Determination of evaporation and transpiration in irrigation water management using the O-18 Stable Isotope technique

One of the primary barriers to economic progress in arid and semi-arid areas is water scarcity. As a result of the water shortage in Egypt, a field experiment was conducted to wheat plants evaluate the effect of drought on wheat at different levels of irrigation which are 100%, 80% and 60% of the water requirements of wheat. A neutron probe was used to estimate the absolute moisture content of the soil. Stable isotopes of oxygen and deuterium were used to Quantify evaporation and transpiration. The results showed that growth parameters decreased by water levels of irrigation according to the following arrangement 100% > 8% > 60% The values were respectively 6986, 6470, 5306.67 and the water use efficiency respectively 1.36, 1.56, 1. 671. Generally, the results indicated that drought was characterized by early maturity, a short grain filling period, a short plant height and the lowest grain yield/plant.