Evaluation of Late Maturing Corn Hybrids for Yield and Water use Efficiency under Different Irrigation Regimes and Split-Application of Nitrogen Fertilizer

The present study aimed to evaluate the growth and water use efficiencies of eight late-maturing corn hybrids in comparison to the common use of KSC704 and Maxima-FAO530 under different water-nitrogen management systems. Two irrigation regimes (based on 50% soil-water depletion as the normal irrigation and, on average. 16% less than normal as the deficit irrigation) and two nitrogen (N) application managements (3 and 16 split-application of 150 kg N from Urea, 45% N) were induced using the split-split plot experiment based on a completely randomized block design with four replications at Research Field of Isfahan University of Technology on 2017. The results showed that yield, forage and leaf area index were significantly (P<0.01) affected by the interaction of three studied factors (Irrigation × Nitrogen × Corn hybrid). For different corn hybrids, more water use efficiencies were achieved by deficit-irrigation regime and 16- split-applyication of N; in this regard, the SC719 hybrid had the highest value of 3.45 kg m-3. Generally, the performances of the studied late maturing corn hybrids were higher than those of the control hybrids of SC704 and SC530 at this planting date, which could be improved by using the deficit-irrigation regime and more split-application of the N fertilizer.