Comparative morphology of the leaf epidermis in Fritillaria (Liliaceae) from China

The leaf epidermis of 16 species and one putative species of Fritillaria was examined using light microscopy (LM) and scanning electron microscopy (SEM). The results showed that the stomatal and other epidermal features were constant within species. Epidermal cells of Fritillaria under LM were usually polygonal and anticlinal cell walls were straight or curved. In a few species they were irregular, with sinuous anticlinal cell walls. The cuticular membrane of Fritillaria was usually striated, and the wax ornamentations were flaked, granular or concomitant. Based on leaf epidermal characteristics, the subdivision of Fritillaria is discussed, and the statistical t-test method was used to ascertain the significance level of the differences in the stomata of each species. All orientations of the stomatal poles in Fritillaria were the same, and this phenomenon was named 'stomatal orientation'. The stomatal characteristics support the origin of section Fritillaria in China from two floristic elements. (C) 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160, 93-109.