Abstract
Soybean (Glycine max L.), belonging to Leguminosae, is an essential food in Asian countries. It has become a necessity to study the long-term effects of elevated concentrations of CO2 on plant growth and development. Climate change may be affected by the increment of CO2 and higher temperatures on crops. Elevated concentrations of atmospheric CO2 can negatively affect the yield as well as the quality of the field crops. Alpha-tocopherol is the major vitamin E compound found in leaf chloroplasts. This antioxidant deactivates photosynthesis-derived reactive oxygen species and prevents the propagation of lipid peroxidation by scavenging lipid peroxyl radicals in thylakoid membranes. AL-Hunay is an electrical power plant main station located in the Al-Hofuf agricultural area in Saudi Arabia. The role of alpha-Tocopherol in mitigating the effect of CO2 emitted from AL-Hunay on the morphological and physiological traits of soybean has been investigated in this study by selecting a site of 100 meters apart from the station. The results revealed a negative effect of elevated concentrations of CO2 on the morphological traits of soybean such as plant height, leaf area, and number of leaves. Furthermore, it also negatively affected the physiological traits such as the contents of P and K, mono- and disaccharides, chlorophyll a and b and the activity of catalase, and superoxide dismutase. The results showed an obvious role of alpha-Tocopherol in mitigating the effect of elevated CO2 on soybean plants through regulating the growth, stimulating photosynthesis, protecting the cell membrane and chloroplasts, and tolerating oxidative stress. The current study provides proof for the positive role of alpha-Tocopherol in mitigating the effect of elevated CO2 emitted by the AL-Hunay power plant main station on the morphological and physiological traits of Glycine max L. plants.