In this research we investigated the role of Si in improving salt tolerance in the medicinal plant Borago officinalis L. Borago was pretreated with 0, 0.5 and 1.5 mM Si (as sodium silicate, Na2(Si O2)3) and then treated with four levels of NaCl, namely, 0, 60, 90 and 120 mM NaCl. Then the effects of silicon and NaCl were observed on some physiological and biochemical parameters such as lipid ...