PLANT SYSTEMATICS AND EVOLUTION, vol.276, pp.191-198, 2008 (SCI-Expanded)
This study presents observations on the anatomical, palynological and ecological features of Tulipa gumusanica Terzioglu and its morphologically similar relative, T. armena Boiss. var. armena, in order to clarify their similarities and differences. We found that these taxa have some important differences with regard to anatomical, palynological and ecological features, as well as morphological traits. General anatomical traits of both examined taxa are similar, both having isolateral leaves with distinct hypodermis and a stem with distinct monolayer collenchyma close to the epidermis. However, some anatomical characters such as mesophyll width, average number of stomata on lower epidermis, and epidermal cells on upper epidermis are found to be important in delimiting these taxa. In addition, considerable differences have been observed in pollen shape and size. The species differ ecologically in that T. gumusanica prefers slightly acidic soil with low organic content in the woodland, whereas T. armena var. armena prefers slightly alkali soil with high organic content in steppe vegetation.