Relevance of Fourier transform infrared spectroscopy and leaf anatomy for species classification in Camellia (Theaceae)

Fourier transform infrared spectroscopy (FTIR), a rapid, simple, high-resolution analytical method, provides biochemical profiles containing overlapping signals from numerous compounds present in cells. FTIR analysis of leaves of twenty-one species in four sections of Camellia (one is sect. Longissima, two in sect. Longipedicellata, sixteen in sect. Thea, and two in sect. Glaberrima) was conducted to determine whether they can be discriminated on the basis of biochemical profiles. The results showed that the spectra were highly typical for different species. A hierarchical dendrogram based on prinicipal component analysis of FTIR data confirmed the morphological classification of the four sections proposed in previous work. Quantitative and qualitative leaf anatomy characteristics, such as pattern and size of epidermal cells, cuticular ornamentation, layer of epidermal cell, and thickness of palisade parenchyma and spongy parenchyma, provided additional taxonomic evidence.