Effects of Cement Dust on the Physiological Activities of Arabidopsis thaliana

Abstract

Air pollution exerts detrimental effects on plant ecosystems and restricts agricultural productivity. Cement dust is considered to be one of the most harmful air pollutants of industrial origin and is a limiting factor for plant growth and productivity. This study aims to uncover the impacts of cement dust on photosynthetic pigments, protein content, hydrogen peroxide (H₂O₂) accumulation, lipid per oxidation and antioxidant enzyme activities of Arabidopsis thaliana. In this study, Arabidopsis plants were dusted with cement at a rate of 1.5 g per 1-m² area and measurements were undertaken at 10 days after cement dust application. Treatment with cement dust resulted insignificant reductions in chlorophyll content and total soluble protein accumulation. Neither carotenoid nor starch content of Arabidopsis plants was affected by exposure to cement dust, whereas protease activity was significantly enhanced in cement dust-treated plants. Furthermore, exposure to cement dust significantly enhanced the production of H₂O₂, a product of oxidative stress, in the leaves of Arabidopsis plants. Moreover, Malondialdehyde (MDA) content, a product of lipid per oxidation, significantly increased after exposure to cement dust. In response to cement dust, activities of scavenging enzymes such as Ascorbate Peroxides (APX), Superoxide Dismutase (SOD) and Guaiacol Peroxidase (GPX) increased, whereas the activity of Catalase (CAT) activity decreased. The present results suggest that cement dust induced oxidative stress in Arabidopsis plants through the generation of Reactive Oxygen Species (ROS), induction of lipid peroxidation and up regulation of antioxidant enzyme activities.