Water and Nitrogen Application Levels for the Optimum Tomato Yield and Water Use Efficiency

This study was conducted to determine the effects of different water and nitrogen application levels on drip-irrigated tomato plants. The amount of water usage was based upon the pan evaporation from a screened (class “A”) evaporation pan. The treatments consisted of two irrigation intervals (I۱= ۵ days and I۲= ۱۰ days), three plant-pan coefficients (Kcp۱= ۰.۵۰; Kcp۲= ۰.۷۵ and Kcp۳= ۱.۰۰) and three nitrogen (N) levels (N۰ = ۰, N۱= ۸۰ and N۲= ۱۶۰ kg ha-۱). The I, Kcp and N levels affected the tomato yields and water usage efficiencies, however the effects of nitrogen applications were found to be greater than those of the other applications. Consequently, to reach the maximum tomato yields under similar climate and soil conditions, plant-pan coefficients (Kcp) and nitrogen values should be equivalent to ۱.۰۰ and ۱۶۰ kg ha-۱, respectively.

Keywords:

Irrigation , N fertilization , Pan evaporation , Plant-pan coefficient , Tomato