Determination of the Potato Yield Response Factor (Ky) to Deficit Irrigation in Different Growth Stages in sharekord

This study was conducted to determine the yield response factor potato (ky) to deficit irrigation at different growth stages in a randomized complete block design with five treatment, E0 (Full Irrigation), E1 (85%), E2 (70%), E3 (55%) and E4 (30%) of actual evapotranspiration plant potato in three growth stages T1: seed and vegetative establishment, T2: the full development and T3: get the plant growing season in three years. the sharekord. Evapotranspiration potential of the potato crop was lysimeter drainage water balance method used to estimate the neutron meter. After harvest, yield and yield components were determined and potato yield response coefficient was calculated. The results of data analysis showed that deficit irrigation effects on potato yield is significant at the 5%. Maximum potato yield in full irrigation equal to 43416 kg up to 22150 kg in the lowest 70 percent evapotranspiration treatment - plant evapotranspiration in the third stage of plant growth.. evapotranspiration potential of the potato in the region with 944 mm and 542 mm minimum was E4T3 treatment. Coefficient responses yield of potato (Ky) with respect to the treatment of low irrigation for the first stage of growth between 0/65 to 1/18 and the second stage of growth between 0/82 and 1, and in the third stage of growth between 0/7 to 1/17 and the maximum growth season with 1/11 respectively.