ENERGY REQUIREMENTS AND YIELD OF DRIP IRRIGATED POTATO

          Potato yield and quality are functions of the amonunt of irrigation water.
Irrigation system is one of the main parameters affecting irrigation efficiency, energy requirements and total irrigation cost.
Field experiments for two seasons (1999/2000) and (2000/2001), were carried out in Bosaily Experimental Farm, Beheira Governorate, in order to evaluate the performance of surface and subsurface drip irrigation systems.
Two different drip lines were used as surface and subsurface irrigation.
Three water requirement levels (75%, 100%, 125% from Et_o) were applied to find out the relationship between drip system and its effect on water use efficiency, energy consumption rate and cost.
         
Results indicated that there was no significant effect of the three rates of water requierments on total yield of potato.
Drip irrigation systems had highly significant effect on total yield of potato.
The highest yield of 14 ton/fed was obtained by using surface T-Tape drip irrigation at 125% of Et_c. On the other hand, minimum energy consumed value was 80.1 kW·h/fed under subsurface T-Tape drip irrigation . The minimum cost of production unit was 55.1 LE/ton using surface T-Tape drip at 75% of crop evapotranspiration (Et_c).