A field experiment has been carried out in Autumn – 2013 on corn (Zea mays L.) var. 5018 to study the effect of irrigation depth on plant yield of total dry weight, cobs and grain. A surface drip irrigation system was used after field evaluation for the system at 50 Kpa pressure to determine the actual discharge of the emitters and some technical specifications of the system. The experiment included 13 treatments. namely; C100 as a control treatment, (V20, V40, V60 , V80) as a treatments that exposure to; 20, 40, 60 and 80% moisture stress in compare with control at vegetation stage, while (F20, F40, F60, F80), and (GF20, GF40, GF60, GF80) are treatments that exposure to the same ratios of moisture stress at flowering and grain formation stages, respectively. The treatments were distributed according to Randomized Complete Block Deign (R.C.B.D.). Total dry weight, cobs and grain were measured at the end of season.
Control treatment achieved the highest value of total dry weight, cobs and grain, which were 546, 298 and 230 gm.plant-1, respectively. In addition, the production of stress treatment (GF80) did not differ with control treatment. GF80 treatment achieved the highest rate of water use efficiency reached to 2.88 kg. m-3 comparison with 2.84 kg. m-3 for control treatment. Consumptive use was 732 mm.season-1 .which were 117, 325, and 157 and 124 mm at germination, vegetation, flowering and grain formation stages, respectively. The study proved that vegetative growth stage was the more sensitive for moisture stress than other stages.