Corn hybrids change rapidly and most Corn Belt hybrids have a 2-3 year commercial lifespan. Seed company claims often suggest, based on their internal research or grower field experiences, that certain hybrids respond more to higher rates of fertilizers than others. There are also known hybrid differences in grain nutrient concentrations, and therefore in actual crop removal at particular yield levels. In this talk I will review preliminary evidence for possible hybrid differences in total nutrients taken up and in how the nutrients are allocated within corn plants at maturity. I will also briefly look at plant population impacts on nutrient uptake and nutrient partitioning during the growing season. Hybrid differences, if they are substantial, could have implications for optimum management assumptions for fertilizer applications. Public sector research on these hybrid by fertilizer management questions is very limited, but our recent preliminary investigations may provide some helpful clues to 4R nutrient recommendations for corn.
Dr. Tony J. Vyn is a Professor and Cropping Systems Extension Agronomist in the Department of Agronomy at Purdue University. Tony grew up on a hog and cash crop farm near Chatham in Southwestern Ontario, Canada. He earned his degrees from the University of Guelph, (in Guelph, Ontario) and was a faculty member in the Crop Science Department at the same university from 1987 until he left for Purdue University in 1998. Dr. Vyn advises several graduate students in research focused on understanding the interactions of tillage, crop rotation, plant density, and (or) nutrient placement systems with crop response and soil properties. His current investigations include corn hybrid and plant density comparisons at multiple N rates, tillage comparisons (like no-till and vertical tillage versus strip tillage), RTK automatic guidance for strip tillage and nutrient banding, plant-to-plant variability in corn, nitrogen rate and nitrification inhibitor impacts on greenhouse gas emissions, and crop response to micronutrient applications. He has served as Extension Coordinator for the Agronomy Department at Purdue and as Associate Editor for Agronomy Journal, Crop Science and Soil and Tillage Research. Tony has enjoyed being Co-Chair of the Indiana Crop Advisor Conference since 2003. In his spare time, he particularly enjoyed cash-crop farming with his own family from 1980 to 1998.