Effect of aspartic acid on physiological characteristics and gene expression of Tartary buckwheat

Abstract The salt-tolerant variety Chuanqiao No.1 of Tartary buckwheat was used as the experimental material. 10, 20, 30, 40, 50 and 60 µM aspartic acid treatment was used to determine the germination rate of Tartary buckwheat seeds and growth indexes such as seedling root length, stem diameter, plant height, fresh weight, chlorophyll content and nitrogen content. The expression levels of growth related genes were also measured after treatment with appropriate concentrations of aspartic acid to study the effects of aspartic acid on seed germination and seedling growth of Tartary buckwheat. The results showed that aspartic acid treatment could significantly increase the germination rate of Tartary buckwheat seeds, and 40 µM of aspartic acid was the appropriate concentration to promote seed germination. Spraying appropriate concentration of aspartic acid could increase the root length, stem thickness, plant height, fresh weight, chlorophyll and nitrogen content of Tartary buckwheat seedlings. The appropriate concentration for aspartic acid spraying is 30 µM. After spraying appropriate concentration of aspartic acid, the expression levels of chlorophyll synthesis related genes (FtDCL and FtGLK1) and nitrogen transport related genes (FtAMT1-1 and FtNRT2.3) in Tartary buckwheat significantly increased from 6 h to 24 h, and both reached their maximum expression levels at 6 h of treatment. It indicated that aspartic acid has a promoting effect on seed germination and seedling growth of Tartary buckwheat, which is beneficial for plant growth.