Effects of CO₂ concentration on photosynthetic characteristics and physiological and biochemical indices of cowpea

The effects of CO2 concentrations on photosynthetic characteristic and biochemical indices at the dwarf cowpea seedlings were studied in the South Greenhouse. The results show that, under different CO2 concentrations, the photosynthetic pigment content, soluble sugar content and soluble protein content increased to a different extent with the increase of CO2 concentrations. High CO2 concentrations could prominently increase the photosynthetic rate of cowpea, while decrease the transpiration rate compared with the control. SOD, POD, and CAT varied remarkably under different CO2 concentrations. The maximum enzyme activities were observed at CO2 concentration 1200 mL/m3. The MDA content decreased significantly in cowpea leaves at the higher concentrations of CO2.