Drought effects on growth, water status, proline content and antioxidant system in three Salvia nemorosa L. cultivars

چکیده مقاله

Plant growth and yield are infuenced by various environmental stresses, especially drought. An experiment was done to study the comparative efects of water stress on growth, physiology and antioxidant systems in three Salvia nemorosa L. cultivars (‘Isfahan’, ‘Violet Queen’ and ‘Rose Queen’). The cultivars were treated as control or water stress by stopping irrigation for 10 days. The results showed that the highest number of leaves per plant, leaf area, dry weight of root and shoot and total biomass were obtained from native cultivar ‘Isfahan’ under water shortage. Relative water content, chlorophyll a, b and total chlorophyll reduced in all studied cultivars under drought; but the rate of reduction was the lowest in ‘Isfahan’. Drought stress increased total soluble sugar in the root and leaf tissues in all cultivars and the highest values were obtained from native cultivar ‘Isfahan’. Drought stress also increased proline content, total phenols and favonoids in all tested cultivars; but the rate of increase in ‘Isfahan’ was higher than the other cultivars. The activities of catalase and peroxidase enzymes enhanced in all cultivars under drought stress conditions; however, their activities were higher in ‘Isfahan’ than the other cultivars. Among the cultivars studied, it was found that ‘Isfahan’ was more tolerant which was revealed by physiological and biochemical characteristics.