FT-Raman spectroscopy as a tool in evaluation the response of plants to drought stress

Abstract

The aim of study was to evaluate the usefulness of FT-Raman spectroscopy in assessing stress-induced metabolic changes in plants. 20-d-old optimally watered plants of soybean were exposed to drought. Metabolic changes in optimally watered and drought-stressed plants were monitored using FT-Raman spectroscopy. In parallel, analyses were carried out of fatty acid composition and pigment content using analytical methods. These compounds are associated with the response of plants to environmental stress. While fatty acid assays in study were inconclusive, the pigment content analysis gave promising results. FT-Raman experiment demonstrated a decrease in carotenoid content in leaf, as a result of drought, which was confirmed by spectrophotometric analysis. In addition to the analysis of aforementioned compounds, FT-Raman spectroscopy allowed the simultaneous observation of a wider spectrum of compounds scattering the radiation in the leaves tested, and their subsequent comparative analysis. The impact of drought on metabolism of soybean was clearly visible on spectra and confirmed using cluster analysis. The technical problem of the influence of leaf water content on measurements, which appeared in studies, will be discussed. To conclude, FT-Raman spectroscopy may be a good complement to other non-invasive methods, e.g., fluorescent methods, in assessing the stress-induced damage of crops.

Keywords

• carotenoids
• drought stress
• fatty acids
• ft-raman spectroscopy
• soybean