The Study of interaction between Silicon and Salinity on some Physiological and Anatomical Parameters of borage (Borago officinalis L.)

Nowadays medicinal plants are considered as important economical plants. Recently, due to the extension of saline lands, shortage of appropriate agricultural farms and economical value of medicinal plants. There is a growing interes of identifying salt tolerant medicinal plants. A cheap time saving and reliable way for selecting proper salt tolerant plants can be achieved by culturing these plants in hydroponic condition. On the other hand, silicon which is the second most abundant element of soil has good effects on increasing the plant's ability in enduring biotic and abiotic stresses. This experiment was arranged as a factorial scheme based on randomized complete block design with four replications. Six levels of silicon (0, 0.5, 1, 1.5, 2, 2.5 mM) and two levels of NaCl (0 and 120 mM) were added to nutrient solution in order to analyze the reaction of salt and silicon on physiological and anatomical properties of Borago officinalis L. In this study, the effects of salinity and silicon on shoot apical meristem and contents of chlorophyll, carotenoids, antocyanin, phenols and reducing sugars were assessed. The results showed that salinity decreased the chlorophyll, carotenoids, phenols and reducing sugars but increases the anthocyanin content. Although in comparison with the plants which was just treated by salt, silicon treatment, especially with 1.5 mM, made an improvement in the studied physiological and biochemical parameters. Also silicon could moderate negative effects of salt treatment on shoot apical meristem.