Genotypic and Phenotypic Characterization of EMP42 a PGPR Strain Obtained from the Rhizosphere of (Sweet Barrel).

Plant growth-promoting rhizobacteria (PGPR) are a group of bacteria that associate with the rhizosphere of plants; one of the most abundant bacterial genera in this ecological niche is , which is constantly expanding due to the emergence of new species such as , whose discovery in 2019 has led to the characterization of several strains from different environments but taxonomically related. The objective of this work was to phenotypically and molecularly characterize strain EMP42, isolated from the rhizosphere of . The strain EMP42 is able to use different substrates and reduce oxidative stress in plants. It is capable of improving growth parameters such as the number of inflorescences and the height of the aerial body of , as well as the germination and seedling survival of the cacti and . The genetic structure of EMP42 consists of a closed chromosome of 6.14 Mbp, and 61.1% GC content. It has 5572 genes, including those associated with PGPR activities, such as the ABCDE, SAP, ABPRU and ABC genes, among others, and three ncRNA loci, nine regulatory regions, five complete rRNA operons and three CRISPR-Cas loci, showing phylogenomic similarities with the reference strain B21-026. Therefore, this study contributes to the understanding of genomic diversity within and, particularly, highlights the potential application of strain EMP42 as a PGPR.