Comparative transcriptome analysis between salt-tolerant and salt-sensitive naked barley landraces under salt stress at the germination stage.

Background: Salt stress is a major abiotic stress that threatens crop production globally. Among various growth stages, seed germination, crucial for seedling establishment and crop population, is highly sensitive to salt stress. Therefore, it is essential to explore the molecular mechanisms at this stage for the breeding of salt-tolerant crops and global food security.

Results: In this study, two salt-tolerant (B080 and B084) and two salt-sensitive (B004 and B005) naked barley landraces were exposed to salt stress for 7 days during germination and their transcriptome were compared to identify differentially expressed genes (DEGs) related to salt stress. In totally, 2348, 1847, 2251, and 1251 DEGs were obtained in B080, B084, B004, and B005, respectively. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment of DEGs were analyzed. Eight DEGs were further validated by qPCR. Although there were only two genes significantly differential expressed, the upregulation and downregulation trends of all genes were consistent with mRNA-seq data.

Conclusions: The analysis of DEGs between salt-tolerant and salt-sensitive naked barley landraces under salt stress, as well as their GO and KEGG enrichment, could reveal and enrich the molecular mechanism of salt tolerance in naked barley.