EFFECT OF MOISTURE STRESS ON YIELD AND WATER USE EFFICIENCY OF MAIZE (Zea mays L.) AT MELKASA, ETHIOPIA

Abstract

At present and so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the normal rather than the expectation, and irrigation management will shift from emphasizing per unit area towards maximizing the production per unit of water consumed, the water productivity. The purpose of this study was to determine the water use efficiency of maize under moisture stress condition and to identify the critical depth of application with limited effect on yield. Field experiment was conducted at Awash Melkassa (Melkassa agricultural research center farm). The experiment was carried out in randomized complete block design with eight treatments and three replications. The treatment consists of seven moisture stress levels and one control (full irrigation, 85% ETc, 75% ETc, 65% ETc, 55% ETc, 45% ETc, 35% ETc and 25% ETc). Daily crop water requirement (ETc) was estimated by multiplying reference evapotranspiration with crop coefficient. The result reveals that the moisture stress levels set had significant impact on grain yield and crop water use efficiency. The highest grain yield was obtained from full irrigation (5524.8 Kg/ha) which was not significantly (P<0.01) different to the 85% ETc (5406.5 Kg/ha) whereas, the lowest grain yield is obtained from 25% ETc (1468.6 Kg/ha). In terms of field and water use efficiency 25% ETc gives the highest field water use efficiency and crop water use efficiency followed by 35% ETc and 85% ETc. Therefore, it can be concluded that increased water saving and associated water productivity through the use of 85% ETc, can solve the problem of water shortage which improves water use efficiency without significant reduction of yield. But if the water scarcity is high in the area 75% ETc appears to be a promising alternative for water shortage with negligible trade-off in grain yield and water use efficienc