Effect of Different Irrigation Regimes on Physiological Characteristics, Yield and Water Productivity of Potato Genotypes in Ardabil

In order to detect the reaction of different potato genotypes to different irrigation regimes and evaluate their water productivity, a research was carried out as a split plot experiment based on a randomized complete block design with three replications in Agricultural Research Center and Natural Resources of Ardabil, Iran in 2015-2016. Five potato genotypes (Agria, Caesar, Savalan, 397081-1 and 397082-10) and three irrigation regimes (normal irrigation, 15 and 30 days without irrigation after 75 days of normal irrigation) were considered as treatments. The results showed that the effect of irrigation cuttings on the genotypes was significant for the mean fresh weight of tuber, number of tubers per plant, tuber yield per unit area, total dry matter yield and harvest index, marketable yield, dry matter percentage of tuber and water use efficiency. Under water stress conditions, water use efficiency was increased on the basis of tuber yield per unit area and marketable yield in genotypes 397081- 1, Agria and 397082-10. The highest water use efficiency was observed based on harvest index in Caesar and Agria genotypes (54.29 and 49.29 percent, respectively), and also based on the percentage of dry matter of tubers in genotypes 397081- 1, Caesar and Agria (6, 9 and 26 percent, respectively). When producing the highest tuber yield and water use efficiency under drought stress is aimed at planting genotypes 1-397081, agria and 397082-10 may bring about an effective use of water and show better growth and yield.