Fourier-Transformed Infrared Spectroscopy Applied for Studying Compatible Interaction in the Pathosystem Phytophtora infestans-Solanum tuberosum

In this study we used the Fourier-Transformed Infrared (FT-IR) technique to examine the compatible reaction of potato (Solanum tuberosum) to infection by the late blight agent Phytophthora infestans. Three virulent isolates have been used, different by their level of pathogenicity on R2 potato. The response was dependent on the pathogenicity of the isolate. The Infrared spectra in the middle infrared region (MIR) of infested versus healthy (control) leaves showed that controls absorb (intensity) mostly in the range 650-950 cm-1.The absorbance was higher for the most virulent isolate in the range 950-1650 cm-1. In the domain 3000-4000 cm-1 for the control and less pathogenic interactions, have absorbed more than the highly infested samples. The shape of spectra has generally been the same shape. However, the number of peaks suppressed/induced after inoculation and in function of the isolate differs indicating a perturbation of plant metabolsim. FTIR technique provides important information about the events occurring during the interaction.