Investigation of different selenium sources on phytochemical characteristics of Echium amoenum fisch. & C.A. Mey. as a medicinal herb of Iran

The aim of this research was to determine the effect of selenium forms (sodium selenate and sodium selenite) at (2, 4, 8 and 16 mg/l) level on the phytochemical attributes of Echium amoenum (Vipers bugloss) as factorial randomized complete block design. Selenium sources were added in four steps: 2 true leaves stage, 10 leaves, 2 weeks and 1 week before flowering. The traits were evaluated in different stages of flowering (beginning, full flowering, and end of flowering). Results showed that selenium sources significantly affected the qualitative characteristics of the E. amoenum. The highest photosynthetic pigments were obtained by 4 mg/l sodium selenite at beginning of flowering. When the plants were sprayed with 4 mg/l sodium selenate and harvested at beginning of flowering, higher total alkaloid contents in leaves and petals were observed compared to the other treatments. When the plants were sprayed with 8 mg/l sodium selenate and harvested at end of flowering, higher total phenols and flavonoids contents, soluble sugars content was observed compared to the other treatments. Moreover, foliar application of selenium sources significantly increased the content of this element in the petals. Sodium selenate was more effective than sodium selenite in increasing the content of this element. Generally, the results showed selenium sources significantly improved phytochemical properties of E. amoenum.