BACKGROUND: Abiotic stress can damage crops and reduce productivity. Among them, salt stress is related to water stress such as osmosis and ions, and like other abiotic stresses, it can affect the growth of plants by changing gene expressions. Investigating the profiles of gene expression under salt stress may help us understand molecular mechanisms of plants to cope with unfavorable conditions.RESULTS: To study salt tolerance in sorghum, physiological and comparative transcriptomic studies were performed using a Korean sorghum cultivar 'Sodamchal' which is considered sensitive to soil salinity. In this study, the samples were treated with two concentrations of NaCl [0 (control) and 150 mM], and the leaves and roots were harvested at 0, 3, and 9 days after the treatment. For the physiological study, the levels of anthocyanin, proline, reducing sugar, and chlorophyll were evaluated in the control and the treatment group at each sampling point. The results show that the cultivar 'Sodamchal' has salt-susceptible profiles. We also analyzed the transcription profile in the presence of 0 and 150 mM NaCl to confirm the candidate genes under the saline stress condition. Between the control and salt treatment, we found a total of 1506 and 1510 differentially expressed genes (DEGs) in the leaves and roots, respectively. We also built a gene co-expression network to determine the association of the candidate genes in terms of biological pathways.CONCLUSIONS: Through the co-expression network, genes related to salt stress such as AP2/ERF and Dehydrin were identified. This study provides the physiological and genic markers that could be used during intense salt stress in sorghum. These markers could be used to lay the foundation for the distribution of high-quality seeds that are tolerant to salt in the future.

Physiological and Transcriptomic changes under Salt Stress in ‘Sodamchal’, a Korean Line of Sorghum

Chungnam National University 2020-0536-01