Transcriptome Analysis of Salt Stress Response in the Root System of Periploca sepium at Different Time Points

Illuminate the genome-wide dynamic response to salt stress in Periploca sepium Bunge and the mining of the key salt-tolerant genes. After 30 days of growth and treatment with 1% NaCl, transcriptome sequencing was performed and select genes were tested for RT-qPCR to ensure transcriptome accuracy. The results showed that there were 2225, 2579, 3852 and 3811 differentially expressed genes (DEGs) under salt stress for 4 h, 12 h, 24 h and 48 h, respectively. In the early stage, the redox balance in P. sepium was broken, and with the increase of ROS, the expression of antioxidant enzymes was also increased, and plant growth was inhibited, which was manifested in the significantly down-regulated expression of GA synthesis genes. With the increase of salt stress time, the process of energy metabolism and resource recombination in P. sepium was strengthened, and protein degradation and synthesis occurred accordingly. After 2 days of response adjustment, the differential genes in plants gradually stabilized, and the expression of genes related to reducing substances such as flavonoids was significantly up-regulated, and the plants re-established a stable state to adapt to the new environment.