Comparison of foliar anatomy of Scorzonera L. (Asteraceae) taxa from North East Anatolia

Abstract

In the present study, the leaves of 18 Scorzonera L. (Asteraceae) taxa were studied by LM in order to assess anatomical variations that may serve as distinguishing characters and to evaluate their significance for the genus by numerical analysis. All the investigated species can be divided into distinct groups according to mesophyll and midrib structure. Firstly they can be divided in two groups based on presence/absence of cavity on midrib. Secondarily two main vascular bundle types can be identified in transverse sections according to the presence or absence of secretory cells in phloem. Principal component analysis (PCA) showed that width of the palisade tissue beneath the upper epidermis, rate of spongy to the mesophyll (w/w), average number of epidermal cells for both sides and average number of stomata on upper side are the most important characters in explaining the total variations.