Date of Graduation


Document Type


Degree Name

Master of Science in Crop, Soil & Environmental Sciences (MS)

Degree Level



Crop, Soil & Environmental Sciences


Larry C. Purcell

Committee Member

Trenton L. Roberts

Second Committee Member

Douglas Karcher

Third Committee Member

Jason Kelley


Corn, Dark Green Color Index, Leaf nitrogen, Nitrogen, Pretassel, Remote Sensing


There are a lack of tools to assess midseason nitrogen (N) status in corn (Zea mays L.) production systems and identify the need for additional N fertilization. This study was conducted to determine the ability of leaf N concentration (LN) and the Dark Green Color Index (DGCI) at the 10th collared leaf stage (V10), the 12th collared leaf stage (V12), and tasseling (VT) to predict if midseason N is required to maximize corn grain yield. From 2017 to 2019, eight field studies with 11 N treatments ranging from 0 to 258 kg N ha-1 were conducted on silt loam soils in Arkansas. Leaf samples and digital images were collected at V10, V12, and VT growth stages. Relative grain yield (RGY) was predicted as a function of LN between V10 and VT which was described by a linear-plateau regression (R2 = 0.82, P-value < 0.0001). Model predictions indicated that RGY increased linearly up to a LN concentration of 30.4 g N kg-1 and there was no additional increase when LN was greater than 30.4 g kg-1. Measurements of DGCI from the high N treatment (258 kg N ha-1) were included in the regression analysis as a reference DGCI (RDGCI) to account for differences in environmental lighting when aerial images were captured. A multiple regression equation described the relationship between LN, DGCI, and RDGCI (Pvalue