Isolation and Characterization of Salt-Tolerant Bacteria with Plant Growth-Promoting Activities from Salt-Affected Agricultural Fields

Abstract

Soil salinity poses a significant threat to agricultural productivity worldwide. In this study, we aimed to address this challenge by isolating and characterizing salt-tolerant bacteria with plant growth-promoting activities from salt-affected agricultural fields. Soil samples were collected from multiple salt-affected agricultural sites, and bacterial isolates were obtained using selective media. These isolates were subjected to screening for salt tolerance and plant growth-promoting activities, including indole-3-acetic acid (IAA) production, phosphate solubilization, and nitrogen fixation. Molecular characterization techniques, such as PCR and sequencing, were employed to identify the isolated bacteria.The results revealed a diverse array of salt-tolerant bacterial strains exhibiting robust plant growth-promoting activities. These strains demonstrated varying levels of salt tolerance, with some showing remarkable resilience to high salinity levels. Furthermore, selected isolates exhibited potent abilities to produce plant growth-promoting substances, including IAA, which can enhance plant growth and development under stressful conditions. Additionally, several isolates were proficient in solubilizing phosphate and fixing atmospheric nitrogen, further enhancing their potential for improving soil fertility and plant nutrition in saline environments. Greenhouse experiments were conducted to evaluate the effectiveness of selected bacterial isolates in promoting the growth of salt-sensitive crops under saline conditions. The results demonstrated that inoculation with salt-tolerant bacteria significantly improved plant growth parameters, including biomass accumulation, root length, and chlorophyll content, compared to untreated controls. These findings underscore the potential of salt-tolerant bacteria as biofertilizers for enhancing crop productivity in salt-affected agricultural areas.In conclusion, this study highlights the importance of harnessing the capabilities of salt-tolerant bacteria with plant growth-promoting activities to mitigate the adverse effects of soil salinity on crop production. The identification and characterization of such bacteria offer promising prospects for the development of sustainable agricultural practices that can contribute to global food security in the face of increasing soil salinity. Further research in this direction is warranted to fully exploit the potential of salt-tolerant bacteria in sustainable agriculture.