cells (0.9-1.3 × 1.5-3.1 µm) of this microorganism are Gram-negative, rod-shaped, motile (with peritrichous flagella), and non-spore- and non-capsule-forming. The 16S rRNA gene sequence analyses showed it is located in the <i>Erwiniaceae</i> family and has a pairwise similarity above the species delineation threshold of 98.65% with several of its members: <i>Erwinia tasmaniensis</i> (99.21%), <i>Candidatus</i> Pantoea bathycoeliae (98.93%), <i>Pantoea agglomerans</i> (98.87%), <i>Erwinia endophytica</i> (98.83%), <i>Erwinia persicina</i> (98.82%), <i>Erwinia billingiae</i> (98.76%) and <i>Erwinia aphidicola</i> (98.75%). Whole genome-based taxonomy performed on the Type (Strain) Genome Server clarified the status of strain OPT-41, detecting it as a potential new species in the genus <i>Erwinia</i>. The microorganism under study was the most closely related to the type strain of <i>E. phyllosphaerae</i>, demonstrating 27.2% similarity in dDDH, 83.44% similarity in OrthoANIu, and 1.9% difference in G+C content. The major fatty acids of strain OPT-41 were 9 C_16:1, C_14:0, and C_16:0. A combination of genome-based taxonomy and traditional polyphasic taxonomy clearly indicated that strain OPT-41 belongs to a novel <i>Erwinia</i> species, for which the name <i>E. plantamica</i> sp. nov was proposed. OPT-41 (=IBPPM 712=VKM B-3873D=CCTCC AB 2024361) has been designated as the type strain. In addition, OPT-41 was found to have low degradation potential for host plant pectins and proteins and be friendly in <i>Triticum aestivum</i> and <i>Hordeum vulgare</i> crops.