Leaf anatomical notes on Cirsium Miller (Asteraceae, Carduoideae) from Turkey

Abstract Here, we describe the leaf anatomical characters of 26 Cirsium taxa (33 accessions) native to the northeast region of Turkey, with the aim of evaluating their taxonomic significance within the taxa. Leaf anatomies of all taxa were characterized and compared using cluster analysis and multidimensional scaling analysis. The transverse sections of the leaves showed various numbers of vascular bundles and accessory bundles. In addition, significant differentiations were observed in the midrib and lamina thickness, the height and width of vascular bundle, and number of stomata, and epidermal cell wall patterns in the abaxial and adaxial surfaces among the taxa. These results demonstrate that the compared anatomical characters among taxa are partly in accordance with their sectional delimitation in the Flora of Turkey. However, our data suggest that some taxonomic re-arrangements might be necessary. Based on its anatomy, we propose that the Cirsium taxa can be treated as pioneers. Some ecological interpretations are also made.