Advancements in corn hybrids have generated higher yields; however, fertilization practices have not necessarily evolved with these innovations. Researchers at the University of Illinois conducted a study in 2010 to evaluate nutrient uptake and removal in modern corn hybrids, as well as the timing of nutrient uptake.
The trial assessed six hybrids with genetic resistance to the Western Corn Rootworm and European Corn Borer, along with other species in the Lepidoptera order.1 Nutrient contents were collected at V6, V10, V14, R2, R4 and R6. While the study examined 10 corn nutrients, below is a summary of the average nutrient analyses for nitrogen (N), phosphorus (P), potassium (K), sulfur (S) and zinc (Zn).
The research team found the majority of N is taken-up during the vegetative phase with 65 percent of N-uptake complete by R1. The majority of N uptake occurred from V10 through V14.
A little more than half of P uptake, 56 percent, occurred after VT/R1. Also, nearly 80 percent of P was removed with the grain, more than any other nutrient.
Similarly to N, the research determined 63 percent of K uptake happened before the R1 phase. However, only one-third of total K accumulation was removed with the grain.
Uptake of S was nearly equal between vegetative and reproductive growth stages. In addition, 57 percent of S was contained in the grain and removed from the field.
During the later growth stages, Zn uptake was the greatest with more than half of uptake occurring after VT/R1. Additionally, nearly two-thirds of zinc accrual was removed with the grain.
Results from the study showed major elements are accumulated in the plant at different rates throughout the growing season, highlighting the need for proper nutrient availability during peak growth stages. Moreover, the research team found with higher yielding hybrids, certain elements are removed in higher quantities with the grain causing a depletion of soil nutrient levels.