Morphological and physiological responses of 1-year old Cupressus sempervirens to high carbon dioxide concentrations

Increasing use of fossil fuels has increased the atmospheric carbon dioxide concentrations. On the other hand, carbon dioxide is one of the most important factors for plant growth. Thus, the knowledge of plant response to these changes is very important. The aim of the present study was to evaluate the impact of increased carbon dioxide on some morphological and physiological traits of Cupressus sempervirens under greenhouse conditions. Levels of carbon dioxide concentrations included 450 (as control), 750 and 1100 ppm in a completely randomized design with three replicates was used. Three-year-old seedlings were treated for two months. The results showed that carbon dioxide concentration (750 ppm) increased the amount of proline to more than six times and in the concentration of 1100 ppm increased to more than twice compared to the control. Concentration of 750 ppm increased the amount of nitrogen and also had the greatest impact on the diameter of the collar. Similarly, the concentration of 1100 ppm increased significantly plant height and shoot fresh weight.