Irrigation water use efficiencies (IWUE) of treatments were increased with decreasing plant water consumption in both years. The highest water use efficiencies (WUE) of the first and second years were determined in I55 and I70 treatments, respectively. Therefore, the irrigation level obtained of the highest yield per unit water in areas where water is scarce can be suggested for water-saving.
Yield response factors (Ky) of treatments in the first and the second years were determined as 0.59 and 0.99, respectively ( Fig. 7). This situation indicates that second year might be decrease 0.99 unit yield per one unit of water deficiency. The amount of irrigation water, plant water consumption and Ky values in the second year increased significantly due to higher climate parameters (evaporation, temperature, etc.) in the second year than the first year. Yildirim and Kodal (1998) determined that yield response factor (Ky) for total growing period were found as 0.96.