Effects of Ozonated Water Spraying on Physiological Characteristics and Gene Expression of Tartary Buckwheat

The leaves of Tartary buckwheat stress-tolerant variety Chuanqiao No.1 and stress-sensitive variety Chuanqiao No.2 were sprayed with 0.2, 0.4, 0.6 and 0.8 mg/kg ozonated water, and the physiological indexes such as fresh weight, chlorophyll and nitrogen content, plasma membrane permeability, and SOD activity of seedlings were measured. The results showed that spraying ozonated water with appropriate concentration was beneficial to improve the physiological characteristics and stress resistance of Tartary buckwheat. The appropriate concentrations of ozonated water for Chuanqiao No.1 and Chuanqiao No.2 were 0.6 mg/kg and 0.4 mg/kg. The expression of chlorophyll synthesis-related gene FtDCL, nitrogen transport-related gene FtAMT1-1 and stress resistance-related genes (FtSOD, FtNHX1, FtSOS1) in Tartary buckwheat could be significantly promoted by spraying ozonated water with appropriate concentration. The maximum expression level of FtDCL, FtSOD and FtSOS1 genes in Chuanqiao No.1 and Chuanqiao No.2 was at 12 h, while that of FtAMT1-1 and FtNHX1 genes in Chuanqiao No.2 was at 24 h and 6 h. The growth rate and stress resistance of Tartary buckwheat may be improved by ozonated water.