Storage of rainwater within the root depth zone is one of the modern ways to increase plant production. Subsurface water retention technology was applied to assess improving values of crop yield and crop water use efficiency, applying a membrane made of low-density polyethylene trough installed below the crop root zone. The goal of this paper is to assess that the retention of rainwater above the membrane can improve the crop yield and crop water use efficiency values for winter wheat. The experiment was conducted in open field, within Joeybeh Township, located in east of the Ramadi City, in Anbar Province, in winter growing season 2018-2019. Two plots T1 (with membrane trough) and T2 (without membrane) were used for the comparison and cultivated with winter wheat, where the rainwater was only the source of irrigation. At the end of the harvest stage the obtained results of crop yield and crop water use efficiency for plots T1 and T2 were; 0.35 kg/m2 and 1.66 kg/m3, and 0.28 kg/m2 and 1.28 kg/m3, respectively. The increasing value of crop yield and crop water use efficiency in plot T1 was about 25 % and 30 %, respectively more than plot T2. Benefits of the installation of membrane trough are to keep soil moisture for longer times, prevent the cracks of the soil surface and reduce the deep percolation losses.
