Evaluation of resistance to drought stress in seedlings of two lines of Triticale (Triticosecale × Wittmack) with emphasis on some enzymatic and non-enzymatic antioxidants

Drought is one of the most important factors that limit plant growth and development. In order to study the effect of drought stress in two lines of Triticale Sanabad and ET83-20 as the new man-made cereal, a greenhouse experiment was arranged in a three-replicate completely randomized factorial design. Drought stress was applied as limited irrigation by 30% and 60% of field capacity as a drought condition and 90% of field capacity as a control. One week after applying the stress, some growth criterions and biochemical parameters were evaluated for seedlings. Results of statistical analysis showed that drought stress reduced growth parameters (including dry weight of root and shoot, root length and diameter, root and leaf area) and increased the levels of chlorophyll a, b, total chlorophyll and carotenoid in both lines. However, the pigments contentof ET83-20 had a further increase than the other. The results also showed that proline content as non-enzymatic antioxidant and soluble sugars as osmolytes and antioxidant enzyme activities of superoxide dismutase and guaiacol peroxidase increased under drought stress. However, these increases were more significant in line Sanabad. The damage levels of growth criterions and defence mechanisms show that ET83-20 is less resistance to drought stress than Sanabad. So the line Sanabad could be introduced as a better alternative to wheat bread.