Exogenous nitric oxide on morphological, biochemical and antioxidant enzyme activity on savory (Satureja Hortensis L.) plants under cadmium stress

Abstract

Abstract Cadmium (Cd) is a heavy metal which causes environmental pollution and affects physiological and morphological characters of plants. Sodium nitroprusside is generally used as Nitric Oxide (NO) donor in plants. A glasshouse pot experiment was carried out to investigate the effect of exogenous NO on physiological, biochemical and enzyme activity of savory plants under Cd stress. Experimental factors included soil contamination with cadmium chloride (0 control, 75, 100 and 150 µM) and NO foliar application in four concentrations (0 control, 50, 100 and 200 µM). The results showed that Cd stress decreased growth parameters including plant height, number of leaves and lateral branch, 25.97%, 19.18% and 22.39%, respectively. In contrast, proline accumulation, membrane cell leakage, carbohydrates and antioxidant enzymes activity were increased. While NO application improved savory plant growth under Cd stress. NO application improved growth of plants under all Cd concentration for example under highest Cd concentration (150 μM) foliar application of 200 μM NO, proline, chlorophyll (a , b and carotenoid), carbohydrates and peroxidase activity were 116.48%, 56.25%, 38.38%, 48%, 140% and 85.78% compared to relative control increased, respectively. Also, NO application (200 µM) reduced the Cd accumulation in the shoot and roots of plants.