Dergi makalesi Açık Erişim

Achene micromorphology of 26 Crepis L. (Asteraceae) taxa from Turkey with notes on its systematic and ecological significance

2018    Kalmuk, Nursen Aksu; Inceer, Huseyin; Imamoglu, Kemal Vehbi

In this study, achene surface sculpturing and pappus ultrastructure of 26 Crepis taxa from Turkey were investigated using scanning electron microscopy (SEM). The achene microcharacters in the studied taxa were described here for the first time. Considerable differences in the shape of the epidermal cells and the ornamentation type of the outer cell wall have been found at interspecific levels. The differences in the achene surface sculpturing are also associated with achene dimorphism and habitat in some taxa. There are remarkable differences in the shape of the epidermal cells on the ribs of the achene among some clades within Crepis. The pappus ultrastructure is similar in all the taxa and is composed of spiky cells. Statistically significant difference has been found in the diameter of the pappus bristles among the taxa. It is concluded that achene micromorphology is useful for delimitation of the Crepis taxa. The microsculpture patterns on the ribs of the achene can also be used as a marker among major phylogenetic lineages as well as between closely related species. Additionally, the achene surface sculpturing could play an important role in the colonization of new habitats as well as in the adaptation to higher altitudes.