بررسی اثر سیلیکون بر آنزیمهای ضداکسنده در گیاه جو تحت تنش خشکی

Drought stress is one of the largest abiotic stresses worldwide. Silicon is the second most abundant element in soils that have beneficial effects on biotic and abiotic stress tolerance in plants. Effect of external silicon in increasing plant resistance to various stresses such as drought, salinity, metal toxicity and UV radiation has been demonstrated. The purpose of this study is to investigate the effect of silicon on yield of two antioxidant enzymes named superoxide dismutase (SOD) and peroxidase (POX) in two barley cultivars, Nimruz (resistance) and Gorgan (sensitive), under drought stress. This experiment is performed in a randomized factorial design with three treatments (control, drought, and silicon-drought) with three replications in four leaves stage of barley (Hordeum vulgar L.) by spectrophotometry and native gel methods. The results showed that treatment of silicon increase the activity of these two enzymes especially superoxide dismutase enzyme. However, the increase in resistant cultivars was more than sensitive cultivar. These results represent a reduction of oxidative damage induced by drought stress by increasing antioxidant enzymes in presence of silicon on barley plant.