Exploring the Potential of Four Novel Halotolerant Bacterial Strains as Plant-Growth-Promoting Rhizobacteria (PGPR) under Saline Conditions

Soil salinity, due to natural phenomena or human activities, alters the water potential, which in turn affects plant growth, negatively influencing their nutrient and uptake. Plant-growth-promoting rhizobacteria (PGPR) can be used counteract these negative effects, especially glycophytes. The aim of our study was characterize physiologically, genetically, biochemically novel halotolerant/halophilic bacteria isolated previous work. We evaluated plant-growth-promoting (PGP) features NaCl regulation’s roles them. In this regard, analysis based on 16S rDNA sequences confirmed that isolates are distinct bacterial strains, probably belonging new species, we named Bacillus sp. M21 M23 Halomonas QH23 QH24. literature, it is known many species genera produce factors regulating development, such as indole-3-acetic acid (IAA), ammonium, siderophores; efficiency promoting growth productivity also demonstrated vivo. newly strains exhibit different PGP highlighting how latter regulated by a strain-dependent manner. particular, main results showed production IAA QH23, M23, whereas promotes QH24, where strictly salt-dependent. Both ammonium only presence NaCl, directly correlated its concentration. opposite occurs salt reduces up ten times. Overall, underline halotolerance preferable, but not sufficient, condition for considering PGPR potentially useful applications aimed at improving tolerance crops saline soils.