Varco, Jac J.

Committee Member

Henry, W. Henry

Committee Member

Fox, Amelia Ann Amy

Committee Member

Cox, Michael S.

Date of Degree


Document Type

Graduate Thesis - Open Access


Plant and Soil Sciences - Agronomy

Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Plant and Soil Sciences


Single-rate blanket application of fertilizer nitrogen (N) can result in an over or under application. Variable rate (VR) applications tailored to actual crop demands can improve N use efficiency in spatially variable soils. The objective of this study was to compare and improve relationships derived between corn canopy reflectance and corn N status acquired with two sensing platforms. Four fertilizer N rates were used, from deficient to excess, to create varying corn N status. Sensing and biophysical sampling was taken throughout the season for analysis and comparison to calculated vegetation indices (VIs). Results show strong relationships between VIs and corn N concentration and the strongest found using combined indices that incorporate the red-edge wavelength (720 nm). Relationships strengthened at latter growth stages. Results and models from this study demonstrate the utility of using remote sensing technologies to more accurately predict corn N status for eventual use in VR prescription development.



Corn||Variable Rate||Nitrogen||Remote Sensing||Vegetation Index