[Identification of fungal strain by Fourier transform infrared spectroscopy and cluster analysis]

Fourier transform attenuated total reflection infrared spectroscopy (FTIR-ATR) has been a novel technical procedure to identify and classify microorganisms in recent years. In the present study, Fourier transform infrared spectroscopy(FTIR) in combination with an attenuated total reflection (ATR) unit were used to discriminate important plant-destroying fungi. Mycelia of 17 fungal strains belonging to 14 different species were grown on potato dextrose agar (PDA) plants and subjected to FTIR-ATR measurements. High-resolution and well-reproducibility infrared spectra were obtained, and significant spectral differences among these strains were observed in the wavenumber regions of 1800-1485 cm(-1), 1485-1185 cm(-1), and 1185-900 cm(-1). According to the characteristic bands in these regions, cluster analysis was executed to classify the FTIR spectra. The result showed that different fungal strains could be identified correctly, demonstrating the high potential of FTIR-ATR as a tool for fungal strain identification and classification. The method is rapid, inexpensive and reproducible, and requires minimum sample preparation.