Mid-infrared spectroscopy is a fast screening method for selecting Arabidopsis genotypes with altered leaf cuticular wax

Arabidopsis eceriferum (cer) mutants with unique alterations in their rosette leaf cuticular wax accumulation and composition established by gas chromatography have been investigated using attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy in combination with univariate and multivariate analysis. Objectives of this study were to evaluate the utility of ATR-FTIR for detection of chemical diversity in leaf cuticles, obtain spectral profiles of cer mutants in comparison with the wild type, and identify changes in leaf cuticles caused by drought stress. FTIR spectra revealed both genotype- and treatment-dependent differences in the chemical make-up of Arabidopsis leaf cuticles. Drought stress caused specific changes in the integrated area of the CH3 peak, asymmetrical and symmetrical CH2 peaks, ester carbonyl peak and the peak area ratio of ester C(sic)O to CH2 asymmetrical vibration. CH3 peak positively correlated with the total wax accumulation. Thus, ATR-FTIR spectroscopy is a valuable tool that can advance our understanding of the role of cuticle chemistry in plant response to drought and allow selection of superior drought-tolerant varieties from large genetic resources.