Evaluation of Two Crop Canopy Sensors for Nitrogen Recommendations in Irrigated Maize

Crop canopy sensors can provide valuable information about in-field nitrogen (N) variability in maize (Zea mays L.) and can serve as the basis for in-season N recommendations. However, few studies have been conducted to determine how the sensors compare. Therefore, a study was conducted using the two most prominent crop canopy sensors (NTech's GreenSeeker™ red and Holland Scientific's Crop Circle™ amber) to determine if the different sensors recommended different amounts of N at the V12 maize growth stage. Results show that each sensor recommended the same amount of N at the V12 growth stage (N recommendations by sensor were not significantly different). The N algorithms developed for each sensor also calculated unbiased N recommendations suggesting that the methodology of algorithm development was valid as was the estimate of required N at maize growth stage V12. Therefore, both crop canopy sensors performed equally in terms of N recommendations in this study.