Anatomical properties of four Pilosella Vaill. (Asteraceae) taxa from Eastern Black Sea Region of Turkey

Anatomical features of four Pilosella Vaill. taxa (P. officinarum Vaill., P. piloselloides (Vill.) Sojak subsp. bauhini (Schult.) S. Bräut. & Greuter, P.× hypeurya (Peter) Sojak, P. densiflora (Tausch) Sojak) collected from Black Sea Region of Turkey were investigated. Anatomical studies include transverse sections of root, stem and leaf with their illustrations. Although the anatomical properties are similar to the typical anatomy of dicotyledons, some differences were observed among them. While root anatomy of P. officinarum, P. piloselloides subsp. bauhini and P. densiflora consist of a single layer exodermis, there is 2-3 layer exodermis in the natural hybrid P. × hypeurya. Additionaly the root pith of this hybrid taxa completely composed of schlerenchyma cells in contrast to other investigated taxa. The stem anatomy of the investigated taxa is similar to each other except the number of the tracheidal elements. The numbers of the stomata per µm2 disticltly differ in P. piloselloides subsp. bauhini from the rest examined taxa