Effects of Elevated Carbon Dioxide and Deficit Irrigation Regimes on Morphological and Physiological Characteristics of Lentil (Variety Kimia)

Studies have shown that the global climate has been dramatically changed during last decades. The results of the investigations have shown that enhancement of greenhouse gases due to human activities is one of the main factors of climate change in the present century. CO2 is one of the most important greenhouse gases, which has begun to increase rapidly since the mid-19th century. Studies have shown that carbon dioxide concentrations have risen by about 43% from 277-280 ppm since the late 1700s and now the concentration of this gas is close to 400 ppm (Samenow, 2013). According to scientists, carbon dioxide is responsible for 61% of the total global warming.
In addition to the harmful effects of increasing the carbon dioxide concentration and global warming, this gas has a positive effect on agriculture, which increases its importance. The results of the research indicate that increasing CO2 concentration causes photosynthesis enhancement also by increasing the photosynthesis dry matter weight increase, and consequently the amount of production increases (Semenow et al., 2012‎).
Rogers et al., (1994), indicated that doubling carbon dioxide concentration has led to an increase in plants’ yield approximately by 33%. In addition, environmental conditions such as light, temperature, water and available nutrients, moisture, etc., and the interaction between them, overwhelms the effect of plants on changes in carbon dioxide concentration.