, vol. 2, issue 1, pp. 186, 2025.
Drastic consequences of climate change necessitate exploring plant-microbiota of arid desert ecosystems for potential candidates recommended for future microbiota –mediate strategies of stressed agriculture. The prevalent xerophytes (Amaranthaceae, Compositae, Cyperaceae, Gramineae, Plantaginaceae, Scrophulariaceae, and Zygophyllaceae) were tested for culturable associated microbiota. Representative isolates were subjected to PGP functions, API-profiling and 16S rRNA genes sequencing. Xerophytes hosted dense populations of culturable microbiota, ecto-/endo-rhizosphere (> 103–107 CFUs g−1 root). API microtube analysis confirmed the predominance of representative genera of Gram-positive/negative bacteria. Isolates expressed multi-functional PGP traits, e.g. nitrogenase activity, indole acetic acid production, P/K- solubilization, ammonia production, salt tolerance, and effective/wide enzymatic activities. Based on 16S rRNA gene sequencing, the dominant phyla were Firmicutes, Gammaproteobacteria and Alphaproteobacteria. Firmicutes represented in ecto-rhizosphere (Bacillus rugosus, B. cereus, and B. altitudinis) and endo- rhizosphere (B. halotolerans, B. safensis subsp. safensis, B. siamensis, B. licheniformis and Brevibacillus parabrevis). Gammaproteobacteria presented in ecto-rhizosphere as Pseudomonas aeruginosa, Ps. hibiscicola, Ps. monteilii, Kosakonia cowanii and Serratia liquefaciens and in endo-rhizosphere as Pantoea vagans, P. conspicua and Stenotrophomonas maltophilia. Alphaproteobacteria, Azospirillum zeae, Azospirillum oryzae and Agrobacterium salinitolerans, were present in ecto-rhizosphere. Conformity among API profiling and 16S rRNA gene sequencing on the genus level (> 58%) indicated the reliability of API profiling as pre-identification scheme. It is concluded that the present study provides additional information regarding microbiota associated with xerophytes. Beside their taxonomic diversity, they are of potential/ functional impact that recommend their use as candidates of synthetic communities (SynCom) for the modification of economic crops introduced to arid deserts.