The Effect of Deficit Irrigation in Growth Stages on the aQuantity and Quality of Potatoes and Water Use Efficiency

This study was conducted to evaluate the impact of deficit irrigation and growth stages on yield and yield components of potatoes and water use efficiency. A field experiment was conducted at Shahrekord Agricultural Research Station over three years of crop seasons using a randomized complete block design with three replications. Plots were assigned to five levels of deficit irrigation treatments, E0 (full irrigation), E1 (85%), E2 (70%), E3 (55%) and E4 (30%) for actual evapotranspiration of potatoes, and three growth stages, T1, T2 and T3. Results of the combined analysis of variance showed that biological yield, tuber yield, yield components, water use efficiency and other traits in the growth stages were significantly affected by deficit irrigation treatments. Under E1, E2, E3 and E4 treatments, yield decreased by 5.1%, 8.9%, 13.12% and 25.5%, respectively, when compared to E0. Susceptibility at developmental stages of the potato to deficit irrigation differed. The T1 stage was the most critical stage under water stress conditions. Water use decreased compared to E0 by 17.5% in stage T1, 11.1% in stage T3 and 10.08% in stage T2.