Accounting for phenology in maize yield prediction using remotely sensed dry dekads

Rain-fed agriculture is threatened by an increased frequency of droughts worldwide thereby putting millions of livelihoods at risk especially in sub-Saharan Africa. This makes drought preparedness critical. In this study, we sought to establish whether maize yield can be predicted using the number of dry dekads that occur at specific maize growth stages for purposes of yield early warning. The dry dekads were derived from remotely sensed Vegetation Condition Index calculated from the SPOT NDVI time series ranging from 1998 to 2013. Regression between dry dekads and maize yield show a negative linear relationship for four growing seasons (2010-2013) and indicates that dry dekads at both the vegetative and reproductive stages are important for predicting maize yield. Results suggest that early warning alert could be given using dry dekads that occur at the vegetative stage, while those at the reproductive stage can be used to give better yield estimate later on.