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Abstract Background Plant growth promoting rhizobacteria (PGPR) , such as Bradyrhizobium japonicum IRAT FA3, are able to improve seed germination and plant growth under various biotic and abiotic stress conditions, including high salinity stress. PGPR can affect plants’ responses to stress via multiple pathways which are often interconnected but were previously thought to be distinct. Although the overall impacts of PGPR on plant growth and stress tolerance have been well documented, the underlying mechanisms are not fully elucidated. This work contributes to understanding how PGPR promote abiotic stress by revealing major plant pathways triggered by B. japonicum under salt stress. Results The plant growth-promoting rhizobacterial (PGPR) strain Bradyrhizobium japonicum IRAT FA3 reduced the levels of sodium in Arabidopsis thaliana by 37.7% . B. japonicum primed plants as it stimulated an increase in jasmonates (JA) and modulated hydrogen peroxide production shortly after inoculation. B. japonicum -primed plants displayed enhanced shoot biomass, reduced lipid peroxidation and limited sodium accumulation under salt stress conditions. Q(RT)-PCR analysis of JA and abiotic stress-related gene expression in Arabidopsis plants pretreated with B. japonicum and followed by six hours of salt stress revealed differential gene expression compared to non-inoculated plants. Response to Desiccation ( RD ) gene RD20 and reactive oxygen species scavenging genes CAT3 and MDAR2 were up-regulated in shoots while CAT3 and RD22 were increased in roots by B. japonicum , suggesting roles for these genes in B. japonicum -mediated salt tolerance. B. japonicum also influenced reductions of RD22 , MSD1 , DHAR and MYC2 in shoots and DHAR , ADC2 , RD20 , RD29B , GTR1 , ANAC055 , VSP1 and VSP2 gene expression in roots under salt stress. Conclusion Our data showed that MYC2 and JAR1 are required for B. japonicum -induced shoot growth in both salt stressed and non-stressed plants. The observed microbially influenced reactions to salinity stress in inoculated plants underscore the complexity of the B. japonicum jasmonic acid-mediated plant response salt tolerance.
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This content will become publicly available on December 1, 2026
Biochemical changes and phytoextraction potential of quinoa and wheat for their resilience to salt stress
Phytoextraction presents a promising alternative for desalinating saline environments. Our study investigated the phytoremediation efficiency and ion uptake mechanisms of Chenopodium quinoa (Quinoa) and Triticum aestivum (wheat) in response to salt stress. The plants were subjected to NaCl-induced salinity levels of 5, 10, and 15 dS m⁻1 in a hydroponic system, and we measured the remediation efficiency for sodium, potassium, calcium, magnesium, and chloride ions. The solutions incubated with wheat plants exhibited higher ion concentrations than those with quinoa. Chenopodium showed significantly higher bioaccumulation of ions (Mg2⁺, Ca2⁺, Na⁺, Cl⁻, K⁺) in its roots and leaves compared to Triticum. Chenopodium demonstrated greater ion uptake efficiency than Triticum. Under control conditions, both plants effectively contributed to desalination, as indicated by their translocation factor values. In contrast, Chenopodium showed higher TF under salt stress than Triticum for the measured ions. Salinity did not significantly affect potassium accumulation in quinoa shoots, which helped maintain membrane integrity compared to wheat. The analysis of the oxidative status revealed that wheat accumulated higher levels of hydrogen peroxide and lipid peroxidation, especially in the roots. The activities of antioxidative enzymes superoxide dismutase, peroxidase, catalase, ascorbic peroxidase, and glutathione reductase showed a significant increase in the roots and leaves of Chenopodium under salt stress, providing essential protection against reactive oxygen species and lipid peroxidation. Additionally, the increase in leaf area and dry weight in quinoa indicates a more significant accumulation of ions at higher concentrations, demonstrating its superior phytoremediation efficiency compared to wheat
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- Award ID(s):
- 2150087
- PAR ID:
- 10655125
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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