Differential oxidative stress responses in Brassica juncea (L.) Czern and Coss cultivars induced by cadmium at germination and early seedling stage

Abstract

Heavy metal contamination is a major trouble across the world. In India, there have been many reports of heavy metal pollution due to speedy industrialization and urbanization. The Indian brown mustard is an important oil yielding crop. However, the response of Indian mustard at germination and early seedlings stages to heavy metals like cadmium (Cd) stress is not clear. Current work renders a perceptivity into the part played by enzymatic and non-enzymatic antioxidants towards differential response of Cd (0, 0.5, and 1.0 mM doses) stress in mustard cultivars (Pusa bold, Pusa bahar, and Pusa agrani). The results show that irrespective of dose, Cd severely hamper germination and retard the early seedling growth in mustard cultivars. Pusa bold showed comparatively less reduction in seedling growth as compared to Pusa bahar and Pusa argani. Oxidative stress as measured by lipid peroxidation (MDA), hydrogen peroxide (H2O2), lipoxygenase (LOX), and cell death was significantly less in Pusa bold than Pusa agrani. Chlorophyll and carotenoids’ content was significantly reduced in Pusa agrani compared to Pusa bold. On the other hand, antioxidant metabolites (proline, ascorbate, and glutathione) showed increased accumulation under Cd stress in Indian mustard; also was the case with antioxidant enzymes (superoxide dismutase, catalase, glutathione-s-transferase, glutathione reductase, ascorbate peroxidase, and peroxidase), which significantly (p Pusa bahar > Pusa bold