Effect of UVA+B on Germination Consequences, Oxidative Stress and Antioxidant Defence Mechanisms of Wheat Triticum aestivum L.

Stratospheric ozone depletion will increase the solar ultraviolet radiations especially in the range UV-A and UVB. Increased levels of UV radiations affect and cause damage on cellular level on various organisms. Current research study was targeted to evaluate the effect of seed pretreatment with ultraviolet radiation on germination, oxidative damage and some antioxidant enzymes of three common wheat (Triticum aestivum L.) cultivars namely; Sakha-94, Gemmiza-9 and Giza-168. Seeds were irradiated to ultraviolet radiation with wavelength from 300-410 nm and maximum wavelengths of 350 nm for 6 different exposure doses (1, 5, 10, 30, 60 and 120 s). Various germination indices, oxidative stress and protective enzymes were estimated and recorded every two weeks till harvest of experiment. Ultraviolet radiation induced increases in germination consequences of wheat cultivars especially seed germination percentage and germination rate. Seed pretreatment with ultraviolet radiations induced a significant decrease on various oxidative stress damage consequences both hydrogen peroxide level and lipid peroxidation, which were monitored biweekly till harvest. Antioxidant enzymes estimated; superoxide dismutase, catalase and ascorbic acid peroxidase showed a huge and significant activation after seed pretreatment with different doses of UV-light. Data provide a new trend in priming using ultraviolet radiations of wavelengths range UV-A and UV-B