Integration of Sensor Based Fertigation Management.

The over application of nitrogen (N) fertilizer to maize and application asynchrony in relation to plant demand exacerbated by soil type and depth to groundwater has led to the contamination of groundwater by nitrate in Nebraska. Research and Extension along with partnerships with local regulatory agencies, have noted a steady rise in nitrogen use efficiency in specific areas of Nebraska. However, the increases have plateaued. New best management practices are needed to be developed that extend gains further to remediate nitrate contamination in the aquifer. One potential best management practice is sensor based fertigation. Research was conducted at two sites that represent different environments and soils (SCAL and WCREC) across two years: 2016 and 2017. The study compared the available spectrum of best management practices for N in Nebraska as recommended by University of Nebraska. In 2016, the WCREC site was heavily damaged from hail, and data was discarded. At SCAL in 2016, yield was not significantly different between treatments with the control being the exception. Nitrogen rates had a range of 98 to 254 kg/ha. The sensor-based fertigation treatment used the least amount of N with no statistical difference in yield. Initial results are encouraging, but more site-years coupled with larger scale on-farm research need to be evaluated before including this method as a new best management practice to recommend to maize growers in Nebraska and beyond.