With the improvement of mobile computing, the company Spectrum Technologies, Inc. has developed a precision Ag App which adapts an iPod, iPad, or iPhone camera to select for specific wavelengths of light from a corn leaf (Zea mays L.) in comparison to accompanying board for light/color comparison. The App computes a Dark Green Color Index (DGCI), indicating leaf greenness, which relates to the amount of chlorophyll and thus, indirectly, leaf nitrogen (N) content. The question posed for this study is: How accurate and convenient is the App compared to a proven technology, the Minolta 502 Soil-Plant Analysis Development (SPAD) meter; do they provide the same information?
Iowa State University
Pille, Jessica D.; Sawyer, John E.; and Barker, Daniel W., "Comparing the FieldScout GreenIndex+ Chlorophyll Sensing App to the Minolta SPAD Meter" (2011). Agronomy Conference Proceedings and Presentations. 9.