Applicability of Ground-based Remote Sensors for Crop N Management in Sub Saharan Africa

Abstract

Remote sensors have a growing legacy for improving crop N use efficiency (NUE) in several parts of the world. The technology employs crop spectral properties to determine fertilizer rates by matching crop N requirement based on midseason yield potential. Conclusions that the technology is inappropriate for Sub Saharan Africa (SSA) because the farmers use little or no fertilizer, or cannot afford it, are reviewed. Opportunities and applicability using a model concept from the GreenSeeker sensor ($4000) are presented. Because farmers in SSA inefficiently apply fertilizer through blanket recommendations, they must improve crop NUE to minimize cost. Application of this technology would enable refinement or development of N recommendation protocols for target groups of farmers based on site and delineated management field zones. With new developments of a prototype GreenSeeker, the Optical Pocket Sensor (