Identification of Reliable Reference Genes for Gene Expression Analysis in Saposhnikovia divaricata (Turcz.) Schischk under Salt and Drought Stress

The Quantitative Real-time PCR (qRT-PCR) technique enables exact estimate of target gene expression, careful selection of appropriate reference genes is required. In this study, we evaluated eight candidate reference genes (GAPDH-1, GAPDH-2, EF1A-1, EF1A-2, 18SrRNA-1, 18SrRNA-2, 18SrRNA-3, UBQ) using root tissues from Saposhnikovia divaricata (Turcz.) Schischk under two different abiotic stress conditions. Quantification of expression levels was carried through qRT-PCR analysis and stability was assessed using geNorm, NormFinder and BestKeeper algorithms as well as RefFinder software. Validation was performed by analyzing ABF gene expression. Our findings showed that the expression stability of GAPDH-2 was the highest, while 18SrRNA-3 was the lowest. This study provides valuable insights for standardized selection of reference genes and accurate transcript quantification in SD gene expression and functional analysis.