Assess spectral reflectance signatures by difference calculation.

a,b,c Spectral differences of healthy and inoculated with B. graminis f.sp. hordei (Bgh), susceptible WT, resistant mlo3 and Mla1, 0.5, 12, 24, 48 and 72 hai. Positive values in the difference plot demonstrate higher reflectance intensity of healthy leaves, negative values higher reflectance intensity of inoculated leaves. In addition, schemes of the interaction types development are illustrated. On pseudo RGB image from HSI, no symptoms are visible. Based on the reflectance spectrum, computed disease maps indicate Bgh infested pixels in white 72 hai. HR maps indicated pixels, which undergoes a hypersensitive response also in white 72 hai. (n = 8 biological replicates).