A study to elucidate the taxonomy of the genus Doronicum based on morphological and anatomical studies

Abstract

The main purpose of this study is the morphological and anatomical characterization of Doronicum L. taxa naturally grown in Türkiye. In this context, morphology and anatomy of 11 species, and 1 subspecies of Doronicum was researched in detail by stereo and light microscopy. Moreover, hierarchical cluster analysis (HCA) and principal component analysis (PCA) were performed to identify closely related species and the potential anatomical characters which could be used to delimitation the studied taxa. Although the anatomical features of the examined taxa are generally similar to each other, some differences have been identified. Since indumentum is significant in distinguishing taxa, trichome types and dimensions were also evaluated. The first four PCs explained about 66.28 % of total variability. Some anatomical characters such as cortical cell (stem), collenchyma thickness (stem), adaxial epidermis cell length (leaf), spongy parenchyma thickness (leaf), trachea cell diameter (leaf), adaxial stomatal index (leaf), trachea cell diameter (stem), and abaxial stomata length (leaf) resulted the most effective variables for the PCA. HCA dendrogram also revealed two main clusters. Determining the morphological and anatomical features of Doronicum taxa, clarifying the systematic value of anatomical features through numerical analysis and contributing to the systematic position of the examined taxa will be guiding for future studies.