Transcriptome profiling reveals key genes in eggplant (Solanum melongena) roots under salt stress

Roots are the initial organs that perceive and adaptively adjust when exposed to salt stress. However, the mechanisms underlying salt stress tolerance in eggplant (Solanum melongena) roots remain elusive. In this study, salt stress markedly elevated the Na⁺ ion concentration, reactive oxygen species (ROS), proline, and malondialdehyde (MDA) content, in addition to enhancing the activities of superoxide dismutase (SOD) and peroxidase (POD) in the roots of the eggplant inbred ZH171. Transcriptome analysis revealed a total of 3491 DEGs in eggplant roots response to salt stress. Most of the DEGs under salt stress were mainly involved in oxidoreductase activity, hydrolase activity, pentose and glucuronate interconversion, microtubule motor activity, ion transport, hydrolytic activity. Some genes were enriched in peroxidase activity, indicating the activation of the antioxidant enzyme system in alleviating oxidative damage under salt stress. A total of 236 DEGs mainly within ERF, MYB, NAC, bHLH, and WRKY TF families, and the most upregulated genes from NAC. Taken together, this study provides important candidate genes linked to salt tolerance in eggplant roots, offering a foundation for further in-depth study of resistance mechanisms in eggplant ZH171.