Hassan Masoumi - PhD of Crop Physiology. Uinversity of Payam-e-Noor; Tehran province. Minicity Blvd, Tehran, Iran,
Mahmoud Rreza Khorshidian - Department of Agriculture, Yekom Consulting Engineeres, ۱۳۳ Muzaffar Str. (North Saba), Vali Asr Square, Tehran ۱۴۱۶۷- ۹۳۱۹۷, Tehran, Iran

The salinity stress (100 ml mol sodium chloride) decreased the amount of net Co2 absorption and plant growth in both cultivars but in the same time when the two cultivars were selected against salinity and Co2, these parameters raised only in Koroneiki. Also, addition of Co2 (700 micro liter/liter) increased leaf area and dried weight of leaf and stem in Koroneiki, significantly. In this experiment, both cultivars showed that the same plant growth and water use efficiency but due to less concentration of sodium and chlorine ions in the root of Mission cultivars, this variety showed more tolerances to salinity stresses compared to Kronoeiky. Also, indicated that, those plants could grow under salinity stresses and high concentration of Co2, had the same growth parameters. This means that, before these parameters are affected by high concentrations of carbon dioxide, the parameters are affected by salinity.

Carbon dioxide concentration, Plant growth, Water use efficiency