Irrigation management impacts on corn yield and nitrate leaching

University of Minnesota/Vasudha Sharma

The environmental impact of irrigated agriculture on ground and surface water resources in Minnesota is of major concern. Better irrigation scheduling has the potential in addressing these complex agricultural environmental challenges we face in Minnesota. The main goal of this research is to identify and develop irrigation management strategies and techniques that will increase corn water use efficiency, while minimizing nitrate leaching and maximizing crop utilization of soil nitrogen without impacting the yield. Four irrigation scheduling methods (1) in-field soil moisture monitoring using soil moisture sensors, (2) Irrigation Management assistant tool (IMA), (3) the University of Minnesota checkbook method, and (4) crop growth model (EPIC) will be evaluated and compared in terms of total volume of water used, nitrate leaching and corn yield for two corn growing seasons (2019-2020) at the Sand Plain Research Farm (SPRF) in Becker, MN. The other objective is to develop research based, easy-to-use irrigation management tools such as threshold trigger point for irrigation using Electric Resistance Sensors (watermark sensors) for coarse-textured soils. The outcomes of this research will provide tools, data and collaborations for the integration of best irrigation management strategies in agricultural best management recommendations and practices.