@article{open3236,
          volume = {15},
          number = {1},
           month = {April},
          author = {Nitish Kumar and Bhupinder Kaur and Deepika Sharma and Suresh Korpole and Shardulya Shukla and Pushpender Bhardwaj and Manoj Kumar Patel and Somen Acharya and Madhu Khatri and Shweta Saxena},
           title = {Impact of altitudinal variations on plant growth dynamics, nutritional composition, and free living rhizospheric N2 fixing bacterial community of Eruca sativa},
         journal = {Sci. Rep.},
           pages = {13839},
            year = {2025},
        keywords = {Eruca sativa ; Bio-fertilizer; Diazotrophs; Dietary nitrate; High altitude; Sustainable agriculture},
             url = {http://crdd.osdd.net/open/3236/},
        abstract = {High-altitude environments present unique abiotic stresses, yet their impact on the growth, nutritional quality, and rhizospheric interactions of E. sativa remains underexplored. Here, we investigate the altitudinal variations in growth dynamics, nutritional composition, and rhizospheric free-living N2-fixing bacteria (NFBs) of E. sativa (Arugula) grown at higher (3,524 m, Leh-Ladakh) and lower (321 m, Chandigarh) altitudes. Results revealed significant physiological adaptations to high-altitude conditions, with increased concentrations of magnesium (748.84 {$\pm$} 4.06 mg/100 g), iron (189.83 {$\pm$} 2.16 mg/100 g), and manganese (8.48 {$\pm$} 0.27 mg/100 g), while potassium (3,400.83 {$\pm$} 3.82 mg/100 g), sodium (175.83 {$\pm$} 1.44 mg/100 g), and copper (1.69 {$\pm$} 0.01 mg/100 g) were higher at lower-altitude. Zinc content remained unchanged. Notably, dietary nitrate was higher (155.67 {$\pm$} 22.12 mg/100 g) at high-altitudes. Rhizospheric NFBs were isolated and functionally characterized for N2-fixation efficacy along with various plant growth-promoting (PGP) attributes; viz., production of ammonia, siderophores, HCN, IAA and phosphate solubilization. Field inoculation with selected strains significantly enhanced nitrogen content and plant growth. Soil chemical analysis further revealed significant differences between the altitudes. A total of twenty-seven NFBs belonging to Actinobacteria (77\%), Proteobacteria (11\%), Firmicutes(8\%), and Bacteroidetes(4\%) were isolated, with Streptomyces being the predominant genus, exhibiting distinct species at different altitudes. Remarkably, high-altitude strains showed significantly higher N2-fixing efficiencies (88.15 {$\pm$} 17.41 {\^A}?gN mL-1) than lower-altitude (65.7 {$\pm$} 14.36 {\^A}?gN mL-1) along with superior PGP traits. Overall, these findings suggest that E. sativa, enriched in key nutrients at high-altitudes, could be a valuable functional food crop, addressing the dietary needs of high-altitude populations. Furthermore, the rhizospheric NFBs identified in this study may be potentially beneficial for the development of novel bio-fertilizers, promoting eco-friendly agricultural practices through improved N2-fixation. Further field trials are recommended to validate their potential for sustainable crop production.}
}