| Summary: | Background: GRAS transcription factors are crucial for plant development and stress responses but remain poorly characterized in citrus. Soil salinization increasingly threatens sweet orange (<i>Citrus sinensis</i>) yield. Identifying salt-responsive <i>GRAS</i> genes could reveal key tolerance determinants for breeding resistant cultivars. Methods: We systematically identified and analyzed sweet orange GRAS transcription factors using bioinformatics. Results: Forty-three <i>CsGRAS</i> genes were identified, phylogenetically classified into ten subfamilies, and found to be structurally conserved. A promoter analysis revealed a high prevalence (58.78%) of hormone- and stress-responsive cis-elements. These genes reside on nine chromosomes, with segmental duplication being the primary evolutionary driver (eight duplicated pairs). Functional enrichment implicated hormone signaling pathways in regulating growth under stress. Transcriptome profiling identified 42 differentially expressed <i>CsGRAS</i> genes (19 upregulated and 23 downregulated) under salt stress. qRT-PCR validated the expression patterns of selected genes (e.g., <i>CsGRAS15</i> and <i>CsGRAS27</i>). Notably, DELLA subfamily members <i>CsGRAS15</i> and <i>CsGRAS27</i>, key negative regulators in gibberellin (GA) signaling, were differentially expressed. Modulating these DELLA proteins presents a promising strategy to enhance sweet orange salt tolerance by mitigating GA-mediated growth inhibition during stress. Conclusion: This study identifies salt-responsive <i>CsGRAS</i> genes, highlighting <i>CsGRAS15</i> and <i>CsGRAS27</i> as potential targets for improving salt tolerance in citrus.
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