Nitrogen and Water Rate Interactions On Corn Growth and Production in Nebraska.

Continuing advances in variable rate technology for irrigation (IR) and nitrogen (N) have created new opportunities to maximize efficiency for major crop inputs.  A study was designed to measure the response of corn (Zea mays L.) to a combination of different IR and N rates in Nebraska.  Two study locations were used in 2011 and 2012 on contrasting soil types and precipitation regions.  Treatments were designed as split plots consisting of five N rates (0 to 280 kg ha^-1) within three rates of irrigation (100% to rain fed).  Irrigation treatments were applied by sprinkler at both sites, while N was split applied with half the total rate applied pre-plant with the balance applied at V-10.  In 2011, normal to above precipitation occurred at both locations.  At one location, significant grain yield responses to N and IR were seen, as well as interaction between N and IR.  The second location did not respond to IR or N.