Effects of Water Retaining Agent on Yield and Water Use Efficiency of Potato in Semi-arid Area

The effects of water retaining agent and water supplement on potato yield and water use efficiency(WUE)in semi-arid area was conducted.The results showed that water consumption of potato during the growing season concentrated in the 80 cm soil depth mainly.The change of water content below 80 cm layer was not significant and was almost not absorbed by potato basically.Under the condition of water retaining agent treatment,water use efficiency(WUE) at population and yield level of potato were the highest,42.73 and 94.21 kg(mm·hm2),respectively,and the yield were also the highest,however,WUE at leaf level was the lowest.