Imaging system of solar-induced plant fluorescence for monitoring of plant living status

We developed a practical field-based method of sensing the physiological status of live plants. The potential of detecting solar-induced plant fluorescence, which originates in chlorophyll molecules, through a non-destructive and remote sensing method was investigated. We constructed a plant fluorescence imaging system that adopted the Fraunhofer line discrimination (FLD) method in which the A-line (atmospheric oxygen absorption band of 760.78 nm) was used. The performance of the system was tested using three types of sampled leaves. Fluorescence intensities from their images produced with the system were highly correlated with fluorescence obtained from fluorospectrometer measurements (R²=0.95). We were able to produce fluorescence imaging of a redrobin living in field, including leaves, stems and branches. Fluorescence intensity varied with the chlorophyll content of each component.