Investigation of plant growth promoting properties of endophytic and rhizospheric bacterial and fungal strains isolated from Origanum vulgare L. ssp. vulgare naturally grown in Erzurum

In this study, Origanum vulgare L. ssp. vulgare, a medicinal and aromatic plant, was collected from the Erzurum province and its surrounding areas, along with the root portion. The endophytic and rhizospheric bacteria and fungi inhabiting various parts of the plants, including roots, stems, and leaves, were investigated for their plant growth-promoting properties (PGP- plant growth promoter) after surface sterilization of the plants. The bacteria and fungi colonizing the plants were isolated and purified, and conventional experiments were conducted to test their PGP abilities. For bacteria, the tests included nitrogen fixation, phosphate solubilization, siderophore production, indole-3-acetic acid (IAA) production, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase production. For fungi, the tests included phosphate solubilization, siderophore production, and IAA production. Among the 90 bacterial isolates obtained, a subset of 18 isolates exhibiting superior PGP abilities, as well as 19 fungal isolates out of the 47 tested, were selected for further analysis. Molecular identification was performed by amplifying the 16S rRNA region for bacteria and the ITC PCR region for fungi using universal primers in PCR device. Subsequently, the obtained samples were subjected to sequence analysis, and BLAST analysis was performed in the NCBI database. The identified diagnostic results have been submitted and stored in the NCBI database.