Effect of surface, subsurface and deep sewage drip irrigation systems on emitters perfomance and water use utilization for date palm

The objectives of this study are to investigate the effect of surface, subsurface and deep sewage drip irrigation systems on emitter performance and  water use utilization of Date Palm(Sukariah Cv)with different depths of irrigation water. These depths of applied water were 100% , 75% and 50% of  reference evapotranpiration ETo. The results showed that the values of mean emitter discharge (q¯), the relative emitter discharge (R) and  the reduction of discharge (qr)is greatly influenced by irrigation system in comparison with irrigation water depth. The values of emitters performance q¯ , R, qr  for surface drip (DI) and deep sewage drip irrigation (DSDI) treatments were greater than those for subsurface drip ( SDI) treatments. The values of emitter performance of DI and DSDI treatments had a higher values of distribution uniformity(DU)for all irrigation water depths  treatments  and for total irrigation time comparing with SDI. The value of Date Palm yield increased for  DSDI treatment  compared with those of DI or SDI treatments. The minimum value of Date Palm yield was 103 kg/tree  for the treatment (DI , 0.5 ETo ),while the maximum  values of  Date Palm yield were 175 and 172 kg/tree  for the treatments (DSDI , 1.0 ETo ) and  (DSDI , 0.75 ETo ), respectively. The maximum  values of  water use efficiency (WUE) were 1.34 and 1.31 kg/m3  for the treatments (DSDI , 0.5 ETo ) and  (DSDI , 0.75 ETo),