Red Edge Position (REP), an Indicator for Crop Stress Detection: Implication on Rice (Oryza sativa L)

Crop stresses due to both biotic and abiotic are the major factors affecting crop productivity. The need of the hour is to minimize the yield losses due to these stresses. Early detection can help to reduce the impact of stresses on crop growth and yield. Remote sensing techniques have been shown to be timely, non-destructive and provide spatial estimates for quantifying and monitoring crop stress as compared to direct field techniques. In this study we tested the possibility of detecting impact of abiotic stresses, mainly Nitrogen (N) and elevated CO2 and Temperature on growth and yield of rice crops based on the spectral reflectance data in the red edge position (REP). Spectral reflectances of crop canopyi from 350 to 2500 nm acquired using SVC spectroradiometer under clear sky condition between 11:00 and 13:00 IST. The results thus obtained indicate that REP is a good indicator of crop stress detection as healthy crops always are at longer wavelength as compared to crop under stress. The research work done also elucidates that REP can lead to the development of real-time management tool for crop stress detection, thereby reducing the yield losses due these stresses.