Impacts of Drought Stress and Planting Methods on Sweet Corn Yield and Water Use Efficiency

Seasonal drought is the most important factor to limit the production of maize in the world. Using a split plot design, a two year field experiment was conducted to determine the effect of limited irrigation regime on yield, yield components and water use efficiency of sweet corn (Zea mays var. saccharata). Responses of three sweet corn varieties KSC403, Merit and Obsession to three different water regimes were studied under two planting methods (raised bed and furrow planting). The three water levels (I1: 100%, I2: 80%, I3: 60%) of the estimated crop evapotranspiration (ETc)) were arranged as main plots. Combination of the two planting methods and three sweet corn varieties were arranged in subplots. The evaluated traits were significantly affected by varieties (p<0.01). The highest ear length and diameter and biomass belonged to Merit. Fresh ear weight was significantly affected by the interaction of variety and irrigation level. The highest (19.7 ton/ha) and lowest (7.4 ton/ha) yields (fresh ear weight) belonged to Merit at 100% and KSC403 and obsession at 60% irrigation level, respectively. There was no difference between planting methods with respect to the measured traits. Results showed that limited irrigation significantly decreased kernel number per row by increasing the anthesis-silking interval, which decreased grain yield. Biomass decreased by decrement of water amount. The reduction in fresh ear yield and biomass decreased water use efficiency (WUE), but there was no significant difference between I1 and I2 irrigation levels for WUE.