Spectral differences of opposite sides of stripe rust infested winter wheat leaves using ASD´s Leaf Clip

Stripe Rust, caused by Puccinia striiformis f. sp. tritici, has emerged as one of the most destructive foliar diseases of winter wheat (Triticum aestivum L.) and caused great yield loss. The primary objective of this study is to identify the stress characteristics of wheat leaves caused by such a disease. After performing artificial inoculation of stripe rust, hundreds of leaves with different infections were collected and leaf reflectance were conducted using ASD´s (Analytical Spectral Devices) leaf clip probe. Based on the nonequivalent optical properties on the opposite side of a leaf, their spectral characteristics were specifically compared and the correlations between disease severity indices and water or chlorophyll were further analyzed. The final results indicated that, for the face and back sides of stripe rust infected wheat leaves, some obvious differences existed in the spectral reflectance and correlation curves between foliar disease severity indexes (FDSIs) and reflectance, especially with the increase of infections.