Evaluation of the distribution of cadmium and its toxic effects on the biological responses of Nicotiana tabacum L.

Abstract

The tobacco plant (Nicotiana tabacum L.) is introduced as a template in botanical research. The environmental pollutant cadmium (Cd) contributes to cell destruction by elevated reactive oxygen species (ROS). In this study, to clarify the response of tobacco plants to Cd-induced oxidative stress, the effects of cadmium chloride (CdCl2) at five levels (0, 1, 1.5, 2, and 2.5 mM) were researched on morphological and biochemical characteristics. The finding revealed that the increased concentration of CdCl2 reduced the values ​​of PLSTI (plantlet length stress tolerance index), PDSTI (plantlet dry weight stress tolerance index), and relative water content. CdCl2 significantly increased proline, antioxidant capacity, MDA (Malondialdehyde), and H2O2 levels. As the concentration of cadmium in the environment elevates, its accumulation in roots and shoots increases. However, the amount of Cd accumulated in the roots was greater than in the shoots. The high potential of tobacco to absorb heavy metals introduces this plant as a suitable Cd accumulator, while, due to the non-edible consumption of tobacco, it can also be used in phytoremediation. This study helps to better understand the interaction of different antioxidant pathways with Cd toxicity as well as the biochemical changes resulting from oxidative stress pathways in tobacco plants.

Keywords

• Antioxidant enzymes
• Cadmium chloride
• Oxidative stress
• tobacco