Precision Nitrogen Fertigation Using NDVI Crop Sensors Integrated with a Lateral Move Irrigation System

The goal of this research was to vary the Nitrogen fertigation rates in lateral move irrigation systems (LMIS) based on the measurements from NDVI sensors in real time. For this purpose, handheld GreenSeeker sensors were modified to parse out the NDVI data directly from the sensors’ printed circuit boards (PCB) to Arduino microcontrollers. GreenSeekers, Arduinos, GPS receivers and XBEE S2C radios were integrated to create sensor nodes that are capable of sending NDVI data and receiving specified zone application rates to control solenoid valves to apply nitrogen within sensor nodes’ designated zones. Ten sensor nodes were mounted along the boom of an LMIS. Each sensor node’s longitude, latitude, date, and time are recorded for every NDVI measurement on a micro SD card. The NDVI values are used to calculate and vary the required rate of nitrogen for application while the lateral moves across the field. In this paper, the accuracy of NDVI data from the GreenSeeker sensors and the system’s competency at calculating and varying nitrogen rates will be presented.