The influence of Thidiazuron (TDZ) and Silver Thiosulfate (STS) on morphological and phytochemical characteristics under in-vitro condition in evening primrose

Evening primrose (Oenothera spp) is an ornamental plant from Onagraceae family. Next to the ornamental, it has also medicinal properties. Secondary metabolites, including phenolic compounds, are important in this plant. So that leaves evening Primrose had numerous phenolic compounds and antioxidant properties. Adding some of the compounds to the culture medium increases the production of secondary metabolites, including Thidiazuron (TDZ) with cytokine activity and Silver Thiosulfate (STS) with strong ethylene and antibacterial properties. In this experiment the effect of TDZ treatments and STS in five levels (0, 5, 10, 15 and 20 µm) on morphological and phytochemical characteristics (chlorophylls and carotenoids, flavonoids, phenols and anthocyanins) were measured. The results showed that TDZ treatment was significant on morphological traits such as number of leaves, plant, stem and root weight, stem size, total dry weight, leaf and stem dry weight at 1% level. Also, different concentrations of STS treatment also had a significant effect on some parameters such as root weight, stem size, leaf area and width and length of leaf, stem dry weight and root dry weight at 1% level. The results shown that, TDZ and STS had greatest effect was on the amount of phenol and chlorophyll a content, which was also significant at 1% level. According to the results, TDZ 20 µm had the greatest amount of phenol (14.93 µg/gFW). The results showed that with increasing concentration TDZ, the amount of phenols increased and it enhance antioxidant properties. Also, the highest chlorophyll a was observed in 20 µm STS (10.43 mg/gFW). Finaly, the results shown that TDZ and STS treatments had good effect on increasing total phenol.