Maize (Zea mays L., 1753.) evapotranspiration ando crop coefficient in semi-arid region of Ethipia

Maize (Zea mays L.,1753) plays an important role in the economy of maize-growing nations. Supplying the right amount of water to a crop based on its needs is the main agenda for implementing water-saving agriculture. Non-weighting lysimeters were used to determine the actual crop evapotranspiration and crop coefficient of maize at the experimental farmland of the Melkassa Agricultural Research Center, Ethiopia. Soil-water balance approaches were applied to obtain actual crop evapotranspiration, while the Penman-Monteith technique was used to compute reference evapotranspiration. The growth stages-wise crop coefficient was calculated as the ratio of the actual crop evapotranspiration ratio to the reference evapotranspiration. The total seasonal maize actual crop evapotranspiration during the 2017 and 2018 experimental years was 503.7 and 511.06 mm, respectively. The 2-year average maize actual crop evapotranspiration was 507.4 mm. The mean locally developed actual crop coefficient values of 0.55, 1.19, and 0.56 were observed for the initial, mid, and end seasons, respectively. The FAO-adjusted crop coefficient for the mid-season was 1.15. The developed Kc values differed considerably from the FAO-adjusted Kc values. Therefore, the determination of actual crop evapotranspiration and crop coefficients for crop growth under local climatic conditions is vital for decision-making concerning agricultural water management in areas where irrigation is practiced.