Transcriptome Analysis Reveals Differences in Molecular Mechanisms Between Salt-Tolerant and Salt-Sensitive Rice...

To elucidate the molecular mechanisms underlying salt tolerance in rice (Oryza sativa L.), this study investigated differential transcriptional responses during the tillering stage. Salt-tolerant (N14) and salt-sensitive (N6) varieties were subjected to 0.3% and 0.6% NaCl treatments for 72 h, and their transcriptomes were analyzed via RNA-Seq. The results revealed distinct response strategies: 372 differentially expressed genes (DEGs) were identified in N14 and 393 in N6, with only 17 genes responding similarly. Gene Ontology (GO) analysis showed the tolerant N14 activated protein phosphorylation and lipid transport, primarily in the membrane and extracellular regions (e.g., ATP binding), whereas the sensitive N6 activated photosynthesis and protein folding, localized to chloroplasts and peroxisomes. KEGG analysis highlighted the activation of "Plant-pathogen interaction" in N14 versus "Metabolic pathways" in N6. Differential transcription factor activation was also observed, with N14 mobilizing 52 TFs (mainly WRKY and MYB) and N6 mobilizing 36 TFs (mainly MYB and b-ZIP). This study demonstrates that N14 and N6 utilize significantly different molecular pathways to cope with salinity, providing a crucial theoretical foundation for identifying novel salt tolerance genes and developing molecular breeding strategies.