Abstract
This research was conducted at one farm of the Agriculture and Forestry College. Zea maize class 106 was planted in the lysimeters with a dimensions of 2*2*1 meters. Three irrigation treatments have been chosen with two deblicates. The first one was full irrigation (FI) which irrigated to 100% of available water after consumed 50% of it. The 2nd treatment was deficit irrigation (DI) which they were irrigated to 50% of available water after depletion and 75% .The 3rd treatment were partial root zone drying (PRD) which was irrigated to 50% of available water after depletion 75%. The consumptive use was measured by a lysimeter method and was estimated by the following equations: Class Pan A ,FAO-PM-Grass and FAO-PM-Alfalfa and these values were 310.82 , 264.42 , 242.26 , 195.85 mm.sea-1 respectively. Water use efficiency showed high values when the consumption use was measured by FAO-PM-Alfalfa through all irrigation treatments, while these values decreased when the consumptive use was measured by the other methods. The values of yield response parameter were decreased to 0.48 , 0.68 when the consumptive use was measured by the following methods lysimeters , Class Pan A , FAO-PM-Alfalfa respectively for the second deficit irrigation treatment, however the values of these parameter were increased in the third PRD treatment where the consumptive use methods.PRD treatments showed high consternation values of Abscisic acid during the vegetative and flowering stages 29.64 , 33.14 mg.L-1 for the third treatment, however the concentration values of this acid was lower in both full and deficit irrigation treatments.
