Hybrid Differences in Nutrient Uptake and Allocation: Implications for Fertilizer Management

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.