Irrigated and rain-fed maize response to different nitrogen fertilizer application methods

With the demand for maize increasing, production has spread into more water limited regions. Couple this with increasing resource costs and environmental concerns and the need for efficient nutrient and water management practices has increased. The objective of this trial was to evaluate the effects of different nitrogen (N) fertilizer application methods and timings on maize grain yield, N use efficiency (NUE), and water use efficiency (WUE) under irrigated and rain-fed conditions. Four site-years of data were collected. Fertilizer treatments consisted of all N applied preplant, split surface applied, and split foliarly applied. Irrigation applied prior to and during reproductive growth increased grain yield, NUE, and WUE compared to rain-fed treatments for all site-years. Split surface applied N fertilizer applications typically increased NUE, but not always grain yield compared to preplant applications. The use of split foliar N fertilizer applications was only beneficial in the site-years when leaf burn was not as severe.