Effect of cold application on the expression of genes responsible for glycoside amount and biosynthesis in Stevia plant

Stevia rebaudiana Bertoni, one of the most important sources of calorie-free and natural sweeteners that are becoming increasingly widespread in the world and in money, consists of different sweet sources called steviol glycosides. The meaning of the expression of genes affecting the amount and biosynthesis of glycosides in plants. Transcriptome profiles were examined and the expression levels of the genes recorded for the study (UGT76G1, UGT74G1, ent-KAH, GGGPS, HDR, AACT, ACTIN, UBQ) were determined by real-time PCR under stress conditions. While the expression levels of the GGPPS,AACT gene increased under +4°C cold stress; A decrease in HDR, entKAH, UGT76G1, UGT74G1 gene levels was observed. In other words, while the MVA pathway was activated in synthesis, the expression of genes in the MEB pathway decreased. HPLC analysis was performed on dry leaf samples taken from the plants of the study. Reb A, Steviside, Reb C, Dulcosite amounts. Significant differences were detected between application temperatures of +4 °C and +24 °C. Molecular studies reveal the characteristics of the components of changes in the expression of genes affecting glycoside biosynthesis. This study will contribute to the breeding of a new species, resistant to cold stress, for the acclimatization of the stevia plant with coastal connections in more temperate climates, depending on the light intensity.