Halophilic bacteria are remarkable microorganisms that excel in hypersaline environments. Their significant potential in various fields, such as industry and agriculture, positions them as vital players in advancing technological and ecological efforts.
In this study, three bacterial strains (QSLA1, QSLA2, and QSLA3) were successfully isolated from solar saltern ponds, attached to Qarun Lake, Fayoum governorate, Egypt, using nutrient agar (NA) culture medium derived from pond water. Morphological and physiological characterization revealed that these isolates are rod-shaped, gram-negative, catalase-positive, and motile. All isolates were identified as not spore-forming bacteria. The halo tolerance assay demonstrated that QSLA1 and QSLA2 are extremely halophilic, whereas QSLA3 is classified as moderately halophilic. Through 16S rRNA sequence analysis, it was determined that QSLA1 shares 91.26% similarity with Halomonas sp. RS-17, while QSLA2 exhibits 96.6% similarity with Halomonas sp. strain LR2-3. QSLA3 shows even greater similarity at 97.33% to Halomonas sp. GQ30. All isolates are capable of producing indole-3-acetic acid (IAA), but only QSLA2 has the ability to fix atmospheric nitrogen and solubilize insoluble phosphate. Additionally, QSLA1 demonstrates antifungal activity against Fusarium oxysporium f.sp. lycopersici in vitro under saline environment. Given these promising traits, researchers explored the potential of QSLA1 as a bio-control agent under greenhouse conditions at 1.5% salinity.
These findings suggest that these bacterial strains could be used to develop sustainable agricultural practices, enhancing crop yields and reducing the reliance on chemical fertilizers and pesticides. Future applications of these strains could provide a valuable solution for improving agricultural productivity in saline environments.
Mousa, A.A.A., Mahmoud, W.H., Elsaied, H.E. et al. Halomonas sp for sustainable agriculture a potential halo bio fertilizer for tomato plants with biocontrol activity against Fusarium wilt under saline environments. Sci Rep 15, 30748 (2025). https://doi.org/10.1038/s41598-025-12974-9
Source: Nature Magazine
