Nitrogen Use Efficiency In Winter Wheat Varieties.

With fertilizer prices continuing to increase, winter wheat producers are looking at ways to cut input costs and increase their profitability margins.  A major input cost in production comes from the price and application of nitrogen fertilizer.  Winter wheat producers could lower costs associated with nitrogen fertilizer by selecting varieties with increased nitrogen use efficiency.  The objective of this study was to determine the nitrogen use efficiency of 30 different winter wheat varieties grown during the 2010-2011 growing season.  For the experiment, we set up a split block design in which we looked at nitrogen rates of zero and 89.7 kilograms per hectare applied on 30 winter wheat varieties.  Nitrogen use efficiency (NUE) was calculated by looking at grain yield per unit of nitrogen applied and nitrogen available in the soil.  Nitrogen use efficiency was further broken down into nitrogen uptake efficiency (NUPE), which looked at total nitrogen at maturity per unit of nitrogen supply, and nitrogen utilization efficiency (NUTE), which looked at grain yield per total nitrogen at maturity. Soil samples were collected and analyzed for available N before planting and tissue samples were collected at heading and maturity.  We also measured grain yield at harvest and analyzed the grain for nitrogen.  We expect differences among the 30 winter wheat varieties in their nitrogen use efficiency.  This data can be very useful for plant breeders in helping them select for wheat varieties that will not only be high yielding but also efficiently take up and utilize nitrogen.  Producers will also benefit from this data in that they will be able to select wheat varieties with higher nitrogen use efficiency and thus help them save money on input costs.