A small plot experiment was carried out between 2011–2013 to determine the yield and water use of sweet maize in well irrigated (I2: ET 100%), water deficient (I1: ET 50%) and non-irrigated (I0) conditions. The dose of irrigation water was determined on the basis of evapotranspirational loss. The water use efficiency (WUE) of sweet maize was calculated as ear weight without husk of plots divided by seasonal ET. The irrigation water use efficiency (IWUE) was expressed as the ratio of yield in irrigated plots and total seasonal irrigation water applied, while the irrigation effect (IWUE2) was expressed as the yield difference between irrigated and rain fed treatments divided by amount of irrigation water.

There were small differences in average WUE values in the different treatments. Despite this fact, decreasing available water caused decreasing yield. Strong positive correlation was also found between the water use and yield of sweet maize.

The relationship between irrigation water use efficiency (IWUE) and the amount of harvested ear weight of sweet maize is strong. The correlation between the effect of irrigation (IWUE2) and yield is R2=0.668 in 50% water deficit and R2=0.884 in full irrigation.

During the experiment we concluded that the production of maize in different water supply conditions highly affects the water use of plants.

Keywords: sweet maize, water use, irrigation