Hyperspectral Spectroscopic Transmittance data collected in-vivo tomato leaflets in controlled conditions

Hyperspectral point-of-measurements (HS-POM) were collected in vivo from the adaxial side of healthy and diseased leaflets of nine tomato plants, in a dark room (in detail, three Control plants, three plants inoculated with Pseudomonas syringae pv. tomato, and three plants inoculated with Xanthomonas euvesicatoria). For each plant, spectral assessments were performed randomly on nine points of different leaflets, belonging to the 4^th, 5^th, and 6^th expanded leaves.

Hyperspectral data were acquired using a Hamamatsu Photonics K.K. TM Series C11697MB spectrometer, which covers a wavelength range of 200-1100 nm with a spectral resolution of 0.6 nm. A transmission optical fiber bundle (FCR-7UVIR200-2-45-BX, Avantes, Eerbeek, The Netherlands) with a range of 200-2500 nm was used along with a stainless-steel slitted reflection probe that was positioned 0.5 cm above the sample surface to capture the leaflet's spectral signal and direct it to the spectrometer's entrance lens. A white LED light was placed underneath the leaflet to provide uniform illumination to its entire abaxial surface. The spectral range of the LED emits light from 390 to 800 nm. Therefore, the LED spectra were used as a reference to the spectral range measured by the spectrophotometer and to check measurement and light emission stability. The hyperspectral transmittance data were collected using specialized evaluation software (SpecEvaluationUSB2.exe, Hamamatsu Photonics K.K., Japan).

For more detailed description of the bacterial inoculation assays and the remain experimental conditions, please check:

Reis Pereira M, Santos FNd, Tavares F and Cunha M (2023) Enhancing host-pathogen phenotyping dynamics: early detection of tomato bacterial diseases using hyperspectral point measurement and predictive modeling. Front. Plant Sci. 14:1242201. doi: 10.3389/fpls.2023.1242201