title: Plant growth promoting rhizobacteria Dietzia natronolimnaea modulates the expression of stress responsive genes providing protection of wheat from salinity stress.
abstract: Plant growth promoting rhizobacteria (PGPR) hold promising future for sustainable agriculture. Here, we demonstrate a carotenoid producing halotolerant PGPR Dietzia natronolimnaea STR1 protecting wheat plants from salt stress by modulating the transcriptional machinery responsible for salinity tolerance in plants. The expression studies confirmed the involvement of ABA-signalling cascade, as TaABARE and TaOPR1 were upregulated in PGPR inoculated plants leading to induction of TaMYB and TaWRKY expression followed by stimulation of expression of a plethora of stress related genes. Enhanced expression of TaST, a salt stress-induced gene, associated with promoting salinity tolerance was observed in PGPR inoculated plants in comparison to uninoculated control plants. Expression of SOS pathway related genes (SOS1 and SOS4) was modulated in PGPR-applied wheat shoots and root systems. Tissue-specific responses of ion transporters TaNHX1, TaHAK, and TaHKT1, were observed in PGPR-inoculated plants. The enhanced gene expression of various antioxidant enzymes such as APX, MnSOD, CAT, POD, GPX and GR and higher proline content in PGPR-inoculated wheat plants contributed to increased tolerance to salinity stress. Overall, these results indicate that halotolerant PGPR-mediated salinity tolerance is a complex phenomenon that involves modulation of ABA-signalling, SOS pathway, ion transporters and antioxidant machinery.
authors.affiliation: Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow- 226015, India.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Bharti
authors.affiliation: Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow- 226015, India.
authors.forename: Shiv Shanker
authors.initials: SS
authors.lastname: Pandey
authors.affiliation: Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow- 226015, India.
authors.forename: Deepti
authors.initials: D
authors.lastname: Barnawal
authors.affiliation: Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow- 226015, India.
authors.forename: Vikas Kumar
authors.initials: VK
authors.lastname: Patel
authors.affiliation: Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow- 226015, India.
authors.forename: Alok
authors.initials: A
authors.lastname: Kalra
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000192:Actinomycetales / Q000145:classification / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D053263:Gene Regulatory Networks; D009928:Organ Specificity; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D055051:Salt-Tolerant Plants / Q000235:genetics / Q000254:growth & development* / Q000382:microbiology; D015398:Signal Transduction; D012988:Soil Microbiology; D014908:Triticum / Q000235:genetics / Q000254:growth & development* / Q000382:microbiology
chemical_list: D010940:Plant Proteins; D000040:Abscisic Acid