Comparative anatomical investigations on six endemic Tanacetum(Asteraceae) taxa from turkey

Abstract

Tanacetumis one of the large genera, belonging to the Anthemideaetribe of Asteraceaefamily and has numerous medicinal plants and widely usage in folk medicine. In this study, anatomical features of six endemic species to Turkey viz. Tanacetum albipannosum, T. argenteumsubsp. argenteum, T. cappadocicum, T. densumsubsp. sivasicum, T. haussknechtii andT. heterotomum, were investigated for the first time. The specimens were collected from their natural habitats in Sivas province (Turkey). Transverse sections of root, stem, petiole andleaflet were observed under light microscope for various anatomical features. The results showed that, root included periderm in the outer. There were parenchymatous cortex, endodermis and pericycle under the periderm respectively. Primary xylem ridges were triarch in T. albipannosum, T. densumsubsp. sivasicum, T. haussknechtii andT. heterotomum, pentarch in T. cappadocicumand hexarch in T. argenteumsubsp. argenteum, and pith was filled with xylem elements. Stem was made up epidermis, parenchymatous cortex, endodermis, vascular bundles and parenchymatous pith from exterior to interior. T. heterotomum had a cavity formed by the disintegration of the cells in the center. The amphistomatic leaflets had a single layered epidermis with usually silvery or whitish tomentose indumentum and equifacialmesophyll. Stomata are anomocytic. There were significant difference among examined taxa in respect to contour of petiole, structure of cortex parenchyma and organization of vascular bundles. The anatomical characteristic features of petiole proved to be a useful tool for the taxonomic discrimination of the six studied taxa. © 2016, Pakistan Botanical Society. All rights reserved.