Effect of Nitrogen on Seed Sugar Content in White Corn (Zea Mays L.)

Abstract A study conducted at Illinois State University research farms in 2021 and 2022 examined the A study conducted at Illinois State University research farms in Lexington, IL, during 2021 and 2022 investigated the effect of nitrogen (N) fertilizer on kernel sugar concentration, yield estimates, and grain mass in white corn (Zea mays L.). Using a randomized complete block design with two replications, nitrogen was applied as granular urea at rates of 0, 50, 100, and 150 kg N/ha. The grain yield was measured by hand-harvesting and shelling 1/1000th acre per plot and expressed as percent dry matter. Results showed no statistically significant differences between the replicates across the two seasons for sugar concentration, yield estimates, or grain yields. However, yield estimates increased linearly with higher nitrogen application rates, peaking at 150 kg N/ha. The average yield estimate was 12,552 kg/ha in 2021 and slightly higher at 12,687 kg/ha in 2022. Grain yield in 2022 exceeded that of 2021 by 844.1 kg. Nitrogen application also affected seed sugar content at all three milking stages. The findings suggest that nitrogen fertilization improves white corn yield and sugar concentration, but further research is needed to explore whether higher nitrogen levels maintain this linear trend. Additional studies should examine the moderating effects of weather conditions and soil moisture on nitrogen's impact on seed sugar content. Keywords: Sugar concentration, White Corn, Brix %, Refractometer, Nitrogen, Yield estimate, Grain yield, Kernels, Fudge factor.