Micromorphology and fatty acid composition of the cypselae of Xeranthemum cylindraceum Sm. (Asteraceae, Cardueae)

• Main Authors: Gavrilović Milan, de Oliveira Antonio Fernando M., Barbosa Mariana O., Garcia-Jacas Núria, Susanna Alfonso, Marin Petar D., Janaćković Pedja
• Format: Article
• Language: English
• Published: University of Belgrade 2018-10-01
• Series: Botanica Serbica
• Subjects: Xeranthemum; Cardueae; micromorphology; fatty acids
• Online Access: http://botanicaserbica.bio.bg.ac.rs/arhiva/pdf/2018_42_2_722_full.pdf
• ISSN: 1821-2158; 1821-2638

The paper presents micromorphology of the cypselae of Xeranthemum cylindraceum as revealed by scanning electron microscopy (SEM) and their fatty acid composition as determined on a gas chromatograph coupled with a flame ionisation detector (GC-FID). The cypselae are densely hairy, straight, ribbed, narrowly obconical to obovoid. Micromorphological features are as follows: striate-rugose surface; adaxial detachment area; asymmetrical carpopodium; presence of biseriate, nonglandular, shortly forked twin hairs; and absence of a pericarp crown. The pappus is paleaceous, homomorphic, uniseriate, persistent, and with several wide, scarious, subulate, and apically pinnulate bristles of variable length. Out of 12 fatty acids detected, nine (88.57%) are identified, ranging from palmitoleic (C16:1) to behenic (C22:0) acids. Oleic acid is dominant (55.24%). Unsaturated fatty acids are predominant in the oil (75.02%). The composition of fatty acids in cypselae of the given species is here reported for the first time. The taxonomic value of the analysed characters is briefly discussed