The effect of Silicon treatment on improving the physiological response of Radish (Raphanus sativus L.,) to salinity stress

Abstract The increasing population and high demand for cultivation of crops in the area with high salt concentration promoted the application of new strategies to improve plant tolerance to salinity stress. The present study was conducted to investigate the effect of potassium silicate (۰, ۱۰ and ۲۰ mM) on reducing the harmful effect of salinity stress induced by sodium chloride (۰, ۱۰۰ and ۲۰۰ mM) in radish. The experiment was performed as a pot experiment using a Randomized Complete Block Design with four replications. Salinity stress significantly reduced the chlorophylls content, chlorophyll fluorescence (Fv/Fm and PIABS), carbohydrates, proteins and plant biomass, while silicon treatment reduced the adverse effect of salinity stress on them. In response to salinity stress, proline, the activity of superoxide dismutase, H۲O۲ accumulation and membrane lipids peroxidation showed a significant increase, while the amounts of phenols, anthocyanins and FRAP antioxidant capacity of plants decreased. Silicon treatment increased phenols, anthocyanins and FRAP antioxidant capacity of salt stressed-plants, which was accompained with the reduction of H۲O۲ accumulation and subsequently reduction of membrane lipids peroxidation. Based on the results of present study, it can be suggested that silicon treatment reduced the adverse effect of salinity on the growth and yield of radish plant through the improvement in chlorophylls content and fluorescence, reduction of reactive oxygen species, and increasing the antioxidants and osmotic compatible solutes.

کلیدواژه ها:

Antioxidants ، Compatible solutes ، Growth ، Photosynthetic parameters ، Sodium Chloride. ، آنتی اکسیدانت ها ، رشد ، شاخص های فتوسنتز ، کلرید سدیم ، محلول های سازگار اسمزی