Spectral Remote Sensing of Tomato Plants (Lycopersicon esculentum L.) Infected with Tomato Mosaic Virus (ToMV)

摘要

Leaf spectral reflectance and virological analyses were performed to establish the efficiency of the non-invasive remote sensing technique as a tool for diagnostics of plant diseases. The potential of certain chemicals such as benzo-(1,2,3)-thiadiazole-7-carbothioic acid-S-methyl ester (BTH), beta-monomethyl ester of itaconic acid (MEIA), polyamine Spermine and Phytoxin VS to induce systemic acquired resistance (SAR) in tomato plants (Lycopersicon esculentum L.) against a Tomato mosaic virus (ToMV) was investigated. The plants, cultivar Ideal sensitive to ToMV, were grown in a greenhouse under controlled conditions. They were divided into six groups - control (healthy), inoculated with ToMV, treated with four chemicals and then inoculated with ToMV. The leaf spectral reflectance was measured with a portable spectrometer (Ocean Opties) in the visible and near infrared ranges. The viral concentrations in the plant leaves were determined by the serological method Double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). On the 7th and 14th day after carrying out the inoculation, specific differences of the reflectance spectra were found to appear in certain wavelength intervals between virus-infected and control leaves. The changes lied in the green (near 520-580 nm), red (640-680 nm), red edge (690-710 nm) and near infrared (720-760 nm) range. The statistical significance of the differences in these intervals was established using the Student t-criterion. The changes in the leaf reflectance spectra and their correlation with the DAS-ELISA results for ToMV presence suggest the spectral reflectance technique as a promising tool for cost-effective, non-destructive and sensitive method for diagnosis of virus disease.