TY - JOUR N2 - In many regions of the world, including Egypt, water shortages threaten food production. An irrigation deficient strategy in dry areas has been widely investigated as a valuable and sustainable approach to production. In this study, the dry matter and grain yield of wheat was decreased by reducing the amount of irrigation water as well as the volume of the root system. As a result of this, there was an increase the soil moisture stress. This negatively affected the absorption of water and nutrients in the root zone of wheat plants, which ultimately had an effect on the dry matter and grain yield of wheat. The values of dry matter and grain yield of wheat increased with the ʻSakha 94ʼ variety compared to the ʻSakha 93ʼ class. It is possible that this was due to the increase in the genetic characteristic of the root size with the ʻSakha 94ʼ variety compared to the ʻSakha 93ʼ class, as this increase led to the absorption of water and nutrients from a larger volume of root spread. Despite being able to increase the water productivity of wheat by decreasing the amount of added irrigation water, the two highest grain yield values were achieved when adding 100% and 80% of irrigation requirements ( IR) needed to irrigate the wheat and no signif-icant differences between the yield values at 100% and 80% of IR were found. Therefore, in accordance with this study, the recommended irrigation for wheat is at 80% IR which will provide 20% IR. When comparing the water productivity of two wheat varieties in study, it becomes clear that ʻSakha 94ʼ was superior to ʻSakha 93ʼ when adding the same amount of irrigation water, and this resulted in increased wheat productivity for ʻSakha 94ʼ. The SALTMED results confirmed good accuracy (R2: 0.92 to 0.98) in simulating soil moisture, roots volume, water application efficiency, dry matter, and grain yield for two varieties of wheat under deficit irrigation conditions. Whilst using sprinkler irrigation system under sandy soils in Egypt. L1 - http://www.journals.pan.pl/Content/119859/15%20Abdelraouf%20et%20al%20789.pdf L2 - http://www.journals.pan.pl/Content/119859 PY - 2021 IS - No 49 EP - 138 DO - 10.24425/jwld.2021.137105 KW - irrigation KW - roots volume KW - SALTMED model KW - soil moisture KW - water productivity KW - wheat A1 - Abdelraouf, Ramadan E. A1 - El-Shawadfy, Mohamed A. A1 - Dewedar, Osama M. A1 - Hozayn, Mahmoud PB - Polish Academy of Sciences; Institute of Technology and Life Sciences - National Research Institute DA - 2021.06.09 T1 - Field and modelling study for deficit irrigation strategy on roots volume and water productivity of wheat SP - 129 UR - http://www.journals.pan.pl/dlibra/publication/edition/119859 T2 - Journal of Water and Land Development ER -